Regional deep hyperthermia in combination with whole brain radiotherapy (WBRT) in poor prognosis patients with brain metastases

Purpose: The aim of this study is to assess for the first time, the role of regional deep hyperthermia in combination with radiotherapy and systemic therapy in patients with poor prognosis of brain metastases (GPI ≤ 2.5).

Methods: Patients with confirmed cerebral metastases and classified as GPI score ≤ 2.5 were included in this prospective study. Pretreatment stratification was defined as patients with 0-1 GPI score (Group A) and patients with 1.5-2.5 GPI score (Group B). HT was applied twice a week, 60 min per session, during RT by regional capacitive device (HY-DEEP 600WM system) at 13.56 MHz radiofrequency.

Results: Between June 2015 and June 2017, 15 patients and a total of 49 brain metastases were included in the protocol. All patients received all HT sessions as planned. RT and systemic therapy were also completed as prescribed. Tolerance to treatment was excellent and no toxicity was registered. Patients with HT effective treatment time longer than the median (W90time > 88%) showed better actuarial PFS at 6 and 12 months (100% and 66.7%, respectively) compared to those with less HT effective treatment time (50% and 0%, respectively) (p < 0.031). Median OS was 6 months (range 1-36 months). Stratification by GPI score showed a median OS of 3 months (CI 95% 2.49-3.51) in Group A and 8.0 months (CI 95% 5.15-10.41) in Group B (p = 0.035).

Conclusions: Regional hyperthermia is a feasible and safe technique to be used in combination with RT in brain metastases patients, improving PFS and survival in poor prognostic brain metastasis patients.

Keywords: Brain metastases; Hyperthermia; Radiotherapy.