Staging and risk classification of gestational trophoblastic disease (GTD)

Four different staging classification systems for malignant gestational trophoblastic disease (GTD) have been used, including the Hammond Clinical Classification, FIGO, WHO, and the Charing Cross. In an attempt to unify these 4 major staging systems, the new FIGO 2000 staging/scoring system has been developed combining the basic FIGO anatomic staging with the modified WHO risk factor scoring system.

FIGO 2000 staging/scoring system

The FIGO 2000 staging/scoring system of GTD combines the anatomic FIGO staging of GTD (table 1) with the modified World Health Organisation risk factor scoring system.^r

Table 1: Anatomic FIGO staging of GTD

Table 2: FIGO 2000 staging/scoring system of GTD

In order to implement the FIGO 2000 staging/scoring system the following criteria for diagnosis need to be accepted.^r

Trophoblastic neoplasia after hydatidiform mole evacuation

• 4 values or more of plateau of hCG over at least 3 weeks; days 1, 7, 14 and 21.
• Rise of hCG of 10% or greater for 3-values or longer over at least 2 weeks; days 1, 7 and 14.
• Persistence of hCG 6 months after mole evacuation.
• Presence of histologic choriocarcinoma.

Metastases

• Lung - CXR is adequate and CT scan is acceptable. CXR is used to count the number of metastases for risk score assessment.
• Intra-abdominal - CT scanning is preferred although many institutions may still use ultrasound for liver metastases.
• Brain - CT or MRI (preferred).

Risk groups

• Low-risk group - score less than or equal to 6.
• High-risk group - score greater than or equal to 7.