Residual tumor after unplanned excision reflects clinical aggressiveness for soft tissue sarcomas

The aims of this study are to investigate clinical and pathological factors associated with the existence of residual tumor in reexcised specimens (RTRS) following unplanned excisions for soft tissue sarcomas and to determine whether RTRS has an impact on the oncologic outcome. A total of 113 patients with soft tissue sarcoma who received unplanned excision at the prereferral hospital were treated with additional reexcision at our institutions from 1986 to 2010. Clinical and pathological variables were analyzed as possible factors correlated with the existence of RTRS. These factors in addition to surgical margin in reexcisions were analyzed as factors possibly correlated with the oncological outcome. RTRS was observed in 58 cases (51 %). Histological subtype tended to associate with the presence of RTRS (P = 0.063), particularly in patients with dermatofibrosarcoma protuberances (DFSP) (83 %) and myxofibrosarcoma (100 %), whereas the other factors did not. Five-year local recurrence-free, metastasis-free, and overall survival (LRFS, MFS, and OS) were 93, 96, and 97 %, respectively. Patients with RTRS tended to have lower LRFS (89 %) than those without (97 %, P = 0.067) and had significantly lower MFS (92 %) than those without (100 %, P = 0.043). Other factors had no impact on prognosis. Patients receiving unplanned excision particularly for myxofibrosarcoma and DFSP require reexcision with an adequate surgical margin. Although patients with unplanned excision have a favorable clinical outcome following additional wide reexcision, those with RTRS require careful follow-up.