Introduction Pulmonary complications are a prominent cause of morbidity and mortality following stem cell transplant (SCT) accounting for more than 30% of transplantation-related deaths. Exposure to agents associated with pulmonary toxicity (bleomycin, radiotherapy) is common in patients with Hodgkins lymphoma (HL) for whom SCT is a standard approach at relapse, making them potentially more susceptible to pulmonary toxicity post-transplant. Sequential pulmonary function tests (PFTs), are sensitive measures of lung disease after SCT allowing early diagnosis and treatment, thereby improving outcome. We report a retrospective analysis of serial PFT monitoring of patients with relapsed HL who underwent SCT.
Methods Patients were assessed with serial PFTs pre (T=0) and post SCT (initially 6 weeks and then 3 monthly thereafter). Standardised PFTs were expressed as a percentage of the pre-transplant value (100%). Tests were carried out by the same personnel, to ensure standardisation and eliminate variability in patient performance.
Results 29 patients were studied with median age at SCT of 35.3 years (range 17.1–60.7 years). Pre-transplant conditioning utilised chemotherapy (predominantly BEAM—carmustine, etoposide, cytarabine, melphalan) for all except two transplants (TBI based). The median follow up was 18 months (range 3–117 months) and a median of four PFTs performed (range 2–16). FEV1 was decreased >10% in 13/29 and >20% in five of these patients, FVC was reduced >10% in 12/29 and >20% in 5/29. TLCO reduction >10% was observed in 21/29 and >20% in 13/29 and KCO decrease >10% occurred in 18/29 and >20% 9/29 patients. Reductions in TLCO/KCO occurred earlier than FEV1/FVC reductions (median 1.5 and 3 months respectively). Recovery of lung function occurred in >50% of patients who had repeat investigation within 24 m. Significant reduction of TLCO/KCO was observed in only 1/10 patients who had PFTs >3 years from transplant (Abstract P134 Figure 1).
Conclusion PFTs initially deteriorated in a significant proportion of patients but tended to recover by 30–40 months post transplant. This could be due to pulmonary toxicity from conditioning therapy, post-transplant lung injury, or a combination of both. During the first 3 years post-transplant, patients have an increased risk of developing pulmonary complications providing a rationale for serial PFTs.