A staging system for soft-tissue sarcoma and its evaluation in relation to treatment.

ABSTRACT

In order to define the significant factors for a staging system of soft-tissue sarcomas (STS), histologic and clinical findings in 190 adult patients with localized STS in the extremities and trunk were reviewed. The male-to-female ratio was 1.21. The histologic grading of tumors was defined according to the criteria recently proposed by us tumors were low-grade in 65 cases, intermediate-grade in 57 cases and high-grade in 68 cases. The initial surgical procedure was as follows intracapsular excision in 9 cases, marginal excision in 104 and wide local excision in 77, including 15 amputations. The mode of treatment was surgery alone (101 patients), surgery and chemotherapy (58), surgery and radiotherapy (22) and surgery and combined chemo- and radiotherapy (9). Univariate analysis revealed histologic grade, sex, tumor size and tumor depth to be significant prognostic factors. Multivariate analysis revealed histologic grade to be the only independent factor for prognosis. Significant clinical factors in each histologic grade were then evaluated. In the low-grade group, local recurrence significantly affected prognosis. Most of the patients with local recurrence had had marginal resection as the initial surgical procedure. No clinical factors affecting prognosis in the intermediate-grade group could be determined. In the high-grade group, patients with wide local excision and adjuvant chemotherapy had a better prognosis than those with marginal excision with or without adjuvant chemotherapy and wide local excision without chemotherapy (p = 0.09). In conclusion, histologic grade was the only significant factor for the staging of STS. On the basis of our staging system, different modalities of treatment for each grade of STS might be indicated; adequate surgery is essential for the prevention of local recurrence, which resulted in reduced mortality in patients with low-grade STS. For high-grade STS, the prevention of distant metastasis by combined extensive surgery and adjuvant chemotherapy may make long-term survival possible.