Giant multilocular prostatic cystadenoma: a distinctive lesion of the retroperitoneum in men. A report of two cases.

Two examples of large, multiloculated, cystic tumors that arose within the pelvis in men of 28 and 37 years of age are described. The tumors were composed of glands and cysts lined by prostatic-type epithelium lying in a hypocellular fibrous stroma. The prostatic nature of the lesions was confirmed by immunohistochemical staining of the epithelium for prostate-specific antigen and prostatic acid phosphatase. Two apparently similar lesions were found in the literature; one tumor was attached to the prostate by a pedicle, and the other arose in the retrovesical space. These tumors, for which we propose the designation "giant multilocular prostatic cystadenoma," appear to be benign, although they may recur if incompletely excised. They may pose considerable diagnostic difficulty if the prostatic nature of the epithelium is not appreciated, an error that is likely if a relationship to the prostate is not recognized. This lesion should be included in the differential diagnosis of retroperitoneal cystic tumors in men.

Construction of an omental envelope as a method of excluding the small intestine from the field of postoperative irradiation to the pelvis.

A technique for excluding the small intestine from the true pelvis in order to permit high dose radiotherapy is described herein. The procedure is done postoperatively after incomplete resection for carcinoma of the colon and rectum.

Elective postoperative radiotherapy after incomplete resection of colorectal cancer.

It is known that patients with incompletely resected epithelial cancers are at high risk of local recurrence. A prospective study to determine whether elective postoperative radiotherapy can decrease the incidence of local recurrence and thus improve survival of those patients with an incompletely resected tumor was made of 125 irradiated patients with locally advanced colorectal cancer (B2, C1, C2) 78 patients had rectosigmoid tumors and 47 had colonic cancers. Complete resection (R0) was performed in 94 patients (75 per cent). Thirteen (10 per cent) had microscopic (R1) and 18 (14 per cent) had gross residual disease (R2). Local control and survival (average follow-up, 38 months) of patients with microscopic residual cancer (RI) were 84 per cent (11/13) and 77 per cent (10/13) respectively. These results were identical to those obtained in patients without residual disease (R0). Patients with gross residual disease (R2) had a local control of 50 per cent (9/18) and a survival of 39 per cent (7/18). Radiation complication occurred in seven of 125 patients (6 per cent). One patient died, of radiation enteritis. One patient required a nephrostomy. The remaining five patients were treated conservatively. Elective postoperative radiotherapy given to patients who had incomplete resection of a colorectal cancer prevented local recurrence in the majority and may have increased survival.