A rare case of pulmonary benign metastasising leiomyomatosis in a woman with a previous history of hysterectomy for uterine fibroids.

Benign metastasising leiomyomatosis (BML) is a rare disease, predominantly seen in premenopausal women. It poses a diagnostic dilemma and can be misdiagnosed as malignancy. Here we present a case of 41-year-old woman with a previous history of hysterectomy 10 years ago for multiple fibroids. She presented with shortness of breath and chest discomfort. Chest X-ray showed pulmonary infiltrates. She was diagnosed with sarcoidosis and treated with steroids without any improvement. Further investigations including CT scan and bronchoscopy and lavage failed to confirm a diagnosis. Subsequently she underwent video-assisted thoracoscopic surgery and histopathology revealed leiomyomatosis (so-called leiomyomatous hamartomas/benign metastasising leiomyomatosis). Oestrogen and progesterone receptors showed diffuse and strong nuclear staining. The patient was commenced on tamoxifen and a repeat chest X-ray in 8 weeks showed significant improvement. In women of reproductive age with previous hysterectomy and multiple lung nodules on imaging, the diagnosis of BML should be taken into consideration.