ESTRO 2024 - Abstract Book

S1332

Clinical - Head & neck

ESTRO 2024

1739

Proffered Paper

Local control patterns of GORTEC 2014-04 IIR Trial of SABR or chemo-SABR in oligometastastic HNSCCs

juliette thariat 1 , mathieu bosset 2 , antoine falcoz 3 , dewi vernerey 3 , yoann pointreau 4 , severine racadot 5 , jean christophe faivre 6 , joel castelli 7 , sebastien guihard 8 , florence huguet 9 , sophie chapet 10 , yungan tao 11 , pauline maury 11 , yann sayous 11 , jean bourhis 12 , xu shan sun 13 1 centre baclesse, radiation oncology, caen, France. 2 clinique marie curie, radiation oncology, valence, France. 3 , University Hospital of CHBM, Methodological and Quality of Life in Oncology Unit, Besançon, France. 4 Institut Inter Regional de Cancerologie-Centre Jean Bernard, Radiation Oncology, le mans, France. 5 centre leon berard, radiation oncology, lyon, France. 6 Institut de cancérologie de Lorraine centre Alexis-Vautrin, radiation oncology, vandoeuvre les nancy, France. 7 centre eugene marquis, radiation oncology, rennes, France. 8 Centre Paul-Strauss, Institut de cancérologie Strasbourg Europe, radiation oncology, strasbourg, France. 9 Hôpital Tenon, AP-HP, Sorbonne Université, radiation oncology, paris, France. 10 Centre Henry-Kaplan, université François-Rabelais, CHRU, radiation oncology, tours, France. 11 Gustave Roussy Cancer Campus, radiation oncology, villejuif, France. 12 chuv, radiation oncology, lausanne, Switzerland. 13 Hôpital Nord Franche-Comté, Montbéliard and CHRU, radiation oncology, montbeliard, France

Purpose/Objective:

Stereotactic Ablative Radiotherapy (SABR) is increasingly used in genuine oligometastases (oMets) to defer initiation of systemic treatments or switch to later lines. In induced oMets, SABR serves as a consolidative treatment of residual or oligoprogressive disease on the ground with little scientific assessment of such practice & its impact on outcomes of drug trials. HNSCC have been underrepresented in multi-histology SABR trials. The GORTEC 2014-04 phase IIR study (NCT03070366) assesses impact on survival without definitive quality of life (QoL) deterioration (1y OSwoQoLloss) of omitting upfront systemic treatments in genuine oMets in HNSCC, often frail/heavily-pretreated, patients by using SABR alone as a more personalized metastatic burden-adapted & cost-saving strategy

Material/Methods:

With extracranial SABR being relatively new for most centers at protocol conception, center credentialing was performed before patient accrual using a benchmark case.

Patient inclusion criteria were PS 0- 2, life expectancy ≥6mo, controlled primary, 1 -3 PET-confirmed metastases of any site, cumulated PTV≤7cm. Chemotherapy consisted of the 2014 standard of care (SOC), i.e. Extreme. Fraction 53 or 5) size & total dose were standardized on oMet-size & proximity to OAR. Secondary endpoints were survival, PFS, definitive QoL deterioration & dimensions, toxicities, costs, correlation between plan quality by centralized retrospective individual case review (ICR) & local control. Salvage treatments were left to physician’s appreciation (repeat SABR allowed)