Single-center retrospective analysis of hCG and AFP time-points from 65 patients with IGCCCG intermediate-poor risk NSGCT treated with 4 cycles of bleomycin-etoposide-cisplatin (BEP). To determine AUChCG and AUCAFP for D0-D42, AUCs for D0-D7 were calculated using the trapezoid rule and AUCs for D7-D42 were calculated using the mathematic integrals of equations modeled with NONMEM. Combining AUCAFP and AUChCG enabled us to define 2 predictive groups: namely, patients with favorable and unfavorable AUCAFP-hCG. Survival analyses and ROC curves assessed the predictive values of AUCAFP-hCG groups regarding progression-free survival (PFS) and compared them with those of half-life (HL) and time-to-normalization (TTN).
Mono-exponential models best fit the patterns of marker decreases. Patients with a favorable AUCAFP-hCG had a significantly better PFS (100 % vs 71.5 % , P = .014). ROC curves confirmed the encouraging predictive accuracy of AUCAFP-hCG against HL or TTN regarding progression risk (ROC AUCs = 79.6 vs 71.9 and 70.2 respectively). Because of the large number of patients with missing data, multivariate analysis could not be performed.
AUCAFP-hCG is a dynamic parameter characterizing tumor marker decline in patients with NSGCT during BEP treatment. Its value as a promising predictive factor should be validated.