Recurrence of head and neck squamous cell carcinoma in relation to high-risk treatment volume. (March 2021)

• Record Type: Journal Article
• Authors: Nissi, Linda; Suilamo, Sami; Kytö, Eero; Vaittinen, Samuli; Irjala, Heikki; Minn, Heikki
• Is Part Of: Clinical and translational radiation oncology. Volume 27(2021)
• Page Start: 139
• Page End: 146
• Publication Date: 2021-03
• Subjects: CRT chemoradiotherapy -- CT computed tomography -- DFS disease-free survival -- 18F-fluorodeoxyglucose FDG -- HNSCC head and neck squamous cell carcinoma -- HPV human papilloma virus -- IMRT intensity modulated radiotherapy -- MRI magnetic resonance imaging -- OS overall survival -- PET positron emission tomography -- RT radiation therapy; Head and neck cancer -- Human papillomavirus -- Tumor recurrence -- Radioresistance -- In-field recurrence; Cancer -- Radiotherapy -- Periodicals; Oncology -- Periodicals; Cancer -- Radiotherapy; Oncology; Radiation Oncology; Neoplasms -- radiotherapy; Translational Medical Research; Periodicals; Electronic journals; Periodicals; 616.9940642
• DOI: 10.1016/j.ctro.2021.01.013
• Languages: English
• ISSNs: 2405-6308

Abstract

Highlights: Distribution of recurrent HNSCC in relation to radiotherapy volume was evaluated. Both p16 positive and negative HNSCC recur in high-risk treatment volume. This indicates potential failure of multimodality imaging to disclose significant disease. A need for biomarkers other than p16 to predict radiosensitivity continues to exist. Abstract: Background: Locoregional recurrence remains a major cause of failure in head and neck squamous cell carcinoma (HNSCC). Human papilloma virus (HPV)-associated HNSCCs generally have a good prognosis but may recur even after standard photon radiotherapy (RT). Another incentive in observing patterns of recurrence is increased use of highly conformal techniques such as proton therapy. We therefore studied geographic distribution of recurrent tumors in relation to the high-risk treatment volume in a cohort of patients with HNSCC receiving combined modality therapy. Methods: Medical records of 508 patients diagnosed with HNSCC in 2010–2015 were reviewed. We identified a subgroup that had local and/or regional recurrence at hybrid positron emission tomography (PET)/computed tomography (CT) and/or magnetic resonance imaging (MRI). We adapted p16 as a surrogate marker for HPV-positivity and only patients with known p16 status were eligible for a detailed analysis where recurrent tumor was copied on the planning CT and the dose received by the recurrent tumor volume was determined using dose-volume histograms. Results: Twenty-five patients who had received either cisplatin (n = 23) or cetuximab-enhanced (n = 2) RT were identified. 31 locoregional recurrent tumors were detected among 18 p16 negative and 7 p16 positive patients. Of recurrent tumors 14 (45%) were classified as in-field, 5 (16%) as marginal miss, and 12 (39%) as true miss. p16 positive patients had 4 in-field, 2 marginal, and 1 true miss. By contrast, p16 negative patients had 10 in-field, 3 marginal, and 11 true miss recurrences. Conclusions: Both p16 positive and negative HNSCC recur in high-risk treatment volume despite the common view of high radiosensitivity of the former. Biomarkers predicting radioresistance should be characterized in p16 positive tumors before widely embarking on de-escalated CRT protocols. Another concern is how to decrease the number of true or marginal misses in p16 negative cases despite multimodality imaging-based target delineation.