Risk factors for adverse events associated with endoscopic submucosal dissection for superficial pharyngeal cancer.

BACKGROUND: Superficial pharyngeal cancer can be treated with curative intent while preserving function using minimally invasive peroral endoscopic resection techniques such as endoscopic submucosal dissection (ESD). However, severe adverse events occasionally occur, such as laryngeal edema requiring temporary tracheotomy and fistula formation. Therefore, we investigated the risk factors for adverse events associated with ESD for superficial pharyngeal cancer. METHODS: This retrospective observational study was conducted at a single institution, and 63 patients who underwent ESD were enrolled. The primary outcome was the risk factors for adverse events associated with ESD. The secondary outcomes were adverse events associated with ESD and their frequency. RESULTS: The overall adverse event rate was 15.9% (10/63). The incidence of laryngeal edema requiring prophylactic temporary tracheotomy was 11.1%, while laryngeal edema requiring emergency temporary tracheotomy, postoperative bleeding, aspiration pneumonia, fistula, abscess, and stricture formation occurred in 1.6% of patients, respectively. Logistic regression analyses showed that a history of radiotherapy for head and neck cancer was a risk factor for adverse events (odds ratio [OR], 16.67; 95% confidence interval [CI], 3.04-91.34; p = 0.001). After adjusting the model for differences in the baseline risk factors using the inverse probability of treatment weighting method, the adverse events were found to increase in association with a history of radiotherapy for head and neck cancer (OR, 39.66; 95% CI,5.85-268.72; p < 0.001). CONCLUSION: History of radiotherapy for head and neck cancer is an independent risk factor for adverse events associated with ESD for superficial pharyngeal cancer. Among adverse events, laryngeal edema requiring prophylactic temporary tracheotomy was particularly high.