Metastatic Pleural Malignancy Beyond Simplicity: A Case Report and Literature Review

Abstract

Pathologic involvement of the pleura presenting with pleural effusion is most often a secondary complication of some underlying diseases such as bacterial infection and neoplasm. Concerning neoplasm, it can be either a primary neoplasm: mesothelioma or a metastatic neoplasm. Secondary metastatic involvement is far more common than primary tumours. The most frequent metastatic malignancies arise from primary neoplasms of the lung and breast. In addition, malignancy from any organ of the body may spread to the pleural spaces such as ovarian carcinomas and metastatic lesions from the gastrointestinal tract, commonly cancer of the colon. In most metastatic involvements, a serous or serosanguineous effusion follows, that often contains neoplastic cells. For this reason, careful cytologic examination of the sediment is of considerable diagnostic value. It is also necessary to take pleural biopsy tissue together with diagnostic aspiration of pleural fluid for exclusion and confirmation of the most possible primary focus. Hence, the role of pathologist is a critical necessity in supporting appropriate clinical management of the patient. A case report and literature review is presented in this article, highlighting the value of immunohistochemistry and cytopathology in reaching to the final diagnosis.