MR-imaging changes of musculoskeletal soft-tissue sarcomas associated with neoadjuvant chemotherapy and hyperthermia

Purpose: To evaluate early changes in musculoskeletal soft-tissue sarcomas under neoadjuvant chemotherapy combined with regional hyperthermia (RHT). Patients and methods: Nineteen consecutive patients with high-grade soft-tissue sarcomas of the musculoskeletal system were treated with neoadjuvant chemotherapy combined with RHT. Patients were imaged, using a high field MR-scanner, before onset of therapy, immediately after one and after four cycles of therapy. The images were evaluated for volume reduction and development of tumour necrosis. In addition, side effects such as surrounding soft-tissue oedema, bleeding and muscle or bone marrow necrosis were analysed. Results: Tumour volume reduction was significant after the completion of neoadjuvant therapy (mean 49%, range 5-91%; ( p < 0.001). Extent of tumour necrosis was also significantly different before (mean 22%) and after therapy (mean 58%, p < 0.001). Three patients showed strong tumour necrosis already after one cycle of treatment. Tumour volume reduction was not associated with the extent of pre-existing necrosis or necrosis development. The extent of tumour volume before start of therapy did not affect volume reduction or necrosis induction after therapy. Reduction of tumour oedema was significant after therapy ( p < 0.001). No side effects were observed during thermochemotherapy. Conclusion: Neoadjuvant chemotherapy combined with RHT resulted in significant tumour volume reduction and induction of tumour necrosis, which can be detected early and monitored closely with MRI.