Evaluating the Khorana risk score of gastrointestinal cancer patients during initial chemotherapy as a predictor of patient mortality: A retrospective study

Background The Khorana risk score (KRS) has been recommended for predicting the incidence of cancer-associated thrombosis (CAT). However, it has been reported KRS was not useful in predicting CAT, but rather in predicting death by setting high scores for the primary tumor site or a low prevalence of severe obesity. Methods A total of 260 consecutive patients with no history of thrombosis and who started initial chemotherapy for gastrointestinal cancer from January 2017 to December 2018 at our hospital were divided into three groups according to KRS; they were observed until December 2019 [122 patients (46.9%) in the low-risk group, 114 patients (43.8%) in the intermediate-risk group, and 24 patients (9.2%) in the high-risk group]. The incidence of CAT and all-cause death were compared among the three groups. Results The median age of the patients was 67 years; 63.5% were men. CAT was observed in 61 patients (26.1%); 84 patients (37.9%) died during the observation period. The incidence rate of CAT was similar among the three groups (log-rank p = 0.4); but all-cause death showed a significant difference among the three groups (high-risk group: 58.2%, intermediate-risk group: 44.6%, low-risk group: 27.5%, log-rank p = 0.002). In the multivariate analysis, the high-risk KRS group remained at increased risk for all-cause death (HR, 2.83; 95% CI, 1.37–5.83; p = 0.005), but not with CAT. Conclusions The KRS at the start of chemotherapy for gastrointestinal cancer is not effective in predicting CAT, but it is effective in predicting prognosis in patients with gastrointestinal cancer.