Outcome of multimodality treatment of Ewing's sarcoma of the extremities

The management of Ewing's sarcoma family of tumors (ESFT, Ewing's sarcoma/primitive neuroectodermal tumor) has been established as a multimodality treatment. Advances in imaging and diagnostics, chemotherapy, surgical techniques, radiotherapy and prosthetic technology have resulted in drastic changes in the outcome of this disease, with most of the recent studies having 5-year survival rates of more than 60%. The Indian patients present at a more advanced stage and the compliance of treatment is suboptimal. While there is plenty of data in the world literature on the outcome of Ewing's sarcoma, there is paucity of data in Indian patients. Therefore, we conducted the present study to analyze the outcome of multimodality treatment of ESFT of the extremities at a tertiary nonprofit institute over a decade.

34 patients who had histopathologically proven diagnosis of Ewing's sarcoma of the extremities and had received treatment at our institute from 1997 through 2007 were included for analysis. The majority of patients had involvement of the femur (35%), followed by tibia (17%), fibula and foot (15% each), humerus (12%) and soft tissue of thigh (6%). Twenty-nine patients presented with localized disease (Enneking stage II B) while five patients presented with metastases (Enneking stage III). All patients received Vincristine, Actinomycin D, Cyclofosfamide + Ifosfamide and Etoposide (VAC+IE)-based chemotherapy and local treatment was offered to all but three patients having multicentric disease. The local treatment offered were, radiation (n= 15), surgery (n= 12) both surgery and radiation (n=4). All patients were analyzed for oncological outcome (event-free and overall survival, local and systemic relapses) by clinical and imaging evaluation and functional outcome by using the musculoskeletal tumor society (MSTS) score. These outcomes were correlated with age, sex, size of tumor, stage at presentation, modality of local treatment and site of relapse.

At the final follow-up (mean, 26 months; median, 17 months; range, 3-97 months), the overall and event-free survivals were 47 ± 12% and 34 ± 9%, respectively. Sixty-two percent of the patients presented with a tumor size more than 8 cm. On correlation with age, sex, size of tumor, stage at presentation, modality of local treatment and site of relapse, no correlation of survival was seen with any of the variables except event-free survival with size of the tumor. The functional outcome of all the patients was satisfactory (MSTS score >16 out of 30). No patient underwent amputation.

Although the demographic profile, stage at presentation and the local and systemic treatment regimen followed in our study was similar to the world literature, the outcome of Ewing's sarcoma in Indian patients were found to be inferior to that reported in the western literature. Larger multicentric studies with longer follow-up are required to exactly determine the key areas crucial in improving this outcome.