Serum tetranectin (Se-TN) and CA-125 were measured in serum samples obtained before primary surgery, before start of chemotherapy and monthly during chemotherapy in 8 patients with ovarian cancer. The median Se-TN level before chemotherapy (7.3 mg/l) increased significantly after the start of chemotherapy (13.7 mg/l), with the highest increase for one survivor (145%). Five patients who died of cancer in the study period, had pronounced decreases (30-50%) in Se-TN with a maximal concentration during chemotherapy to the lowest concentration in the last sample. One patient who died 10 months after closure of the study had continuously normal Se-TN values, but the last CA-125 value elevated. The lead time could be calculated in four patients for Se-TN and six patients for CA-125. Median lead times of 3.6 months and 3.8 months were found for Se-TN and CA-125 respectively. In conclusion, chemotherapy induces significant increases in Se-TN levels. A decrease in Se-TN during chemotherapy is highly suspect for recurrence and a poor outcome. Measurements of TN should therefore be included in other comparative studies.