A rare case of metastatic pancreatic adenocarcinoma initially diagnosed in a rectal prolapse repair specimen post Altemeier's procedure.

Abstract

Introduction: An 81-year-old male presenting for rectal prolapse repair, with a background of a recently diagnosed pancreatic mass. Case description: An 81-year-old-male, with a recent incidental finding of a pancreatic mass, underwent an elective redo Altemeier's procedure for recurrent rectal prolapse. Histopathology of rectal tissue showed two small, angulated glands within subserosa and further levels revealed multiple atypical glands. The patient's history of likely pancreatic cancer was initially unknown, though after discussion with the treating team immunohistochemistry was performed which was suggestive of metastatic pancreatic adenocarcinoma (CK7+, CDX2 patchy +, CK20-, calretinin-, TTF1-, NKX3.1-, SATB2-). Discussion(s): Pancreatic cancer is the fourth most common cause of cancer death in Australia and has a 5-year survival rate of 13%.1 Metastasis is common, particularly to liver, peritoneum, lung, bones, and adrenal glands.2 Metastasis to the rectum is incredibly rare, however, with only one published case report.3 For this reason, as well as the lack of clinical information available to the pathologist at the time, metastatic pancreatic cancer was not initially considered. This case emphasises the value of acquiring clinical history as well as seeking advice from colleagues and reviewing further levels when faced with a difficult case or rare entity. References 1. Australian Government, Cancer Australia. Pancreatic Cancer in Australia Statistics. 11 Mar 2024. https://www.canceraustralia.gov.au/cancer-types/pancreatic-cancer/statistics [accessed 25 Nov 2024]. 2. Yachida S, Iacobuzio-Donahue CA. The pathology and genetics of metastatic pancreatic cancer. Arch Pathol Lab Med 2009; 133: 413-22. 3. Sun J, Zhang X, Huang H, et al. Rectal metastasis from a previously resected carcinoma of the pancreas: a case report. Transl Cancer Res 2020; 9: 3018-23.Copyright © 2024