Elevated CK-MB and CK-BB in serum and tumor homogenate of a patient with lung cancer.
Elevated serum levels of creatine kinase (CK) were found in a patient with small-(oat) cell carcinoma of the lung. Fractionation of the enzyme showed markedly elevated CK-MB and CK-BB isoenzymes. Clinical and subsequent pathological examination showed no evidence of infarction, inflammation, or tumor involvement of the heart; however, analysis of tumor tissue for CK showed predominance of CK-MB and CK-BB isoenzymes, thus implicating tumor as the source of the circulating levels of CK-MB and CK-BB. Our case is the first to document CK-MB from neoplastic tissue homogenates, and illustrates that markedly elevated circulating levels of CK-MB, or increased levels of CK-MB in combination with CK-BB may point away from a myocardial source, and toward the existence of a malignancy.
Lee
B I
BI
Bach
P M
PM
Horton
J D
JD
Hickey
T M
TM
Davis
W A
WA
D000368:Aged; D018288:Carcinoma, Small Cell / Q000201:enzymology*; D003402:Creatine Kinase / Q000097:blood*; D003937:Diagnosis, Differential; D006801:Humans; D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008168:Lung / Q000201:enzymology; D008175:Lung Neoplasms / Q000201:enzymology*; D008297:Male; D009132:Muscles / Q000201:enzymology; D009203:Myocardial Infarction / Q000201:enzymology; D009206:Myocardium / Q000201:enzymology
D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase; D003402:Creatine Kinase