A Synovial Sarcoma-Specific Preoperative Nomogram Supports a Survival Benefit to Ifosfamide-Based Chemotherapy and Improves Risk Stratification for Patients

Abstract

To identify prognostic factors related to outcome in 255 patients with synovial sarcoma and to construct a preoperative nomogram to predict the risk of disease-specific death. Between July 1982 and June 2006, 301 patients underwent treatment at our institution for primary synovial sarcoma of all anatomic sites and 255 patients with localized disease at presentation were resected with curative intent. Data were collected prospectively and analyzed retrospectively. Five-, 10-, and 15-year disease-specific survival (DSS) was 72%, 60%, and 53%, respectively. Multivariate analysis revealed size and primary tumor site as the only independent adverse predictors of disease-specific death. A nomogram based on preoperative data for surgical patients not receiving anthracycline-ifosfamide (AI) chemotherapy (n = 196) estimates 3- and 5-year DSS with a concordance index of 77.3%. For the first 3 years following diagnosis, the observed DSS for patients treated with AI chemotherapy (n = 59) was greater than that predicted by the preoperative nomogram based on patients not receiving AI chemotherapy. SYT-SSX fusion transcript data were available for 132 patients. Multivariate analysis of this subset showed that SYT-SSX1 fusion type was predictive of early, but not late, distant recurrence. Size and location govern prognosis in primary synovial sarcoma resected with curative intent. A nomogram based on preoperative variables provides individualized patient survival estimates and shows an early survival benefit to chemotherapy that may dissipate over time. This nomogram may improve decision-making with regards to selecting patients most likely to benefit from neoadjuvant/adjuvant chemotherapy.