Japanese trial for classification of gestational trophoblastic disease.

OBJECTIVE: To evaluate the clinical usefulness of the Japanese Diagnostic Score to differentiate choriocarcinoma clinically without histologic findings from persistent gestational trophoblastic disease (GTD).

STUDY DESIGN: We reviewed the clinical records and histologic reports on all 809 patients with persistent GTD treated with surgery and chemotherapy in Japan. There were 347 cases of choriocarcinoma and 462 cases of invasive mole with histologic confirmation. We retrospectively applied the Japanese Diagnostic Score to all patients for detection of choriocarcinoma in persistent trophoblastic disease.

RESULTS: The sensitivity of the score for choriocarcinoma was 92.2%. The specificity was 93.5%. This retrospective study showed that the accuracy of this scoring system to differentiate true malignant choriocarcinoma clinically from both low risk and high risk gestational trophoblastic neoplasia without histologic findings was 92.9%.

CONCLUSION: Our trial to differentiate choriocarcinoma clinically from persistent GTD without histologic findings using a unique scoring system was successful. Proper management in the early stages strongly influences the outcome of these diseases. This scoring system should be very useful in comparing the incidence and survival rate of choriocarcinoma between nations.