Systemic Immunosuppression to Reduce Surgical Intervention in ANCA ‐Negative Subglottic Stenosis

OBJECTIVES: Idiopathic subglottic stenosis (iSGS) is a disease of unclear etiology and predictable phenotype. While surgical dilatation is the mainstay of management, a subset of patients experiences recurrent disease with minimal long-term symptomatic relief. This study evaluates whether systemic immunosuppression alongside surgical management is an effective adjunctive treatment strategy in this patient cohort. METHODS: A retrospective study was conducted on patients at a tertiary airway center with isolated SGS. The cohort was categorized into idiopathic SGS and granulomatosis with polyangiitis SGS (GPA-SGS). A sub-cohort of iSGS patients with aggressive disease was classified as "atypical-SGS." Both atypical-SGS and GPA-SGS cohorts received systemic immunosuppression alongside surgery and disease activity was assessed before and after immunosuppression through the inter-dilation interval (IDI). RESULTS: Sixty patients were included: 33 with iSGS, 20 with GPA-SGS, and 7 with atypical SGS. The iSGS cohort had an indolent disease course, with a median IDI of 17.6 months (IQR 16.0-25.0); none received immunosuppression. GPA-SGS patients demonstrated significantly shorter intervals prior to treatment (median 8.9 months, IQR 3.8-28.0), improving to 26.0 months (IQR 9.3-36.7) following immunosuppression (p = 0.0027). Similarly, in atypical SGS, IDI increased from 7.6 months (IQR 6.8-12.0) to 27.8 months (IQR 12.0-49.0) post-treatment (p = 0.0496). No significant adverse events were observed. CONCLUSION: Atypical SGS represents a diagnostically ambiguous yet clinically aggressive subset of SGS. Systemic immunosuppression, typically reserved for GPA, may prolong disease-free intervals in both GPA-SGS and atypical SGS. These findings support multidisciplinary evaluation and consideration of immunotherapy in frequently recurring, ANCA-negative SGS.