Pleural Effusion after Diagnosis of Breast Cancer and Pseudomyxoma Peritonei

Li Liu, MD
Last Modified: November 1, 2001

My wife has a history of breast cancer with left mastectomy in 1996 and diagnosis of pseudomyxoma peritonei in 1997. She now has right pleural effusion. Have you ever heard of the pseudomyxoma peritonei becoming more aggressive and growing outside of the peritoneum?
Thanks,
F.

Li Liu, MD, OncoLink Editorial Assistant, responds:

Dear F,
Thank you for your interest and question.

The differential diagnosis of pleural effusion (fluid build up in the chest but outside the lung) is very wide. Normally the pleural fluid is formed primarily from the parietal pleura (which covers the surface of the chest wall diaphragm and mediastinum) and re-absorbed into lymphatics and visceral pleura capillaries (which covers lung surface). Any alterations of this formation-reabsorption mechanism will result in the accumulation of pleural fluid. An increase in water forces (seen, for example, in congestive heart failure) or decreases in suctioning forces (seen, for example, in low serum albumine level) in the microvascular circulation result in "transudates". Increased leakage of the microvascular circulation (seen, for example, in pneumonia) or impaired lymphatic drainage from the pleural space (such as in malignancies) results in "exudates". Fluid accumulating in the abdomen (ascites) can also move into the chest cavity causing pleural effusion.

Pseudomyxoma peritonei is an unusual condition in which gelatinous fluid collections are associated with mucinous implants on the peritoneal surfaces and omentum. Pseudomyxoma can occur in the pleural cavity presenting as pleural effusion, either as a primary disease or metastasis from pseudomyxoma peritonei (Thorax. 1993 Jan;48(1):94-5; Dis Colon Rectum. 1999 Jan;42(1):113-5). Breast cancer can also spread to the pleural surface and/or obstruct lymphatic drainage and cause pleural effusion.

Your wife should see her oncologists and have a complete work up to determine the cause of her pleural effusion. Thoracentesis (draining fluid from chest) with a thorough pleural fluid analysis and radiologic examinations sometimes may provide useful information.