Treatment of malignant pleural effusions with intracavitary Corynebacterium parvum.

Fifty-three cases of metastatic pleural effusion (30 haemorragic and 23 serofibrinous) were treated with 4 mg of Corynebacterium parvum (CP) injected weekly into the pleural cavity after total thoracentesis. Of the 53 effusions, 24 were metastases from lung cancer and 29 from breast cancer. Complete response (CR) was assessed as total resolution of pleural effusion after explorative thoracentesis. The results were as follows: 15 CR after two injections of CP, 30 CR after three, and 5 CR after the fourth administration. Three of 53 cases could not be evaluated because of early death. Of the 30 clearly haemorragic effusions, 25 turned into serofibrinosis after the first intrapleural injection of CP and the other five after the second. These findings indicate that intracavitary CP is the most adequate treatment for the control of neoplastic pleural effusion because it induces a significant clinical improvement with milder side effects with respect to other drugs and/or physical agents commonly used.