Gestational trophoblastic diseases - clinical guidelines for diagnosis, treatment, follow-up, and counselling.

Hydatidiform mole is treated with surgical uterine evacuation with suction and blunt curettage (D). Medical uterine evacuation should not be used (C). On clinical suspicion of hydatidiform mole, one representative sample of the evacuated tissue is fixed for histopathologic investigation and one is forwarded unfixed for genetic analysis (D). Serum hCG is measured on suspicion of hydatidiform mole. At the time of the uterine evacuation, the initial hCG is measured (A). After a hydatidiform mole that is both triploid and partial, serum hCG is measured weekly until there are two consecutive undetectable values (< 1 or < 2), after which the patient can be discharged from follow-up (C). After a diploid hydatidiform mole, a complete mole, or a hydatidiform mole without valid ploidy determination, serum hCG is measured weekly until the value is undetectable (< 1 or < 2). If serum hCG is undetectable within 56 days after evacuation, the patient can be discharged from follow-up after an additional four monthly measurements. If serum hCG is first normalised after 56 days, the patient is follow-up with monthly serum hCG measurement for six months. Safe contraception should be used during the follow-up period (A). If hCG stagnates (less than 10% fall over three measurements), increases, or if hCG can be demonstrated for longer than 6 months, the patient by definition has persistent trophoblastic disease (PTD). A chest X-ray should be taken and a gynaecologic ultrasound scanning performed. The patient is referred to oncologic treatment (A). Uterine re-evacuation as a treatment for PTD can, in general, not be recommended because the rate of remission is low, and there is the risk of perforation of the uterus (C). In all following pregnancies, the woman is offered an early ultrasound scan, e.g. in gestational week eight (D). Eight weeks after termination of all future pregnancies, serum hCG is measured (D). In PTD and invasive hydatidiform mole, the primary treatment is MTX, either orally every third week or IV every week (B). In MTX-resistant PTD, IV act D is added (or replaces the MTX) (B). Third line chemotherapy is BEP or EP, alternatively EMA-CO (B). Choriocarcinoma is primarily treated with chemotherapy. Hysterectomy and/or resection of metastases are possible treatments (A). Placental site trophoblastic tumour (PSTT) and epithelioid trophoblastic tumour (ETT) are primarily treated with hysterectomy. In the case of disseminated disease, chemotherapy is considered (A). The risk of reoccurrence after trophoblastic disease treated with chemotherapy is approximately 3%. Most reoccurrences are seen within 12 months, and for this reason monitoring of hCG is recommended for one year, the first third months once or twice a month, thereafter every second to third month. Patients with PSTT and ETT are monitored with measurement of hCG throughout their lifetimes (C). In genetically verified twin pregnancy with hydatidiform mole and a living foetus, the pregnancy can continue if serum hCG is monitored and ultrasound scans regularly performed, and possible obstetric complications dealt with (C). In the case of recurrent hydatidiform mole and/or familial hydatidiform mole, patients should be referred to genetic workup and counselling (C). Women with a hereditary disposition to hydatidiform mole because of a mutation in NLRP7 should be informed of the possibility of becoming pregnant via egg donation (C).