Diagnostic Yield of Cytological Examination of Malignant Pleural Effusion in Different Breast Cancer Pathologies

The serous pleural cavity is an enclosed space covered by the parietal and visceral layers of serous membranes, which are lined by a monolayer of mesothelial cells supported on fibrous tissue rich in capillaries and lymphatic. Under physiological conditions, these two layers are in juxtaposition and only a small amount of fluid is Present inside these compartments, acting as a lubricant to avoid friction.

Many infectious, benign, and malignant diseases can cause pleural effusion. Approximately one-fourth of all pleural effusions and 30 - 70% of all exudative effusions in hospital settings are secondary to cancer.

Lung cancer is the most common metastatic tumor to the pleura in men, while breast cancer is the most common tumor in women.

Breast cancer is the most commonly diagnosed malignant tumor in women worldwide and the most common cause of malignancy- related deaths. Breast cancer patients constitute approximately 36% of all oncological patients. The incidence of breast cancer is gradually increasing worldwide.

Since breast cancer is a heterogeneous disease that varies from clinical course to molecular subtypes, it includes a wide spectrum of diseases with different presentations and morphological, biological, and clinical phenotypes. Therefore, the behavior and treatment success of breast cancer vary greatly from person to person, and, as a result, it is possible to encounter very different personalized prognosis processes in breast cancer patients.