An autopsy case of massive pulmonary tumor embolism due to undiagnosed prostatic adenocarcinoma.

Adenocarcinoma of the prostate is occasionally associated with pulmonary embolism, occurring as a result of secondary hypercoagulable states or cancer-associated emboli. The objective of this study was to provide a review of clinical, histopathological and immunohistochemical features of poorly differentiated prostatic adenocarcinoma, emphasizing the relevance of undiagnosed malignancy as a cause of pulmonary embolism. The current study describes the case of a 78-year-old male who experienced remarkable clinical symptoms suggestive of pulmonary embolism. Following several diagnostic examinations, the patient was diagnosed with pulmonary embolism, which led to the detection of prostatic adenocarcinoma. Poorly differentiated adenocarcinoma with a Gleason's score of nine was set as a definite diagnosis. Multiple tumor emboli within small and medium-sized pulmonary blood vessels were found in all specimens taken from lung tissue. Immunohistochemical analysis showed diffuse and strong positivity of tumor cells within pulmonary arteries. Hidden malignancy is a diagnostic challenge that should be considered in the differential diagnosis of pulmonary embolism. Laboratory and radiological findings with additional histopathological evaluation are needed for the definite diagnosis.