Table 1.

Timeline of the clinical course.

Time	Clinical event	Key findings	Management/outcome
July 2022	Baseline cancer assessment	No tracheal or bronchial wall thickening on CT	Systemic anticancer therapy followed by tumor resection
March 2023	Onset of airway symptoms	Bilateral costal-arch pain, exertional wheeze; diffuse tracheal and bilateral bronchial wall thickening/calcification; FEV1 41% predicted	Pembrolizumab stopped; high-dose glucocorticoids and tofacitinib
April 2023	Initial response	Improved wheeze and reduced airway-wall thickening	Prednisone taper initiated
September 2023, during taper to prednisone 15 mg/day	Clinical relapse	FEV1 35.4% predicted; DLCO 57.3%; highest CD38+ and HLA-DR+ proportions among CD8+ T cells during the early disease course	Prednisone increased; tofacitinib stopped; abatacept 125 mg/week + methotrexate 20 mg/week
March 2024	Pulmonary infection	Pulmonary-function deterioration	Abatacept temporarily interrupted; tocilizumab subsequently added with prednisone and methotrexate
January 2025	Pulmonary infection with severe coughing	Pneumomediastinum	Escalation to interventional airway management
	Central airway intervention	Bilateral main-bronchial stent placement	Prednisone subsequently tapered to 12.5 mg/day; methotrexate 10 mg/week maintained
May 2026	Long-term follow-up	Both main-bronchial stents in situ; persistent diffuse airway-wall thickening/calcification but no obvious luminal stenosis; FEV1 50.1%, FVC 81.6%, DLCO 61.9%; PET-CT showed bilateral multifocal costal inflammation and no recurrent solid tumor	Continued surveillance; durable airway patency at 1 year