Efficacy of the metastatic survey in the staging of gestational trophoblastic disease.

Between 1965 and 1987, 190 patients with nonmetastatic and 134 patients with metastatic gestational trophoblastic disease (GTD) underwent initial metastatic survey at the Southeastern Regional Trophoblastic Disease Center (Durham, NC). These patients were evaluated for characteristics which might predict the presence of high-risk metastases before a full radiographic survey was obtained. Minimal staging evaluation of all patients included history and examination, quantitative HCG level by beta-subunit radioimmunoassay, chest radiograph, and evaluation for brain and liver metastases with radionuclide or computed tomography (CT) scans. Seventeen patients had high-risk sites of metastases (i.e., those outside lungs, vagina, or pelvis). Characteristics were identified which might predict high-risk metastases: (1) all had metastases in lungs or vagina; (2) 13 of 17 (76%) had at least one other high risk factor (i.e., beta-HCG titer greater than 40,000 mIU/ml, greater than 4 months since onset of symptoms or antecedent term pregnancy; and (3) 15 of 17 (88%) had obvious symptoms or signs related to high-risk metastasis. The authors then evaluated these criteria to identify high-risk metastasis: (1) asymptomatic patients with GTD are screened for therapy with history and physical examination, HCG level, and chest radiograph or CT of the lungs; and (2) further radiographic imaging is used only for patients with signs or symptoms of high-risk metastases, identifiable lung or pelvic metastases, or other high-risk clinical factors. Using this criteria, patients with high-risk metastases were identified with sensitivity of 100% and specificity of 63%. Approximately 60% of patients did not require further radiographic evaluation.