Background: To prospectively study changes in lung function in Hodgkin's lymphoma (HL) patients and to explore predictors for these changes over time.
Methods: In all, 52 patients with HL receiving bleomycin-based chemotherapy with (n = 23) or without (n = 29) mediastinal radiotherapy were enrolled. Pretreatment pulmonary function tests were carried out. These were repeated at 1 month, 6 months, and 1 year after therapy.
Results: With chemotherapy alone, the median %DLCO declined significantly at 1 month but returned to baseline by 6 months. The median %DLCO did not further decrease with radiotherapy, but remained persistently reduced at 1 year. In patients who received radiotherapy, having >33% of lung volume receive 20 Gy (V20) and a mean lung dose (MLD) of >13 Gy significantly predicted for persistently reduced %DLCO at 6 months (P = 0.035). Smoking significantly predicted for a persistently reduced %DLCO at 1 year (P = 0.036). On multivariable analysis, significant predictors for decline in %DLCO at 1 year were higher baseline %DLCO (P = 0.01), higher MLD (P = 0.02), and a smoking history (P = 0.02).
Conclusions: Several factors contribute to decline in %DLCO in HL patients who received bleomycin-based computed tomography. The identification of threshold radiation dosimetric parameters for reduced lung function may provide guidance in the radiation planning of these patients.