Whole Lung Irradiation in Patients With Relapsed Ewing Sarcoma

Abstract

There is no standard treatment procedure for relapsed Ewing sarcoma (ES). This retrospective analysis evaluates the outcome and pulmonary function in patients with isolated pulmonary or additional extrapulmonary relapse of ES treated with whole lung irradiation (WLI). 55 patients (median age 21 years, range 7-52 years) with relapsed ES and isolated pulmonary (29) or additional extrapulmonary (26) lesions were analysed (median follow-up 3years, range 7m-11y9m). The multimodal treatment regime included WLI for 30 patients with a dose between 15-18Gy by the complete pulmonary remission after polychemotherapy (CT) or high-dose chemotherapy (HDCT). 2-years local control (2-y. LC) and 3-years overall survival (3-y. OS) were statistically examined. A significant benefit for WLI vs. no WLI was seen for patients with isolated pulmonary relapse – 2-y. LC 71% vs 24%, p=0.02; 3-y. OS 65% vs 24%, p=0.03. No benefit for WLI for 2-y. LC and 3-y. OS was observed in patient’s group with additional extrapulmonary lesions. Combined treatment modalities including WLI demonstrated superior outcome in comparison to treatment modes without WLI. So, a superior values for 2-y. LC and 3-y. OS were received for the multimodal treatment including CT or HDCT, resection of residual pulmonary lesion and completed with WLI (71%, p=0.03 and 68%, p=0.04 correspondingly). The poorest values were observed after HDCT alone with busulfan/melphalan (2-y. LC 12%, 3-y. OS 0%). A progress of the pulmonary lesions during the treatment was observed only by the treatment modalities without WLI. 1 from 30 irradiated patients developed an acute pulmonary toxicity with moderate functional impairment. In total, 37% of patients without radiotherapy of primary ES tumor developed pulmonary lesions in the relapsed ES independently of primary tumor site. These data indicate a benefit for WLI in patients with ES relapse and isolated pulmonary lesions. An acceptable pulmonary and cardiac toxicity was observed after WLI. As long as there is no randomized prospective analysis, the present data confirm the indication for WLI in relapsed Ewing tumor with isolated lung manifestations. For patients with additional extrapulmonary relapse the WLI can be discussed by the complete remission of all manifested lesions.