A clinical evaluation of the TK 210 ELISA in sera from breast cancer patients demonstrates high sensitivity and specificity in all stages of disease.

Thymidine kinase (TK1) is an enzyme involved in DNA synthesis that leaks into the blood as a result of high cell turnover, particularly in the case of cancer. Serum TK1 activity has been used for prognosis and monitoring of leukemia and lymphoma patients for many years. Here, we describe the first clinical results with the newly developed TK 210 ELISA from AroCell AB. Sera from 124 breast cancer patients with known TNM classification along with sera from 53 healthy females were analyzed by TK 210 ELISA for TK1 protein and TK1 activity levels by the 3[H]-deoxythymidine (dThd) phosphorylation assay. The limit of detection for the TK 210 ELISA was 0.17 ng/ml, and 60 % of the sera from female blood donors were below this value. The median TK1 levels found in sera from breast cancer patients with T1 to T4 stage disease were 0.31, 0.46, 0.47, and 0.55 ng/ml, and these levels significantly differed from healthy controls. The median values of the biomarker CA 15-3 were also increased in patient sera from T1 to T4 patients (16, 34, 36, 40 U/ml, respectively). TK 210 ELISA showed significantly higher sensitivity for the T1 and T2 breast cancer patients compared to the TK activity assay. The combination of the TK1 ELISA and CA 15-3 biomarkers demonstrated a significant increase in sensitivity up to 15 % compared to each marker alone. This evaluation of the TK 210 ELISA strongly suggests that it can provide independent and complementary information for patients with breast cancer.

Perspectives on digoxin absorption from small bowel resections.

Digoxin is a commonly prescribed medication for a variety of cardiovascular abnormalities. The therapeutic index of digoxin is considered narrow and drug is absorbed predominantly from the duodenum and upper jejunum. When the small intestine is intact, the absorption can vary; therefore, in the case of a small bowel resection or bypass, this erratic absorption may be accentuated. There is some controversy concerning the effect of small bowel resection or bypass on the absorption of digoxin. Some investigators have shown that small bowel resection or bypass decreases the absorption of oral digoxin, whereas others report no change in absorption. When the study methodologies were evaluated, certain common factors that support each view were found. In most studies reporting malabsorption, a solid dosage form of digoxin was used. Studies reporting no change in absorption investigated a solution dosage form.