Unusual Patterns of Thoracic Metastasis of Urinary Bladder Carcinoma

Urinary bladder carcinoma (UBC) is the ninth most common malignancy and the second most common urological malignancy after prostate cancer in men. Thoracic metastases occur in more than half of those with muscle-invasive disease, and these generally assume the form of multiple solid parenchymal lesions characteristic of hematogenous seeding of the lung. Unusual patterns of thoracic spread of UBC have also been described albeit sporadically in the form of case reports and series. The aim of our case series is to provide illustrations of several atypical patterns of thoracic involvement by UBC such as isolated mediastinal lymphadenopathy, cavitary lung metastases, malignant pleural effusion, endobronchial disease, and pulmonary tumor embolism. This review is meant to highlight the intersection of the fields of urological oncology and thoracic radiology in the care of patients with UBC.