Barium Enema Barium Enema in the detection of in the detection of

Colon CancerColon Cancer

Radiology Rotation PresentationRadiology Rotation Presentation

Karen JoyntKaren Joynt

November 25, 2003November 25, 2003

Case HistoryCase History

Mr. J. is a 68 yo African-American maleMr. J. is a 68 yo African-American male

Presents for routine colon cancer Presents for routine colon cancer screening, urged by his sister, whose screening, urged by his sister, whose husband recently passed away due to husband recently passed away due to colon cancercolon cancer

Asymptomatic; no h/o GI bleed, no Asymptomatic; no h/o GI bleed, no constipation, no diarrheaconstipation, no diarrhea

Case History, continuedCase History, continued

PMHx: HTN, asthma in childhood, goutPMHx: HTN, asthma in childhood, gout

SocHx: lives with wife, retired engineerSocHx: lives with wife, retired engineer

Allergies: NKDAAllergies: NKDA

Meds: Norvasc, aspirinMeds: Norvasc, aspirin

Presents for routine screening, via barium Presents for routine screening, via barium enemaenema

Barium EnemaBarium Enema

Bowel preparation the night beforeBowel preparation the night before

Three stages: filling with barium, gas Three stages: filling with barium, gas insufflation, and radiography insufflation, and radiography

Smooth-muscle relaxant (20 mg of Smooth-muscle relaxant (20 mg of buscopan or 0.5–1 mg of glucagon) can buscopan or 0.5–1 mg of glucagon) can be utilized to decrease crampingbe utilized to decrease cramping

Requires considerable patient cooperation Requires considerable patient cooperation and mobilityand mobility

Radiographic Findings: NormalRadiographic Findings: Normal

Radiographic Findings: NormalRadiographic Findings: Normal

Radiographic Findings: PolypRadiographic Findings: Polyp

Radiographic Findings: PolypRadiographic Findings: Polyp

Colon PolypsColon Polyps

Most colorectal CA arises from adenomatous Most colorectal CA arises from adenomatous polyps; progression generally takes >10 yearspolyps; progression generally takes >10 years2/3 of polyps are adenomas; prevalence of 2/3 of polyps are adenomas; prevalence of adenomas is 25% by age 50 and 50% by age 70adenomas is 25% by age 50 and 50% by age 70Hyperplastic polyps account for the remaining Hyperplastic polyps account for the remaining 1/3 and do not generally progress1/3 and do not generally progressCurrent recommendations are that all adults Current recommendations are that all adults over 50 should be screened for colon cancerover 50 should be screened for colon cancerLess than 40% of Americans for whom Less than 40% of Americans for whom screening is indicated receive itscreening is indicated receive it

DCBE vs. the othersDCBE vs. the others

DCBE detects half of adenomas larger than 1.0 DCBE detects half of adenomas larger than 1.0 cm and 39 percent of all polypscm and 39 percent of all polypsAbnormalities must be followed by colonoscopyAbnormalities must be followed by colonoscopyFalse positives from retained stool, air, and other False positives from retained stool, air, and other causes of mucosal irregularity causes of mucosal irregularity Advantages: entire colon, relatively safeAdvantages: entire colon, relatively safeNo studies evaluating effectiveness of DCBE in No studies evaluating effectiveness of DCBE in the prevention of CRC deaths the prevention of CRC deaths (note: DCBE identifies lesions better than FOBT, (note: DCBE identifies lesions better than FOBT, which has been shown to lower CRC mortality) which has been shown to lower CRC mortality)

DCBE vs. the others, continuedDCBE vs. the others, continued

Other screening options include Other screening options include FOBT yearly (cheap, but only 2% true-positive, FOBT yearly (cheap, but only 2% true-positive,

doesn’t detect most polyps)doesn’t detect most polyps) Sigmoidoscopy every 5 years (more expensive, can Sigmoidoscopy every 5 years (more expensive, can

see only half of the colon)see only half of the colon) Colonoscopy every 5-10 years (most expensive, most Colonoscopy every 5-10 years (most expensive, most

complications, but most sensitive and specific) complications, but most sensitive and specific)

No obvious winner in cost-effectivenessNo obvious winner in cost-effectiveness

Final decision depends on patient preferencesFinal decision depends on patient preferences

ReferencesReferences

Grainger & Allison's Diagnostic Radiology: Grainger & Allison's Diagnostic Radiology: A Textbook of Medical Imaging, 4A Textbook of Medical Imaging, 4thth Edition, Edition, 2001 2001

UpToDate: uptodateonline.com, UpToDate: uptodateonline.com, “Screening for colorectal cancer”“Screening for colorectal cancer”