Hematopoietic stem cell transplantation (HSCT) and cyclophosphamide (CYC) are treatment options for progressive interstitial lung disease associated with systemic sclerosis (SSc-ILD). The aims of our retrospective observational study were to evaluate: 1) the evolution of SSc-ILD assessed by high-resolution computed tomography (HRCT) in SSc patients treated with HSCT. A group of patients treated with CYC was included as frame of reference; 2) how pulmonary function tests (PFTs) associate with HRCT findings; 3) which factors predict ILD reduction.
We semi-quantitatively scored total ILD extent, reticulations and ground glass opacities (GGO) on baseline and 1-year HRCTs of SSc patients treated with HSCT or CYC. Linear association between HRCT and PFT changes, and predictors of ILD improvement, were studied.
We included 51 patients (HSCT n=20; CYC n=31). Mean change in total ILD score was -5.1% (95%CI -10.2 to 0.0) in HSCT (p=0.050), and -1.0% (95%CI -4.3 to 2.3) in CYC group (p=0.535). For all patients, evolution of HRCT scores was weakly associated with relative changes in PFTs. In univariate logistic regression, higher GGO and total ILD scores, and lower diffusing capacity of the lungs for carbon monoxide at baseline (DLCO), predicted improvement of ILD extent after treatment, but a multivariable model could not be built to assess independency of predictors.
One year after treatment with HSCT, a non-significant, but clear, reduction of SSc-ILD extent was observed. Changes in PFTs were associated with changes in HRCT scores but the correlation was weak and cannot be considered conclusive.