Renal cyst

CASE PRESENTATION

BYDr. Muhammad SaifullahPG Trainee, Department of Urology, AHF

INTRODUCTIONMr. X.Y.Z , 48 years old, married &

resident of Batala colony, Faisalabad was admitted via OPD with the presenting complaint of

Pain Right Lumbar Region – 9 months Swelling Right Lumbar Region – 3

months

HISTORYThe patient was in usual state of health 9

months back when he experienced gradual onset mild pain over the Right lumbar region. This pain was dull in nature, radiated to the back and was not associated with fever, vomiting or hematuria. This pain was non-progressive, aggravated by itself & was relieved by oral medication (No record available)

6 months later, he noticed swelling over the Right lumbar region when he was taking bath. The swelling was initially small but was gradually progressive. This swelling was also not associated with fever, vomiting or hematuria.

PAST HISTORY No history of any previous similar episode. Known case of Heart disease – 20 years History of Appendectomy – 15 years History of open reduction and internal

fixation of Left Radius & Ulna – 10 years

FAMILY HISTORY

•No family history of DM, HTN, TB or IHD.

•Both parents alive and healthy.

Govt. Employee. Smoker – 30 years. Middle socio-economic class.

SOCIAL HISTORY

GENERAL PHYSICAL EXAMINATION

A middle aged man of average built lying comfortably on the couch with following vitals:

Pulse…. 88/min BP…. 110/70 R/R…. 16/min Temp…. 98.6 oF

NAILS…No Pallor, clubbing, koilonychia, splinter hemorrhages or cyanosis.

FINGERS… No Osler’s, Heberden’s or Bouchard’s nodes, Joint swelling or deformity.

PALM… No sweating, palmar erythema or dupuytren’s contracture.

FACE… No puffiness, proptosis, jaundice, xanthelasmas or central cyanosis. Good oro-dental hygiene.

NECK… No thyroid swelling, engorged neck veins or palpable cervical lymph nodes.

FOOT… No edema, cyanosis or loss of hair.

ABDOMINAL EXAMINATION Abdomen scaphoid with normal shaped

umbilicus, central in position. Peristalsis not visible. Fullness of Right Lumbar region. No visible scars, striae or veins. Hernial orifices are intact.

Abdomen was soft and non-tender. A cystic non-tender mass palpable occupying the Right lumbar region which was not reducible or compressible. Kidneys billaterally not palpable. No visceromegaly.

Abdomen was resonant on percussion except right lumbar region where dullness was present. No Shifting dullness.

Bowel sounds 2-3 per minute with no audible bruits or succussion splash.

DRE. Normal Rest of the examination was unremarkable.

INVESTIGATIONS HB 14.3 mg/dl E.S.R 12 after 1st hour T.L.C 7,700 neutrophils 79 % lymphocytes 16 % monocytes 03 % eiosinophills 03 %

Platelets count 1,28,000

R.B.S 96

Urea 44 mg/dl Creatinine 0.7 mg/dl

Billirubin total 0.8 SGOT(AST) 38 Alk phosphatase 211

HbsAg ---> neg Anti Hcv ---> neg

ECG

Echocardiography

Ultrasound KUB

Cystogram

CT Scan KUB with contrast

LITERATURE REVIEW

OUTLINE Introduction Simple Cysts Differentials Complex/Complicated Cysts BOSNIAK Classification Management according to BOSNIAK

Categories

CYSTA cyst is a closed sac, having a distinct

membrane and division compared to the nearby tissue.

Cyst is a Greek word meaning “Fluid Filled Sac”

It may contain  Air Fluids Semi-solid material

If this cavity lacks a distinct membrane, it is called PSEUDOCYST.

If it is filled with pus, it is called an ABSCESS.

RENAL CYST A renal cyst is

a fluid collection in the kidney.

27-35 % of individuals greater than 50 years of age may have asymptomatic simple renal cysts.

Prevalence increases with increasing age and by the age of 70 years almost every person has a simple renal cyst.

SIMPLE CYSTS Simple cysts arise from

obstructed tubules or ducts. They do not communicate

with collecting system. Commonly asymptomatic

Hematuria (from cyst rupture) Infection (Abscess) Mass effect from large cysts

may cause dull ache or discomfort.

HYPERDENSE CYSTA hyperdense cyst a simple kidney cyst

that has blood as part of the contents of the cyst.

A hyperdense kidney cyst is not suspicious for kidney cancer and is just another type of simple kidney cyst.

Intravenous Urography A lucent mass may be seen within the renal

parenchyma. A "claw" sign may be seen if the cyst

extends beyond the surface of the kidney, and represents the adjacent stretched parenchyma. If the cyst is completely intrarenal, the thickness of its wall cannot be assessed.

Radiographs taken 1-2 minutes after IV contrast injection optimally visualize a cyst. 

Lucent defect

Cortical bulge

Round indentations on collecting system

"Beak sign" can be seen with large cysts.

Radiographic features , US:

Anechoic

Enhanced through-transmission

Sharply marginated,smooth walls

Radiographic features , CT:

Smooth cyst wall

Sharp demarcation

Homogenous Water density (< 10-15 HU)

No significant enhancement after IV contrast (<5HU)

Cyst wall too thin to be seen by CT

Be Careful:

Cysts that contain calcium, septations, and irregular margins (complicated cysts) need further workup

True renal cysts should always be differentiated from hydronephrosis, calyceal diverticulum, and peripelvic cysts.

Differentiate renal cyst from hypoechoic renal artery aneurysm using color Doppler US and Angiography

Hydronephrosis:

Calyceal Diverticulum

Parapelvic Cyst

Renal Artery Aneurysm

Complicated CYSTSComplicated cysts are cysts that do not meet the criteria of simple cysts and thus require further workup.

• Internal debris• Echogenic clot• Fluid-debris levels• Thick septations• Thick walls• Thick or coarse calcification

Increased CT density (> 15 HU) of cyst contentVast majority of these lesions are benign.High density is usually due to hemorrhage, high protein content, and/or calcium.

Radiographic Features of Complicated CystsSeptationsThin septa within cysts are usually benign.Thick or irregular septa require workup.

CalcificationsThin calcifications in cyst walls are usually benign.Milk of calcium: collection of small calcific granules in cyst fluid: usually benign

Thick wallThese lesions usually require surgical exploration.

BOSNIAK CLASSIFICATION of

RENAL CYSTS

BOSNIAK Category I

Benign simple cyst with:

Thin wall without septa No calcifications No solid components No contrast enhancement. Density equal to that of water

Simple renal cyst, Bosniak Category I.

BOSNIAK Category II

Benign cyst with

A few thin septa May contain fine calcifications Homogenous lesions less than 3 cm

with sharp margins Without enhancement

Bosniak Category II cyst

Curvilinear calcification within a thin septum

Bosniak Category II cyst

Homogeneously hyperdense mass No increase in Density after IV contrast

Bosniak Category II cyst

Cyst with several internal septations and a minimally thickened wall

Bosniak Category II cyst.

Cyst with uniform, mild wall thickening and short, interrupted calcifications

Bosniak Category II hyperdense cyst.

Bosniak Category II cyst

Bosniak Category II cyst.

Nearly completely calcified mass with no obviousenhancing elements

Bosniak Category II.

subcentimeter rim calcified renal cyst

BOSNIAK Category IIFWell marginated cysts with

A number of thin septa, with or without mild enhancement or thickening of septa.

Thick and nodular calcifications may be present

No enhancing soft tissue components Non enhancing lesions 3 cm or larger.

BOSNIAK Category IIF

BOSNIAK Category III

Indeterminate cystic masses with

thickened irregular septa with enhancement.

multilocular, encapsulated mass

Increase in Hounsfield Units of the mass after contrast injection….. ENHANCEMENT(>15% = enhancement = surgical on MRI)

Bosniak Category III.

cystic mass with irregular wall thickening andassociated heterogeneous nonenhancing elements

Bosniak Category III complex cyst.

multilocular, encapsulated mass

Bosniak Category III complex cyst.

Thick-walled, encapsulated, multilocular cystic mass with enhancing septa

BOSNIAK Category IV

Malignant cystic masses with All the characteristics of category III

lesions Enhancing soft tissue components

independent of but adjacent to the septa.

Bosniak Category IV cystic neoplasm.

Bosniak Category IV cystic neoplasm

A 42-year-old female with back pain, hematuria, and a renal mass discovered by lumbar spine MR. hyperdense (55 HU) 3 cm mass.

enhance to 88 HU after IV contrast

Renal cell carcinoma

BOSNIAK CLASSIFICATIONCategory (Bosniak) US Features Workup

Type 1: Simple cyst Round, anechoic, thin wall enhanced through transmission

None

Type 2: Mildly complicated cyst

Thin septation, calcium in wall

CT or US follow-up

Type 3: Indeterminate lesion

Multiple septae, internal echos mural nodules

Thick septae

Partial nephrectomy, biopsy

CT follow-up if surgery is high risk

Type 4: Clearly malignant

Solid mass component Nephrectomy

To identify size criteria for complex cystic renal masses that can distinguish renal cell carcinoma from benign cysts supplementing the Bosniak classification

To identify size criteria for complex cystic renal masses that can distinguish renal cell carcinoma

from benign cysts supplementing the Bosniak classification

To identify size criteria for complex cystic renal masses that can distinguish renal cell carcinoma

from benign cysts supplementing the Bosniak classification

Malignancy was significantly associated with 1.cyst size (>2 cm)2.male gender3.younger patient age (<50 years).

According to the Bosniak classification, no category I cystall 8 category II cysts were benign3 of 18 (17%) category IIF cysts were malignant21 of 39 (54%) category III cysts were malignant29 of 32 (90%) category IV cysts were malignant.

All category IIF cysts were benign in patients older than 50 years of age

TreatmentTreatment is not needed for asymptomatic simple

kidney cysts.  Simple kidney cysts may be monitored with periodic

ultrasounds. Simple kidney cysts that are causing symptoms or

blocking the flow of blood or urine through the kidney may need to be treated using a procedure called sclerotherapy.

If the cyst is large, surgical excision may be needed.

In SCLEROTHERAPY, the doctor punctures the cyst using a long needle inserted through the skin. Ultrasound is used to guide the needle to the cyst. The cyst is drained and then filled with a solution containing alcohol to make the kidney tissue harder. The procedure is usually performed on an outpatient basis with a local anesthetic.

MANAGEMENTIgnore, Follow or Excise

Renal cysts can be classified according to the Bosniak classification depending on their features. 

Type I cysts are simple cysts.Type II are the minimally complicated cysts. Type I and II can be ignored. 

Type II F are probably benign, but need to be followed. 

Type III and IV both are surgical lesions. 

Type IV is inevitably malignant and in the type III group about 80-90% turn out to be malignant as well

ANY QUESTIONS ??????