Olivia Newton-John Cancer Research Institute, Heidelberg, Victoria, Australia; School of Cancer Medicine, Latrobe University, Melbourne, Victoria, Australia.
Department of Medical Imaging, St Vincent's Hospital, Fitzroy, Victoria, Australia.
Int J Radiat Oncol Biol Phys. 2018 Nov 15;102(4):783-791. doi: 10.1016/j.ijrobp.2018.03.013. Epub 2018 Mar 21.
Accurate tumor delineation is a priority in radiation therapy (RT). Metabolic imaging has a key and evolving role in target volume selection and delineation. This is especially so for non-small cell lung cancer, squamous cell cancer of the head and neck, and lymphoma, for which positron emission tomography/computed tomography (PET/CT) is complimentary to structural imaging modalities, not only in delineating primary tumors, but also often in revealing previously undiagnosed regional nodal disease. At some sites, PET/CT has been confirmed to enable target size reduction compared with structural imaging alone, with enhanced normal tissue sparing and potentially allowing for dose escalation. These contributions often dramatically affect RT strategies. However, some limitations exist to the use of fluorodeoxyglucose-PET in RT planning, including its relatively poor spatial resolution and partial voluming effects for small tumors. A role is developing for contributions from metabolic imaging to RT planning at other tumor sites and exciting new applications for the use of non-fluorodeoxyglucose metabolic markers for RT planning.
准确的肿瘤勾画是放射治疗（RT）的重点。代谢成像在靶区选择和勾画中具有关键且不断发展的作用。对于非小细胞肺癌、头颈部鳞状细胞癌和淋巴瘤尤其如此，正电子发射断层扫描/计算机断层扫描（PET/CT）不仅在勾画原发肿瘤方面，而且在揭示以前未诊断的区域淋巴结疾病方面，与结构成像方式相辅相成。在某些部位，与单独使用结构成像相比，PET/CT 已被证实可以缩小靶区大小，同时更好地保护正常组织，并可能允许提高剂量。这些贡献常常显著影响 RT 策略。然而，在 RT 计划中使用氟脱氧葡萄糖-PET 存在一些局限性，包括其相对较差的空间分辨率和小肿瘤的部分容积效应。代谢成像在其他肿瘤部位的 RT 计划中的作用正在发展，并且对于使用非氟脱氧葡萄糖代谢标志物进行 RT 计划的新应用也令人兴奋。
