(0729) Site-Specific Postoperative Complications Following Primary Surgery as Treatment for Oropharyngeal Squamous Cell Carcinoma

Introduction: Transoral robotic surgery (TORS) for primary tumors of the base of tongue and tonsil may result in different postoperative outcomes due to their inherent anatomical location, but this distinction is unclear. This study compares postoperative outcomes of different subsites of oropharyngeal cancer after TORS and neck dissection.

Methods: This study queried the TriNetX US database to identify oropharyngeal squamous cell carcinoma patients with subsequent TORS and neck dissection. Patients with M1 disease and diagnoses greater than 20 years ago were excluded. Patients were stratified by subsite – base of tongue (BOT SCC) or tonsil (tonsil SCC) – and matched by age, race, ethnicity, T-stage, and N-stage prior to comparison. Association with infection, dehiscence, dysphagia, gastrostomy, tracheostomy, respiratory failure, and inpatient admission were measured at 3 months, 6 months, and 1-year post-operation.

Results: A total of 34,988 patients were initially identified with unspecified squamous cell carcinoma of the oropharynx, and 426 patients met eligibility criteria after matching (n= 213 for BOT SCC, n = 213 for tonsil SCC). The most frequent complications of both BOT SCC and tonsil SCC cohorts included dysphagia (55.7% vs 56.5%) and gastrostomy tube dependence (38.3% vs 31.7%). There were no significant differences of any outcomes at the 3-month timepoint. At 6 months, the BOT SCC cohort had higher risk of infection [OR = 2.338, 95% CI = (1.079, 5.066)] and tracheostomy dependence [OR = 1.575, 95% CI = (1.013,2.449)] compared to the tonsil SCC cohort. Both the BOT SCC cohort and tonsil SCC cohort were at risk of readmission within 1-year of surgery (21% vs 21%).

Conclusions: TORS and neck dissection for BOT SCC was associated with a greater risk for postoperative infection and tracheostomy dependence than that of tonsil SCC, with no significant impact on risk of readmission.