Effect of concurrent chemotherapy and hyperthermia on outcome of preoperative radiotherapy of high-risk soft tissue sarcomas

As treatment results for high-risk soft tissue sarcoma are still disappointing, treatment intensification is warranted. We performed a retrospective analysis of multimodal preoperative treatment to evaluate the additional effect of concurrent chemotherapy and/or locoregional hyperthermia in comparison to radiotherapy alone. Between 1999 and 2011, 28 patients were treated with neoadjuvant radiotherapy to a median 45 Gy for high-risk soft tissue sarcoma. All tumors were deep-seated and grade 2 or 3, 86% (n = 24) larger than 5 cm. Multimodal treatment (n = 12) consisted of ifosfamide (n = 7), locoregional hyperthermia (n = 3), or both modalities (n = 2) concurrent to radiotherapy. Prognostic factors (grade, size, histology, location) were balanced in the groups with and without concurrent multimodal treatment. There was a significant improvement of disease-specific survival (100% vs. 70% at 3 years, p = 0.03) with multimodal treatment. Distant metastases-free survival was influenced, but was not statistically significant. Local control and disease-free survival did not differ in the two groups. Our data suggest that multimodal treatment with ifosfamide and/or locoregional hyperthermia in combination with neoadjuvant radiotherapy might improve outcome in high-risk soft tissue sarcomas.