This guideline reviews the clinical evaluation and management of gestational trophoblastic diseases, including surgical and medical management of benign, premalignant, and malignant entities. The objective of this guideline is to assist health care providers in promptly diagnosing gestational trophoblastic diseases, to standardize treatment and follow-up, and to ensure early specialized care of patients with malignant or metastatic disease. General gynaecologists, obstetricians, family physicians, midwives, emergency department physicians, anaesthesiologists, radiologists, pathologists, registered nurses, nurse practitioners, residents, gynaecologic oncologists, medical oncologists, radiation oncologists, surgeons, general practitioners in oncology, oncology nurses, pharmacists, physician assistants, and other health care providers who treat patients with gestational trophoblastic diseases. This guideline is also intended to provide information for interested parties who provide follow-up care for these patients following treatment. Women of reproductive age with gestational trophoblastic diseases. Women diagnosed with a gestational trophoblastic disease should be referred to a gynaecologist for initial evaluation and consideration for primary surgery (uterine evacuation or hysterectomy) and follow-up. Women diagnosed with gestational trophoblastic neoplasia should be referred to a gynaecologic oncologist for staging, risk scoring, and consideration for primary surgery or systemic therapy (single- or multi-agent chemotherapy) with the potential need for additional therapies. All cases of gestational trophoblastic neoplasia should be discussed at a multidisciplinary cancer case conference and registered in a centralized (regional and/or national) database. Relevant studies from 2002 onwards were searched in Embase, MEDLINE, the Cochrane Central Register of Controlled Trials, and Cochrane Systematic Reviews using the following terms, either alone or in combination: trophoblastic neoplasms, choriocarcinoma, trophoblastic tumor, placental site, gestational trophoblastic disease, hydatidiform mole, drug therapy, surgical therapy, radiotherapy, cure, complications, recurrence, survival, prognosis, pregnancy outcome, disease outcome, treatment outcome, and remission. The initial search was performed in April 2017 and updated in May 2019.

Relevant evidence was selected for inclusion in the following order:

meta-analyses, systematic reviews, guidelines, randomized controlled trials, prospective cohort studies, observational studies, non-systematic reviews, case series, and reports. Additional significant articles were identified through cross-referencing the identified reviews. The total number of studies identified was 673, with 79 studies cited in this review. The content and recommendations were drafted and agreed upon by the authors. The Executive and Board of Directors of the Society of Gynecologic Oncology of Canada reviewed the content and submitted comments for consideration, and the Board of Directors for the Society of Obstetricians and Gynaecologists of Canada approved the final draft for publication. The quality of evidence was rated using the criteria described in the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology framework. See the online appendix tables for key to grading and interpretation of recommendations. These guidelines will assist physicians in promptly diagnosing gestational trophoblastic diseases and urgently referring patients diagnosed with gestational trophoblastic neoplasia to gynaecologic oncology for specialized management. Treating gestational trophoblastic neoplasia in specialized centres with the use of centralized databases allows for capturing and comparing data on treatment outcomes of patients with these rare tumours and for optimizing patient care.