Tumours in Iceland. 14. Malignant tumours of soft tissues. Histological classification and epidemiological considerations

Expression of multidrug-resistance-associated protein gene in human soft-tissue sarcomas

We examined the mRNA expression of the multidrug- resistance-associated protein gene (MRP) in soft-tissue sarcomas and compared it with the expression of the multidrug resistance gene (MDR1), using the reverse transcriptase/polymerase chain reaction. We investigate 39 samples from 33 cases of soft-tissue sarcomas (11 liposarcomas, 9 malignant fibrous histiocytomas, 6 leiomyosarcomas, 4 malignant schwannomas, 3 fibrosarcomas, 3 synovial sarcomas, and 3 epithelioid sarcomas) and 7 benign soft-tissue tumors. All samples were obtained prior to chemotherapy. An expression of MRP mRNA was noted in 56% of soft-tissue sarcoma specimens. The co-expression of MRP and MDR1 was recognized in 15 samples (38%) (5/11 liposarcomas, 5/9 malignant fibrous histiocytomas, 3/6 leiomyosarcomas, 2/3 fibrosarcomas) and significantly correlated with histological grade (P=0.0165). A positive and significant correlation was found between MRP and MDR1 expression in soft-tissue sarcomas(P=0.0013). In benign soft-tissue tumors, 1 chemodectoma and 1 neurothekeoma showed low MRP expression; however, no case showed co-expression of MRP and MDR1.

Sarcomas in north west England: III. Survival

Survival data on a population-based series of bone, soft tissue and visceral sarcomas diagnosed in the North West of England between 1982-84 and subjected to histopathological peer review are presented. Five-year crude survival for all cases was 34%. Survival in males and females did not differ significantly (P = 0.6, 5-year survival 32% vs 36%) but was markedly worse for patients diagnosed over the median age of 60 years, even when allowance was made for underlying mortality (P = 0.03, 34% vs 44%). Five-year survival rates for the major site groups were: bone 44%; soft tissues of head, neck and trunk 36%; soft tissues of extremities 35%; female genital tract 35%; retroperitoneum 15%; gastro-intestinal tract 13%. Analysis by the major histological types revealed the following survival rates: leiomyosarcoma--female genital tract 25%, gastro-intestinal tract 14%, non-visceral soft tissue 21%; malignant fibrous histiocytoma of soft tissue 29%; liposarcoma 52%; osteosarcoma of bone 46%; and chondrosarcoma of bone 50%.