Histologic grading of adult soft tissue sarcomas.

Histologic grading is currently the most important prognostic factor for adult soft-tissue sarcomas. The French grading system is based on a score generated by evaluating three parameters: tumor differentiation, mitotic rate and amount of tumor necrosis. This system has been compared to the National Cancer Institute System. Histologic grade particularly indicates the probability of distant metastasis and overall survival, but not the probability of local recurrence. In our experience, it is an independent prognostic factor for the whole group of adult soft-tissue sarcomas, but also for malignant fibrous histiocytomas, liposarcomas, leiomyosarcomas, synovial sarcomas and unclassified sarcomas. It is also a useful tool for deciding which patients should receive chemotherapy.