Effect of tumor size on prognosis in colorectal cancer.

Aim: This study aimed to reveal the effect of tumor size on overall survival and disease-free survival.

Material And Methods: This study retrospectively evaluated the data of 593 patients who underwent colorectal surgery for colorectal cancer (CRC) between May 2012 and December 2018. The patients were divided into two groups based on their tumor size; those with a tumor size <5 cm were grouped as group 1 and those with a tumor size ≥ 5 cm were grouped as group 2.

Results: The present study included 222 patients with colorectal adenocarcinoma. The median follow-up period of the patients was 36.0 (1.4-107.4) months, mean tumor size was 5.1±2.3 cm, and number of patients with a tumor size of ≥5 cm was 117 (52.7%). There were statistically significant differences between the groups in terms of overall survival (Log-Rank = 12.559, p<0.001).

Discussion: According to the American Joint Committee on Cancer's Cancer Staging Manual (8th edition), the CRC staging system considers the tumor's depth of invasion of the intestinal wall but not the tumor's size. Moreover, it considers the size of the tumors developing in the parenchymal organs (breasts and lungs) but not tumors developing in luminal organs (stomach, colon, etc.).

Conclusions: Tumor size ≥5 cm was found to be a risk factor for poor prognosis. To a certain extent, we believe that this study will aid in elucidating the link between tumor size in and prognosis of patients with CRC.

Key Words: Colorectal cancer, Prognosis, Tumor size.