Identifying chemotherapy benefits in high-risk patients with stage IB gastric cancer based on recurrence prediction...

This study aimed to identify high-risk patients with stage IB gastric cancer who were likely to benefit from adjuvant chemotherapy (AC) through a precise assessment of recurrence risk.

This multicenter, retrospective study analyzed patients with stage IB gastric cancer who underwent surgery between January 2010 and December 2021. High-risk factors (HR+) included poorly differentiated tumors, lymphovascular invasion, perineural invasion, or age <50 years, while those without were classified as negative (HR-). The Recurrence Prediction Value (RPV) was developed by weighting these factors.

Totally, 555 and 409 patients were included in the training and validation datasets, respectively. Using RPV, patients were stratified into three groups. The 3-year recurrence-free survival (RFS) rate for the HR+ with high RPV subgroup was lower than both the HR+ with low RPV and HR-with low RPV subgroups (training set: 86.7 % vs. 95.6 % vs. 98.4 %; all P < 0.001; validation set: 84.5 % vs. 94.0 % vs. 98.4 %; all P < 0.05). Subgroup analysis revealed that only the HR+ with high RPV subgroup benefited from AC, with significant RFS improvements (training set: AC vs. non-AC: 88.9 % vs. 83.9 %, P = 0.043; validation set: 92.2 % vs. 75.2 %, P = 0.003). A nomogram based on RPV for predicting recurrence demonstrated good calibration and discrimination, with C-index values of 0.748 and 0.711 for training and validation sets, respectively.

This study presents a method for identifying the benefit of chemotherapy in patients with stage IB gastric cancer based on RPV, which could assist surgeons in providing personalized treatment strategies for these patients.