ESTRO 2024 - Abstract Book

S1406

Clinical - Head & neck

ESTRO 2024

Results:

A total of 455 patients with locoregionally advanced oropharyngeal cancer treated definitively with CRT were available for analysis. Median age was 61 (range 35 – 86), 90.3% were men (n=411), and 91.2% were p16 or HPV positive (n=415). Median dose was 7000 cGy (range 3200 – 7520 cGy) at a median fraction size of 200 cGy (200 – 240 cGy), with 85.3% of patients (n=390) receiving cisplatin as the concurrent systemic therapy. Of the entire cohort, 20.9% (n=95) were hospitalized during or within 3 months of CRT. Other than mean volume of high dose PTV (173.07 cc vs 198.87 cc, p = 0.042), no other demographic, tumor, or treatment factor were significant for hospitalization. Mean dose to the larynx (mean 41.1 Gy vs 45.5 Gy, p<0.001), mandible (mean 32.4 Gy vs 34.8 Gy, p=0.01), superior pharyngeal constrictor (mean 55.1 Gy vs 58.0 Gy, p=0.038), middle pharyngeal constrictor (mean 47.3 Gy vs 54.4 Gy, p<0.001), inferior pharyngeal constrictor (mean 37.6 Gy vs 42.8 Gy, p<0.001), ipsilateral parotid (mean 33.1 Gy vs 36.0 Gy, p=0.002), ipsilateral submandibular gland (mean 64.8 Gy vs 67.0 Gy, p=0.01), and contralateral submandibular gland (mean 45.2 Gy vs 50.4 Gy, p=0.003) were associated with hospitalization. On binary logistic regression only the middle pharyngeal constrictor (OR 1.068, 95% CI 1.03 – 1.109, p<0.001) and ipsilateral parotid (OR 1.047, 95% CI 1.013 – 1.082, p=0.007) remained significant.

Conclusion:

Hospitalization during concurrent systemic therapy and radiation therapy for locoregionally advanced oropharyngeal cancer occurs in 20.9% of patients. Reduction of doses to the middle pharyngeal constrictor and ipsilateral parotid may help reduce the risk of hospitalization.

Keywords: Oropharyngeal cancer, Hospitalization, Dosimetry

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Poster Discussion

Circulating cell-free HPV DNA correlates with disease volume in p16 positive OPSCC

DAVID NOBLE 1,2 , Victoria Salati 3 , Devraj P Srinivasan 2 , Joanna Mackenzie 2 , Martyna Adamowicz 4 , Christelle Robert 4 , Lara M Carey 4 , Kate Cuschieri 5 , Brendan Conn 6 , Ashley Hay 3 , Timothy J Aitman 4 , Iain J Nixon 3 1 Edinburgh Cancer Research Centre, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, United Kingdom. 2 Edinburgh Cancer Centre, Western General Hospital, NHS Lothian, Edinburgh, United Kingdom. 3 Department of Otolaryngology and Head and Neck Surgery, Lauriston Place, NHS Lothian, Edinburgh, United Kingdom. 4 Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, United Kingdom. 5 Scottish HPV Reference Laboratory, Department of Laboratory Medicine, Royal Infirmary of Edinburgh, NHS Lothian, Edinburgh, United Kingdom. 6 Department of Pathology, Royal Infirmary of Edinburgh, NHS Lothian, Edinburgh, United Kingdom

Purpose/Objective: