ICHNO-ECHNO 2022 - Abstract Book

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ICHNO-ECHNO 2022

Conclusion Despite the omission of immediate neck dissections in 95% of those who achieved an EQR nodal response, there was no difference in late survival between the EQR and CR groups. This validates the safety of extended surveillance in HPV- positive patients who achieve an EQR.

Proffered papers: New data from randomised trials

OC-0012 Hypofractionated vs standard radiotherapy in elderly unfit patients with HN cancer: ELAN-RT trial

C. ORTHOLAN 1 , A. Aupérin 2 , X. Sun 3 , Y. Tao 4 , S. Renard-Oldrini 5 , C. Lafond 6 , B. Guillaume 7 , P. Boisselier 8 , K. Bénézéry 9 , S. Racadot 10 , F. Huguet 11 , M. Bollet 12 , A. Braccini 13 , C. Khoury 14 , J. Stéphane 15 , J. Villa 16 , L. Martin 17 , D. Belemsagha 18 , W. Nadia 19 , A. Goineau 20 , N. Cheurfa 2 , C. Mertens 21 , H. Le Caer 22 , J. Bourhis 23 , J. Bourrhis 24 , J. Guigay 25,26 1 Centre Hospitalier Princesse Grace, Radiation oncology, Monaco, Monaco; 2 Institut Gustave Roussy, Biostatistics, Villejuif, France; 3 Hôpital Nord Franche-Comté, Radiation Oncology, Montbéliard, France; 4 Institut Gustave Roussy, Radiation Oncology, Villejuif, France; 5 Institut de Cancérologie de Lorraine, Radiation Oncology, Vandœuvre-lès-Nancy, France; 6 Clinique Victor Hugo, Radiation Oncology, Le Mans, France; 7 Groupe Hospitalier Bretagne Sud, Radiation Oncology, Lorient, France; 8 Institut du Cancer Montpellier, Radiation Oncology, Montpellier, France; 9 Centre Antoine Lacassagne, Radiation Oncology, Nice, France; 10 Centre Léon Bérard, Radiation Oncology, Lyon, France; 11 Hôpital Tenon, Radiation Oncology, Paris, France; 12 Institut Hartmann, Radiation Oncology, Levallois-Perret, France; 13 Centre Azuréen de Cancérologie, Radiation Oncology, Mougins, France; 14 Centre de Radiothérapie Saint-Louis Croix Rouge Française, Radiation Oncology, Toulon, France; 15 Centre de Cancérologie du Grand Montpellier, Radiation Oncology, Montpellier, France; 16 CHU Grenoble Alpes, Radiation Oncology, Grenoble, France; 17 Centre Guillaume le Conquérant, Radiation Oncology, Le Havre, France; 18 Hôpital Forcilles Fondation, Radiation Oncology, Forcilles, France; 19 Institut de Cancérologie de l' Ouest, Radiation Oncology, Nantes, France; 20 Institut de Cancérologie de l'Ouest, Radiation Oncology, Angers, France; 21 Institut Bergognié, Geriatric Oncology, Bordeaux, France; 22 Centre hospitalier de la Dracênie, Oncology, Draguignan, France; 23 Centre Hospitalier Universitaire Vaudois, Radiation Oncology, Lausanne, Switzerland; 24 GORTEC (Groupe d'Oncologie Radiothérapie Tête Et Cou), Radiation Oncology, Tours, France; 25 Centre Antoine Lacassagne, Oncology, Nice, France; 26 GORTEC (Groupe d'Oncologie Radiothérapie Tête Et Cou), Oncology, Tours, France Purpose or Objective Standard treatment for elderly patients (pts) with localized head neck squamous cell carcinoma (HNSCC) not suitable for surgery is standard fractionated radiotherapy (SF-RT) 70 Gy/35 fractions (fct). In routine practice, high toxicity and multiple fractions of SFR-RT lead physicians to often deliver adapted hypofractionated split course radiotherapy (HSC-RT) for frail pts. The ELAN (ELderly heAd and Neck cancer) RT trial is the first phase III comparing SF-RT to HSC-RT in elderly unfit pts (NCT01864850). Materials and Methods Pts with stage II-IV HNCSCC aged ≥ 70 were first enrolled in ELAN-ONCOVAL study classifying pts in fit/unfit using a geriatric evaluation. Unfit pts in curative situation were eligible to the multicentric non-inferiority ELAN-RT trial, comparing SF-RT (70Gy, 35 fct over 7 weeks) and HSC-RT (55 Gy in 20 fct over 6 weeks: 10 fct/2 weeks-2 weeks stop-10 fct/2 weeks). Primary endpoint was rate of pts alive without residual locoregional disease at 6 months, with a non-inferiority margin of 16%. Efficacy analyses were performed in intention-to-treat (ITT) and per protocol (PP). Results 201 pts were randomized from 10/2013 to 09/2018: 100 in the SF-RT arm and 101 in the HSC-RT arm. 28% were male. Mean age was 81.6 years (range 71-97), 64% pts were ≥ 80 years, 76% pts were PS 0-1, 24% PS 2, 92% pts had G8 score ≤ 14. 44% of tumors were in oropharynx (49% p16+), 22% in larynx, 17% in hypopharynx and 16% in oral cavity. Stage II, III and IV were 27%, 33% and 40% in SF-RT arm and 28%, 26% and 47% in HSC-arm. Three pts in each arm did not receive RT. 85 pts completed the 35 fct in the SF-RT arm and 87 pts completed 20 fct in the HSC-RT arm. Among pts who received all expected fcts, the overall treatment time was increased of > 7 days in 31% of pts in the SF-RT arm and 16% in the HSC-RT arm. Grade 3-4 acute toxicities were 45% in the SF-RT arm and 34% in the HSC-RT arm (p=0.12). Acute skin toxicity grade 2 or over was 31% in SF-RT arm and 13% in the HSC-RT arm (p=0.003). In ITT analysis, HSC-RT was non-inferior to SF-RT for the primary endpoint with 35 patients (34%; 95%CI 24%-44%) alive without residual locoregional disease at 6 months in the SF-RT arm versus 34 (35%; 95%CI 25%-45%) in the HSC-RT arm (rejection of inferiority hypothesis p=0.01). Median progression-free survival was 7.9 months (95%CI 5.2-11.1) in the HSC- RT arm versus 11.1 months (95%CI 8.1-17.5) in the SF-RT arm with HR=1.30 (95%CI 0.93-1.82). The median overall survival (OS) was 12.8 months (95%CI 9.8-17.0) in the HSC-RT arm versus 19.3 months (95%CI 14.3-29.9) in the SF-RT arm with HR=1.42 (IC95% 1.00-2.02). Results were similar in PP analysis. Conclusion Conclusion: Considering the primary endpoint, HSC-RT is not inferior to SF-RT. HSC-RT could be an option for unfit patients, but, due to the observed survival results, it should be offered only to patients not suitable for SF-RT. Careful geriatric assessment and proper patients selection is mandatory.