Postmortem Diagnosis of Gallbladder Cancer Presenting as Pulmonary Lymphangitic Carcinomatosis With Concurrent Gallbladder Adenomyomatosis.

In pulmonary lymphangitic carcinomatosis, it can be difficult to identify the primary site of the cancer on computed tomography (CT) imaging. Here, we report a rare case of pulmonary lymphangitic carcinomatosis, which was difficult to diagnose as gallbladder cancer. An 81-year-old woman, previously followed up for gallbladder adenomyomatosis, presented with persistent cough. CT revealed multiple small nodular opacities, irregular interlobular septal thickening, and bilateral pleural effusions. Based on the CT findings and the presence of malignant cells in the pleural fluid, a presumptive diagnosis of pulmonary lymphangitic carcinomatosis was made, but the primary site was not identified. The patient died of respiratory failure in two months. Autopsy confirmed gallbladder cancer with pulmonary lymphangitic carcinomatosis and multiorgan metastasis. Clinicians should be aware that in patients with gallbladder adenomyomatosis, gallbladder cancer can present with rapidly progressive respiratory symptoms even in the absence of an evident mass or increased gallbladder wall thickening.