Distal lower extremity sarcomas: frequency of occurrence and patient survival rate.

BACKGROUND: Primary sarcomas in the distal leg, tibia, fibula, ankle, and foot are uncommon and are believed to be less malignant than those that arise in other sites, but only limited information is available to support this contention.
METHODS: Using a computerized system containing extensive information regarding over 14,000 patients, mostly with tumors treated by our center over a 25-year period, 175 sarcomatous lesions with MSTS stage I, II, and III were located in the distal lower extremity. These were compared with 2367 lesions of similar diagnoses in other body parts. The principal studies included diagnostic distribution and outcome (recorded as death as a result of disease). Data were compared for diagnosis, gender, age, Musculoskeletal Tumor Society (MSTS) stage, anatomic site, and treatment methods and evaluated statistically by chi-square methods.
RESULTS: The most frequent distal lower limb tumors were synovial cell sarcoma, osteosarcoma, and Ewing's tumor and the percentage distribution of the various tumors for that site as compared with the rest of the body was quite different. Of even more importance was the remarkable difference in outcome with the death rate for the lower limb tumors set at 10%, while the same tumors at other sites had a death rate of 27% (p <.000002). Furthermore, gender, stage, age, and the type of operative procedure showed highly significant differences between the tumors of the lower leg and those of the remainder of the body.
CONCLUSIONS: On the basis of these data, it is evident that far fewer sarcomas occur in the lower leg, tibia, fibula, ankle, and foot than in other body sites and that their diagnostic distribution is different. Of perhaps greater interest is the fact that the rate of metastasis and death is markedly reduced for this site as compared with others. The authors speculate on the causes of this remarkable alteration in numbers and outcome.