( Rectal tumor )

S.A. Rooholamini, M.D., F. DeGregorio, M.D.*, M. Itani, M.S. VI, S. Saki, M.D., A. Matin, M.D., A.H. Au, M.D., G.C. Hansen, M.D., M.H. Lee, M.D., J. Rahimian, Ph.D., R.S. Saul, M.D., R.C. Verma, M.D.

 

From the Departments of Radiological Sciences and Pathology* at Olive View-UCLA Medical Center, Sylmar, CA

Citation Reference:  nairsociety.com/archives/02-07-2007case1004.htm

 

CASE SUMMARY

This is a 39-year-old man who presented with 9-month history of a painful mass in the posterior perineum originating from the anal region and extending into the base of the penis.  The mass is moderately painful and has been gradually increasing in size.  He has mild dysuria with no other urinary, gastrointestinal, or constitutional symptoms.  Specifically there is no nausea, vomiting, diarrhea, change in bowel habits, melena or hematuria.  The patient’s past medical history is unremarkable except for a motor vehicle accident with trauma to the left leg resulting in below knee amputation.  His family history is negative.  Patient is a social drinker, nonsmoker, and has no history of drug abuse.

On physical examination, a firm mass is palpable in the posterior aspect of the perineum on the right side.  The mass extends from the anus to the base of the scrotum, and measures approximately 6 cm.  On digital examination there are no mucosal lesions, but the mass is hard and tender on palpation.  Urinalysis is negative, and PSA level is 0.6.

 

RADIOLOGIC FINDINGS

An outside computed tomography (CT) of the abdomen and pelvis shows diffuse thickening of the wall of the rectum due to a mass measuring 6x5 cm in size, suggestive of a rectal neoplasm.  Transrectal ultrasound shows enlargement of the prostate with an abnormal contour and a hypoechoic cavity inside.  The wall of the cavity is thick and irregular.  A biopsy of the prostate was done.  A staging CT of the chest, abdomen, and pelvis shows a large soft tissue mass in the pelvic floor, measuring 8x7 cm, with a necrotic center.  The mass is contiguous with the anterior wall of the rectum and the base of the prostate, and extends into the perineum (figures 1-3).  There were small mediastinal, paraaortic and pelvic lymph nodes.

Figure 1.  Contrast enhanced axial CT image of the pelvis at the level of the base of the bladder shows a large mass in the region of the seminal vesicles and anterior aspect of the rectum.

 

Figure 2.  Contrast enhanced axial CT image of the pelvis at the level of the symphysis pubis shows a soft tissue mass with an area of low attenuation, probably due to necrosis.

 

Figure 3.  Contrast enhanced axial CT image of the pelvic floor demonstrates an abnormal soft tissue mass involving the anus and extending anteriorly into the base of the penis.

 

 

Continue to Diagnosis