We investigated the long-term pulmonary sequelae of 38 children surviving 3 to 11.5 years (median 7 years) after high-dose chemotherapy (HDC) and autologous bone marrow transplantation (ABMT) without TBI. This cross-sectional study included patients with neuroblastoma (21), non-Hodgkin's lymphoma (7), Ewing's sarcoma (5), rhabdomyosarcoma (3), medulloblastoma (1) and ALL (1). They were asked and examined for clinical signs and underwent a physical examination with chest X-ray; 33/38 had pulmonary function tests (PFT) performed. No obstructive disease was found. Fifteen out of 32 evaluable PFT (47%) were abnormal with a pulmonary restrictive syndrome in 10, and borderline values in five patients. Four of these 15 patients were symptomatic with exertional dyspnea and two of four had abnormal chest X-rays. The etiology was mainly multifactorial, associating HDC with thoracic radiotherapy +/- scoliosis/kyphosis +/- previous thoracotomy +/- post-ABMT interstitial pneumonitis. Only 3/10 patients with a restrictive syndrome had HDC containing BCNU or busulfan as the only risk factor for lung disease. We conclude that the prevalence of late pulmonary sequelae after ABMT without TBI is moderate and rarely due to HDC alone, since most abnormal PFT can be explained by heavy pretreatment prior to ABMT. As symptoms are scarce even in advanced disease, repeated testing and very long-term follow-up are needed.