In order to determine the diagnostic and prognostic significance of low pleural glucose and pH levels, we executed a prospective study of these parameters and cytologic yield in 77 cases of malignant pleural effusions diagnosed from 116 consecutive thoracoscopies. The extension of the neoplasms detected by thoracoscopy as well as the results of our attempts to carry out pleurodesis by talc were also studied. Pleural glucose levels were less than 60 mg/dl in 16 cases, and the cytologic yield was positive in 14 of these cases (87%). The glucose value rose above this level in 61 cases, and the cytology was positive in 30 cases (49%; p less than 0.006). A pH less than 7.30 was encountered in 18 cases and there were positive cytologic findings in 14 of these cases (78%). The pH was above 7.30 in 46 cases, and cytologic studies were positive in 22 cases (48%; p less than 0.03). There were ten cases in which both the glucose and pH levels were low, and the cytology was positive in 9 cases (90%), while there were 40 cases in which both the glucose and pH levels were high and cytologic yields of 20 of these cases were positive (50%; p less than 0.03). The extension of the lesions observed during thoracoscopy showed important differences as far as this related to the glucose levels (p less than 0.005), but this relationship as it concerned pH levels was even more significant (p less than 0.0002). The differences were also highly significant (p less than 0.003) when the glucose and pH were jointly considered.(ABSTRACT TRUNCATED AT 250 WORDS)
We examined the post-mortem records of 191 patients who had one or more malignant tumours (196 neoplasms in total). We found 55 cases with pleural metastases (28%) and 30 of these presented pleural effusions (15% of the total number of neoplasms). The visceral pleural was involved in all 24 cases of lung cancer with pleural metastasis and in 27 out of 31 of those of other origins. The parietal pleura was affected in 16 out of 24 cases of the lung tumours and in 15 out of 31 of those of other origins. There were no cases in which only the parietal layer of the pleura was involved, with the only exception of neighbouring tumours. We found neoplastic vascular invasion in 43 out of 55 cases, retrograde lymphatic spread from the mediastinum in two cases, and direct pleural involvement from a neighbouring tumour in the remaining. We conclude that malignant pleural implantation fundamentally arises from the spread of tumour emboli to the lungs and the visceral pleura, with secondary seedings to the parietal pleura. Therefore, this phenomenon leads to the usual finding of lower involvement of parietal pleura as compared to the visceral pleura in our series.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.