Marker Half-Life Analysis as a Prognostic Tool in Testicular Cancer

Abstract

In a retrospective study the actual half-life (t1/2) of the serum tumor markers .alpha.-fetoprotein and human chorionic gonadotropin was compared to the clinical course of patients who underwent an operation or chemotherapy for germ cell cancer. Of the 7 patients with residual disease postoperatively, 5 had abnormal t1/2 values and in 3 this knowledge would have been of clinical value. Only 1 of 10 patients with a complete response to chemotherapy had an unfavorable actual t1/2 compared to 17 of 19 with a less than complete response. Prolonged marker decay rates during the first month of chemotherapy reflected ineffective chemotherapy and appeared to be independent of tumor bulk. Postoperatively, actual t1/2 probably are useful prognostically only if the values are abnormal. Similar calculations may be of prognostic value early in the course of induction chemotherapy.