Bhatnagar Sharad, Sharma Shweta, Semwal Manoj, Singh Sankalp
Department of Radiation Oncology, Army Hospital Research & Referral, New Delhi, India.
Department of Radiation Oncology, Narayana Superficiality Hospitals, Kolkata, West Bengal, India.
J Med Phys. 2019 Oct-Dec;44(4):276-282. doi: 10.4103/jmp.JMP_13_19. Epub 2019 Dec 11.
Does metabolic imaging help in better definition of target during radiation treatment planning by bringing about changes in dimensions of the primary tumor in terms of diameter, length, and picking up new skip lesions or nodal stations which in turn prevents geographic misses by including more F-fluorodeoxyglucose avid regions not visible on conventional imaging?
We compared the length and radial dimensions of the primary tumor as well as changes brought about due to addition of new nodal stations, involved structures, and skip lesions in 50 patients of carcinoma esophagus treated between 2011 and 2013, as seen on contrast-enhanced computed tomography (CT) thorax and positron emission tomography (PET)/CT and drew conclusions regarding the technical changes brought about in treatment planning by the additional input of PET/CT.
PET-CT tremendously changes treatment plans by expanding the gross tumor volume and including regions which might otherwise have been missed on purely CT-based plans. Of the 50 patients, it changed the contouring and treatment planning of 35 patients and did not impact the remaining 15. Whether this translates into better long-term controls requires further validation by randomized controlled trials, which was not our present objective.
代谢成像能否通过改变原发性肿瘤在直径、长度方面的尺寸，以及发现新的跳跃性病变或淋巴结站，从而在放射治疗计划中更精确地定义靶区，进而通过纳入更多传统成像上不可见的氟脱氧葡萄糖摄取区域来避免靶区遗漏？
我们比较了2011年至2013年间接受治疗的50例食管癌患者的原发性肿瘤的长度和径向尺寸，以及因增加新的淋巴结站、受累结构和跳跃性病变而产生的变化，这些变化在胸部增强计算机断层扫描（CT）和正电子发射断层扫描（PET）/CT上可见，并就PET/CT的额外输入给治疗计划带来的技术变化得出结论。
PET-CT通过扩大大体肿瘤体积并纳入单纯基于CT的计划中可能遗漏的区域，极大地改变了治疗计划。在这50例患者中，它改变了35例患者的轮廓勾画和治疗计划，而对其余15例没有影响。这是否能转化为更好的长期控制效果，需要通过随机对照试验进一步验证，而这并非我们目前的目标。
