Figure 2.

The optimal cut-off value of preoperative circulating tumor size in the Surveillance, Epidemiology, and End Results Cohort (SEER) database of 16,283 patients with stage IV colorectal cancer using X-tile software. (A) The data are presented as a right triangle grid graph, where each point represents a set of data for a given partition and the optimal cut-off point is highlighted by a black circle. (B) The cut-offs of tumor size are 46 (mm) and 66 (mm), and patients were divided into three groups by locating the brightest pixels on the X-tile. Given the clinical application of tumor size, we rounded up the data and divided tumor sizes into <50, 50–69, and ≥70 mm. (C) Kaplan–Meier curves show overall survival of three groups (<50, 50–69, and ≥70 mm).