Spread of prostate carcinoma to the perirectal lymph node basin: analysis of 112 rectal resections over a 10-year span for primary rectal adenocarcinoma.

We recently identified metastatic prostate carcinoma (PCA) within perirectal lymph nodes (PLNs) from 2 patients undergoing abdominoperineal resection (APR) for rectal adenocarcinoma (RA). As this phenomenon has not been addressed by any studies in the literature and because these positive PLNs had the potential to be mistakenly diagnosed as metastatic RA, we were prompted to undertake a retrospective study of rectal resections for RA to determine the frequency of PCA metastasizing to the PLNs in this patient population. The laboratory information system of the Department of Pathology, Capital Health, Halifax, Nova Scotia was searched for lymph node (LN)-positive RAs resected by low anterior resection or APR in male patients between January 1, 1992 and December 31, 2002.