Patterns of locoregional failure following post-operative intensity-modulated radiotherapy to oral cavity cancer: quantitative spatial and dosimetric analysis using a deformable image registration workflow

Year: 2017

Type: article

Abstract: BACKGROUND: We sought to identify spatial/dosimetric patterns of failure for oral cavity cancer patients receiving post-operative IMRT (PO-IMRT). METHODS: Two hundred eighty-nine OCC patients receiving PO-IMRT were retrospectively reviewed from 2000 to 2012. Diagnostic CT documenting recurrence (rCT) was co-registered with planning CT (pCT) using a validated deformable image registration software. Manually segmented recurrent gross disease (rGTV) was deformed to co-registered pCTs. Mapped rGTVs were compared dosimetrically to planned dose and spatially to planning target volumes using centroid-based approaches. Failures types were classified using combined spatial/dosimetric criteria: A (central high-dose), B (peripheral high-dose), C (central intermediate/low-dose), D (peripheral intermediate/low-dose), and E (extraneous-dose). RESULTS: (IQR 1.4-10.6). For spatial and dosimetric analysis of the patterns of failure, 30 patients (55.5%) were classified as type A (central high-dose). Non-central high dose failures were distributed as follows: 2 (3.7%) type B, 10 (18.5%) type C, 1 (1.8%) type D, and 9 (16.7%) type E. Non-IMRT failure in the matching low-neck field was seen in two patients. No failures were noted at the IMRT-supraclavicular field match-line. CONCLUSIONS: Approximately half of patients with local/regional failure had non-central high dose recurrence. Peripheral high dose misses were uncommon reflecting adequate delineation and dose delivery. Future strategies are needed to reduce types C and E failures.

Source: Radiation Oncology

DOI: 10.1186/s13014-017-0868-y

Authors: Abdallah S. R. Mohamed, Andrew J. Wong, Clifton D. Fuller, Mona Kamal, Gary B. Gunn, Jack Phan, William H. Morrison, Beth M. Beadle, Heath Skinner, Stephen Y. Lai, Sean R. Quinlan-Davidson, Abdelaziz M. Belal, Ahmed G. El-Gowily, Steven J. Frank, David I. Rosenthal, Adam S. Garden

Institutions: The University of Texas MD Anderson Cancer Center, Alexandria University, Ain Shams University

Language: English

Topic: Advanced Radiotherapy Techniques

Subfield: Radiation

Field: Physics and Astronomy

Domain: Physical Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $3,290

Funders: National Science Foundation, Elekta, National Institutes of Health, University of Texas MD Anderson Cancer Center, National Cancer Institute, National Institute of Dental and Craniofacial Research, Division of Mathematical Sciences

OpenAlex ID: W2745496366