Segmenting lung tumors on longitudinal imaging studies via a patient-specific adaptive convolutional neural network Journal Article


Authors: Wang, C.; Tyagi, N.; Rimner, A.; Hu, Y. C.; Veeraraghavan, H.; Li, G.; Hunt, M.; Mageras, G.; Zhang, P.
Article Title: Segmenting lung tumors on longitudinal imaging studies via a patient-specific adaptive convolutional neural network
Abstract: Purpose: To design a deep learning algorithm that automatically delineates lung tumors seen on weekly magnetic resonance imaging (MRI) scans acquired during radiotherapy and facilitates the analysis of geometric tumor changes. Methods: This longitudinal imaging study comprised 9 lung cancer patients who had 6–7 weekly T2-weighted MRI scans during radiotherapy. Tumors on all scans were manually contoured as the ground truth. Meanwhile, a patient-specific adaptive convolutional neural network (A-net) was developed to simulate the workflow of adaptive radiotherapy and to utilize past weekly MRI and tumor contours to segment tumors on the current weekly MRI. To augment the training data, each voxel inside the volume of interest was expanded to a 3 × 3 cm patch as the input, whereas the classification of the corresponding patch, background or tumor, was the output. Training was updated weekly to incorporate the latest MRI scan. For comparison, a population-based neural network was implemented, trained, and validated on the leave-one-out scheme. Both algorithms were evaluated by their precision, DICE coefficient, and root mean square surface distance between the manual and computerized segmentations. Results: Training of A-net converged well within 2 h of computations on a computer cluster. A-net segmented the weekly MR with a precision, DICE, and root mean square surface distance of 0.81 ± 0.10, 0.82 ± 0.10, and 2.4 ± 1.4 mm, and outperformed the population-based algorithm with 0.63 ± 0.21, 0.64 ± 0.19, and 4.1 ± 3.0 mm, respectively. Conclusion: A-net can be feasibly integrated into the clinical workflow of a longitudinal imaging study and become a valuable tool to facilitate decision- making in adaptive radiotherapy. © 2018 Elsevier B.V.
Keywords: clinical article; controlled study; treatment duration; cancer patient; cancer radiotherapy; nuclear magnetic resonance imaging; diagnostic accuracy; tumor volume; tumor regression; simulation; lung tumor; statistical analysis; geometry; external beam radiotherapy; mri; longitudinal study; artificial neural network; non small cell lung cancer; image segmentation; voxel based morphometry; diagnostic test accuracy study; learning algorithm; workflow; human; priority journal; article; deep learning; adaptive convolutional neural network; root mean square surface distance
Journal Title: Radiotherapy and Oncology
Volume: 131
ISSN: 0167-8140
Publisher: Elsevier Inc.  
Date Published: 2019-02-01
Start Page: 101
End Page: 107
Language: English
DOI: 10.1016/j.radonc.2018.10.037
PROVIDER: scopus
PMCID: PMC6615045
PUBMED: 30773175
DOI/URL:
Notes: Export Date: 1 February 2019 -- Source: Scopus
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MSK Authors
  1. Andreas Rimner
    524 Rimner
  2. Pengpeng Zhang
    175 Zhang
  3. Gikas S Mageras
    277 Mageras
  4. Guang Li
    98 Li
  5. Margie A Hunt
    287 Hunt
  6. Yu-Chi Hu
    118 Hu
  7. Neelam Tyagi
    151 Tyagi
  8. Chuang Wang
    9 Wang