Which of the following is a risk factor for the develoment of Choriocarcinoma?

Poor-prognosis patients, based on the Clinical Classification of Malignant Disease, are those with any of the following risk factors: *Serum b-hCG titers greater than 40,000 mlU/mL at the onset of treatment *Diagnosis of disease more than 4 months after molar pregnancy *Brain or liver metastases *Prior unsuccessful chemotherapy *Onset following term gestation.