Pulmonary abnormalities at long-term follow-up of patients with Langerhanscell histiocytosis

Background. In Langerhans cell histiocytosis (LCH) pulmonary involvement, w hich is often initially asymptomatic, may contribute to significant morbidi ty and mortality. To determine the long-term prognosis, a cross-sectional s tudy was undertaken. Procedure. Forty-one patients with greater than or equ al to 5 years follow-up after the diagnosis of LCH were interviewed and und erwent physical examination, blood tests, a chest X-ray and a high-resoluti on CT (HRCT) of the lungs. All patients included had been referred to the D epartment of Pediatrics at the Karolinska Hospital in Stockholm between Jul y 1962 and February 1990 (median follow-up 16 years). Biopsies from all pat ients were reviewed and confirmed to be consistent with LCH. Information on previous clinical features including treatment and the results of chest X- rays were also collected for risk factor analysis. Results. Radiographic ab normalities of the lungs (cysts and/or emphysema), found in 10/41 (24%) at follow-up, were classified into five groups according to the extent of the cysts. These patients had more often suffered from multisystem than from si ngle-system disease (P = 0.01), were significantly older at diagnosis (P < 0.001), and had been more heavily treated with chemotherapy and/or radiothe rapy. They were also more frequently smokers (P < 0.0001) and 7/10 (70%) ha d suffered lung involvement at diagnosis. At the time of diagnosis of the p ulmonary involvement, 4/10 (40%) patients had respiratory symptoms, but onl y 2/10 (20%) had symptoms at follow-up. Conclusions, Ten (24%) of the 41 pa tients had abnormal findings on radiological examination of the lungs at lo ngterm follow-up and seven are or had been smokers. It is of great importan ce that patients with LCH be informed about smoking-related pulmonary morbi dity. Prolonged monitoring of the lungs for smokers and patients with known pulmonary involvement is recommended. Med. Pediatr. Oncol. 36:459-468, 200 1. (C) 2001 Wiley-Liss, Inc.