Gestational trophoblastic disease. The effect of duration of disease and hCG titer on response to therapy.

The height of the pretreatment hCG titer and the time interval from termination of the antecedent pregnancy to institution of treatment were determined in 352 patients with gestational trophoblastic disease in order to judge their effect, both individually and together, on response to therapy. When all patients in need of treatment for gestational trophoblastic disease, both metastatic and nonmetastatic, were considered as one group, examination of time alone, of hCG titer alone and of time and titer together each permitted the identification of patients at high risk with equal reliability (p less than 0.0005 for each). When patients with only metastatic gestational trophoblastic disease were evaluated, time and titer taken separately and together each identified those patients at high risk, but not in an equal manner (time alone, p = 0.02; titer alone, p less than 0.05; time and titer together, p less than 0.0005). Time and hCG titer, alone or in combination, did not have a statistically significant effect on outcome when patients with metastatic choriocarcinoma were considered separately. Other factors, such as metastatic site and antecedent pregnancy, seem to be more important in determining prognosis than duration of disease and hCG titer in this group of patients.