van den Hombergh WMT, et al. - Presuming that treatment with cyclophosphamide (CYC) might be more effective in the inflammatory phase, experts evaluated that whether the extent of inflammation, as assessed by the proportion of ground glass compared to fibrosis, systemic sclerosis (SSc) disease duration, the extent of interstitial lung disease (ILD), or baseline diffusion capacity of the lungs (DLCO) <60%, modified the effect of intravenous CYC pulse therapy (750 mg/m²) on pulmonary function (as measured by forced vital capacity (FVC), diffusion capacity of the lungs (DLCO)) in SSc-interstitial lung disease (ILD) patients, after 12, 24, and 36 months. In patients with SSc-ILD, pulmonary function was stabilized with the treatment with CYC followed by maintenance therapy over a 3-year period. The effect of CYC on pulmonary function was not affected by the extent of ILD, proportion of ground glass, SSc disease duration, and baseline DLCO <60%.