Ethanol Ablation of Ranulas and Risk Factor Analysis for Recurrence.

ABSTRACT

Importance Ethanol ablation (EA) was shown to be safe and effective for treating ranula, but few studies have assessed long-term outcomes and recurrence of ranula after EA. Objective: To evaluate the long-term outcomes and the risk factors for recurrence and receipt of subsequent surgery in patients who underwent treatment with EA for ranula. Design, Setting, and Participants: This case-series study was conducted at a single tertiary hospital and assessed patients who were treated with EA between July 2009 and March 2021. Among 70 consecutive patients, those with follow-up loss or who were followed up for less than 24 months were excluded. Exposures EA for ranula. Main Outcomes and Measures: The primary outcome was recurrence at last follow-up after single or multiple EA sessions. Secondary outcomes included receipt of subsequent surgery and the recurrence-free survival (RFS) rate after initial EA. Factors possibly associated with outcomes included patient age and sex; ranula site, type, diameter, volume, and echogenicity; the presentation-to-EA interval; parapharyngeal space extension; and sublingual gland herniation. Risk factors were identified on logistic regression analyses. Two-year RFS rates were analyzed for the initial cohort using the Kaplan-Meier method and compared by log-rank tests. Results: A total of 57 patients (mean [SD] age, 26.4 [12.1] years; 24 female individuals [42%]) who were followed up for a median of 57 months (range, 24-167 months) were included. The recurrence rate was 33% (n = 19), and 11 (19%) underwent subsequent surgery. Among patients with recurrence, 86% (31 of 36) experienced first recurrence within 12 months after initial EA. A presentation-to-EA interval of 12 months or longer was associated with an increased risk of recurrence (adjusted odds ratio [OR], 3.74; 95% CI, 1.01-13.82). No risk factors were significantly associated with subsequent surgery (highest OR in parapharyngeal space extension adjusted OR, 4.96; 95% CI, 0.94-26.35). Among the initial cohort of 70 patients, 2-year RFS was lower in a maximum diameter of ranula of 5 cm or greater than less than 5 cm (24% [95% CI, 7%-41%] vs 50% [95% CI, 34%-66%]; difference, 26% [95% CI, -4% to 56%]; log-rank test, P = .02). Conclusions and Relevance This case-series study found that the recurrence rate of ranula after EA was 33%. A presentation-to-EA interval of 12 months or longer may be a risk factor for recurrence, suggesting that early intervention with EA might minimize recurrence. Most first recurrences occurred within 12 months after EA, with a maximum diameter of ranula of 5 cm or greater being a possible risk factor.