Prior anti-PD-1 therapy as a risk factor for life-threatening peri-engraftment respiratory distress syndrome in patients undergoing autologous stem cell transplantation.

Peri-engraftment respiratory distress syndrome (PERDS) is a kind of potentially life-threatening complication of autologous stem cell transplantation (ASCT). PERDS is characterized by fever, dyspnea, and hypoxemia during neutrophil engraftment. In order to identify the high-risk factors for PERDS, we retrospectively analyzed 260 patients with lymphoma undergoing ASCT in recent five years. The conditioning regimen was BuCyE (busulfan, cyclophosphamide, and etoposide). There were 16 patients (6.1%) diagnosed as PERDS. In multivariate analysis, prior anti-programmed death-1 (PD-1) therapy (hazard ratio [HR] = 8.852, 95% confidence interval [CI]: 2.954-26.527, P < 0.001) and history of pulmonary disease (HR = 3.718, 95% CI: 1.197-11.545, P = 0.023) were independent risk factors for PERDS. Patients with prior anti-PD-1 therapy (n = 31) had higher incidence of engraftment syndrome (77.4% vs. 33.4%, P < 0.001), PERDS (25.8% vs. 3.5%, P < 0.001), and transplant-related mortality (9.7% vs. 0.4%, P < 0.001), compared with those without prior anti-PD-1 therapy (n = 229). Subgroup analysis showed that sintilimab seemed to be associated with higher incidence of PERDS (42.9% vs. 11.8%, P = 0.06) compared with non-sintilimab group (pembrolizumab or toripalimab). C-reactive protein might be a feasible early predictor for PERDS. In conclusion, our study suggests that prior anti-PD-1 therapy may be a strong risk factor for life-threatening PERDS in patients with lymphoma undergoing ASCT.