NY-ESO-1 antigen expression as a prognostic factor for soft tissue sarcomas.

Abstract

11075 Background: While a number of antigens are known to be expressed in soft tissue sarcomas, little is known about the prognosis of patients with such tumors. Recent data have demonstrated immunologic activity in sarcoma patients expressing the NY-ESO antigen, found positive in 20-80% cases. MAGE A3 has also recently attracted attention with regard to soft tissue sarcomas. In our study we aimed to assess any association between antigen expression and prognosis. Methods: In a case-control study we retrospectively collected data from a prospective database of all 137 patients with sarcomas receiving first line therapy in the Petrov Research Institute of Oncology in Saint-Petersburg. All cases were morphologically verified, with mRNA expression of NY-ESO-1, MAGE A3, PDGFR A, PDGFR B, beta-tubullin and top2alpha additionally being tested by quantitative real-time PCR in a subset of patients. The log-rank test was applied to compare Kaplan-Mayer estimates of progression-free (PFS) and overall survival (OS) by univariate analysis. Hazard ratios were derived after adjustment for age, gender, several covariates for type of chemotherapy and disease stage with two-sided probability at a significance level of 0.05. Results: The positive rate for expression of NY-ESO was 20% (11/43).Only NY-ESO was significantly associated with PFS (p < 0,001), with a median durations of 10, 4 and 7 months for positive, negative and not tested for NY-ESO expression, respectively. The adjusted hazard ratio (HR) for NY-ESO positive patients was 2.2 (95%CI, 1.2;4.2) compared with their negative counterparts, The HR for patients not tested for NY-ESO was 2.0 (95%CI, 1.3;3.0). Among other covariates, only a combination of drugs was associated with a lower risk of progression (HR, 0.7 95%CI, 0.4;0.98) , as compared to those receiving a single chemotherapy agent. Conclusions: This first report showing prognostic significance of NY-ESO expression in soft tissue sarcoma patients, suggests that research should be focused on targeting this antigen. Participation in clinical trials for patients with positive NY-ESO expression is highly recommended, because of poor survival regardless of the type of standard treatment.