Malignant pleural effusion from squamous cell carcinoma of the vulva: extremely rare metastatic pattern of a rarely metastasizing cancer.

The discovery of a malignant pleural effusion indicates metastatic disease and thus invariably results in the highest possible cancer stage. Although the female reproductive tract overall is a common primary tumor site giving rise to malignant pleural effusion, vulvar carcinoma stands out for its propensity for locoregional spread rather than distant metastasis. Our case contributes to the extremely limited number of published descriptions of thoracic involvement by vulvar carcinoma, with malignant pleural effusion being a particularly unusual pattern.