Long-term outcomes after treatment for T1 colorectal carcinoma: a multicenter retrospective cohort study of Hiroshima GI Endoscopy Research Group.

ABSTRACT

BACKGROUND: We aimed to clarify the long-term outcomes of patients with T1 colorectal carcinoma (CRC) after endoscopic resection (ER) and surgical resection. METHODS: We examined T1 CRC patients treated during 1992-2008 and who had ≥5 years of follow-up. Patients who did not meet the curative criteria after ER according to the Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines were defined as "non-endoscopically curable" and classified into three groups ER alone (Group A 121 patients), additional surgery after ER (Group B 238 patients), and surgical resection alone (Group C 342 patients). Long-term outcomes and predictors of recurrence were analyzed. RESULTS: Of the 882 patients with T1 CRC, 701 were non-endoscopically curable. Among these patients, recurrence and 5-year overall survival (OS) rates were 0.6 and 91.1%, respectively. In Groups A, B, and C, recurrence rates were 5.0, 5.5, and 3.8%, OS rates were 79.3, 92.4, and 91.5% (p < 0.01), and 5-year disease-free survival (DFS) rates were 98.1, 97.9, and 98.5%, respectively. Thirty-two patients experienced local recurrence or distant/lymph node metastasis (Group A 6; Group B 13; Group C 13) and 14 patients died of primary CRC (Group A 3; Group B 7; Group C 4). Age ≥65 years, protruded gross type, positive lymphatic invasion, and high budding grade were significant predictors of recurrence in non-endoscopically curable patients. CONCLUSIONS: Our findings supported the JSCCR criteria for endoscopically curable T1 CRC. ER for T1 CRC did not worsen the clinical outcomes of patients who required additional surgical resection.