Can horizontal diameter of colorectal tumor help predict prognosis?

We aimed to investigate the relationship between the horizontal tumor diameter and prognosis.

Patients' records were analyzed retrospectively. Patient data, including age, gender, vertical penetration, anatomic location, differentiation of the tumor, tumor node metastasis (TNM) stage, survival rate, and disease-free survival, were analyzed to find out if there was any correlation with horizontal tumor diameter.

A total of 439 colorectal cancer patients were enrolled. Patients were stratified into two groups according to the horizontal tumor diameter (≤4.5 cm vs. >4.5 cm). Poorly differentiated tumors were significantly larger than other differentiation groups (p=0.003). The horizontal diameter increased with increase in T-stage (p<0.001). Similarly, the number of positive lymph nodes increased significantly as the size of the horizontal tumor diameter increased (p<0.001). The relationship between TNM staging and the horizontal diameter of tumors in both groups was examined, and it was found that the progression of tumor stage was accompanied by increased horizontal diameter (p<0.001). It was also found that the horizontal tumor diameter was not correlated with local recurrence (p=0.063). However, distant metastasis was higher in patients with a tumor larger than 4.5 cm (p=0.02). Although the disease-free survival was shorter in patients with a horizontal tumor diameter more than 4.5 cm, the difference was not statistically significant.

There is a significant relation between horizontal diameter of the tumor and depth of the tumor, lymph node involvement, overall survival, and distant metastasis. Horizontal diameter of the tumor can possibly be used as a prognostic factor in colorectal cancer patients.