Spindle cell lesion on fine needle aspiration as an initial step for diagnosis of lymphangioleiomyomatosis: Report of a rare case.

Lymphangioleiomyomatosis (LAM) is a rare systemic disease of women of reproductive age characterized by proliferation of abnormal smooth muscle like cells (LAM cells). Patients with LAM characteristically present with chronic dyspnea and cough and less commonly with spontaneous pneumothorax. Manifestation of extrapulmonary LAM as an initial presenting symptom is rare with a renal angiomyolipoma and lymphangioleiomyoma being most common. Although histologic findings of LAM are well-described, the cytological features; however, have been described only in few case reports, which focus on pulmonary LAM. Here, we report a case where initial diagnosis of LAM was made on pelvic "lymph node" fine needle aspiration (FNA) and biopsy in otherwise asymptomatic 25-year-old female, leading to further investigation and detection of developing cystic lung lesions. FNA cytology from the pelvic "lymph node" yielded proliferation of spindle cells without cytologic atypia. This case presented both clinical and histopathologic challenge, requiring clinical correlation and immunohistochemical staining for diagnosis. While rare, it is important to consider LAM in the differential diagnosis of spindle cell lesions in aspirate from nodules around vascular bundles in women of reproductive age even without history of lung lesion.