Circulating osteocalcin (BGP), the major noncollagenous bone protein, is elevated in patients with certain metabolic bone disease while its behavior in cancer patients, particularly those with bone metastases, is unclear. We measured circulating BGP in 37 healthy females, in 13 female patients with benign breast disease, and in a group of 51 cancer patients (breast, lung, prostate, and bladder) with and without bone metastases, before and after 4'-epidoxorubicin (4'-Epidx) therapy (4'-Epidx 120 mg/m2 every 3 weeks). Under basal conditions, mean BGP levels of all of these subjects fell within the normal range of 2.0-5.0 ng/ml (mean +/- SD, 4.8 +/- 1.0 ng/ml). In cancer patients without bone metastases BGP levels measured before and after 4'-Epidx therapy were not significantly different (4.4 versus 4.6 ng/ml). Only in breast cancer patients with multiple bone metastases was circulating BGP higher after the onset of antiblastic treatment and through the entire course of therapy, accompanied by bone pain remission and regression of bone lesions (BGP = 6.7 +/- 1.3 ng/ml). Thus an increase in BGP concentration can be considered as a biological marker of recovered osteoblast activity during therapeutically induced stabilization or regression of skeletal metastatic lesions.

We investigated the diagnostic role of creatine kinase isoenzyme BB (CK-BB) in lung cancer. CK-BB was assayed using a radioimmunological system by saturation with Mallinchrodt double antibody 125I labelled (RIA Quant-CPK-BB). Sensitivity was 97% and specificity 90% in 44 cancers (T2-T3), in 36 non-cancers (chronic bronchitis) and in 48 healthy controls. Mean serum CK-BB values for patients with chronic bronchitis (2.64 ± 1.1 ng/ml) were virtually the same as in normal subjects. Patients with lung cancer had markedly higher serum CK-BB values (9.17 ± 2.6 ng/ml) than either the control group (healthy subjects) or the chronic bronchitis patients (p < 0.01). These results lead us to suggest that CK-BB serum determination might prove useful in screening pulmonary disorders. However, further studies are essential to establish: 1) the relationship between serum levels of the isoenzyme and the histology and stage of the neoplastic disease; 2) the relation between CK-BB and the aggressive potential of the neoplastic clone.

Sixteen female patients underwent signal-averaged electrocardiography and radionuclide angiography for the assessment of the resting left ventricular ejection fraction in the course of chemotherapy with mitoxantrone (MTX) for advanced breast cancer. Nine patients had received prior cardiotoxic treatments. Our findings indicate that patients treated with MTX may develop late potentials.