PML expression in soft tissue sarcoma: Prognostic and predictive value in alkylating agents/antracycline-based first line therapy.

INTRODUCTION: Soft tissue sarcomas are aggressive tumours representing less than 1% of all adult neoplasms. Aim of our study was to evaluate PML value as prognostic factor and as a factor predicting response to alkylating agents/antracycline-based first line therapy. MATERIALS AND METHODS: 111 patients affected by locally advanced and metastatic soft tissue sarcoma were selected. PML expression was evaluated by immunohistochemical analysis in pathological samples and in the corresponding normal tissue from each case. PML immunohistochemical results were correlated with prognosis and with radiological response to alkylating agents/antracycline-based first line therapy. RESULTS: PML expression was significantly reduced in synovial sarcomas (P <0.0001), in myofibroblastic sarcomas (P <0.0001), angiosarcomas (P <0.0001), leiomyosarcomas (P =0.003), mixoid liposarcomas (P <0.0001) and in dedifferentiated liposarcomas (P <0.0001). No significant difference was found for pleomorphic sarcoma (31.8 [95% CI: 16.7 - 41.0; P =0.21). and pleomorphic liposarcomas (P =0.51). Loss of PML expression was found to be statistically correlated with TTP (P <0.0001), median duration of response (P =0.007) and OS (P =0.02). No correlation was observed between PML expression and treatment efficacy. CONCLUSIONS: PML IHC expression is downregulated in synovial sarcomas, myofibroblastic sarcomas, angiosarcomas, liposarcoma and leiomyosarcomas and its expression correlated with prognosis.