Outcomes linked to eligibility for stem cell transplantation trials in diffuse cutaneous systemic sclerosis

Objectives The aim of this study was to explore outcomes in a cohort of dcSSc patients fulfilling eligibility criteria for stem cell transplantation (SCT) studies but receiving standard immunosuppression. Methods From a large single-centre dcSSc cohort (n = 636), patients were identified using the published SCT trials' inclusion criteria. Patients meeting the trials' exclusion criteria were excluded. Results Of the 227 eligible patients, 214 met the inclusion criteria for ASTIS (Autologous Stem Cell Transplantation International Scleroderma), 82 for SCOT (Scleroderma: Cyclophosphamide Or Transplantation) and 185 for the UPSIDE (UPfront autologous haematopoietic Stem cell transplantation vs Immunosuppressive medication in early DiffusE cutaneous systemic sclerosis) trial, and 66 were excluded based on age >65 years, low diffusing capacity of the lungs for carbon monoxide (DLco), pulmonary hypertension or creatinine clearance <40 ml/min. The mean follow-up time was 12 years (S.d. 7). Among the eligible patients, 103 (45.4%) died. Survival was 96% at 2 years, 88% at 5 years, 73% at 10 years and 43% at 20 years. Compared with this 'SCT-eligible' cohort, those patients who would have been excluded from SCT trials had a worse long-term survival (97% at 2 years, 77% at 5 years, 52% at 10 years and 15% at 20 years, log rank P < 0.001). Excluded patients also had a significantly worse long-term event-free survival. Hazard of death was higher in patients with higher age at onset [hazard ratio (HR) 1.05, P < 0.001], higher ESR at baseline (HR 1.01, P = 0.025) and males (HR 2.12, P = 0.008). Conclusion SCT inclusion criteria identify patients with poor outcome despite current best practice treatment. Patients meeting the inclusion criteria for SCT but who would have been excluded from the trials because of age, pulmonary hypertension, poor kidney function or DLco <40% had worse outcomes.