Мала товщина скроневого м’яза - незалежний несприятливий прогностичний чинник у пацієнтів із метастазами в головний мозок, які отримують радіохірургічне лікування

Objective: The aim of this Bulgarian study was to determine the impact of temporal muscle thickness (TMT), a prognostic factor for sarcopenia, in patients with brain metastases (BMs) treated with radiosurgery. Methods: A retrospective analysis was conducted using TMT values from planning brain magnetic resonance imaging (MRI) studies for 232 patients diagnosed with brain metastases originating from various histological solid tumors. These measurements were taken prior to their initial radiosurgery procedure, conducted between January 2021 and December 2022. The total TMT for both the left and right sides was calculated by summing them and then dividing by two to determine the average TMT. The cut-off value was determined for TMT based on the median of the measured values among all participants. Additionally, sarcopenia was assessed as an independent prognostic factor through Cox regression models that accounted for other relevant prognostic variables. Results: In sarcopenia patients with a TMT below the cut-off values, specifically the median TMT (5.42 mm), the risk of death was significantly increased (HR = 6.310, 95% CI: 4.161–9.568, p < 0.001). In addition, sarcopenia was revealed to be an independent prognostic factor even after adjusting for gender, number of BMs, cancer type, and ECOG Performance Status (HR = 5.757, 95% CI: 3.717–8.915, p < 0.001). Patients with sarcopenia had a significantly shorter mean OS (5.46 months, 95% CI = 5.00–5.91) compared to those without sarcopenia (23.40 months, 95% CI = 20.62–26.18) (log-rank test P < 0.001). Conclusions: In patients with BMs treated with radiosurgery, TMT from planning MRI studies serves as an independent prognostic marker and may help with patient stratification in future clinical trials.