Abstract
BACKGROUND: We report an exceptionally rare case of a solitary esophageal metastasis occurring in the tenth year after curative resection of stage I (pT2N0M0) rectal adenocarcinoma. This represents one of the longest reported intervals to esophageal metastasis from colorectal cancer, challenging the conventional understanding of metastatic potential of early-stage tumors. CASE SUMMARY: A 42-year-old male underwent curative resection for rectal adenocarcinoma (pT2N0M0, stage I) in 2015. Ten years later (2025), he presented with progressive dysphagia. Imaging and endoscopy revealed a mid-esophageal tumor with mediastinal lymphadenopathy. Initial biopsy suggested primary esophageal adenocarcinoma. After two cycles of neoadjuvant immunochemotherapy, dysphagia worsened. However, a multidisciplinary team re-evaluation, utilizing comparative immunohistochemistry for the esophageal lesions and rectal specimens, confirmed the diagnosis as a solitary esophageal metastasis from rectal adenocarcinoma (RAS wild-type). The patient received involved-field radiotherapy with concurrent systemic therapy (capecitabine, oxaliplatin and cetuximab). Dysphagia significantly improved one week after radiotherapy initiation. Three-month follow-up imaging after radiotherapy demonstrated a partial response. The patient was on cetuximab maintenance. CONCLUSION: This case underscores the risk of early tumor recurrence or metastasis beyond standard follow-up windows thus long-term follow-up is necessary.