Monitoring complete hydatidiform molar pregnancies after normalisation of human chorionic gonadotrophin: national retrospective population study
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Published version
Author(s)
Type
Journal Article
Abstract
Objective To provide evidence for a reduced surveillance protocol to detect gestational trophoblastic neoplasia after normalisation of human chorionic gonadotrophin (hCG) levels following uterine evacuation of a complete hydatidiform mole.
Design National retrospective population study
Setting Two UK Trophoblastic Disease Treatment Centres (Sheffield and London), 1 January 1980 to 30 November 2020.
Participants 17 424 patients with hCG normalisation after evacuation of their complete hydatidiform mole were included. Complete hydatidiform moles were verified by centralised pathological review. Patients were excluded if lost to follow-up or required treatment before normalisation of hCG levels.
Main outcome measures Incidence and clinical presentation of gestational trophoblastic neoplasia after normalisation of hCG levels following uterine evacuation of a complete hydatidiform mole.
Results Of 17 424 patients whose hCG normalised after complete hydatidiform mole evacuation, 99.8% (n=17 393 of 17 424) did not subsequently develop gestational trophoblastic neoplasia. The overall risk of gestational trophoblastic neoplasia after previous normalisation of hCG levels was 0.2% (n=31 of 17 424 patients). The risk of developing gestational trophoblastic neoplasia after uterine evacuation was substantially lower if hCG levels returned to normal in <56 days rather than ≥56 days (posterior medians 0.06%, 95% credible interval 0.01% to 0.14% v 0.22%, 0.15% to 0.31%), with a posterior relative risk of 0.25 (0.06 to 0.72). Most patients who developed gestational trophoblastic neoplasia (71.0%, n=22 of 31) had received a diagnosis after the current six month surveillance protocol. The cumulative risk of developing gestational trophoblastic neoplasia in patients whose hCG levels normalised early increased minimally with time. If a patient had normal hCG levels in <56 days, a clinically relevant time point, the risk of developing gestational trophoblastic neoplasia was small (0.04%, about 1 in 2619 patients) at 39 months after normalisation. The equivalent risk for a patient who had normal hCG levels in ≥56 days was 0.16% (about 1 in 642 patients). All 31 women who developed gestational trophoblastic neoplasia achieved sustained remission after subsequent treatment.
Conclusions The findings of the study indicate that surveillance protocols could safely change to one confirmatory normal hCG value for patients whose hCG levels return to normal in <56 days of evacuation of a complete hydatidiform mole. Patients whose hCG levels return to normal in ≥56 days should be counselled on the remaining risk of gestational trophoblastic neoplasia over time to help decide the length of subsequent follow-up.
Design National retrospective population study
Setting Two UK Trophoblastic Disease Treatment Centres (Sheffield and London), 1 January 1980 to 30 November 2020.
Participants 17 424 patients with hCG normalisation after evacuation of their complete hydatidiform mole were included. Complete hydatidiform moles were verified by centralised pathological review. Patients were excluded if lost to follow-up or required treatment before normalisation of hCG levels.
Main outcome measures Incidence and clinical presentation of gestational trophoblastic neoplasia after normalisation of hCG levels following uterine evacuation of a complete hydatidiform mole.
Results Of 17 424 patients whose hCG normalised after complete hydatidiform mole evacuation, 99.8% (n=17 393 of 17 424) did not subsequently develop gestational trophoblastic neoplasia. The overall risk of gestational trophoblastic neoplasia after previous normalisation of hCG levels was 0.2% (n=31 of 17 424 patients). The risk of developing gestational trophoblastic neoplasia after uterine evacuation was substantially lower if hCG levels returned to normal in <56 days rather than ≥56 days (posterior medians 0.06%, 95% credible interval 0.01% to 0.14% v 0.22%, 0.15% to 0.31%), with a posterior relative risk of 0.25 (0.06 to 0.72). Most patients who developed gestational trophoblastic neoplasia (71.0%, n=22 of 31) had received a diagnosis after the current six month surveillance protocol. The cumulative risk of developing gestational trophoblastic neoplasia in patients whose hCG levels normalised early increased minimally with time. If a patient had normal hCG levels in <56 days, a clinically relevant time point, the risk of developing gestational trophoblastic neoplasia was small (0.04%, about 1 in 2619 patients) at 39 months after normalisation. The equivalent risk for a patient who had normal hCG levels in ≥56 days was 0.16% (about 1 in 642 patients). All 31 women who developed gestational trophoblastic neoplasia achieved sustained remission after subsequent treatment.
Conclusions The findings of the study indicate that surveillance protocols could safely change to one confirmatory normal hCG value for patients whose hCG levels return to normal in <56 days of evacuation of a complete hydatidiform mole. Patients whose hCG levels return to normal in ≥56 days should be counselled on the remaining risk of gestational trophoblastic neoplasia over time to help decide the length of subsequent follow-up.
Date Issued
2025-04-23
Date Acceptance
2025-01-22
Citation
BMJ Medicine, 2025, 4 (1)
ISSN
2754-0413
Publisher
BMJ Publishing Group
Journal / Book Title
BMJ Medicine
Volume
4
Issue
1
Copyright Statement
© 2025, The Author(s). Published by BMJ Publishing Group Ltd. Open access This is an open access article distributed in accordance with the Creative Commons Attribution 4.0 Unported (CC BY 4.0) license, which permits others to copy, redistribute, remix, transform and build upon this work for any purpose, provided the original work is properly cited, a link to the licence is given, and indication of whether changes were made. See: https://creativecommons.org/ licenses/by/4.0/
License URL
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/40309224
PII: bmjmed-2024-001017
Subjects
DIAGNOSIS
DISEASE
DURATION
General & Internal Medicine
GESTATIONAL TROPHOBLASTIC NEOPLASIA
HCG
Life Sciences & Biomedicine
Medical oncology
Medicine, General & Internal
RISK
Science & Technology
Publication Status
Published
Coverage Spatial
England
Article Number
e001017
Date Publish Online
2025-04-23