Importance of tumor size in soft tissue sarcomas: a proposal for a nomogram based on a score system to staging soft tissue sarcomas in the postoperative setting

In order to adequately stage patients with extremity soft tissue sarcomas (ESTS), it is mandatory to include all adverse prognostic factors and create an integral staging system. We were able to evaluate a nomogram based on a score (STSSS), to improve ESTS staging. We retrospectively evaluated 596 patients with ESTS in stages I-III, of the American Joint Committee on Cancer (AJCC), who had a complete resection. We analyzed the influence of clinicopathological factors on metastasis, recurrence, and disease-specific survival. The STSSS was based on histologic grade (HG), profundity, tumor size (TS), and surgical margins; we also compared STSSS versus AJCC systems in their ability to stage ESTS. The mean TS was 11.8 cm, with 50 % >10 cm. Large TS and high HG were independent but adverse prognostic factors for metastasis. In addition, large TS, high grade, and R1 resection were independent adverse prognostic factors for decreased survival. There was a progressive decline in survival as TS increased, although AJCC staging did not correlate well between stages (IA vs. IB p = 0.233, IA vs. IIA p = 0.123, IA vs. IIB p = 0.075, IB vs. IIA p = 0.472, IB vs. IIB p = 0.211). STSSS showed differences between these categories for 5-year survival (I vs. II p = 0.003, II vs. III p = 0.002, III vs. IV p < 0.001). Surgical margins, HG, and TS are important determinants for metastases and survival. We also found a strong correlation between survival and prognosis with the use of STSSS in the immediate postoperative setting.