Treatment of pelvic Ewing's sarcoma: Pros and cons of chemotherapy plus definitive radiotherapy versus surgery.

Objective: The aim of this study was to compare the results of chemotherapy or combined chemotherapy-radiation therapy with surgical intervention following neodjuvant therapy in pelvic Ewing's sarcoma patients.

Methods: The study population consisted of 39 patients with pelvic Ewing's sarcoma treated in our clinic between 1994 and 2014. Of these patients, 28 patients (11 boys and 17 girls; mean age: 19.57±6.8 years) were treated with chemotherapy and radiation therapy and the remaining 11 patients (9 boys and 2 girls; mean age: 18.64±8.1 years) patients underwent surgical intervention after neoadjuvant chemotherapy or chemotherapy plus radiation therapy. Internal hemipelvectomy was performed in 10 patients, and external hemipelvectomy was performed in one patient. Survival rates were compared between the surgical and non-surgical treatment groups. Predictive factors, such as treatment protocol (surgery, neoadjuvant chemotherapy, definitive radiotherapy), mass localisation, mass size, presence of metastasis at the time of diagnosis, and presence of late metastases were compared between the groups. The effects of each variable on survival were also examined.

Results: The overall 3- and 5-year survival rates of the 28 non-surgical patients were 41.4% and 26.1%, respectively, while those of the surgical patients were 53% and 35.4%, respectively (p=0.777). Large mass size, presence of metastasis at the time of diagnosis, and presence of late metastases were significantly associated with lower survival rates.

Conclusion: The survival rates of the patients who underwent surgery were higher than those of non-surgical patients, although the difference was not statistically significant. Definitive radiation and chemotherapy would be preferable in selected cases, such as patients with sacral localisation, without surgical intervention.

Level Of Evidence: Level III, Therapeutic Study.