High Risk Oral Cavity Carcinoma Patient Outcomes Following Minimally Invasive Surgery and Adjuvant Radiation

Abstract

There has been a significant rise in the utilization of less invasive surgical treatment for oropharyngeal and oral cavity squamous cell carcinomas. Transoral laser microsurgery (TLM) has become an increasingly common procedure for primary treatment of oral cavity squamous cell carcinoma (OCSCC) due to improved cosmetic and functional outcomes. To date, little reported data exists addressing the outcomes of patients with OCSCC following TLM, especially those treated with adjuvant radiation therapy. The aim of this study was to retrospectively review the outcomes of patients with OCSCC treated with TLM and adjuvant radiation therapy. A single institutional retrospective chart review of patients diagnosed with OCSCC treated with TLM, with or without neck dissection, and adjuvant radiation therapy was conducted. All patients with a previous or concurrent diagnosis of oropharyngeal squamous cell carcinoma were excluded from our review. Treatment outcomes including local/regional control (LRC), overall survival (OS), and treatment toxicity were evaluated. These results were then compared to historical, published outcome data for treatment of OCSCC. Kaplan-Meier method was used to estimate 1, 3, and 5 year survival and freedom from local regional recurrence, and log-rank test was used to compare the freedom from events rate between groups. Thirty-nine patients meeting our inclusion criteria diagnosed with OCSCC from 1997 to 2015 were identified. Of these, 20 patients had AJCC stage III/IV disease at presentation, and the additional 19 patients had “high risk” features (68% recurrent disease, 32% depth of invasion ≥ 4mm, 21% perineural invasion, 11% positive margins, and 5% lymphovascular space invasion). The majority of patients (82%) received intensity modulated radiation therapy (IMRT), and 36% also received concurrent chemotherapy. Median follow-up for all patients was 26 months (range 2-155 months). The five year LRC rate was 65% overall, 58% for patients with recurrent disease, and 64% for patients with stage III/IV disease. The five year OS rate was 50% for advanced stage patients. The five year rates of LRC of 65% and OS of 41% in the “high risk” early T-classification cohort were consistent with historical rates of LRC(53 -69%) and OS (25 -63%). There was a 7.7% incidence of grade 3 osteoradionecrosis, which predominately occurred in the patients with recurrent disease, including one case of reirradiation. Our institutional outcomes of this retrospective cohort of patients with oral cavity cancer treated with TLM and radiation therapy are consistent with historical data. TLM should be considered a viable option to traditional wide local excision.