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A case of advanced rectal adenocarcinoid tumor with long-term survival
Tomoyuki Wakahara1, Seiichiro Yamamoto, Shin Fujita
1Division of Colorectal Surgery, National Cancer Center Hospital, Tokyo, Japan.
Abstract:
Adenocarcinoid tumor most commonly occurs in the appendix and a tumor arising in the rectum is extremely rare. A 58-year-old man underwent total pelvic exenteration with extended lateral lymph node dissection for rectal adenocarcinoid tumor invading the urethra with lateral lymph node metastasis. Microscopically and immunohistochemically, the tumor consisted of carcinoid-like components and signet-ring-cell-carcinoma-like components, and an adenocarcinoid tumor was diagnosed. Postoperatively, the patient received combination chemotherapy of fluorouracil and leucovorin as an adjuvant therapy. Three years and 5 years after the initial surgery, the patient developed left groin and left external iliac lymph node recurrences, and lymphadenectomy was performed each time. As a result, the patient is alive more than 5 years after the initial surgery. There is no consensus on the indication of surgical treatment for adenocarcinoid tumor. However, in advanced cases, an aggressive surgical procedure might result in long-term survival when resectable.