ESTRO 2025 - Abstract Book

S1040

Clinical – Head & neck

ESTRO 2025

Locoregional recurrence was observed in 45 (25,4%) patients with 72 recurrent lesions. Median time to locoregional recurrence was 6 months: 37 patients relapse in the first year (n=6 HPV+ and n=31 HPV-), 5 patients in the second year and 3 patients afterwards (see Fig.1).Twenty-nine patients developed locoregional recurrence alone, 16 patients had both distant and locoregional and 15 patients had only distant recurrence. Local recurrence rates were different in HPV-positive and HPV-negative patients: 14% (7/50 patients) HPV+ and 31% (38/122) HPV-. Patterns of locoregional relapse after definitive RT were as follows: 46 recurrences in high-dose volume; 11 recurrences in the peripheral high-dose volume; 8 recurrences in the central elective volume; 4 recurrences in the peripheral elective volume; and 3 recurrences outside the irradiated volume (See Table 1). Conclusion: Recurrence in the majority of the patients occurred in the primary and regional lymph nodes located in high dose area. Rates und patterns of relapse were different according to HPV status.

Keywords: recurrence, definitive RT

References: Mohamed ASR, Cardenas CE, Garden AS, et al. patterns-of-failure guided target volume definition for head and neck cancer patients: FDG-PET and dosimetric analysis if dose escalation candidate subregions. Radiother Oncol 2017;124(2):248-55.

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Digital Poster Radiotherapy for oropharyngeal cancer with daily adapt-to-shape workflow on MR-linac: preliminary outcomes and comparison with helical tomotherapy Andrea Emanuele Guerini 1 , Michela Buglione di Monale 1 , Stefania Nici 2 , Stefano Riga 2 , Ludovica Pegurri 3 , Eneida Mataj 1 , Albert Sakiri 1 , Davide Farina 4 , Marco Ravanelli 4 , Paolo Rondi 4 , Gianluca Cossali 1 , Davide Tomasini 1 , Luca Triggiani 1 , Giorgio Facheris 1 , Luigi Spiazzi 2 , Stefano Maria Magrini 1 1 Radiation Oncology, Università degli Studi di Brescia, Brescia, Italy. 2 Medical Physics, ASST Spedali Civili di Brescia, Brescia, Italy. 3 Radiation Oncology, ASST Spedali Civili di Brescia, Brescia, Italy. 4 Radiology Unit, Università degli Studi di Brescia, Brescia, Italy