From the Department of Radiology, University of Texas Health at San Antonio, 7703 Floyd Curl Dr, San Antonio, TX 78229 (L.K., A.M.P., V.S.K.); Department of Radiology, University of Texas MD Anderson Cancer Center, Houston, Tex (S.R.P., S.Y., L.P.M.); Department of Radiology, Mayo Clinic, Scottsdale, Ariz (K.S., C.O.M.); and Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio (S.H.T.).
Radiographics. 2021 May-Jun;41(3):876-894. doi: 10.1148/rg.2021200171. Epub 2021 Apr 23.
A wide spectrum of second cancers occur as late complications of radiation therapy (RT) used to treat various malignancies. In addition to the type and dose of radiation, lifestyle, environmental, and genetic factors are important to the development of second malignancies in cancer survivors. Typically, RT-induced malignancies (RTIMs) are biologically aggressive cancers with a variable period of 5-10 years for hematologic malignancies and 10-60 years for solid tumors between RT and the development of the second cancer. Although carcinomas and leukemias commonly develop after low-dose RT, sarcomas occur in tissues or organs that receive high-dose RT. Angiosarcomas and unclassified pleomorphic sarcomas are the two most common RT-associated sarcomas; other sarcomas include malignant peripheral nerve sheath tumors, leiomyosarcomas, osteosarcomas, chondrosarcomas, and dedifferentiated or pleomorphic liposarcomas. Select RTIMs show tumor genetic characteristics that allow accurate diagnosis. Nearly all cutaneous angiosarcomas after RT for breast cancer and 90% of RT-associated malignant peripheral nerve sheath tumors are characterized by gene amplifications and loss of H3 K27me3 expression respectively. Classic papillary thyroid carcinomas that develop after RT frequently harbor rearrangements and have a favorable prognosis, despite their advanced stage at patient presentation. Select RTIMs demonstrate characteristic imaging findings and typically develop in the prior radiation field. Imaging is essential to early diagnosis, characterization, localization, and staging of RTIMs. Familiarity of radiologists with the diverse spectrum of RTIMs is essential for early diagnosis and optimal management. RSNA, 2021.
各种恶性肿瘤的放射治疗（RT）会导致广泛的第二癌症作为晚期并发症。除了辐射的类型和剂量外，生活方式、环境和遗传因素对于癌症幸存者第二癌症的发生也很重要。通常，RT 诱导的恶性肿瘤（RTIMs）是具有生物学侵袭性的癌症，血液系统恶性肿瘤在 RT 后 5-10 年、实体肿瘤在 RT 后 10-60 年之间发展为第二癌症。尽管低剂量 RT 后常发生癌和白血病，但肉瘤发生在接受高剂量 RT 的组织或器官中。血管肉瘤和未分类的多形性肉瘤是两种最常见的与 RT 相关的肉瘤；其他肉瘤包括恶性外周神经鞘肿瘤、平滑肌肉瘤、骨肉瘤、软骨肉瘤和去分化或多形性脂肪肉瘤。一些 RTIMs 具有肿瘤遗传特征，允许进行准确诊断。几乎所有乳腺癌 RT 后的皮肤血管肉瘤和 90%的 RT 相关恶性外周神经鞘肿瘤分别具有 基因扩增和 H3 K27me3 表达缺失的特征。RT 后发生的经典乳头状甲状腺癌经常发生 重排，尽管患者就诊时已处于晚期，但预后良好。一些 RTIMs 具有特征性的影像学表现，且通常发生在之前的放射治疗区域。影像学对于 RTIMs 的早期诊断、特征描述、定位和分期至关重要。放射科医生对各种 RTIMs 的广泛认识对于早期诊断和最佳管理至关重要。RSNA，2021 年。
