Session Item

The purpose of the study is to analyze the response rate (RR) and the side effects of the combined treatment including hyperthermia, radiotherapy and chemotherapy for patients with soft tissue sarcomas (STS).

We retrospectively reviewed patients affected by STS treated at our institution with hyperthermia combined with radiotherapy and/or chemotherapy. Two radiative hyperthermia (HT) devices were used: BSD-500 system for superficial HT and BSD-2000 system for deep regional HT for target sited >4 cm from the skin. Duration of each HT session was of 60 minutes with target temperature >40°. The dose for neoadjuvant or adjuvant treatments was 45-50 Gy and 60-66 in case of radical intent, with conventional fractionation. Chemotherapy consisted of gemcitabine 300 mg/mq administered weekly during radiotherapy or HD-ifosfamide i.c. The RR was evaluated by CT scan and MRI scan. The assessment of adverse events was reported according to NCI CTCAE v4.0.

From November 2019 to May 2021 twenty-one patients (8 males and 13 females, median age 65.5 years) with STS were treated with the combination. Eighteen patients had localized disease and 3 had metastastic disease. The most frequent sites of treatment were the lower limb and the abdominal-pelvic region. The mean target size was 7.9 cm (range 1-20 cm). Thirteen patients were treated with hyperthermia and radiotherapy alone, seven with concomitant radiochemotherapy (ifosfamide or gemcitabine) and one with chemotherapy alone. The intent of treatment was neoadjuvant in 13 patients (61.9%), adjuvant in 2 (9.5%), radical in 3 patients (14.2%) and palliative in 3 cases (14.2%). Fifteen patients (71.4%) were treated with superficial HT and 6 (28.6%) with deep HT. Overall radiological RR was 52.3% (11/21 pts). Twelve patients underwent surgery after neoadjuvant therapy. In all cases R0 resection was obtained and in 5 cases a complete pathological response was reported. The integrated treatment of radiotherapy and chemotherapy in association with HT was well tolerated: no hyperthermia session was interrupted due to side effects. No skin toxicity > grade 2 was detected and only one patient had haematological toxicity ≥ grade 3.

In our experience the addition of HT in the therapeutic protocol of patients with STS did not increase the toxicity of the treatment, showing promising results. The trimodal combination of HT, radiotherapy and chemotherapy, should be investigated on a larger number of patients in order to confirm its feasibility and efficacy.