Long-Term Survival According to Histology and Radiologic Response to Preoperative Chemotherapy in 126 Patients Undergoing Resection of Non-GIST Sarcoma Liver Metastases.

Background: Non-gastrointestinal stromal tumor sarcomas (NGSs) have heterogeneous histology, and this heterogeneity may lead to uncertainty regarding the prognosis of patients with liver metastases from NGS (NGSLM) and decision regarding their surgical management. Furthermore, the role of preoperative chemotherapy in treatment of NGSLM remains poorly defined. We investigated long-term survival and its correlation to response to preoperative chemotherapy in patients with NGSLM.
Patients and Method: Patients who underwent liver resection for NGSLM during 1998-2015 were identified. Clinical, histopathologic, and survival data were analyzed. Multivariate analysis was performed using a Cox proportional hazards model.
Results: 126 patients [62 (49%) with leiomyosarcoma] were included. Five-year overall survival (OS) and recurrence-free survival (RFS) rates were 49.3 and 14.9%, respectively. Survival did not differ by histologic subtype, primary tumor location, or use of preoperative or postoperative chemotherapy. NGSLM ≥ 10 cm and extrahepatic metastases at NGSLM diagnosis were the only independent risk factors for OS. In the 83 (66%) patients with metachronous NSGLM, disease-free interval > 6 months was associated with improved OS and RFS. Among the 65 patients (52%) who received preoperative chemotherapy, radiologic response according to Choi criteria specifically was associated with improved OS (p = 0.04), but radiologic response according to RECIST 1.1 criteria was not.
Conclusions: Resection of NGSLM led to a 5-year OS rate of 49%, independent of histologic subtype and primary tumor location. Choi criteria (which take into account tumor density) are superior to RECIST 1.1 in assessing radiologic response and should be used to assess response to preoperative chemotherapy.