Transoral Robotic Surgery for Oral Cancer: Evaluating Surgical Outcomes in the Presence of Trismus

TL;DR

This study finds that preoperative trismus in oral cancer patients undergoing robotic surgery is linked to worse long-term survival, despite similar short-term outcomes.

Contribution

The study identifies trismus as an independent predictor of long-term mortality in oral cancer patients undergoing TORS, despite non-inferior short-term surgical outcomes.

Findings

Trismus patients had similar short-term surgical outcomes to non-trismus patients, including operation time and hospital stay.

Trismus was independently associated with a 13-fold increased risk of mortality after adjusting for confounders.

There was no significant difference in disease-free survival between trismus and non-trismus groups.

Abstract

Trismus is a common complication in oral cancer patients that may influence surgical outcomes. This retrospective matched cohort analysis examined the influence of preoperative trismus on survival outcomes in 40 male Taiwanese oral cancer patients undergoing transoral robotic surgery (TORS). Through 1:1 propensity score matching, 20 trismus patients were compared to 20 non-trismus controls. TORS demonstrated comparable short-term surgical outcomes in trismus patients compared to non-trismus patients. There were no significant differences between groups in operation time, blood loss, margin status, flap reconstruction rates, duration of nasogastric tube feeding, or length of hospital stay. Analysis of long-term oncological outcomes demonstrated similar 5-year disease-free survival between groups, indicating comparable tumor control. However, trismus patients experienced significantly poorer 5-year overall survival. After adjusting for confounders, trismus independently conferred a 13-fold higher long-term mortality risk. Ultimately, this study highlights preoperative trismus as a harbinger of non-inferior short-term surgical outcomes, but diminished long-term survival in oral cancer patients treated robotically, even among those with equivalent tumor persistence following surgery. Further research should explore mechanisms linking trismus to mortality and approaches to improve outcomes in this population.

Trismus, defined as restricted mouth opening, is a common complication among Taiwanese oral cancer patients, especially those who chew betel quid. However, the impact of trismus on survival outcomes in oral cancer patients undergoing transoral robotic surgery (TORS) is unclear. This study aimed to investigate the associations between trismus and surgical outcomes in Taiwanese male oral cancer patients treated with TORS. We conducted a retrospective propensity score-matched cohort study of 40 Taiwanese male oral cancer patients who underwent TORS between 2016 and 2022. Overall, 20 patients with trismus were matched to 20 patients without trismus. TORS achieved similar operative and short-term clinical outcomes in trismus patients to non-trismus patients. There were no significant differences between groups in operation time, blood loss, margin status, flap reconstruction rates, duration of nasogastric tube feeding, or length of hospital stay. Kaplan–Meier and Cox proportional hazard regression analyses were performed to compare overall survival (OS) and disease-free survival (DFS) between the two groups. The overall survival (OS) rate at three years was significantly lower in patients with trismus than those without trismus (27.1% vs. 95.0%, log-rank p = 0.02). However, there was no significant difference in disease-free survival (DFS) rates between the trismus and non-trismus groups (36.6% vs. 62.7%, log-rank p = 0.87). After adjusting for confounders, trismus was independently associated with a 13-fold increased risk of mortality (adjusted HR 12.87, 95% CI 1.55–106.50, p < 0.05). In conclusion, trismus appears to be an independent prognostic factor for reduced long-term OS in Taiwanese male oral cancer patients undergoing TORS, though short-term surgical outcomes were non-inferior in the trismus patients. Further research is warranted to clarify the mechanisms linking trismus and survival in this population.

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