Reduced lung function in leukaemia patients undergoing bone marrow transplantation

Area of Science:

• Oncology
• Pulmonary Medicine
• Radiotherapy

Background:

• Allogeneic bone marrow transplantation is a curative treatment for certain leukemias.
• Conditioning regimens often involve high-dose chemotherapy and total body irradiation (TBI).
• Pulmonary complications are a significant concern following TBI.

Purpose of the Study:

• To assess the impact of TBI as part of the Seattle conditioning protocol on lung function in leukemia patients.
• To evaluate changes in pulmonary parameters, specifically CO diffusion capacity and vital capacity, post-bone marrow transplantation.

Main Methods:

• 20 patients with leukemia in remission or early relapse underwent allogeneic bone marrow transplantation.
• Conditioning involved high-dose cyclophosphamide and 8 Gray TBI delivered via a linear accelerator.
• Lung function tests (CO diffusion capacity, flow volume relationships, vital capacity) were performed pre-treatment and at 3-month intervals post-transplant.
• Prophylaxis for graft-versus-host disease included methotrexate and/or cyclosporin A.

Main Results:

• Pre-treatment, patients showed significantly reduced CO diffusion capacity compared to predicted values.
• Flow volume relationships remained within normal limits before treatment.
• Following bone marrow transplantation, a further, irreversible decline in CO diffusion capacity and vital capacity was observed.
• These pulmonary function declines suggest an additive effect of lung irradiation.

Conclusions:

• Total body irradiation, a component of the conditioning regimen for allogeneic bone marrow transplantation, leads to irreversible pulmonary damage.
• Reduced CO diffusion capacity and vital capacity post-transplant indicate significant lung toxicity from TBI.
• Further research is needed to understand the pre-existing factors contributing to reduced CO diffusion capacity and to mitigate TBI-induced lung injury.