骨肉瘤患者可能会出现尤文肉瘤，反之亦然。我们的目的是更多地了解哪些患者会发生这些继发性肿瘤、哪些治疗可能有效以及哪些患者可能存活。在骨肉瘤合作研究组 (1980-09/2022) 的数据库中搜索了所有患有骨肉瘤的患者 (包括未分化的多形性骨肉瘤），并且在之前或之后的任何时间也患有尤文肉瘤（包括周围神经外胚层肿瘤）。然后对所确定的患者进行患者、肿瘤和治疗相关变量以及最后一次随访时的疾病和生存状态分析。总共 20 名符合条件的患者 [17 名先于骨肉瘤患尤文肉瘤，3 名反之亦然;男10名，女10名；确定第一次癌症时的中位年龄为 10.5 (2.4-20.6)，第二次癌症时的中位年龄为 20.5 (9.9-42.4) 岁]。没有患者患上第三种癌症，也没有患者患有已知的肿瘤易感综合征。十六/17继发性骨肉瘤和没有继发性尤文肉瘤在先前接受过辐射的部位发生。十九/20 (95%) 患者接受了针对其第一种和第二种癌症的主要多药化疗。继发性癌症诊断后五年的精算总生存率和无事件生存率分别为 69% 和 42%。 尤文肉瘤后出现的继发性骨肉瘤几乎完全与放射有关。事实并非如此，反之亦然。不管怎样，通过适当的多学科治疗，长期生存是现实的可能。因此，治疗疏忽显然是不够的。版权所有 © 2023，国际抗癌研究所（George J. Delinasios 博士），保留所有权利。

Ewing sarcoma can arise in patients after osteosarcoma or vice versa. Our aim was to learn more about which patients develop these secondary tumors, which treatments may be effective, and which patients might survive.The database of the Cooperative Osteosarcoma Study Group (1980-09/2022) was searched for all patients with an osteosarcoma (including undifferentiated pleomorphic sarcoma of the bone) who also suffered from Ewing sarcoma (incl. peripheral neuroectodermal tumor) at any time, previously or thereafter. The identified patients were then analyzed for patient, tumor, and treatment-related variables as well as their disease- and survival-status at the last follow-up.A total of 20 eligible patients [17 Ewing sarcoma prior to osteosarcoma, 3 vice versa; 10 males, 10 females; median age at 1st cancer 10.5 (2.4-20.6), at 2nd cancer 20.5 (9.9-42.4) years] were identified. None of the patients developed a 3rd cancer and none had a known tumor-predisposition syndrome. Sixteen/17 secondary osteosarcomas and no secondary Ewing sarcoma developed in sites that had previously been irradiated. Nineteen/20 (95%) patients received primary multi-agent chemotherapy for their 1st and 2nd cancers. Actuarial overall and event-free survival probabilities at five years after the diagnosis of the secondary cancer were 69% and 42%, respectively.Secondary osteosarcoma arising after Ewing sarcoma is almost exclusively associated with radiation. This is not the case vice versa. Either way, long-term survival is a realistic possibility with appropriate multidisciplinary treatment; thus, therapeutic negligence is clearly inadequate.Copyright © 2023, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.