LOW TEMPORAL MUSCLE MASS MAY BE A NEGATIVE PREDICTIVE AND PROGNOSTIC MARKER IN PATIENTS WITH GLIOBLASTOMA TREATED WITH CONCURRENT CHEMORADIOTHERAPY

Abstract

Sarcopenia (low muscle mass) is a syndrome associated with poor outcome in cancer patients. Temporal muscle thickness (TMT) is a novel biomarker of sarcopenia, however there is no detailed research to establish its significance in patients with glioblastoma multiforme (GBM). We investigated the prognostic and predictive performance of TMT measured on brain MRIs in patients with primary GBM, treated with concurrent chemoradiotherapy with temozolomide (TMZ). Material and methods: Data of 57 patients with primary GBM grade IV who were not feasible for total resection were retrospectively analyzed between November 2016 and April 2021. All patients were treated with subtotal resection (STR) or open biopsy and after that with concurrent chemoradiotherapy with TMZ. TMT was measured bilaterally on axial thin slice (1 mm cut) contrast-enhanced T1-weighted MRI images perpendicular to the long axis of the temporal muscle at the level of the orbital roof before to start with treatment. The axial MR plane was oriented parallel to the anterior commissure – posterior commissure line. The median value of TMT (15.2 mm) was used to divide patients into patients with or without sarcopenia. Results: The cohort included 35 men (61.4%) and 22 women (38.6%), with a total mean age of 54.1 ± 8 years. Patients with Eastern Cooperative Oncology Group (ECOG) performance status (PS) 1 were 38 (66.7%) and PS 2 – 19 (33.3%). Sarcopenia was present in 29 (50.8%) patients, of which 16 (55.2%) men and 13 (44.8%) women. Presence of sarcopenia was related only to patients PS (p = 0.003) and gross tumor volume (GTV) (p = 0.002). A significantly negative correlation was detected between TMT and GTV (rho = -0.263; p = 0.048). Patients with PS 2 had significantly lower TMT and higher GTV than patients with PS 1. There was not significant difference in TMT between gender. Patients with sarcopenia had a significantly shorter mean progression – free survival (PFS) than patients without sarcopenia (6.01 months, 95% CI: 4.15-7.19 vs 13.57 months, 95% CI: 10.21-16.92; p < 0.001). Patients with sarcopenia had a significantly shorter mean overall survival (OS) than patients without sarcopenia (10.01 months, 95% CI: 7.96-12.06 vs 28.39 months, 95% CI: 21.14-35.64; p < 0.001). Moreover, when controlling for age, sex and PS presence of sarcopenia was independent poor prognostic marker in multiple Cox regression model (HR=7.11, 95% CI 2.62-19.27; p < 0.001). Conclusions: Low TMT is an independent predictor for poor outcome in patients with GBM treated with concurrent chemoradiotherapy.