Application of Local Excision for Early Cancer of the Colon and Rectum
To confirm whether or not local excision for early cancer of the colorectum is sufficient to prevent recurrence, we attempted retrospectively to clarify the characteristics of such lesions and the criteria for additional resection following local excision. During a 22-year period (1974-1995), 184 (16.7%) of 1,103 patients (Dukes A: 286, B: 322, C : 290, D : 205) developed early colorectal cancer (m: 85, sm1 : 46, sm2 : 29, sm3 : 24). The number of patients who underwent resection was 114 (m: 47, sm1 : 32, sm2: 16, sm3 : 19). Twenty-five (m: 3, sm1 : 7, sm2: 10, sm3 : 5) underwent additional resection following local excision, and local excision was performed on 45 (m: 35, sm1 : 7, sm2: 3, sm3 : 0). Pathological findings revealed lymph node involvement in 11 cases, corresponding to 6.0% of the 184 early colorectal cancers and 7.9% of the 139 resected cases. Our results indicated that massive invasion of sm2 or sm3 (82%), the broad-based type of Is (64%), tumors greater than 20 mm in diameter (55%), and venous or lymphatic invasion (36%) including poorly differentiated adenocarcinoma (0%) were risk factors for lymph node metastasis. Therefore, additional resection following local excision is strongly recommended in the presence of any of these factors and a positive surgical margin. The rates of recurrence after resection, local excision and additional resection following local excision were 2 (1.8%) of 114 cases (cancer death: 2), 2 (4.4%) of 45 cases (cancer death: 1), and 0 (0%) of 25 cases, respectively.
