How slow should we go? Variation and outcomes of steroid tapering for immunotherapy-related toxicities in gynecologic cancer

OBJECTIVE: This study examined both National Comprehensive Cancer Network (NCCN) guideline concordance and steroid taper duration with clinical outcomes in patients with gynecologic malignancies experiencing immune-related AEs. METHODS: This single-institution retrospective cohort included patients with gynecologic malignancies treated with immune checkpoint inhibitor (ICI) from August 2016 to September 2025 who developed grade 3 or 4 immune-related AEs requiring systemic steroids. Clinical and steroid treatment data were abstracted. NCCN guideline concordance and outcomes were assessed. RESULTS: 63 patients contributing 73 steroid tapers were included. Most patients had endometrial (41.3%), cervical (27.0%), or ovarian cancer (23.8%), and pembrolizumab was the most used ICI (74.6%). 46 tapers (63.0%) were NCCN guideline concordant and 27 (37.0%) were NCCN guideline discordant, with discordance most often driven by taper length and premature initiation. 14 (19.2%) were < 28 days, and 59 (80.8%) were ≥ 28 days. NCCN discordant tapers were more likely to require additional supportive medications for irAE management (e.g. secondary steroids) than concordant tapers (81.5% vs 56.2%, p = 0.0300). NCCN concordance was associated with longer time to ICI restart (56 vs 21 days, p = 0.0241). Tapers <28 days were more likely to require additional supportive medications (100% vs 57.6%, p = 0.0027) and steroids (35.7% vs 8.4%, p = 0.0253) than tapers ≥28 days. Tapers ≥28 days were associated with higher rates of ICI discontinuation due to toxicity (59.3% vs 28.6%, p = 0.0381). Rates of hospitalization, ICU admission, and AE resolution did not differ by NCCN concordance or taper duration. CONCLUSIONS: Corticosteroid taper practices varied substantially in patients with gynecologic malignancies experiencing severe irAEs; shorter and guideline-discordant tapers were associated with greater treatment escalation and steroid reinitiation.