Ethanol Ablation of Ranulas and Risk Factor Analysis for Recurrence

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.

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.

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.

EA for ranula.

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.

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).

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.