Late Manifestation of Invasive Adenocarcinoma in a Right-Colon Interposition for Esophageal Atresia.

Colonic interposition is a recognized surgical technique for esophageal replacement in patients with esophageal atresia. While generally effective, this approach carries a risk of long-term complications, including the rare development of adenocarcinoma within the interposed segment. We present the case of a 59-year-old man with a history of esophageal atresia repaired in infancy using a right-sided colonic interposition. He presented for evaluation due to worsening dysphagia and early satiety. Endoscopic examination revealed a 20 mm ulcerated lesion at the distal anastomosis, and biopsy confirmed intramucosal adenocarcinoma. Fluoroscopic esophagram and PET-CT demonstrated a mass-like lesion with focal hypermetabolism but no evidence of metastatic disease. Given significant surgical risk due to prior abdominal surgeries and poor nutritional status, the patient elected to pursue systemic immunotherapy with close imaging and endoscopic surveillance. Adenocarcinoma arising in colonic interpositions is exceedingly rare, with latency periods typically ranging from 20 to 40 years. In this case, malignancy developed nearly six decades after the initial repair. This case highlights the potential for malignant transformation many decades after esophageal reconstruction and underscores the importance of sustained clinical follow-up and endoscopic surveillance in patients with colonic interpositions.