The Incidence and Patterns of Failure in Patients With Stage I/II Squamous Cell Carcinoma of the Oral Cavity (SCC-OC) Treated With Surgery Alone: Implications for Adjuvant Radiation Therapy

Abstract

Materials/Methods: From August 2001 through May 2012, 183 patients with cancer of the oral cavity were identified. Following exclusion of patients with prior head and neck cancer, non-squamous histology, no surgery, N2c or greater or M1 staging, or PORT plans unavailable or bilateral necks treated, 57 patients remained for analysis. Patient demographics, tumor, treatment, and outcome information were abstracted from the charts. Regional recurrence was estimated via Kaplan-Meier method and groups were compared via log-rank test. Results: Median follow-up from diagnosis was 21 months range. Primary sites included alveolar ridge (17.5%), buccal (8.8%), floor of mouth (21.1%), hard palate (5.3%), retromolar trigone (5.3%), and oral tongue (42.1%). Primary site was staged T1-2 in 59.6% and T3-4 in 40.4%. Of the cohort, 12% did not undergo neck dissection, while 18% underwent bilateral and 70% ipsilateral neck dissection. Concurrent chemotherapy was used in 26.3% of patients. Of the cohort, 34 (59.6%) patients were found to be clinically or pathologically node negative, out of which 22 (38.5%) were treated with PORT only to the primary site and 12 (21.1%) had primary site and ipsilateral neck PORT; actuarial regional control (RC) at 2 years was 78.6% and 80%, respectively. Of the 4 total regional failures in the PORT-primary only group, 1 patient had a regional only relapse, the remainder failed both locally and regionally. Of the 2 total regional failures in the PORT-primary/ipsilateral neck, both were in the treated neck, and one was both local and regional. Of the node positive patients, all 23 were treated with primary and ipsilateral PORT with 2 year RC rate of 94.7%. The one patient with regional failure relapsed in the treated neck. Conclusions: In selected patients with lateralized oral cavity squamous cell carcinoma it may be reasonable to exclude the N0 bilateral neck, or in ipsilateral node positive neck the contralateral neck, from the post-operative radiation therapy volumes. Author Disclosure: J.A. Contreras: None. N.G. Rao: None. A.M. Trotti: None. J.J. Caudell: None.