Prognostic factors of primary resected retroperitoneal soft tissue sarcoma: Analysis from a single asian tertiary center and external validation of gronchi's nomogram.

ABSTRACT

BACKGROUND: Surgery is the potentially curative treatment for retroperitoneal sarcoma (RS), but complete resectability is frequently a challenge. This study aimed to characterize the clinical features, prognostic factors and treatment outcomes. METHODS: A cohort of 144 patients with RS was surveyed retrospectively from January 1st, 2000 to July 30th, 2011. The prognostic influence of clinicopathological characteristics as well as treatments on local recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), and overall survival (OS), were examined by univariate and multivariate analyses. A histology-specific nomogram developed by Gronchi et al was used for validation. RESULTS: Liposarcoma, leiomyosarcoma, and malignant peripheral sheath tumor (MPNST) were the most common histologies (70%). Multivariate analysis revealed FNCLCC tumor grade was the most significant prognostic factor for OS (P = 0.001) and DMFS (P < 0.001) and complete resection was the only significant prognostic factor for LRFS (P = 0.043). Incomplete resection of grade 3 tumor was significantly associated with a worse OS. Despite some differences in characteristics between our patients and Gronchi's cohort, external validation of Gronchi's nomogram demonstrated excellent concordance in predicting survival. CONCLUSIONS: Our study demonstrated tumor grade and surgical margins had significant prognostic influence and the Gronchi's nomogram has an excellent applicability in predicting survival of STS patients. J. Surg. Oncol. 2016;113355-360. © 2016 Wiley Periodicals, Inc.