Lymphangitic pulmonary metastases in castrate-resistant prostate adenocarcinoma

Initial diagnosis and successful treatment of pulmonary tumor embolism manifesting as the first clinical sign of prostatic adenocarcinoma

Although pulmonary tumor embolism (PTE) is a well-recognized end-stage form of pulmonary metastases at postmortem examination, the entity is rarely the first clinical sign of prostate cancer. Diagnosis of this condition in patients who have no previous history of malignancy is a challenge. Herein, we reported a 79-year-old man presented with progressive, unexplained dyspnea on exertion. Microscopic PTE coinciding with pulmonary lymphangitic carcinomatosis were readily recognized based on the presence of multifocal dilatation and beading of the peripheral pulmonary arteries with thickening of the bronchial walls and interlobular septa on the initial thin-section chest CT images. Pathologic examination of the transbronchial lung biopsy specimen revealed tumor emboli occluding both the small muscular pulmonary arteries and lymphatic vessels. These tumor cells were positive for prostatic specific antigen on immunohistochemical staining. The final diagnosis of prostatic adenocarcinoma was confirmed. Remarkable clinical and radiographic improvement was achieved following bilateral orchiectomies and anti-androgen treatment.

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Pulmonary tumor embolism (PTE) can be the first clinical sign of advanced prostatic adenocarcinoma.

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CT findings of dilated, beaded peripheral pulmonary arteries should raise a concern of microscopic PTE.

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Dilated, beaded pulmonary arteries should not be mistaken for tree-in-bud opacities caused by bronchiolar disease on CT.

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Prostate cancer should always be considered in the differential diagnosis of adenocarcinoma of unknown origin in men.