Objective: The purpose of this study is to clarify the existing issues on the clinical diversity, natural history, and mode of disease progression of pulmonary lymphangioleiomyomatosis (LAM).
Methodology: Eleven patients with LAM were reviewed retrospectively with special reference to serial changes in pulmonary function and radiological findings during the course of their disease, treatment, and outcome. All patients were female with a mean age of 33.8 years at presentation and the observation period ranged from 2.1 to 20.8 years (mean 7.4 years).
Results: Four of six patients, treated with anti-hormone therapy, presented with exertional dyspnoea, marked airflow limitation (forced expiratory volume in 1 s/forced vital capacity, 23-38%), and severely impaired diffusing capacity (%DLCO, 21.4-36% of the predicted). The remaining two patients showed only a decreased diffusing capacity (70.6% and 59.4% of the predicted) which rapidly deteriorated with subsequent development of airflow limitation. Repeated chest computed tomographic (CT) examinations revealed increasing numbers of cysts with simultaneous loss of normal lung parenchyma in these two patients. In contrast, the five patients who received no anti-hormone therapy had no respiratory symptoms aside from pneumothorax at onset. Remarkable differences were noted, with pulmonary function being well maintained and slow progression of cystic changes on CT being observed in the latter group.
Conclusions: Diverse clinical courses observed in patients with pulmonary LAM can be well delineated and assessed by periodic examinations including pulmonary function tests and chest CT imaging. Anti-hormone therapy is not always necessary for a certain group of LAM patients and they appear to have a stable course and favourable outcomes without anti-hormone treatment.