2759 - Locally Advanced Oral Cavity Cancer Treated with Definitive Chemoradiation: An Organ Preservation Strategy over Three Decades
Presenter(s)
M. J. Gutman1, L. M. Serra1, C. C. Foster2, R. Philips3, H. Arshad3, E. A. Blair3, N. Agrawal3, N. Choudhury4, A. J. Rosenberg4, A. Pearson4, A. Juloori1, D. J. Haraf1, E. E. Vokes4, and R. R. Katipally1; 1Department of Radiation and Cellular Oncology, University of Chicago, Chicago, IL, 2Department of Radiation and Cellular Oncology, The University of Chicago Medicine, Chicago, IL, 3Section of Otolaryngology-Head and Neck Surgery, Department of Surgery, University of Chicago, Chicago, IL, 4Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL
Purpose/Objective(s): Locally advanced oral cavity squamous cell carcinoma (OC-SCC) is traditionally treated with surgery, but there remains an unmet need to evaluate contemporary outcomes for curative non-operative management with the goal of organ or functional preservation. Here, we present a pooled analysis of locally advanced OC-SCC receiving definitive chemoradiation over a thirty-year period.
Materials/Methods: Patients with locally-advanced stage III-IV OC-SCC treated with concomitant CRT between 1994-2023 at a single institution were retrospectively analyzed (77% treated on prospective trials). Patients were selected for non-operative management after comprehensive multi-disciplinary evaluation with Head & Neck Surgery (including assessment of anticipated functional outcome), Medical Oncology, and Radiation Oncology. Radiotherapy (RT) was delivered once or twice daily to a prescription dose of 70–75 Gy, most commonly utilizing the TFHX regimen (87% of patients) in a week on/week off fashion with concomitant fluorouracil and hydroxyurea with other third agents (generally paclitaxel). 62% received induction chemotherapy (generally carboplatin/paclitaxel-based), with neoadjuvant/adjuvant immune checkpoint inhibitors (IO) in 12 (6%) patients. Locoregional control (LRC), distant control (DC), progression-free survival (PFS), overall survival (OS), osteoradionecrosis (ORN), and gastrostomy-tube dependence were clinically annotated.
Results: 191 patients met inclusion (median age 57 years, 35% female, 83% T3/T4, 70% =N2, 93% stage IV disease, 50% oral tongue, median follow-up time of 3.7 years). At 5-years, the LRC was 77% (95% CI, 70% to 83%), DC was 87% (95% CI, 81% to 92%), PFS was 57% (95% CI, 51% to 66%), and OS was 62% (95% CI, 55% to 59%). Outcomes did not differ between patients treated in the last decade (contemporary cohort) versus prior (historical cohort) [log-rank P > 0.05]. Among locoregional failures, 57% were in the primary site, 27% were regional alone, and 10% were combined locoregional (6.7% unable to be specified). T4 tumors (P = 0.012) and node positivity (P = 0.012) were associated with worse LRC, but not DC (P > 0.05). Neoadjuvant/adjuvant IO was not associated with LRC (P = 0.47) or DC (P = 0.37). In the subset with ORN data available, 18% developed ORN requiring surgical treatment (including debridement) at median onset time of 3.2 years. 5-year ORN was lower in the contemporary cohort (9% vs. 20% in the historical cohort), albeit limited by a shorter follow-up period. Prolonged G-tube (i.e. present at last follow-up) was required in 18%.
Conclusion: Locally advanced oral cavity cancer can be curatively treated with chemoradiation with excellent outcomes and potentially facilitate organ/functional preservation in carefully selected patients, especially where surgery (e.g. total glossectomy) would be extensive. Future studies are warranted to identify which patients are most likely to benefit from a non-operative approach and optimize patient selection.