# A Solitary Duodenal Metastasis from Transverse Colon Cancer Detected Six Years after Curative Resection: A Case Report

## TL;DR

A rare case of colon cancer recurring as a solitary duodenal metastasis six years after initial surgery is reported and successfully treated.

## Contribution

This case report highlights an extremely rare instance of isolated duodenal metastasis from colon cancer detected years after curative resection.

## Key findings

- A 79-year-old male had a solitary duodenal metastasis from transverse colon cancer detected six years after initial surgery.
- The patient underwent successful R0 resection of the metastasis and remained recurrence-free for two years post-surgery.
- The case underscores the possibility of late recurrence in colon cancer patients despite initial curative treatment.

## Abstract

Recurrence of colon cancer after 5 years or longer from primary surgery is relatively rare and furthermore, isolated metastasis to the duodenum is extremely rare.

The patient was a 79-year-old male. He underwent laparoscopic partial colectomy with radical lymphadenectomy for transverse colon cancer. Pathohistological examination revealed that the tumor stage was T4aN0M0, resulting in R0 resection. An oral adjuvant chemotherapy was administered only one course due to side effects. The serum carcinoembryonic antigen level began to increase after 5 years and 1 month postoperatively. An upper gastrointestinal endoscopy at 6 years postoperatively revealed a submucosal tumor at the inferior duodenal angle, and subsequent endoscopic ultrasound-fine needle aspiration confirmed the diagnosis of duodenal metastasis from transverse colon cancer. As no other metastatic lesion was detected, open partial duodenectomy was undergone and R0 resection was achieved. The patient has been under regular follow-up without adjuvant chemotherapy and has survived without recurrence for 2 years since the second surgery.

Although extremely rare, the possibility of isolated duodenal recurrence after surgery for colon cancer exists. With a brief review of the literature, we report here a rare recurrence case of transverse colon cancer which was discovered at 6 years postoperatively and resulted in curative resection.