10184-NQPC-7 Prognostic Significance of Preoperative Constipation in Patients with Malignant Glioma: Reproducibility Confirmed by External Validation

Abstract Objective Health-related quality of life (HRQoL) is a key indicator for evaluating the impact of disease and medical interventions on patients’ quality of life, measured through patient-reported outcomes (PROs). This study investigated the association between preoperative HRQoL and overall survival (OS) in patients with malignant glioma and conducted external validation for factors correlated with OS in the primary cohort. Methods Eighty-nine patients with malignant glioma (WHO grade 3 or 4) who underwent surgical treatment at the University of Tokyo Hospital or the National Cancer Center Hospital between February 2013 and May 2022 were enrolled as the primary cohort. Preoperative HRQoL scores were calculated for 26 items using the EORTC QLQ-C30/BN20. Univariate analyses were performed to assess associations between each item and OS, followed by multivariate analyses adjusting for age and pathological diagnosis. External validation was performed using an independent cohort of 54 patients treated at Kyorin University Hospital between March 2015 and June 2022. Results In the primary cohort, among the 26 HRQoL items, only preoperative “constipation” was significantly associated with OS. Patients with high constipation scores had a significantly shorter survival on Kaplan-Meier analysis (median survival: 32 vs. 89 months, P = 0.02). Multivariate analysis confirmed constipation as an independent negative prognostic factor (P = 0.0001, HR = 2.3, 95% CI: 1.5-4. 5). External validation showed that preoperative constipation remained a significant prognostic factor in both univariate (P < 0.0001) and multivariate analyses (P = 0.03, HR = 2.4, 95% CI: 1.1-5.1), reproducing the primary findings. Conclusion Although constipation is generally regarded as a minor symptom, this study demonstrates that it is the only preoperative HRQoL item independently associated with poor OS in patients with malignant glioma. These findings suggest that preoperative HRQoL, particularly constipation, may provide additional prognostic information beyond conventional clinical factors and offer new perspectives for prognostic models and treatment strategies.