Outcomes for Soft-Tissue Sarcoma in 8249 Cases from a Large State Cancer Registry

Background and objectives

To date, outcome reports for soft-tissue sarcoma (STS) have largely been limited to single or paired institutional series. To more accurately elucidate population-based outcomes and prognostic factors associated with STS, a large cancer registry was examined.

Methods

STS arising in the Florida Cancer Data System were examined (1981–2004).

Results

A total of 8249 patients were identified, the calculated annual incidence of sarcoma being approximately 38 cases per million in 2003. The tumor histologies among these patients were leiomyosarcoma and gastrointestinal stromal tumor (LMS/GIST) (43.5%), malignant fibrous histiocytoma (MFH) (31.5%), liposarcoma (19.0%), and fibrosarcoma (6.0%). Tumors were situated in the extremities (30.7%), truncal or visceral locations (50.4%), retroperitoneum (11.7%), and head or neck (7.2%). Thirty-three percent of lesions were over 10 cm in greatest dimension, while 50.2% were classified as high grade. Median overall survival was 25 months. Superior survival was observed for liposarcomas and fibrosarcomas as compared to MFH and LMS/GIST (P < 0.001). Retroperitoneal and truncal sarcomas had a more ominous prognosis than did other sites (P < 0.001). Multivariate analysis of pretreatment variables demonstrated that increasing age, male gender, non-Caucasian race, advanced stage, and a truncal or retroperitoneal location were each independently associated with lower survival. Histological subtype was also an independent predictor of outcome. Surgical resection and radiation therapy were the only treatment variables shown to improve survival.

Conclusions

Histological subtype, tumor site, and stage are independent prognostic factors in STS. Surgical resection and radiotherapy are unique among treatment modalities in association with a significant survival benefit.

Introduction

Soft-tissue sarcomas (STS) are uncommon, biologically and histologically heterogeneous neoplasms arising from mesenchymal tissues throughout the body [1]. Approximately 9420 cases were diagnosed in the United States in 2005, accounting for less than 1% of all new malignancies [2, 3, 4]. Traditionally, the mainstay of treatment for STS has been surgical resection with tumor-free margins, adjuvant or neoadjuvant chemotherapy, and/or radiation coming into their own with the advent of limb-, tissue-, and function-sparing surgery [5, 6, 7]. Tumor size, grade, stage, and surgical margin status are identified in single-institution series as the most important prognostic factors in these tumors [8, 9, 10, 11]. To date, treatment strategy has been determined more by anatomical site than by histological subtype [12]. Only recently have investigators focused significantly on the influence of histology on prognosis [13, 14].

The sarcoma literature is dominated by retrospective series from single institutions or pooled data from two or more institutions with major tertiary referral practices. Such series are limited by small sample size and selection bias in favor of advanced, recurrent, or otherwise complicated sarcomas. These factors may skew survival and other treatment outcomes in this uncommon, heterogeneous group of tumors. We therefore analyzed a large, population-based cancer registry to better identify prognostic factors for survival.