A Case of Metastatic Penile Cancer from Colorectal Adenocarcinoma

Abstract

A 76-year-old man was diagnosed with adenocarcinoma of the rectum and received neoadjuvant radiotherapy (25 Gy/5 fr). After the start of radiotherapy, he underwent laparoscopic abdominoperineal resection (Lap-APR) with right side lateral lymph node dissection (ypT3N1bM0 ypStage IIIb). In addition to the surgery, he was given four cycles of postoperative adjuvant chemotherapy with CAPOX. Twenty months after the surgery, however, contrast-enhanced CT showed an abnormality in S7 of the liver, for which he underwent laparoscopic segmental liver resection. He then received seven cycles of adjuvant chemotherapy with capecitabine. At 43 months after the Lap-APR, a penile tumor was suspected because contrast-enhanced CT showed an abnormal high-density area in the left side of the penis. A biopsy of the corpus spongiosum showed adenocarcinoma, and based on the results of immunohistochemical (IHC) staining, he was diagnosed with metastatic penile cancer from colorectal adenocarcinoma. He decided to receive chemotherapy again with FOLFOX plus panitumumab, and tumor shrinkage was seen after six cycles of the chemotherapy.