Does tumor size have its prognostic role in colorectal cancer? Re-evaluating its value in colorectal adenocarcinoma with different macroscopic growth pattern.

BACKGROUND: Few previous studies have taken the growth pattern into consideration when analyzing the prognostic value of tumor size in colorectal cancer (CRC).

OBJECTIVE: We sought to reveal the prognostic role of tumor size in different macroscopic growth patterns of CRC.

MATERIALS AND METHODS: Using Cancer Center datasets, we identified 4057 cases with colorectal adenocarcinoma treated with curative resection. Macroscopic growth patterns of tumors were classified into three types: infiltrative, ulcerative and expansive types based on tumor gross appearance. Univariate and multivariate Cox regression analyses were performed to evaluate the prognostic factors for overall survival (OS) and disease-free survival (DFS).

RESULTS: In whole cohort, tumor size was an independent factor for OS (HR 1.10, 95%CI 1.04-1.16, p < 0.001). Subgroup analysis based on macroscopic growth pattern suggested that tumor size was an independent factor for OS both in the infiltrative (HR 1.37, 95%CI 1.12-1.66, p = 0.002) group and ulcerative group (HR 1.08, 95%CI 1.00-1.16, p = 0.044) and tumor size (HR 1.22, 95%CI 1.06-1.40, p = 0.004) was found as an independent factor for DFS only in infiltrative group.

CONCLUSIONS: Tumor size is an independent factor for OS and DFS in patients with colorectal adenocarcinoma of infiltrative type, while only for OS in patients of ulcerative type.