Feasibility of Tomotherapy-Based Image-Guided Radiotherapy for Small Cell Lung Cancer

Nam P. Nguyen, Wei Shen, Sarah Kratz, Jacqueline Vock, Paul Vos, Vinh-Hung Vincent, Gabor Altdorfer, Lars Ewell, Siyoung Jang, Ulf Karlsson, Juan Godinez, Melissa Mills, Thomas Sroka, Suresh Dutta, Alexander Chi, The International Geriatric Radiotherapy Group

Background: To assess the tolerance of patients with small cell lung cancer undergoing chemoradiation with tomotherapy-based image-guided radiotherapy (IGRT). Materials and Methods: A retrospective review of the toxicity profile for nine patients with small cell lung cancer of the limited stage who underwent chemoradiation delivered with helical tomotherapy (HT) has been conducted. Results: Acute grade 3-4 hematologic and esophagitis toxicities developed in two and three patients respectively. One patient developed a pulmonary embolism during radiotherapy. Seven patients had weight loss ranging from 0 to 30 pounds (median: 4 pounds). Three patients had treatment breaks ranging from 2 to 12 days. At a median follow-up of 11 months (range: 2-24 months), no patients developed any radiation related toxicities such as grade 3-4 pneumonitis or other long-term complications. The median survival was estimated to be 15 months. There were two local recurrences, three mediastinal recurrences, and six distant metastases. Conclusion: Grade 3-4 toxicities remained significant during chemoradiation when radiation was delivered with tomotherapy-based IGRT. However, the absence of grade 3-4 pneumonitis is promising and the use of HT needs to be investigated in future prospective studies.