Selection bias in treatment of soft-tissue sarcoma.

We analysed 256 patients with primary soft-tissue sarcoma of the extremities diagnosed between 1970 and 1990 to see if tumour-related and host-related prognostic factors influenced both the selection of operation and the margin of clearance obtained at surgery. Amputation was more often performed in young patients, in those with distal tumours, and in those with deep-seated tumours. Inadequate surgical margins (those with a high risk of local recurrence) were more common in patients with deep-seated and large tumours than in patients with superficial and small tumours. These features of the tumour and the host, which have been shown to be prognostic for survival, also influenced the choice and performance of surgical procedures.