Predictive value of marker half-life in relapsed and nonrelapsed nonseminomatous germ cell testicular tumor patients undergoing chemotherapy

The aim of this study was to investigate the influence of a marker half-life (MHL) on relapse in nonseminomatous germ cell testicular tumor patients. MHL was retrospectively analyzed in relapsed (n = 37) and nonrelapsed patients (n = 28) undergoing first-line chemotherapy (CT). Before CT and after the second cycle of CT, serum α-fetoprotein (AFP) and β-human chorionic gonadotropin levels were measured for MHL analysis. The International Germ Cell Cancer Collaborative Group risk classification system was used to assess the correlation between MHL and relapse. MHL was calculated according to a logarithmic formula. Median follow-up was 25 months (range, 6 to 96 mo). A statistically significant difference was not observed between initial AFP (P = 0.266) and β-human chorionic gonadotropin (P=0.092) in both patient groups. MHL was statistically different between the relapsed and nonrelapsed patients with a good, intermediate, and poor prognosis, except for the half-life of AFP in patients with a poor prognosis. MHL is an indicator that predicted recurrence. Patients with an MHL longer than expected should be investigated to improve the effectiveness of treatment and should be treated with a recovery regimen.