TNM 8 staging is a better prognosticator than TNM 7 for patients with locally advanced oral cavity squamous cell carcinoma treated with surgery and post-operative radiotherapy

• Published in: Radiotherapy and oncology 2021-07, Vol.160, p.54-60
• Main Authors: Sambasivan, Khrishanthne, Sassoon, Isabel, Thavaraj, Selvam, Kennedy, Robert, Doss, Gowardhanan, Michaelidou, Andriana, Odell, Edward, Sandison, Ann, Hall, Gillian, Morgan, Peter, Collins, Lisette Hannah Claire, Lyons, Andrew, Cascarini, Luke, Fry, Alastair, Oakley, Richard, Simo, Ricard, Jeannon, Jean-Pierre, Petkar, Imran, Reis Ferreira, Miguel, Kong, Anthony, Lei, Mary, Guerrero Urbano, Teresa
• Format: Article
• Language: English
• Subjects: Head and neck cancer; Post operative radiotherapy; Survival outcomes; TNM 8 staging
• ISSN: 0167-8140; 1879-0887
• DOI: 10.1016/j.radonc.2021.04.003

•This is an analysis of stage III-IV oral cancer patients, comparing TNM 8 to TNM 7.•TNM 8 is a better prognosticator for OS, DFS and early disease recurrence.•On MVA, TNM 8 stage, margin status and performance status affect overall survival.•Patients aged < 60 years who smoked less were more likely to recur within 12 months. To assess TNM 8 staging in discriminating overall survival (OS) amongst patients with locally advanced oral cavity squamous cell carcinoma (OCSCC) treated with surgery and post-operative radiotherapy (PORT), compared to TNM 7. Data from OCSCC patients treated with surgery and PORT between January 2010 and December 2018 were reviewed. Demographics, tumour characteristics and treatment response data were collected, and patients staged according to both TNM 7 and TNM 8. OS and disease free survival (DFS) were estimated using the Kaplan Meier method. Univariate and multivariable analyses were conducted for factors affecting OS, DFS and early disease recurrence within 12 months. Overall 172 patients were analyzed. Median follow up was 32 months for all patients and 48 months for surviving patients. TNM 8 staging demonstrated significant stratification of OS and DFS amongst the entire cohort, whereas TNM 7 staging did not. On multivariable analysis, TNM 8 stage, performance status (PS) and a positive surgical margin were prognostic for OS. Looking at disease recurrence within 12 months, TNM 8 stage IVB, presence of lymphovascular invasion (LVSI), younger age and lesser smoking history were predictive factors on multivariable analysis. TNM 8 is a good development of its predecessor in terms of predicting survival for patients with locally advanced OCSCC. We have also identified younger age (