A prospective study on the predictive value of the modified Glasgow prognostic score in non-small cell lung cancer treated with radiation therapy

This prospective observational study aimed to evaluate the prognostic value of the modified Glasgow prognostic score (mGPS), an inflammation- and nutrition-based index, in patients with non-small cell lung cancer (NSCLC) undergoing radiotherapy (RT) delivered with definitive-dose intent. Adults (≥ 18 years) with histologically or clinically confirmed NSCLC and Eastern Cooperative Oncology Group performance status 0–1 were enrolled. Pretreatment mGPS, derived from serum C-reactive protein (CRP) and albumin levels, was categorized as low (0) or high (1–2). Patients with stage 0–I disease received stereotactic body radiotherapy (SBRT), whereas those with stage II or higher underwent concurrent chemoradiotherapy or definitive RT alone. The primary endpoint was 2-year overall survival (OS); secondary endpoints were 2-year local control rate (LCR) and distant failure-free rate (DFFR). Between January 2021 and March 2023, 82 patients were analyzed (median age, 78 years; 70% treated with SBRT). With a median follow-up of 30.2 months (IQR 23.1–36.3), 2-year OS, LCR, and DFFR were 85.4%, 86.5%, and 80.1%, respectively. High mGPS was significantly associated with inferior OS (hazard ratio [HR] 5.71; 95% CI 1.96–16.66; p = 0.001), but not with LCR or DFFR. In the SBRT subgroup (n = 57), high mGPS remained a strong predictor of inferior OS (HR 7.15; 95% CI 1.73–29.61; p = 0.007). On multivariable analysis, high mGPS persisted as an independent prognostic factor in both the overall and SBRT cohorts. To our knowledge, this is the first prospective study to evaluate mGPS in NSCLC patients treated with RT, including SBRT. High mGPS independently predicted inferior OS in Cox regression analyses, highlighting the prognostic significance of host-related systemic inflammation and nutritional status. These findings support incorporating mGPS into pretreatment evaluation as a simple, objective biomarker to facilitate risk-adapted management and multidisciplinary decision-making in clinical practice.