[Exclusive demonstration of creatine phosphokinase BB isoenzyme in serum, pleural fluid and neoplastic tissue in a case of small-cell pulmonary neoplasm]

Abstract

The presence of circulating CPK BB isoenzyme is not as rare as was originally supposed. Theoretically damage of organes containing CPK activity should release soluble enzyme into the general circulation. So CPK BB has been reported in sera of patients with brain injury, prostate resection or with gastrointestinal malignant diseases. We present one case of small-cell lung carcinoma associated with 100% of CPK activity type BB in serum. This enzyme pattern was found also in malignant pleural effusion and in the biopsy of the malignant tumour tissue. In this tissue total CPK activity was found markedly more than in normal lung tissues or in epidermoid lung cancers. Brain type CPK is the fetal form of the enzyme and it is possible that our findings is yet another example of tumour expression of a fetal marker in the case of this very undifferentiated tumour.