Fig. 1From: Negative lymph node count is an independent prognostic factor for patients with rectal cancer who received preoperative radiotherapyX-tile analysis of survival data from the SEER registry. X-tile analysis was performed using patient data, equally divided into training and validation sets, from the SEER registry. In X-tile plots of the training sets (a), the plots of matched validation sets are shown in the smaller inset. The optimal cut-point highlighted by the black circle (a) is shown on a histogram of the entire cohort (b), and a Kaplan-Meier plot (c). P values were determined using the cutoff point defined in the training set and applying it to the validation set. (The optimal cutoff value for NLN count is 9, χ2 = 78.060, P < 0.001)Back to article page