Recommendations for postoperative radiotherapy in head & neck squamous cell carcinoma in the presence of flaps: A GORTEC internationally-reviewed HNCIG-endorsed consensus

Florent Carsuzaa , Michel Lapeyre , Vincent Gregoire , Philippe Maingon , Arnaud Beddok , Pierre-Yves Marcy , Julia Salleron , Alexandre Coutte (1) , Severine Racadot , Yoann Pointreau , Pierre Graff , Beth Beadle , Karen Benezery , Julian Biau , Valentin Calugaru , Joel Castelli , Melvin Chua , Alessia Di Rito , Melanie Dore , Pirus Ghadjar , Florence Huguet , Pauline Jardel , Jorgen Johansen , Randall Kimple , Marco Krengli , Sarbani Laskar , Lachlan Mcdowell , Anthony Nichols , Silke Tribius , Izaskun Valduvieco , Chaosu Hu , Xavier Liem , Antoine Moya-Plana (2, 3) , Ida d'Onofrio , Upendra Parvathaneni , Vinita Takiar , Ester Orlandi , Amanda Psyrri , George Shenouda , David Sher , Conor Steuer , Xu Shan Sun , Yungan Tao (3) , David Thomson , Mu-Hung Tsai , Noemie Vulquin , Philippe Gorphe (3) , Hisham Mehanna , Sue S. Yom , Jean Bourhis , Juliette Thariat

1 CHIMERE - CHirurgie, IMagerie et REgénération tissulaire de l’extrémité céphalique - Caractérisation morphologique et fonctionnelle - UR UPJV 7516
2 Département de radiothérapie [Gustave Roussy]
3 CCF - Département de cancérologie cervico-faciale [Gustave Roussy]

Introduction: Head and neck reconstructive surgery using a flap is increasingly common. Best practices and outcomes for postoperative radiotherapy (poRT) with flaps have not been specified. We aimed to provide consensus recommendations to assist clinical decision-making highlighting areas of uncertainty in the presence of flaps. Material and methods: Radiation, medical, and surgical oncologists were assembled from GORTEC and internationally with the Head and Neck Cancer International Group (HNCIG). The consensus-building approach covered 59 topics across four domains: (1) identification of postoperative tissue changes on imaging for flap delineation, (2) understanding of tumor relapse risks and target volume definitions, (3) functional radiation-induced deterioration, (4) feasibility of flap avoidance. Results: Across the 4 domains, international consensus (median score > 7/9) was achieved only for functional deterioration (73.3%); other consensus rates were 55.6% for poRT avoidance of flap structures, 41.2% for flap definition and 11.1% for tumor spread patterns. Radiation-induced flap fibrosis or atrophy and their functional impact was well recognized while flap necrosis was not, suggesting dose-volume adaptation for the former. Flap avoidance was recommended to minimize bone flap osteoradionecrosis but not soft-tissue toxicity. The need for identification (CT planning, fiducials, accurate operative report) and targeting of the junction area at risk between native tissues and flap was well recognized. Experts variably considered flaps as prone to tumor dissemination or not. Discrepancies in rating of 11 items among international reviewing participants are shown. Conclusion: International GORTEC and HNCIG-endorsed recommendations were generated for the management of flaps in head and neck radiotherapy. Considerable knowledge gaps hinder further consensus, in particular with respect to tumor spread patterns. (c) 2021 Elsevier B.V. All rights reserved. Radiotherapy and Oncology 160 (2021) 140-147 Results: Across the 4 domains, international consensus (median score > 7/9) was achieved only for functional deterioration (73.3%); other consensus rates were 55.6% for poRT avoidance of flap structures, 41.2% for flap definition and 11.1% for tumor spread patterns. Radiation-induced flap fibrosis or atrophy and their functional impact was well recognized while flap necrosis was not, suggesting dose-volume adaptation for the former. Flap avoidance was recommended to minimize bone flap osteoradionecrosis but not soft-tissue toxicity. The need for identification (CT planning, fiducials, accurate operative report) and targeting of the junction area at risk between native tissues and flap was well recognized. Experts variably considered flaps as prone to tumor dissemination or not. Discrepancies in rating of 11 items among international reviewing participants are shown. Conclusion: International GORTEC and HNCIG-endorsed recommendations were generated for the management of flaps in head and neck radiotherapy. Considerable knowledge gaps hinder further consensus,

Domaines: Sciences du Vivant [q-bio]

Florent Carsuzaa, Michel Lapeyre, Vincent Gregoire, Philippe Maingon, Arnaud Beddok, et al.. Recommendations for postoperative radiotherapy in head & neck squamous cell carcinoma in the presence of flaps: A GORTEC internationally-reviewed HNCIG-endorsed consensus. Radiotherapy & Oncology, 2021, 160, pp.140-147. ⟨10.1016/j.radonc.2021.04.026⟩. ⟨hal-03600466⟩