Gestational Trophoblastic Tumours
TNM 7 Classification
TNM 6 Classification
1. Rules for ClassificationThe following classification for gestational trophoblastic tumours is based on that of FIGO adopted in 1992 and updated in 2001 (Gestational trophoblastic tumours. Ngan HYS, Odicino F, Maisonneuve P, Beller U, Benedet JL, Heintz APM, Pecorelli S, Sideri M, Creasman WT. J Epidemiol Biostatist 2001;6:175-184). The definitions of T and M categories correspond to the FIGO stages. Both systems are included for comparison. In contrast to other sites, an N (regional lymph node) classification does not apply to these tumours. A prognostic scoring index, which is based on factors other than the anatomic extent of the disease, is used to assign cases to high risk and low risk categories, and these categories are used in stage grouping.
The classification applies to choriocarcinoma (9100/3), invasive hydatidiform mole (9100/1), and placental site trophoblastic tumour (9104/1). Placental site tumours should be reported separately. Histological confirmation is not required if the human chorionic gonadotropin (hCG) level is abnormally elevated. History of prior chemotherapy for this disease should be noted.
The following are the procedures for assessing T and M categories:
T categories. Physical examination, imaging including urography and cystoscopy
M categories. Physical examination and imaging
Risk categories. Age, type of antecedent pregnancy, interval from index pregnancy, pretreatment hCG, diameter of largest tumour, site of metastasis, number of metastases, and antecedent treatment are integrated to provide a prognostic score that divides cases into low and high risk categories.
2.1. Primary Tumour
2.2. M - Distant Metastasis
MX. Metastasis cannot be assessed
M0. No distant metastasis
M1. Distant metastasis
M1a. Metastasis to lung(s)
M1b. Other distant metastasis
Note: Genital metastasis (vagina, ovary, broad ligament, fallopian tube) is classified T2. Any involvement of non-genital structures, whether by direct invasion or metastasis is described using the M classification.
3. pTM Pathological ClassificationThe pT and pM categories correspond to the T and M categories.
4. Prognostic Score
5. Stage Grouping