Gestational Trophoblastic Tumor Staging 

Updated: Dec 31, 2015
  • Author: from Memorial Sloan-Kettering - Elizabeth L Jewell, MD, MHSc; Chief Editor: from Memorial Sloan-Kettering - Yukio Sonoda, MD  more...
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Staging and Scoring for Gestational Trophoblastic Neoplasia

Gestational trophoblastic neoplasia (GTN) is staged by The American Joint Committee on Cancer (AJCC) and the Féderation Internationale de Gynécologie et d’Obstétrique (FIGO) based on the criteria below (see table 1). [1, 2] The FIGO staging and classification system is more commonly used, since lymph nodes are rarely evaluated in the staging of GTN.

Table 1. TNM Classification for Gestational Trophoblastic Neoplasia [1] (Open Table in a new window)

Primary tumor (T)

TNM category

FIGO stage

Surgical-pathologic findings

TX

 

Primary tumor cannot be assessed

T0

 

No evidence of primary tumor

T1

I

Tumor confined to uterus

T2

II

Tumor extends to other genital structures (ovary, tube, vagina, broad ligaments) by metastasis or direct extension

Distant metastasis (M)

TNM category

FIGO stage

Surgical-pathologic findings

M0

 

No distant metastasis

M1

 

Distant metastasis

M1a

III

GTN extends to the lungs with or without known genital metastases

M1b

IV

All other metastases

The World Health Organization (WHO) prognostic scoring system is important in the medical management of patients with complete hydatidiform moles, partial hydatidiform moles, and choriocarcinomas. [2] Therefore, the FIGO staging system incorporates a modified WHO prognostic scoring system.

The scores from the 8 risk factors are summed and incorporated into the FIGO stage, separated by a colon (eg, stage II:4, Stage IV:9). Scores of 0-6 are considered low risk. Scores of 7 and greater are considered high risk (see Table 2, below). [2] The modified WHO prognostic scoring system is not applicable to patients with placental-site trophoblastic disease (PSTT) or epithelioid trophoblastic tumor (ETT).

Table 2. Modified WHO Prognostic Scoring System as Adapted by FIGO [2] (Open Table in a new window)

Risk factor

Score of 0

Score of 1

Score of 2

Score of 4

Age

< 40y

≥40y

Antecedent pregnancy

Mole

Abortion

Term

Interval months from index pregnancy

< 4

4-6

7-12

>12

Pretreatment serum hCG* level

< 103

103 -104

104 -105

>105

Largest tumor size (including uterus)

< 3 cm

3-4 cm

≥5 cm

Site of metastases

Lung

Spleen, kidney

Gastrointestinal system

Liver, brain

Number of metastases

1-4

5-8

>8

Previous failed chemotherapy

Single drug

≥2 drugs

*hCG = human chorionic gonadotropin