HISTOLOGIC GRADING IN SOFT-TISSUE SARCOMAS - AN ANALYSIS OF 194 CASESINCLUDING AGNOR COUNT AND MAST-CELL COUNT

In order to establish a new histologic grading system for STS, we eval uated histologic prognostic factors. For this purpose, we selected 194 patients with STS: 31 in the upper extremities, 63 in the trunk, and 100 in lower extremities. All the patients were treated by surgery, fo llowed by chemotherapy in 74 cases, radiotherapy in 11, chemotherapy a nd radiotherapy in 30, or no adjuvant treatment in 79. Histologic fact ors evaluated were mitotic count, extent of necrosis, cellularity, cel lular pleomorphism, extent of myxoid change, sclerosis, non-specific h istologic diagnosis, counting of reaction product in silver stain for nucleolar organizer regions (AgNOR) and mast-cell counts. Univariate a nalysis revealed mitotic count, necrosis, cellularity, cellular pleomo rphism, non-specific histologic classification, AgNOR count and mast-c ell count to be significantly related to prognosis. Multivariate analy sis revealed that AgNOR count, cellularity and necrosis were independe nt prognostic factors. A new grading system was introduced: low-grade, intermediate-grade and high-grade. The survival between each group we re significantly different; the 5-year-survival rate in patients of th e low-, intermediate- and high-grade groups was 87%, 74% and 35% respe ctively. Our findings suggest that this histologic grading system may be useful for making therapeutic decisions.