Clinical Features And Natural History Research Tube Fibroid Disease (LAM) Of Lymph

Background:Lymphangioleiomyomatosis(LAM) is a rare disease that occurs almost exclusively in women, and its low disease prevalence hinders research on large patient registries. So far, only a few studies described Asian LAM patients, and among them there was no registry study carried out on Chinese patient population.Objectives:To characterize and estimate the clinical features and natural history of LAM in Chinese population. Also, to further testify the diagnostic efficacy of serum vascular endothelial growth factor-D (VEGF-D) as a biomarker, as well as its correlation with clinical manifestations.Methods:Among LAM patients registered in Peking Union Medical College Hospital, we selected121who fits study criteria for medical data collection and telephone follow-up. We constructed a LAM patient database for data storage and analysis. We also collected serum samples from97of the121patients to determine their serum VEGF-D levels by ELISA.Results:Among121LAM patients in our study,83were diagnosed with definite sporadic LAM (D S-LAM),34probable LAM (PRO-LAM), and4tuberous sclerosis complex-LAM (TSC-LAM).1) Demographics:the age of disease onset in patients with sporadic LAM ranged between30-40years old.2) Clinical manifestations: The most common initial symptoms for LAM were dyspnea on exertion and spontaneous pneumothorax. Patients with at least one episode of pneumothorax tended to have earlier onset of disease compared with patients who never had any pneumothorax. Among patients who underwent echocardiogram study,25.3%had documented pulmonary arterial hypertension.3) Baseline evaluations:at baseline,23.6%patients had normal spirometry test results.66.3%showed obstructive patterns, while only a few patients presented with restrictive patterns. Hyperinflation was observed in about one-fifth of patients.91.9%patients showed low diffusing capacities.12%patients had documented hypoxemia.4) FEV1declining rate in patients not on rapamycin: there were64patients with data to analysis. The mean decline of FEV, was132ml/year. For the38D S-LAM patients, mean decline of FEV, was72ml/year.5) Serum VEGF-D level correlated with lymphatic disease, as well as arterial blood gas analysis results, but failed to show similar correlation with pulmonary function test results.6) Of the121patients, we were able to follow up with109, lost follow-up in9.9%patient. Total8patients died. Estimated5-year survival rate was95.6%,10-year survival rate was87.9%.Conclusions:LAM is mainly seen in Chinese women of reproductive age. Compared with US and Europe patient registries, Chinese patients showed worse baseline pulmonary function test results, and higher percentage of documented pulmonary arterial hypertension. The long-term survival rate is similar. LAM patients show remarkable heterogeneity in terms of clinical complications and rate of disease progression, and these may be correlated and even predicted by the age of disease onset and results of pulmonary function test and arterial blood gas analysis at baseline evaluation. However, larger registry studies are required to validify these conclusions.