Clinical presentation and prognostic analysis of adult patients with Langerhans cell histiocytosis with pulmonary involvement.
BACKGROUND
The study aimed to investigate the clinical features and prognosis factors of adult patients with Langerhans cell histiocytosis (LCH) with pulmonary involvement, especially multisystem (MS) LCH with pulmonary involvement.


METHODS
We retrospectively analyzed the demographic materials, clinical features and treatment outcomes of 119 adult LCH patients with pulmonary involvement at our center from January 1990 to November 2019.


RESULTS
Among 119 patients, 13 (10.9%) had single-system (SS) LCH, and 106 (89.1%) had MS-LCH with pulmonary involvement. SS-LCH patients had higher smoking rate (84.6% vs 52.8%, P = 0.026) and smoking index (300 vs 200, P = 0.019) than MS-LCH patients. The percentage of respiratory symptoms of SS-LCH patients was higher than MS-LCH patients (84.6% vs 53.8%, P = 0.034). Pulmonary function was impaired in 83.8% of the patients, and DLCO was the parameter most frequently impaired, accounting for 81.1%. The median DLCO was 65.1% predicted. Patients with pneumothorax had significantly worse DLCO (P = 0.022), FEV1 (P = 0.000) and FEV1/FVC (P = 0.000) than those without pneumothorax. During the follow-up, 72.4% of the patients had stable pulmonary function, and 13.8% showed improvements after chemotherapy. The estimated 3-year OS and EFS were 89.7 and 58.3%, respectively. Patients with a baseline FEV1 ≤ 55% predicted had worse OS. A history of pneumothorax indicated worse EFS and cytarabine based therapy predicted better EFS.


CONCLUSIONS
An FEV1 ≤ 55% predicted and a history of pneumothorax at diagnosis indicated a poor prognosis. Cytarabine based regimen may arrest the decline in pulmonary function in LCH patients with pulmonary involvement and improve EFS.
['Miao|Hui-Lei|HL|', 'Zhao|Ai-Lin|AL|', 'Duan|Ming-Hui|MH|', 'Zhou|Dao-Bin|DB|', 'Cao|Xin-Xin|XX|https://orcid.org/0000-0001-7884-3073', 'Li|Jian|J|https://orcid.org/0000-0002-4549-0694']
D000293:Adolescent D000328:Adult D005260:Female D006646:Histiocytosis, Langerhans-Cell D006801:Humans D008175:Lung Neoplasms D008297:Male D008875:Middle Aged D011379:Prognosis D012189:Retrospective Studies D016019:Survival Analysis D055815:Young Adult
Adult Langerhans cell histiocytosis Pulmonary involvement Pulmonary function