DISTRIBUTION OF TC-99M COLLOID IN THE THORACIC CAVITY OF PATIENTS WITH MALIGNANT PLEURAL EFFUSIONS

The distribution of labelled tetracycline in the pleural space of pati ents with malignant effusions has been shown not to improve significan tly after rotating the patient. As the number of patients was small, w e investigated the distribution of an inert radio labelled colloid (Tc -99m) in the pleural space directly after administration and after 1 h of rotation. Nineteen examinations were performed in 18 patients with malignant pleural effusions. In two out of 19 examinations (11%) a co nsiderable improvement in distribution was observed and some improveme nt was found in five out of 19 examinations (26%). The relation betwee n distribution and the effect of tetracycline pleurodesis at 12 weeks and the identification of patients for whom pleurodesis would not be s uccessful were also studied. The analysis of the distribution and outc ome of pleurodesis was hampered by the fact that additional anti tumou r treatments were given after pleurodesis. Conclusions: The influence of rotation on the distribution of Tc-99m-colloid in the pleural space is minimal and indicates that this could be omitted. A distribution p attern predictive of failure of pleurodesis could not be identified in this study. (C) 1997 Elsevier Science Ireland Ltd.