Early prediction of tumour-response to radiotherapy in NSCLC patients
Authors
Amugongo, Lameck MVasquez Osorio, Eliana
Green, Andrew
Cobben, D.
van Herk, Marcel
McWilliam, Alan
Affiliation
Division of Cancer Sciences, University of Manchester, Manchester,Issue Date
2021
Metadata
Show full item recordAbstract
Objective. In this study we developed an automatic method to predict tumour volume and shape in weeks 3 and 4 of radiotherapy (RT), using cone-beam computed tomography (CBCT) scans acquired up to week 2, allowing identification of large tumour changes.Approach. 240 non-small cell lung cancer (NSCLC) patients, treated with 55 Gy in 20 fractions, were collected. CBCTs were rigidly registered to the planning CT. Intensity values were extracted in each voxel of the planning target volume across all CBCT images from days 1, 2, 3, 7 and 14. For each patient and in each voxel, four regression models were fitted to voxel intensity; applying linear, Gaussian, quadratic and cubic methods. These models predicted the intensity value for each voxel in weeks 3 and 4, and the tumour volume found by thresholding. Each model was evaluated by computing the root mean square error in pixel value and structural similarity index metric (SSIM) for all patients. Finally, the sensitivity and specificity to predict a 30% change in volume were calculated for each model.Main results. The linear, Gaussian, quadratic and cubic models achieved a comparable similarity score, the average SSIM for all patients was 0.94, 0.94, 0.90, 0.83 in week 3, respectively. At week 3, a sensitivity of 84%, 53%, 90% and 88%, and specificity of 99%, 100%, 91% and 42% were observed for the linear, Gaussian, quadratic and cubic models respectively. Overall, the linear model performed best at predicting those patients that will benefit from RT adaptation. The linear model identified 21% and 23% of patients in our cohort with more than 30% tumour volume reduction to benefit from treatment adaptation in weeks 3 and 4 respectively.Significance. We have shown that it is feasible to predict the shape and volume of NSCLC tumours from routine CBCTs and effectively identify patients who will respond to treatment early.Citation
Amugongo LM, Osorio EV, Green A, Cobben D, van Herk M, McWilliam A. Early prediction of tumour-response to radiotherapy in NSCLC patients [Internet]. Vol. 66, Physics in Medicine & Biology. IOP Publishing; 2021. p. 225002.Journal
Physics in Medicine and BiologyDOI
10.1088/1361-6560/ac2f88PubMed ID
34644691Additional Links
https://dx.doi.org/10.1088/1361-6560/ac2f88Type
ArticleLanguage
enae974a485f413a2113503eed53cd6c53
10.1088/1361-6560/ac2f88