Xinlian Du ¹ Xinxin Zang ^1* Hanbo Zhang ^1* Lijia Liu ^1,2* Ying Xu ^1* Xuedong Li ^1* Ruishu Mou ^1* Haitao Xu ^1* Jiuxin Zhu ^2* Rui Xie ^1*

• ¹ Harbin Medical University Cancer Hospital, Harbin, China
• ² Harbin Medical University, Harbin, Heilongjiang, China

The aim of this study is to compare mean platelet volume to platelet count ratio (PVPR) and other indicators' predictive abilities. Simultaneously a new nomogram for predicting recurrence free survival (RFS) after gastrointestinal stromal tumors (GISTs) R0 resection was developed.Methods: From January 2010 to July 2019, 295 GISTs patients who were operated on at Harbin Medical University Cancer Hospital were retrospectively reviewed. With a 4-year RFS as the endpoint, using the Kaplan Meier methods and log rank test, and then conducting Cox regression analysis, we compared and identified meaningful indicators for predicting prognosis. Finally, a nomogram was developed and validated using calibration curves.The ROC curve indicated that a cut-off point of 0.044 was the ideal threshold for PVPR, and patients were divided into a high PVPR group (≤ 0.044) and a low PVPR group (>0.044). Kaplan-Meier curves suggested that PVPR＞0.044 had obvious associations with better RFS ( p ＜ 0.001). In accordance with multivariate analysis, PVPR (＞0.044 vs. ≤0.044) (p=0.005), NIH risk category (p＜0.001), Ki-67 (p=0.005) were independent prognostic indicators of RFS. Tumor size, gastrointestinal bleeding, mitotic index, NIH risk category, CD34, and Ki67 all exhibited an elevated obvious correlation with PVPR (all p <0.05). The nomogram's probability of concordance was 0.823, indicating that the nomogram predictions were well-calibrated.In GISTs, RFS can be independently predicted by PVPR. Patients with higher PVPR have better RFS. The nomogram including PVPR could be used to assist clinical treatment decision-making.