Cytologic findings of lymphangioleiomyomatosis in pleural effusion: a case report.

BACKGROUND

Lymphangioleiomyomatosis (LAM) is a rare disease occurring almost exclusively in females of reproductive age. Patients usually present with insidious and progressive dyspnea. Episodes of hemoptysis, pneumothorax, and chylothorax may occur, and the patient progresses to eventual respiratory failure and death. The characteristic pathologic finding is proliferation of immature smooth muscle cells (LAM cells) in the lungs, lymphatics and lymph nodes of thorax and abdomen/ retroperitoneum.

CASE: A 47-year-old woman with a 1-year history of LAM diagnosed on iliac lymph node biopsy presented with progressive dyspnea and pleural effusion. A chest tube was placed. The collected pleural fluid, which represented chylothorax, yielded cohesive clusters of cells consisting of 2 cell populations: an outer, discontinuous layer of flattened cells and an inner portion of ovoid spindle cells. By immunohistochemistry the inner cells stained with smooth muscle actin and were negative for keratin.

CONCLUSION

The characteristic constellation of clinical findings and distinctive cytology in conjunction with immunohistochemistry staining can render the diagnosis of LAM in effusions.