Pulmonary Outcomes After Autologous Stem Cell Transplant for Hodgkin Lymphoma

Autologous hematopoietic stem cell transplant (ASCT) may be curative therapy for pediatric patients with relapsed/refractory Hodgkin lymphoma (HL). Therapy for HL may involve pulmonary toxic modalities. Little information exists regarding pulmonary function in these patients post-ASCT. A retrospective chart review was performed for patients undergoing ASCT from February 2012 to December 2019. Lung disease was defined as a z-score ≤-1.7 in forced expiratory volume in the first second (FEV₁), forced vital capacity (FVC), total lung capacity (TLC), or diffusing capacity of lung for carbon monoxide. Descriptive and limited statistical analyses were performed. Twenty-eight patients were included. Median age at diagnosis was 15 (2 to 19) and was 17 (4 to 21) at ASCT. Twenty-three received radiation before ASCT. Fourteen received brentuximab before, and 9 after, transplant. Nineteen met criteria for lung disease post-ASCT. Sixteen had lung disease before ASCT. Longitudinal trends for pulmonary function testing parameters did not reach statistical significance, however, FEV₁, FVC, and TLC trended towards worsening immediately post-transplant. There was no statistically significant change in FEV₁, FVC, or TLC at 2 years as compared with pretransplant data, suggesting no substantial difference from baseline. Diffusing capacity of lung for carbon monoxide showed statistically significant improvement at the 2 year timepoint (P=0.03). This data reinforces the importance of close follow-up for these patients. Large cohort studies are necessary to identify risk factors so that possible mitigative strategies or alternate regimens could be used.