Definitive Management of Early Stage Oropharyngeal Carcinoma: A Comparison of Long Term Outcomes Following Transoral Surgery or Definitive Chemoradiation

Abstract

Early stage oropharyngeal carcinoma (ES-OPC) may be managed with definitive chemoradiation (CRT) or surgical resection and adjuvant therapy. Transoral surgery (TOS) is a modern technique in the surgical management of OPC. Here we review our institution’s long term outcomes of ES-OPC treated with CRT or TOS and adjuvant therapy with the hypothesis that oncologic outcomes would be similar, but with distinct toxicity profiles. T0-2 N0-2b M0 (AJCC 7) OPC treated with CRT or TOS, neck dissection and adjuvant (C)RT were included. Kaplan Meier curves and log rank test compared overall (OS) and progression free survival (PFS). Toxicity was compared at acute (< 6 months), intermediate (6 – 18 months), and late (> 18 months) time points with the Kruskal Wallis test using prospectively collected patient reported outcome measures of the MD Anderson Dysphagia Inventory (MDADI), Sydney Swallow Questionnaire (SSQ), and Xerostomia Questionnaire (XQ). 204 patients were included: 97 CRT, 71 TOS-RT, and 36 TOS-CRT. Median follow up (fu) was 2.61 years and the majority (98%) had human papilloma virus associated OPC. Patients treated with CRT had larger primary tumors (T2: CRT - 60.8%, TOS-RT 26.8%, TOS-CRT 33.3%, p <0.001) and more advanced nodal disease (N2: CRT – 90.7, TOS-RT – 66.7%, TOS-CRT 66.7%, p <0.001). At last fu 6 deaths occurred and therefore median OS was not reached or different between groups (p=0.19). Similarly, median PFS was not reached for any group, however time to progression was longer with TOS (p=0.021); Two year PFS with TOS-RT was 98.5%, compared to 96.4% with TOS-CRT and 87.8% with CRT. Most relapses were in the neck or distantly. Out of 14 relapses, only two were local, both in the CRT group. Acute toxicities were higher with CRT. Median acute SSQ was 357.6 for CRT, 264.2 for TOS-CRT, and 201.8 for TOS-RT (p = 0.002). Median acute MDADI was lower with CRT (72.6) compared to TOS-CRT (75.8) and TOS-RT (77.9; p=0.13). The majority in all groups had normal swallow function with long term fu. However, late toxicity appeared higher with TOS-CRT (Table) compared to CRT and TOS-RT (p=0.02). Late toxicity also varied by primary site: base of tongue (BOT) primaries had worse swallow function with TOS-RT compared to CRT (p=0.05) while tonsil primaries had better swallow function following TOS-RT compared to CRT (Table, p =0.002). Late XQ was improved with TOS-RT (Table, p=0.01). Rates of relapse in ES-OPC following CRT or TOS are low. Long term toxicity appears to vary by treatment type and tumor location and should be considered in the use of TOS and future treatment de-intensification trial designs.Abstract 2949; Table 1All patientsCRTTOS-RTTOS-CRTp-valueSSQ104.9137.4204.60.06MDADI90.592.186.30.02XQ31.318.128.80.01BOTSSQ99.2211.91340.05MDADI90.588.495.80.02TonsilSSQ125.981.1204.60.002MDADI85.395.881.1<0.001 Open table in a new tab