YALE JOURNAL OF BIOLOGY AND MEDICINE 76 (2003), pp. 63-77.Copynght © 2003. All rights reserved.

MEDICAL REVIEW

The Specialty of Colon and Rectal Surgery:Its Impact on Patient Care and Role in AcademicMedicinea

Walter E. Longo

Department of Surgery, Division of Gastrointestinal Surgery,Yale University School of Medicine

The specialty ofcolon and rectal surgery, a specialty of general surgery, has evolvedfrom the fieldof proctology. Clinical care has demonstrated decreased number of patients requiring intestinalstomas, improved quality of life in patients with benign anorectal disorders, and more favorableresults in patients afflicted with primary and recurrent colorectal cancer. Basic science investiga-tions have spawnedfrom clinical questions such as the molecular biology of colorectal cancer, useofcyclooxygenase inhibitors and polyp regression, and novel cytokine antagonists in inflammatorybowel disease. Medical students are exposed to surgeons with expertise in anorectal anatomy andphysiology, mechanisms ofcarcinogenesis and the importance ofscreeningfor detection ofcolorec-tal cancer, and novel therapiesfor inflammatory bowel disease. Surgical residents benefit by havinga colorectal surgeon on the faculty by repetitive exposure to anorectal surgery, low pelvic anasto-moses, stoma creation and closure, and surgery involving the small intestine. Senior colorectal sur-geons will develop critical pathwaysfor the healthcare delivery ofpatients afflicted with colorectaldisease. The specialty ofcolorectal surgery will continue to translate into improved patient care andpositively impact in academic medicine by providing expertise into student and resident training andgenerate highly sophisticated clinical and basic science investigations.

INTRODUCTION

The controversy over specialization inmedicine has existed for almost 100 years.Specialization has evolved to provide carefor specific populations, for explicit servicesand as a result of new technology. Clearly,the healthcare market demands driven bythe consumer have championed demands

to no end. Specialization provides state-of-the-art knowledge and care of complexareas, high volumes of routine procedures,educational benefits to students and those inpostgraduate training and intangibly pro-vides the answers to questions that continueto appear in the clinical arena that need tobe translated from bench research to evi-denced based medicine. This is all so true

To whom all correspondence should be addressed: Walter E. Longo, M.D., Department ofSurgery, Division of Gastrointestinal Surgery, 333 Cedar Street, FMB 102, Yale UniversitySchool of Medicine, New Haven, Connecticut 06510. Tel.: 203-785-2697.a Presented as part of the Leon E. Sample Memorial Lecture, Department of SurgeryYale University School of Medicine, November 20, 2002.b Abbreviations: CT, computed tomography; FDG-PET, flurodeoxyglucose positron emissiontomography; FAB, familial adenomatous polyposis; HNPCC, hereditary non-polyposis colorectalcancer; MRI, magnetic resonance imaging.

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64 Longo: The Specialty of Colon and Rectal Surgery

for the specialty of colon and rectal surgery.The surgical anatomy is challenging; phys-iology is better understood but unknown tothose outside the specialty; pharmacologyis playing a crucial role as in the mediatorsof the anal sphincters; and pathology is never-ending. Clinically, the issues are challenging:fears of stomas in cancer surgery, youngadults undergoing major intestinal resec-tions for inflammatory bowel disease, life-altering bowel dysfunction in patients withfecal incontinence and constipation, andanal disease that if mismanaged can bequite costly to the patient and surgeon. Theopportunities for investigation are numer-ous and include colorectal cancer genetics,biological therapies for colorectal cancer,mediators of inflammation, implantabledevices, tissue engineered intestine androbotics. This review will discuss the spe-cialty of colon and rectal surgery as it relatesto its evolution, training and board certifi-cation, spectrum of clinical activity, educa-tional initiatives, and frontiers of research.

EVOLUTION OF THE SPECIALTY

It was Frederick Salmon founder ofSt. Mark's Hospital, whose interests in analfistulas and other diseases of the rectumattracted his successors, William and HerbertAllingham, to create the new specialty ofproctology in the mid-1800s. In 1878, itwas the American Dr. Joseph Matthewswho upon noticing that in his practice inKentucky a lack of interest and attentionfor patients with rectal problems, went tostudy with Dr William Allingham. Upon hisreturn to Kentucky, he announced that hewas going to limit his practice to diseasesof the colon and rectum and becameAmerica's first full-time proctologist. Helater became Professor of Surgery in theKentucky School of Medicine and in 1883,established the Department of Proctologyin the Medical School [1]. Since the 1880sthere have always been a few surgeonswho devoted special attention to colon andrectal surgery. Until lately, the vast bulk of

bowel surgery remained in the hands ofgeneral surgeons. In the United Kingdom,surgeons such as Percy Lockhart-Mummeryand John Golligher, paved the way for spe-cialization in colon and rectal surgery. Inthe United States, recognition of colon andrectal surgery as a distinct field has onlybecome evident over the past twenty years [2].

AMERICAN BOARD OF COLONAND RECTAL SURGERY

Since its inception in 1899, theAmerican Proctologic Society has beeninnovative and, above all, concerned withpatients needs. Always moving forward,members of this society organized andincorporated into the American Board ofProctology in 1935. It was the sixth specialtyboard to be organized and tenth board to beincorporated. After becoming a subsidiaryof the American Board of Surgery from1935 to 1949, there were continued effortsfor independence. After continuing effortsto gain independent status, in February1949, The American Board of Proctologywas granted independent status. Over the nextten years, the Board became active notonly in examining and certifying physi-cians but also involved in medical educa-tion. On April 15, 1961, the AdvisoryBoard for Medical Specialties grated theAmerican Board of Proctology to adoptthe name The American Board of Colonand Rectal Surgery. In 1980, the Boardmandated completion of a general surgeryresidency and becoming board certified ingeneral surgery prior to being able toacquire board certification in Colon andRectal Surgery [3, 4].

FELLOWSHIP TRAINING ANDBOARD CERTIFICATION

During the chief-resident year, aprospective board eligible general surgeryresident makes application through theNational Residency Matching Program forfellowship training in colon and rectal

Longo: The Specialty of Colon and Rectal Surgery 65

surgery. There are currently 41 trainingprograms in colon and rectal surgerythroughout the United States and Canada.The number of fellows in each programranges from one to four. The fellowship isof one-year duration of clinical colon andrectal surgery with certain programs havingthe option for an additional year of researchor further clinical training as a fellow.Upon completion of training, candidates forboard certification in colon and rectalsurgery must be in good standing, submit acase log to the board, and demonstrateboard certification in general surgery. Tobecome board certified, a written examina-tion including sections in pathology andradiology must be passed (qualifyingexamination) and an oral certifying exam-ination will certify the applicant as boardcertified in colon and rectal surgery.Physicians with an interest and expertiseare encouraged to become a member of theAmerican Society of Colon and RectalSurgeons. Recertification for those certifiedafter 1990 is every ten years.

IMPACT ON PATIENT CARE

Benign anorectal disease

Hemorrhoids: Hemorrhoids are one ofthe most common gastrointestinal disor-ders affecting nearly 5 percent of theUnited States population. It is estimatedthat two and a half million persons per yearvisit physicians for treatment [5]. Therapycan be broadly categorized into oral therapysuch as fiber, topical treatments, nonsurgicaldestructive techniques, and surgical inter-vention. The decision to treat is based onthe nature, frequency, and severity ofsymptoms. It is also based upon patientpreference and operator experience. Theoverwhelming majority of patients whoseek treatment will receive conservativetherapy where the goal is to relieve symp-toms and maintain remission. Fiber sup-plements and increased water intake areoften first-line therapy, however the results

remain inconsistent. Regardless, fiber sup-plements given over six weeks are superiorversus placebo for reduction of bleedingsymptoms [6]. It will remain first-line therapybecause it is safe and inexpensive. Topicaltherapies reduce symptoms by exerting alocal anesthestic effect eliminating thesymptoms of burning and itching. A num-ber of topical therapies are available. Onlyone randomized trial utilizing 5-ASA sup-positories demonstrated significant reductionin hemorrhoidal symptoms when comparedto placebo [7]. Bleeding or other symp-toms that persist despite conservative man-agement require more aggressive therapy.This entails either non-surgical options orsurgical hemorrhoidectomy. The goal ofnon-surgical therapy is tissue fixation ofthe hemorrhoid pedicle. These methodsinclude rubber band ligation, injectionsclerotherapy, and infrared coagulation.None of these techniques have been inves-tigated individually against placebo-con-trolled trials [8]. However, randomized tri-als comparing these modalities with eachother have been performed. These resultsfailed to demonstrate a clear advantage andappear to be equally effective. Two meta-analyses [9, 10] comparing all threemodalities have been performed. Both trialsdemonstrated IRC and RBL to be moreefficacious than sclerotherapy. IRC requiredrepeat treatment, while RBL was signifi-cantly more painful. The decision to pro-ceed to surgical hemorrhoidectomy requiresa mutual decision between the patient andphysician and is reserved for patients whofail non-operative therapy [9]. It is alsoindicated for the rare instances of acutelythrombosed and gangrenous internal hem-orrhoids. When contemplating surgery, therisk of complications, postoperative pain,and cost must be realized. A number ofexcisional techniques have been describedand are performed in the operating roomunder local, regional, or general anesthesia.Despite its effectiveness, few patientsshould require excisional hemorrhoidectomy.Laser hemorrhoidectomy results in delayed

66 Longo: The Specialty of Colon and Rectal Surgery

bleeding, increased pain and increasedcost. The most significant change in hem-orrhoid surgery is the use of the circularstapler. A randomized controlled trialexamining pain, complications, cost, andrecurrence using this modality is underway.

Anal fissure: Fissure-in-ano is a com-mon condition seen by primary care physi-cians and surgeons. It presents with painafter defecation that persists for a variableperiod of time and may be associated withrectal bleeding. Although the pathogenesisoften remains poorly understood, it is feltto be related to a combination of spasm ofthe internal anal sphincter and relativeischemia of the posterior midline of theanal canal. Other etiologies of an anal fis-sure, especially when located away from themidline, should be sought out. Manometricstudies have demonstrated high restinganal canal pressures and ultraslow pressurewave activity in the internal anal sphincter.Classic treatment involves stool softeners,fiber supplements, and warm, tub baths.This will heal about 30 percent of fissures.If the fissure does not heal, then it becomeschronic. This is manifest by anatomic signssuch as exposed anal sphincter fibers, sen-tinel piles, and hypertrophic anal papilla.The standard classic treatment followingfailure of conservative therapy involves asurgical anal internal sphincterotomy,which is effective in the overwhelmingmajority of patients. Various refinementsin the procedure, open versus closed, par-tial versus total have occurred [10, 11].Currently, full thickness, partial, lateralsphincterotomy is what is supported.Regardless, division of the internal analsphincter may result in variable degrees offecal incontinence especially in womenwho have undergone vaginal delivery withoccult sphincter damage. This rare, but dis-tressing complication, has resulted in sur-geons seeking alternatives to conventionalsphincterotomy. The neurotransmitter inthe internal anal sphincter leading to relax-ation is nitric oxide. Chemical sphinctero-tomy utilizing nitric oxide donors applied

to the anal margin of patients with anal fis-sure have been utilized with variable suc-cess [12-14]. Alternative agents have alsobeen investigated. Botulism toxin injectionprevents the release of acetylcholine bypresynaptic nerve terminals and injectioninto the internal anal sphincter lasts clini-cally for three to four months. The internalanal sphincter has a calcium dependentmechanism and an extrinsic cholinergicinnervation which can be exploited toreduce resting anal pressure. Topical dilti-azem and bethanechol are currently beinginvestigated and may be additive [16].Surgery is referred for medical treatmentfailures or to meet immediate patient wishes.Operative techniques commonly used foranal fissure include anal stretch, open andclosed lateral sphincterotomy, posteriormidline sphincterotomy, and dermal flapcoverage. Anal stretch has a higher risk ofpersistence of fissure symptoms whencompared to sphincterotomy and carries ahigher risk of incontinence. There is littledifference between open and closed lateralinternal sphincterotomy regarding persis-tence of fissure and risk of incontinence. It isunclear whether posterior midline sphinc-terotomy should be primary surgical treat-ment [11]. The management of anal fis-sures will continue to evolve similar to thatof hemorrhoids in that there will be less analsphincterotomies performed in the future.

Fistula-in-ano and abscess: A fistulais defined as an abnormal communicationbetween any two epithelial lined surfaces.A fistula-in-ano is an abnormal tract orcavity communication with the rectum oranal canal by an identifiable internal open-ing. These result, in the majority of cases,from a previous anorectal abscess andbecome a fistula secondary to chronicity.The classification by Parks is the mosthelpful classification currently. There arefour classifications of fistula-in-ano: inter-sphincteric, transsphincteric, suprasphinc-teric, and extrasphincteric. These are oftencryptoglandular in nature but may alsoarise as a consequence of Crohn's disease

Longo: The Specialty of Colon and Rectal Surgery 67

and other infectious etiologies. For chal-lenging cases, especially in the presence ofrecurrence, physical examination should besupplemented with fistulography, intrarectalultrasound or magnetic resonance imaging(MRI)b [17]. It is extremely rare for a fis-tula-in-ano to heal by conservative mea-sures. The principles of fistula surgery areto eliminate the fistula, prevent recurrence,and preserve sphincter function. The typeof fistula will often dictate which operativeprocedure should be performed. Fistulotomyusing the lay-open technique is used forthe treatment of simple intersphinctericand low trans-sphincteric fistulas. Theproblem of preserving anal continence andtreating the fistula is more complicatedwhen treating high intersphincteric fistu-las. Insertion of a seton in combinationwith a lay open technique may be safer inthis situation [18]. In patients with hightrans-sphincteric fistulas and suprasphinc-teric fistulas, consideration to a anorectaladvancement flap should be given [19].Extrasphincteric fistulas, which are exceed-ingly rare, depend on the etiology (abscess,Crohn's disease, or foreign body) andoften require fecal diversion along witheliminating the fistula. Impaired conti-nence is greatly feared following fistulasurgery. This, along with varying recur-rence rates have caused surgeons to seeksphincter muscle sparing techniques totreat anal fistulas. The use of tissue adhe-sives or sealants in surgery has increasedbecause of improved autologous and com-mercially available products. A number ofstudies have now demonstrated fistula clo-sure rates at approximately 85 percent [20,21]. Functional results have remainedexcellent. Future investigations are neces-sary to determine the most effective fibringlue type and operative technique to improveon these results.

Ulcerative colitisMany of the surgical innovations in

surgery have impacted favorably on thetreatment of ulcerative colitis. This includes

the Brooke ileostomy, the ability to suc-cessfully and safely complete an ileorectalanastomosis, the Kock continent ileosto-my, and finally the ileal pouch anal anasto-mosis. The etiology of ulcerative colitisremains obscure, however environmental,dietary and genetic factors continue to beimplicated [22]. It is a disease with abimodal peak in age that affects men andwomen equally. Innovative medical thera-pies such as the development and ability todeliver adequate amounts of 5-ASA com-pounds to the colon, development of novelsteroid compounds with minimal sideeffects and immunosuppressive therapieshave all contributed to the well being ofpatients [23]. The primary indication forsurgery remains intractability with acutesurgical emergencies less so and surgeryfor invasive cancer exceedingly rare.Aggressive colonoscopic surveillance hasresulted in detection of dysplasia and masslesions, which has hopefully translatedinto fewer operations for cancer. Procto-colectomy with construction of an ileoanalreservoir anastomosis is the procedure ofchoice and may be either a staged or singleprocedure. There remains complicationsrelated to the procedure such as anasto-motic dehiscence, which may result inchronic pelvic sepsis or anal stricture aswell as pouch fistula to either the vagina orperineum. Remedial operations to correctpouch derangements such as advancementflaps or creating a neo-reservoir can besuccessfully performed in experiencedhands [24]. In properly selected patients,the ileoanal pouch anastomosis providespatient satisfaction at over 90 percent [25].Patients are plagued with pouchitis resultingin watery diarrhea that often responds tometronidazole. Probiotics are currentlyunder investigation to balance pouch ecology.In patients felt not be candidates for arestorative operation, proctocolectomy andBrooke ileostomy improves quality of lifeand rids the patient of medication. Inpatients who have had a previous procto-colectomy and sacrifice of the anal sphinc-

68 Longo: The Specialty of Colon and Rectal Surgery

ter mechanism, a continent ileostomy may beconsidered. Patients with "indeterminatecolitis" have been shown to be candidatesfor a restorative proctocolectomy [26].

Crohn's disease

Crohn's disease is associated withtransmural involvement of any portion ofthe gastrointestinal tract and, similar toulcerative colitis, no specific etiology hasbeen identified. Medical therapy hasreduced the number of reoperations and isalso utilized to prevent recurrence after allgross disease has been removed at surgery.Because of the nature of this disease,patients are plagued with obstructivesymptoms secondary to strictures, sepsisas a result of perforations and fistulas, andthe challenges of managing their perianaldisease. Clearly, tremendous advances havebeen made regarding the potential etiolo-gies, pathophysiology, diagnostic imaging,medical therapies, and role of nutritionalsupplementation of this disease since itsinitial descriptions in the early 1900s. Effortsto elaborate on each of these issues isbeyond the scope of this article, and readersare encouraged to review the myriad ofpapers addressing each of these issues.

Surgery remains an integral part oftreatment and should not be viewed asdoom and gloom. Clearly the results ofoperative therapy have dramaticallyimproved patients quality of life, even inthe setting of temporary or permanent fecaldiversion [27]. Surgery for small and largeintestinal disease has evolved from bypassprocedures and extensive intestinal resec-tion to a more conservative approachinvolving conservative surgical therapies.This has been facilitated by the use ofinterventional radiology involving percu-taneous drainage of abscesses, total par-enteral nutrition including its use in thehome setting, and the use of medical ther-apy in the postoperative setting followingresection of all macroscopic disease. Wideintestinal anastomoses using linear sta-pling techniques, the use of limited (< 2

cm) resection margins, and the techniqueof strictureplasty has decreased short andlong term morbidity and improved qualityof life [27, 28]. Similarly, conservativeresectional treatment involving the colonalso continues to evolve [29].

Two areas deserve special interest,they being acute surgical emergencies andperianal Crohn's disease. The morbidityand mortality for acute emergencies suchas toxic colitis, hemorrhage and perfora-tion has somewhat diminished due toimprovements in surgical technique andintensive care medicine. It is also my per-ception that patient compliance to medicalcare and specialization in gastroenterologyin the area of inflammatory bowel diseasehas potentially reduced the number of sur-gical emergencies.

Perianal Crohn's disease has continuedto plague surgeons because of the fear offecal incontinence, uncontrolled pelvic sep-sis, and the need for removing the patientsrectum necessitating permanent colostomy.Currently, conservative approaches involvingdrainage of abscesses with mushroomcatheters, use of non-cutting setons, antibi-otics, and anti-TNF therapy has resulted incontrolled sepsis and preservation of function.

Colorectal cancer screeningCurrent colorectal cancer screening

options include fecal occult blood testing,flexible sigmoidoscopy, air-contrast bariumenema, fiberoptic colonoscopy, virtualcolonoscopy, and stool DNA tests.Guidelines for screening revolve aroundwhether you are a high-risk or average-riskpatient as well as the results of the initialscreening procedure. Fecal occult bloodtesting is non-invasive, least expensive,and most widely available but has subopti-mal sensitivity and prevents the fewestcancers. Barium enema is inexpensive andcost-effective but insensitive when com-pared to colonoscopy. Fiberoptic colonoscopyis very sensitive for colorectal lesions, butis most invasive and costly. Stool DNAtesting is evolving. This is promising tech-

Longo: The Specialty of Colon and Rectal Surgery 69

nology because colorectal cancers containgenetic mutations or inactivated genes.The test hopes to identify genetic abnor-malities in colonocytes shed in the stool.Early clinical studies suggest that multi-target, DNA-based stool tests are capableof detecting both premalignant adenomasand cancers with high sensitivity andspecificity. This form of testing is attrac-tive because it is non-invaive, requires nobowel preparation or dietary restrictionsand requires a single specimen [30].

Screening colonoscopy is cost-effec-tive and provides high patient satisfactionbecause it provides effective diagnosis andtreatment in a single session. Virtualcolonoscopy (Computed tomography [CT]and MR) colonography performance relieson the use of state-of-the-art scanners,computer workstations and trained radiol-ogists. Both CT and MR colonographycurrently report excellent sensitivity equalto colonoscopy and the advantage ofMR islack of ionizing radiation [31].

Inherited colon cancer

Approximately 80 percent of patientswith colorectal cancer appear to have spo-radic disease whereas approximately 20percent have a potentially definable inher-itable component. Several hereditary syn-dromes caused by specific germline muta-tions have been characterized and accountfor 5 to 6 percent of all colorectal cancerpatients [32]. These include familial ade-nomatous polyposis (FAP), hereditarynon-polyposis colorectal cancer (HNPCC),Peutz-Jeghers syndrome, and juvenilepolyposis. When used appropriately, genetictesting is available for diagnosis of themajor inherited syndromes of colon can-cer. FAP is an autosomal dominantly inher-ited syndrome that arises from germlinemutations of the APC (adenomatous poly-posis coli) gene. Clinically it is character-ized by the occurrence of hundreds to thou-sands of colorectal adenomatous polyps atan early age and inevitably colon cancerunless colectomy is performed. In addition

to polyps, patients with FAP can develop avariety of extracolonic lesions. Theseinclude both benign and malignant tumors.The diagnosis is confirmed by the pres-ence of 100 or more adenomas on colono-scopic examination. Also the diagnosis ofFAP can be confirmed by genetic testingfor the APC gene mutation. It will be pre-sent in 80 to 90 percent of affected indi-viduals. If the mutation is found in pedi-gree, yearly sigmoidoscopy should begin atage 12, decreasing in frequency after eachdecade up to age 50, at which time screen-ing should conform to American CancerSociety guidelines for average risk patients[33]. Surgery is recommended at the timeof diagnosis to minimize the risk of malig-nancy. There are several options includingtotal abdominal colectomy with ileorectalanastomosis or total proctocolectomy witheither ileostomy or ileoanal pouch anasto-mosis. If the rectum can be cleared endo-scopically, rectal preservation is preferred.Surveillance of the rectum is performed.Cyclooxygenase inhibitors have beenshown to be effective in inducing regres-sion of polyps in the retained rectum.

HNPCC is an autosomal dominantinherited disorder that accounts for 3 to 5percent of all colorectal cases. It is causedby a mutation in any one of the five mis-match repair genes. Colorectal cancer arisesfrom a single flat polypoid lesion in theabsence of polyposis. It is characterized bya young age for developing colorectal can-cer, multiple tumors, proximal lesions, andmetachronous tumors within 10 years ofresection. Similar to FAP, other cancerscan occur in HNPCC especially gyneco-logical. The phenomenon on microsatelliteinstability is found in 90 percent ofHNPCC tumors and is the first step ingenetic testing followed by MMR genetesting to confirm the diagnosis. In apatient with HNPCC who develops col-orectal cancer, subtotal colectomy with ile-orectal anastomosis is recommended.Postoperative endoscopic surveillanceshould be performed every six months

70 Longo: The Specialty of Colon and Rectal Surgery

[34]. It is uncertain whether prophylactichysterectomy and oophorectomy is indicated.

Rectal and anal cancer

The management of rectal cancer hasprogressed tremendously over the past 100years, in part because of an increasedunderstanding of the pathology and naturalhistory of the disease [35]. Currently,surgery remains the mainstay of therapyand includes a spectrum of operative pro-cedures both radical and local with a trendtowards increased number of sphinctersparing procedures. Preoperative diagnosticimaging has provided preoperative assess-ment of locoregional and distant diseaseand aids in decisions of whether to employpreoperative neoadjuvant therapy involvingradiation and chemotherapy [35]. Regard-less, outcome appears to be related totumor biology, stage of the lesion at pre-sentation, and type of operation per-formed. Recently, the impact of the sur-geon performing the operation may alsoinfluence outcome [36]. Preoperative imagingremains an essential part of the assessmentof the patient with rectal cancer. CT is usefulin assessing patients thought to harbor exten-sive local or metastatic disease. Endorectalultrasound is the best method for evaluatingloco-regional disease. It is highly accuratefor detecting depth of invasion and less sofor perirectal lymph nodes. Magnetic reso-nance imaging (MRI) can also detect localtumor extension. Nuclear medicine tech-niques utilizing either flurodeoxyglucosepositron emission tomography (FDG-PET)and immunoscintigraphy are utilized todetect occult or recurrent cancer [35].Radiation therapy is an integral part oftreatment for patients with rectal cancer.Its role is to decrease local recurrence andhopefully translate into improved survivalrates. In the preoperative setting, radiationcan increase respectability of bulky lesionsand increase chance of sphincter preserva-tion in distal lesions. Intraoperative radiationtherapy is applied to locally advanced pri-mary and recurrent rectal cancer. Postoper-

ative adjuvant chemotherapy has shownsurvival benefit with the optimal regimenevolving.

Anal cancer is rare and accounts for 1to 6 percent of all anorectal neoplasms. Itis important to distinguish anal canal fromanal margin neoplasms as the former aremore aggressive. The goals of treatmentare cure, local control, sphincter salvage,and avoiding permanent colostomy. Thereremains various histiotypes, with squa-mous cell being most common while ade-nocarcinoma arising from the anal glandsand anal melanoma being uncommon.Throughout the 1970s, abdominoperinealresection was the standard treatmentresulting in a permanent colostomy, highlocal recurrence rates, and low five-yearsurvival rates. Nigro initiated the force ofchange and began the first successful useof combined fluorouracil and mitomycinwith external beam radiation as potentiallycurable therapy [37]. Today modificationsof Nigro's protocol remain the standard ofcare for treatment of squamous cell carci-noma of the anal canal. Abdominoperinealresection remains salvage therapy fortreatment failures with variable survivalrates. Anal adenocarcinoma is treated sim-ilarly to that of rectal adenocarcinomaemploying surgery with or without adju-vant chemoradiation. Anal canal melanomahas a continued poor prognosis wheresurgery is the only meaningful method oftreatment with the goal being local control[38].

Fecal incontinenceFecal incontinence remains one of the

most devastating conditions. Its exact inci-dence remains unknown but varies between1 to 3 percent and up to 7 percent in healthyadults over 65 years of age [39]. There is ahigher rate in women secondary to obstetric-related structural sphincter damage. Theetiologies are numerous and are often relatedto obstetrical trauma, previous anal surgery,rectal prolapse, pelvic floor denervation,radiation, and following sphincter-saving

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operations. Fecal incontinence may beeither passive or urgent in nature. Passiveincontinence relates to losses occurringwithout patient awareness usually associ-ated with internal sphincter dysfunctionand reduced maximum resting anal pressure.Patients with urgency incontinence areunable to defer defecation, which usuallyreflects either external sphincter dysfunc-tion or excessively strong bowel contrac-tion that cannot be opposed by the externalsphincter pressure. A careful history andphysical examination is imperative to dif-ferentiate isolated sphincter dysfunctionfrom general metabolic and neurologicdisorders. Special physiologic examina-tions have allowed the physician to permitassessment of the anal sphincters, puden-dal nerves, and pelvic floor. These includeanal manometry, cinedefecography, elec-tromyography, anal ultrasonography, andmagnetic resonance imaging [40].

Many patients can be managed bymeans of pharmaceutical products such asantidiarrheals or behavioral modificationsuch as biofeedback. Daily colonic irriga-tion remains another alternative but haspotential adverse sequelae. A number ofsurgical procedures are available for thetreatment of anal incontinence. Most oper-ations attempt to restore the sphinctermechanism and anorectal angle. Theseinclude either anorectal muscle repairssuch as direct apposition and overlappingsphincteroplasty or total pelvic floor repair[41]. Severe multifocal damage to thesphincter complex may not be suitable fordirect sphincter repair and require either astatic or dynamic neosphincter repair [42].These include gluteus and gracilis muscletranspositions or free muscle transposi-tions involving sartorius muscle. Implanta-tion of an artificial sphincter was initiallypopularized in 1992 and remains underinvestigation [43]. Finally, the creation ofan intestinal stoma remains the last optionfor treatment of incontinence. This can beperformed laparoscopically. Neurogenicincontinence remains a difficult condition

and may benefit by biofeedback and otherconservative measures [44].

Functional and pelvic floor disorders

The majority of functional pelvic floordisorders are the result of or result inabnormal defecatory habits. Often thesedisorders have constipation as the predom-inant symptom [45]. Sophisticated physio-logical testing and diagnostic imagingtechniques have identified the etiology ofmany of these defecatory disorders andresulted in therapies to patients who wouldhave previously been ignored. Paradoxicalor non-relaxing puborectalis syndrome(anismus) occurs when the puborectalisinappropriately contracts or fails to relaxduring defecation resulting in pelvic outletobstruction. The diagnosis is confirmedwith a combination of anorectal manometry,electromyography and cinedefecography.Biofeedback therapy is the initial treat-ment of choice [46]. Treatment failuresmay respond to Botox injections. Surgeryhas no role. The Descending PerineumSyndrome has a similar presentation asanismus with obstructed defecation as thepredominant symptom. It is felt to be sec-ondary to many years of straining to defe-cate. It is diagnosed by perineometric mea-surements and cinedefecography. Treatmentis limited to nonoperative methods includ-ing biofeedback. A rectocele may also pro-duce obstructed defecation. The diagnosisis made by a history of straining and theneed for digital rectal or vaginal evacua-tion. Physical examination provides thediagnosis in about two-thirds of caseswhere the rectum is seen bulging into thevagina. Defecography will reveal the rec-tocele and provide useful informationabout the anorectal angle. Treatment is ini-tially conservative. Surgery is recommend-ed for patients rectocele's greater than 4cm partial emptying during defecographyand the need to digitally evacuate. A widerange of transvaginal, transrectal, andtransperineal procedures have been advo-cated with variable success. Rectal prolapse

72 Longo: The Specialty of Colon and Rectal Surgery

is full thickness protrusion of the rectumthrough the anal sphincters. Internal or"hidden" prolapse occurs when the rectumintusscepts, but does not pass beyond theanal canal. Symptoms include protrusion,bleeding, fecal incontinence, and a senseof incomplete rectal emptying. Full thick-ness rectal prolapse must be differentiatedfrom rectal mucosal prolapse seen in asso-ciation with advanced hemorrhoidal dis-ease. Management of rectal prolapse issurgical [47]. Over 100 procedures havebeen described. They may either beabdominal or perineal. Normal anatomy isrestored. A widely variable effect of pro-lapse surgery on disturbed evacuationoccurs. Continence is often restored.

Intestinal stomas and alternatives toconventional ileostomy

During the first half of the twentiethcentury, an ileostomy was associated withsignificant morbidity secondary to serosi-tis of the exposed bowel wall. This wasrectified by the development of the tech-nique of an everting ileostomy in 1952 byBrooke [48]. This dramatically changedsurgical treatment and life with an ileostomy.Nevertheless, patient dissatisfaction of aconstantly draining stoma and the require-ment of a full-time pouch caused physi-cians to develop alternatives. In 1969, NilsKock [49] described the creation of an ilealreservoir drained by an access segmentthrough the rectus muscle. He modified thiswith a nipple valve of intusscepted ileumcreating complete continence. A furthermodification was proposed by WilliamBarnett who developed the Barnett reser-voir utilizing a living collar of ileum wrappedaround the neck of the pouch to improvecontinence [50]. The utility of these proce-dures has diminished as a direct conse-quence of the creation of the ileoanalpouch for the treatment of ulcerative colitisand familial adenomatous polyposis.Although pouch salvage following analand perineal complications of restorativeproctocolectomy continue to improve, there

is a role for a continent ileal stoma in the eventhe pouch can not be salvaged [51, 52].

Anorectal physiological testing

Manometric, electrophysiologic andradiologic techniques used in combinationprovide important basic information nec-essary to understand anorectal and pelvicfloor disorders. Anorectal physiologicaltesting evaluates the function of theanorectum, pelvic floor, and anal sphincters[53]. Its utility centers mostly on the eval-uation of fecal incontinence [54]. The testsused most frequently are anorectal manom-etry, pudendal nerve terminal motor laten-cy, concentric needle EMG, single fiberEMG, cine defecography, and colonictransit studies. Anorectal manometry uti-lizes various catheters probes and record-ing devices to determine resting sphincterpressures, anal sphincter length, maximumsqueeze pressures, rectoanal inhibitoryreflex, and rectal sensory volumes. Indica-tions for anorectal manometry includeevaluating patients with chronic constipa-tion determining whether the patient hasHirschprung's disease as evidenced byabsence of the anorectal inhibitory reflex,to quantitate a sphincter defect and assesscontribution of the neural and muscularcomponents necessary for fecal conti-nence. Electromyography is the recordingof electrical activity generated by musclefibers and can be measured either duringvoluntary contraction or at rest. It is usedto evaluate muscles whose nerve supplymay have been damaged and thus is valu-able in patients with pelvic floor disordersand fecal incontinence. It can be recordedwith surface electrodes, concentric needleelectrodes, and single fiber electrodes.Pudendal nerve terminal motor latency isbest evaluated for anal sphincter injurysecondary to trauma or vaginal deliveryprior to surgical repair and evaluation ofidiopathic fecal incontinence. Concentricneedle EMG allows for selective recordingof muscles of interest such as the puborec-talis in patients with anismus [55].

Longo: The Specialty of Colon and Rectal Surgery 73

Imaging of the anal sphincters andpelvic floor

Recent advances in ultrasonographyhave improved significantly the accuracyand applicability of intrarectal and intra-anal ultrasonography to the managementof benign and malignant diseases of theanus and rectum. Intrarectal ultrasonogra-phy has demonstrated a high degree ofaccuracy in the assessment of extent oflocal invasion of rectal carcinomas as wellas the degree of regional lympadenopathy.It is also capable of detecting occultanorectal abscesses. In patients with fecalincontinence, it allows for the identifica-tion of sphincter defects. Defecography isa radiologic study in which thickened bar-ium is introduced into the rectum and thepatient is seated on a radiolucent commodeand instructed to evacuate contrast material.A video recording is taken in the lateralprojection. It is useful in evaluating patientswith obstructed defecation in an effort todetermine if patients have anismus, recto-cele, internal procidentia, or excessive per-ineal descent. Colonic transit studies requirepatients to ingest radiopaque markers whilereceiving a normal diet, without using lax-atives. Serial radiographs are taken atspecified intervals to determine the speedwith which the markers traverse the colon.A normal study should pass 80 percent ofthe markers by five days. If not, this issuggestive of colonic inertia. MR defecog-raphy with an open configuration magnetallows accurate assessment of anorectalmorphology and function in relation to sur-rounding structures without exposing thepatient to harmful ionizing radiation [56].

Minimally invasive techniquesThe field of laparoscopic colon and

rectal surgery has evolved slowly over thepast decade as compared to other laparo-scopic procedures. This is mainly due to thecomplexities of the procedures. Minimallyinvasive techniques can involve eitherabdominal procedures utilizing standardlaparoscopic instruments or approaches to

the rectum utilizing transanal endoscopicmicrosurgery. It is appealing for those whohave pulmonary disease, those who wouldbenefit from small incisions, and thosewho desire cosmesis. Almost every diseaseencountered in colon and rectal surgery isapproachable laparoscopically, however,colorectal cancer patients at this time arebest entered into a prospective randomizedtrial. Nevertheless, there remains a steeplearning curve due to the fact that colorectalsurgeons do little laparoscopy. Improve-ments in technology such as hand-assistedlaparoscopy have gained momentum.Regardless, it is estimated that the numberof colectomies performed by a totallylaparosopic, laparoscopically assisted, orhand-assisted laparoscopic technique isnationally less than 10 percent. There iscurrently some evidence that a minimallyinvasive approach may decrease postoper-ative ileus, requirements for postoperativeanalgesia, length of hospital stay, and cost.This is highly institutional dependent.Regardless minimally invasive approachesare attractive to patients with polypoidlesions of the colon not amenable to endo-scopic removal, functional disorders suchas rectal prolapse surgery, and selectpatients with inflammatory bowel disease,It would be premature to define its onco-logic benefit or risk in colorectal cancerprior to the maturity of currently undertak-en prospective randomized trials [57, 58].For any colorectal surgeon, its utility willdepend upon referral patterns and acuityand complexity of patients sees in theirdaily practice. It is doubtful that colorectalsurgery will be dominated by laparoscopy,but it will continue to have a role in properlyselected patients.

ROLE IN ACADEMIC MEDICINE

Resident and medical student education

Expertise by the educator often bringstremendous credibility to the learningenvironment. Currently, department chair-

74 Longo: The Specialty of Colon and Rectal Surgery

men are recruiting faculty with specializa-tion within general surgery in an effort tostrengthen not only surgical education butto grow practices and increase clinical rev-enues. Popular areas of specializationinclude minimally invasive surgery, surgi-cal oncology, endocrine surgery, and colonand rectal surgery. Within each of thesedisciplines "super specialization" withexposure, training, and experience in areassuch as laparoscopic morbid obesity surgery,inflammatory bowel disease, minimallyinvasive parathyroidectomy, soft tissuesarcomas, and pancreatic neuroendocrinetumors also lends further credibility. Fewpapers have been written regarding thebenefits of colon and rectal surgery to sur-gical education, but the advantages areobvious [59, 60]. Increased exposure ofuncommon and poorly understood proce-dures involving the anus, the small intes-tine as well as creation of low pelvic anas-tomoses with or without an intestinalreservoir has been elegantly reported [61,62]. Medical student exposure to surgery isa limited experience often involving threeto four months of a 48-month curriculum.When rotating on surgery, there is oftenheightened enthusiasm for "knife and gunclub surgery," the cerebral aspects of sur-gical critical care, and the removal of largetumors en-bloc with other contiguous organs.However, a medical student may be uncer-tain about the indications for surgical hem-orrhoidectomy, believe that all patientswith rectal cancer require an abdominoper-ineal resection, or perceive that womenwith fecal incontinence have nothing to beoffered other than a colostomy. As the spe-cialty of colon and rectal surgery trulyoffers the benefits of a complete specialty:a challenging office practice, sophisticateddiagnostic skills such as ultrasound andendoscopy, and a plethora of surgical pos-sibilities involving the abdomen, pelvis,and perineum, it serves as a good rolemodel of what a physician is all about.Furthermore one learns communicationskills, develops personality traits, and prac-

tices ethical behavior when confrontedwith the anxiety and at times the tragedy ofcolorectal cancer, the functional limita-tions of fecal incontinence or living with astoma, how disease can affect intimacyand personal relationships, and finally theeffect of disease as it occurs in the latestages of one's adult life.

Frontiers of research

Three principal areas that will continueto receive attention and funding in colorectaldisease include mechanisms of carcino-genesis and therapy, suppressing inflamma-tion and modulating inflammatory media-tors seen in intestinal inflammatory statessuch as Crohn's disease and ulcerative colitisand finally exploring mechanisms of intesti-nal motility and dysmotility as seen in irri-table bowel syndrome and poor functionalresults following operations restoringintestinal continuity. It is likely that themajority of the research efforts in colonand rectal disease will involve cancer. Thecontinuing advances being made in molec-ular biology will involve genetic profiling[63] resulting in identification of high-riskgroups (inherited colorectal cancer) Thiswill lend one to stratify an individual'srisk, develop alternative methods of detec-tion such as fecal DNA sampling in spo-radic cases, and bring about novel medicaltreatments involving biological therapiessuch as vaccines [64]. Angiogenesis appearsto have come to the forefront of colorectalcancer investigation with the realizationthat the growth of tumors is dependent onangiogenic factors [65]. Chemopreventioninvolving dietary supplements such as cal-cium and folic acid or the daily administra-tion ofcompounds that block critical enzymepathways implicated in carcinogenesissuch as cyclooxygenase continue to receiveattention [66]. Continued emerging surgicaltechnology will involve reducing surgicalstress and its potential immunologic con-sequences by utilizing surgical trauma.

Understanding the mechanisms of theinflammatory cascade and use of novel

Longo: The Specialty of Colon and Rectal Surgery 75

cytokine antagonists, growth hormone andcolon stimulating factors have and willcontinue to impact favorably in intestinalinflammatory states. Inflixamib (Remicaid)is a anti-tumor necrosis factor compoundwhich has had a major impact in refractoryfistulizing Crohn's disease involving theintestine and the anorectum. From thislandmark study, it is reasonable to assumethat other compounds will be developed toregulate the inflammatory cascade. This willclearly be aided by the further understandingof the molecular events that occur duringinflammation.

Surgeons with expertise in colon andrectal surgery are often called upon by theirmedical counterparts to evaluate patientswith a variety of functional bowel disor-ders often manifested by abdominal or pelvicpain, cramping, constipation, diarrhea andincontinence. The benefits of colectomyfor chronic constipation in highly selectedpatents and a combination of bowelretraining, biofeedback, and, where applic-able, anal sphincter repair for fecal incon-tinence have been well established.However, a tremendous amount of timeand healthcare resources have been uti-lized in patients with other functional dis-orders often with variable or unfavorableresults. Recent advances in the understand-ing of neurotransmitters and gut hormonesthat regulate intestinal physiology havecome to the forefront. After many years offailure of compounds such as cholinergicagonists and dopamine antagonists, highlyfocused research has directed physicians tolearn how to manipulate the serotoninergic(5-hydroxytryptamine-5HT) mechanismswithin the gut. A number of significantadvances including 5-HT3 antagonists fordiarrhea predominant irritable bowel and5-HT4 agonists for constipation irritablebowel have been met with favorableresults [67].

CONCLUDING REMARKS

Colon and rectal surgery is a true spe-cialty. Expertise can have a favorable impacton patients afflicted with afflictions of thecolon, rectum, and anus. It will impact favor-ably on patients who develop rectal cancerby both increased number of sphincter pre-serving procedures and decreased localrecurrence, increased the number and qual-ity of restorative procedures for ulcerativecolitis, offer alternatives for patients withdisabling fecal incontinence, result indiminished complications following surgeryfor benign anorectal disease and overalldiminish the number of patients whorequire an intestinal stoma. Within the aca-demic setting, the path is clearly paved fornovel and influential research initiatives inboth the basic sciences and translationalresearch. Its multifactorial role in education,character building and as a role model hasyet to be fully realized but will continue tocome of age.

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