Outcome of systemic sclerosis associated interstitial lung disease treated with intravenous cyclophosphamide

Our objective was to audit the respiratory outcome, toxicity and long-term survival of systemic sclerosis associated interstitial lung disease (SSc-ILD) treated with intravenous (i.v.) cyclophosphamide. We ascertained whether i.v. cyclophosphamide associates with a better outcome in SSc-ILD diagnosed due to a decline in screening lung function than in those diagnosed due to respiratory symptoms. A retrospective case-note audit was carried out for SSc-ILD patients treated with i.v. cyclophosphamide between January 1999 and March 2009 at the Royal Derby, Kings Mill and Nottingham University Hospitals. Forced vital capacity (FVC) and transfer factor at 6, 12 months after starting i.v. cyclophosphamide were the primary end points. Kaplan-Meier curves were plotted to estimate survival. Thirty-seven i.v. cyclophosphamide treatment cycles were administered to 36 patients (27 women). Fourteen cycles associated with side effects and eight were terminated prematurely. SSc-ILD was diagnosed due to respiratory symptoms in 13 and in response to deteriorating screening pulmonary function test (PFT) in 24 instances. Overall, i.v. cyclophosphamide led to stabilisation in lung function. However, the FVC declined by 7% in SSc-ILD presenting with respiratory symptoms over 12 months. These patients had significantly lower FVC at 6 and 12 month than those with SSc-ILD diagnosed due to decline in screening lung function. The 5-year survival was 76.1% (overall), 62.9% (diagnosed due to respiratory symptoms) and 91.5% (diagnosed due to decline in screening lung function, p=0.05). I.V. cyclophosphamide stabilises lung function in individuals with SSc-ILD and may associate with better respiratory outcome in patients diagnosed on screening PFTs.