TF and bronchiolitis obliterans syndrome: Among patients with BO-MBC, compared to patients with ctDNA TF-low (median rwOS not reached), those with ctDNA TF-int had less favorable rwOS (median 31.05 months, HR: 2.19, 95% CI 1.1–4.35), as did those with TF-high (median 23.46 months, HR: 2.07, 95% CI 1.12–3.82) (Fig. 4B).