Head and Neck Cancer
SS 06 - H&N 1 - Current Topics in Post-Operative Radiation Therapy
42 - Risk of Contralateral Nodal Failure in Well Lateralized Early T-stage Oral Cavity Cancer Receiving Unilateral Treatment
Sunday, October 21
5:35 PM - 5:45 PM
Location: Room 006
Risk of Contralateral Nodal Failure in Well Lateralized Early T-stage Oral Cavity Cancer Receiving Unilateral Treatment
H. Liu1, L. Tam1, N. M. Woody2, J. J. Caudell3, C. A. Reddy2, A. I. Ghanem4, M. A. Schymick4, N. P. Joshi2, J. L. Geiger5, E. Lamarre6, B. B. Burkey6, D. J. Adelstein5, N. E. Dunlap7, F. Siddiqui4, S. Koyfman2, and S. Porceddu8; 1Princess Alexandra Hospital, Woolloongabba, Australia, 2Department of Radiation Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, 3H. Lee Moffitt Cancer Center and Research Institute, Department of Radiation Oncology, Tampa, FL, 4Henry Ford Health System, Detroit, MI, 5Department of Hematology/Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, 6Department of Otolaryngology, Head and Neck Institute, Cleveland Clinic, Cleveland, OH, 7University of Louisville Hospital, Department of Radiation Oncology, Louisville, KY, 8Princess Alexandra Hospital/University of Queensland, Brisbane, Australia
Purpose/Objective(s): Bilateral neck treatment is not routinely recommended to manage well lateralized early T-stage oral cavity squamous cell carcinoma (SCC) with or without ipsilateral confined neck disease. We sought to define the incidence and pathological predictors of contralateral nodal failure in this subset of patients. Materials/Methods: A collaborative database of patients with stage I-IVb (AJCC 7th edition) primary oral cavity SCC treated with primary surgical resection with or without adjuvant therapy between January 2005 and January 2015 was established from six academic institutions. From an overall patient population of 1282 patients, we identified patients with pathological stage T1-2N0-N2b SCC of the oral tongue/floor of mouth treated with primary surgery and unilateral neck dissection with or without radiation therapy (RT) to the primary site and/or unilateral neck. Patients with high risk features of positive margin/extracapsular extension, patients receiving bilateral neck treatment or had chemotherapy were excluded. Pathological risk factors including T-stage (T2 vs. T1) and tumor depth of invasion (>4mm vs. ≤4mm) associated with nodal involvement were analyzed by Fine and Gray regression analysis for association with contralateral nodal failure. Results: 176 patients were identified meeting inclusion criteria with a median of 65.9 months of follow up. The predominant pathological T- and N- stage was T1 (68%) and N0 (55%), respectively. Adjuvant radiation therapy was prescribed in 17% of patients. Ipsilateral, bilateral and contralateral neck were the first site of regional failure in 23, 2 and 7 patients, respectively. 2-year cumulative incidence of ipsilateral and bilateral/contralateral failure were 11.9% (95% CI 7%-16.8%) and 3.6% (95% CI 0.8%-6.5%), respectively. 5-year cumulative incidence of ipsilateral and bilateral/contralateral failure were 13.3% (95% CI 8.1%-18.5%) and 4.3% (95% CI 1.2%-7.4%), respectively. No pathological factors were identified to discriminate between patients for contralateral nodal failure, although pathological T2 vs. T1 stage approached significance, despite the low number of contralateral nodal failure (p=0.094, HR=2.98, 95% CI 0.83 – 10.64). Conclusion: In well lateralized early pathological T-stage oral cavity cancers with contralateral clinically node-negative neck, unilateral treatment is associated with low contralateral nodal failure rates. Omission of adjuvant RT to the contralateral neck is reasonable in small lateralized tumors.
Author Disclosure: H. Liu: None. N.M. Woody: None. J.J. Caudell: None. A.I. Ghanem: None. M.A. Schymick: None. D.J. Adelstein: None. N.E. Dunlap: Honoraria; Osler Institute. F. Siddiqui: Employee; Children's Hospital of Michigan. Research Grant; Varian Medical Systems, Inc. Honoraria; Wayne State University, American College of Radiology, Varian Medical Systems, Inc. Travel Expenses; Varian Medical Systems, Inc. Vice-Chairman or Operations; Department of Radiation Oncology, Henry Ford Hosp. Chair; ASTRO. Board Member; Henry Ford Health System Board of Governors. Committee Member; HFHS Bylaws and Governance Committee. S. Koyfman: Research Grant; Merck.