Talc is also a more attractive sclerosing agent when cost is analyzed. Review of our inpatient pharmacy charges for the currently available sclerosing agents showed bleomycin (60 U, $3,680) was 65 times as costly as talc (4 g, $56). Doxycycline (1,000 mg, $120) was more reasonably priced but still more than two times the talc expense.
As talc appears to be the most efficacious and cost-effective sclerosant, the remaining controversies center on the route of delivery. Most of the published experience with talc involves intraoperative insufflation of the agent as a fine powder. The operator can, at the same time, ensure all fluid has been drained, lyse any restricting adhesions, break up loculated collections, and visually confirm adequate disbursal of the talc. In contrast, Chambers in 1958 and Webb et al in 1992 demonstrated 85 to 100% effective control of MPE administering talc as a slurry through a chest tube at the patient’s bedside. They reported less treatment-associated pain and certainly could argue that costs are reduced by avoiding operative and anesthetic charges. To address just these issues, a prospective, randomized trial of operative talc poudrage vs bedside talc slurry sclerosis is underway within the cooperative cancer groups throughout North America. End points of this study include recurrence of MPE, quality-of-life analyses, and cost analyses. We anxiously await the results of this trial to finally establish a rigorously tested, economically sound standard for the treatment of patients with MPE.
Malignant Pericardial Effusions
Pericardial tamponade due to a malignant effusion accounts for at least half of all reported cases of pericardial fluid collections requiring intervention. Malignant pericardial effusions occur less frequently than MPEs; however, they often are acutely life threatening. The pathophysiologic condition usually involves metastasis to the parietal/ fibrous pericardium, although visceral or epicardial involvement with or without frank myocardial invasion is also seen. As with pleural effusive processes, preexisting mediastinal disease or prior radiotherapy may contribute to pericardial effusions because the lymphatic drainage necessary for pericardial fluid homeostasis has been obstructed. By whichever mechanism(s), the net fluid buildup inhibits passive diastolic filling of the normally low-pressure right heart structures, producing the classic physical signs of cervical and abdominal venous hypertension. The same pathophysiologic condition accounts for the diagnostic echocardiographic findings of right atrial and right ventricular diastolic collapse. As with MPE, carcinomas of the lung and breast, as well as lymphoma, comprise the most common oncologic etiologies. Autopsy studies show pericardial involvement by common malignancies in 1 to 20% of reported cases.