Impact of Postoperative Neck Radiotherapy Volumes on Long-Term Unstimulated Saliva Flow Following Primary Surgery and Ipsilateral Neck Dissection for Oral Cavity Squamous Cell Carcinoma

Claire M Rooney; Shao Hui Huang; Jie Su; Scott Bratman; John Cho; John de Almeida; Michael Glogauer; David Goldstein; Ezra Hahn; Ali Hosni; Andrew Hope; Jonathan Irish; John Kim; Brian O'Sullivan; Jolie Ringash; Anna Spreafico; Jillian Tsai; John Waldron; Christopher Yao; Erin Watson; Andrew McPartlin

doi:10.1002/hed.27988

Impact of Postoperative Neck Radiotherapy Volumes on Long-Term Unstimulated Saliva Flow Following Primary Surgery and Ipsilateral Neck Dissection for Oral Cavity Squamous Cell Carcinoma

Head Neck. 2024 Oct 30. doi: 10.1002/hed.27988. Online ahead of print.

Authors

Claire M Rooney¹, Shao Hui Huang¹, Jie Su², Scott Bratman¹, John Cho¹, John de Almeida³, Michael Glogauer^{4

5}, David Goldstein³, Ezra Hahn¹, Ali Hosni¹, Andrew Hope¹, Jonathan Irish³, John Kim¹, Brian O'Sullivan¹, Jolie Ringash¹, Anna Spreafico⁶, Jillian Tsai¹, John Waldron¹, Christopher Yao³, Erin Watson^{4

5}, Andrew McPartlin¹

Affiliations

¹ Department of Radiation Oncology, Princess Margaret Cancer Centre, Toronto, Canada.
² Department of Biostatistics, Princess Margaret Cancer Centre, Toronto, Canada.
³ Department of Otolaryngology-Head & Neck Surgery, Princess Margaret Cancer Centre, Toronto, Canada.
⁴ Department of Dental Oncology, Princess Margaret Cancer Centre, Toronto, Canada.
⁵ University of Toronto Faculty of Dentistry, Toronto, Canada.
⁶ Division of Medical Oncology, Princess Margaret Cancer Centre, Toronto, Canada.

PMID: 39474724
DOI: 10.1002/hed.27988

Abstract

Background: We investigate the association of postoperative radiotherapy (PORT) volumes and salivary function in oral cavity SCC (OSCC).

Methods: OSCC patients undergoing PORT 2005-2021 underwent modified Schirmer test (MST) pre-PORT, 6 and/or 12 months post-PORT. Hyposalivation rates were compared by PORT volumes. MVA identified predictors for chronic hyposalivation.

Results: Among 165 eligible patients, 88 (53%) received bilateral, 66 (40%) ipsilateral, and 11 (7%) no-neck (primary-only) PORT. Baseline characteristics were similar, except more N2b/N2c disease received bilateral PORT vs. ipsilateral or no-neck (60% vs. 36% vs. 0%, p < 0.001). Baseline hyposalivation was similar (26% vs. 30% vs. 18%, p = 0.67). Hyposalivation occurred more frequently in bilateral vs. ipsilateral vs. no-neck PORT at 6 (90% vs. 62% vs. 9%) and 12 months (90% vs. 48% vs. 0%) (both p < 0.001). On MVA, bilateral neck PORT and smoking predicted chronic hyposalivation.

Conclusion: Increasing PORT volumes predict saliva function recovery and chronic hyposalivation, informing treatment discussions.

Keywords: oral cavity cancer; postoperative radiotherapy; salivary hypofunction; unilateral; xerostomia.