Ewing Sarcoma as Secondary Malignant Neoplasm—Epidemiological and Clinical Analysis of an International Trial Registry

Abstract

Ewing sarcoma (EwS) is the second most common bone and soft tissue tumor, affecting primarily adolescents and young adults. Patients with secondary EwS are excluded from risk stratification in several studies and therefore do not benefit from new therapies. More knowledge about patients with EwS as secondary malignant neoplasms (SMN) is needed to identify at-risk patients and adapt follow-up strategies. Epidemiology, clinical characteristics, and survival analyses of EwS as SMN were analyzed in 3844 patients treated in the last three consecutive international EwS trials, EICESS 92, Euro-E.W.I.N.G. 99, and EWING 2008. Forty-two cases of EwS as SMN (approximately 1.1% of all patients) were reported, preceded by a heterogeneous group of malignancies, mainly acute lymphoblastic leukemias (n = 7) and lymphomas (n = 7). Three cases of EwS as SMN occurred in the presumed radiation field of the primary tumor. The median age at diagnosis of EwS as SMN was 19.4 years (range, 5.9–72) compared with 10.8 years (range, 0.9–51.2) for primary EwS. The median interval between first malignancy and EwS diagnosis was 7.4 years. The 3-year overall survival (OS)/event-free survival (EFS) was 0.69 (SE = 0.09)/0.53 (SE = 0.10) for localized patients and 0.36 (SE = 0.13)/0.29 (SE = 0.12) for metastatic patients (OS: p = 0.02; EFS: p = 0.03). Survival in patients with EwS as SMN did not differ between hematologic or solid primary malignancies. EwS as SMN is rare; however, survival is similar to that of primary EwS, and its risk-adjusted treatment should be curative, especially in localized patients.

Osteosarcoma Arising After Ewing Sarcoma orVice Versa: A Report of 20 Affected Patients from the Cooperative Osteosarcoma Study Group (COSS)

“…To date, the low frequency of affected patients with both malignancies has limited analyses of epidemiological variables, apart from radiotherapy administered against the first cancer, and prognostic factors associated with better chances of survival of the second. The Cooperative Ewing Sarcoma Study Group CESS, like our group run under the auspices of the German Society of Pediatric Oncology and Hematology (GPOH), has very recently presented their experiences with both secondary malignancies arising after Ewing sarcomas (3) and secondary Ewing sarcomas (10), respectively. While there is considerable patient overlap between their group and ours, the clear focus on osteosarcomas, a detailed analysis of received therapies, and a presentation of long-term outcomes still make our analysis unique.…”