Efficacy of Sapylin in endoscopic thyroid cancer surgery: a double-blind, randomized, controlled trial

Postoperative exudation after thyroidectomy can compromise healing. Although Sapylin (Group A Streptococcus pyogenes) promotes wound repair, its efficacy and safety in endoscopic thyroid cancer surgery remain unclear. This randomized controlled trial evaluated Sapylin's impact on postoperative drainage and complications.

Ninety-two patients were randomized (1:1) to receive 10 KE Sapylin in 20 ml saline (treatment group) or saline alone (control group) via the drainage tube. Endpoints included drainage volume, inflammatory markers, and assessment of short-term and long-term complications, specifically vocal function.

The treatment group showed significantly lower drainage volumes on Day 1 (P = 0.026), Day 2 (P = 0.014), and in total (P = 0.009). Inflammatory markers were transiently elevated in the treatment group (P < 0.01) but normalized rapidly. Notably, the incidence of hoarseness was significantly higher in the treatment group (16 vs. 6 cases, P = 0.015). Crucially, long-term follow-up confirmed that all cases of hoarseness were transient. All affected patients achieved complete recovery of vocal cord mobility, and no cases of permanent vocal cord paralysis were observed.

Sapylin significantly reduces postoperative drainage volume following endoscopic radical thyroidectomy. However, its application is associated with a systemic inflammatory response and an increased risk of transient postoperative hoarseness. Although this nerve dysfunction is reversible, given the potential for neural irritation, its application should be restricted or approached with extreme caution, carefully weighing the benefits of drainage reduction against the risk of transient hoarseness.

This study was registered with the Chinese Clinical Trial Registry (accessible by logging in at https://www.chictr.org.cn/ ), registration number ChiCTR2500103444.