Six months following molar pregnancies, women who have high (although decreasing) human chorionic gonadotropin (hCG) concentrations can be treated with chemotherapy. A study published by The Lancet shows that since these hCG levels will spontaneously fall in most cases, a surveillance-only policy is appropriate and would avoid unnecessary exposure to chemotherapy and its side-effects. The Article is by Professor Michael J Seckl, Charing Cross Hospital at Imperial College Healthcare NHS Trust, London, UK, and colleagues.

Molar pregnancy is an abnormal form of pregnancy. A non-viable, fertilised egg implants in the uterus, and thereby converts normal pregnancy processes into pathological ones. In the UK, about one to three per 1000 pregnancies are either complete or partial moles. Hydatidiform moles can affect women of any reproductive age, but relative risks are higher in those younger than 16 years or older than 45 years than in other age groups. Following molar pregnancies, about 10% of affected women develop gestational trophoblastic disease (GTD), indications for which include raised hCG concentrations 6 months after uterine evacuation of hydatidiform mole, even if those hCG values are falling. In this new research the authors aimed to establish whether chemotherapy is always necessary in these patients.

The study retrospectively identified women registered between January, 1993, and May, 2008 at Charing Cross Hospital, London, UK, who had persistently high hCG concentrations 6 months after evacuation of hydatidiform mole. Rates of hCG normalisation, relapse, and death were assessed in patients continued under surveillance and those who received chemotherapy after 6 months. The authors proposed that a surveillance policy would be clinically acceptable if hCG values returned to normal in 75% of patients or more.

Less than 1% (76 out of 13 960 patients) with hydatidiform moles had persistently high hCG concentrations of more than 5 IU/L 6 months after evacuation. 66 (87%) patients continued under surveillance and hCG values spontaneously returned to normal without chemotherapy in 65 (98%) of these patients. Values in one patient did not become normal because of chronic renal failure, but she remains healthy. Ten patients received chemotherapy, and hCG concentrations returned to normal in eight (80%) of these individuals and remained slightly high in two without any associated clinical problems off treatment. No deaths were recorded.

The authors say: "Our findings suggest that the practice of close surveillance could be adopted in the knowledge that these women are not being exposed to a significantly increased risk of life-threatening gestational trophoblastic neoplasia including placental site trophoblastic tumour."

They conclude: "As far as we are aware, our study is the first to investigate whether continued hCG surveillance is a clinically acceptable approach as opposed to chemotherapy. Our findings directly challenge the present clinical dogma, and provide data showing that continued surveillance for women with high but falling hCG concentrations 6 months after uterine evacuation of a molar pregnancy is clinically acceptable because nearly all patients will spontaneously remit. The results are important because they will change international practice and spare women unnecessary exposure to chemotherapy and its toxic effects."

In a linked Comment, Professor Annie N Y Cheung and Dr Karen K L Chan, University of Hong Kong and Queen Mary Hospital, Hong Kong, China, say: "The present recommendation from the International Federation of Gynecology and Obstetrics (FIGO) for chemotherapy when hCG is high for more than 6 months after evacuation is a compromise between too much and too little treatment. We believe that patients with gestational trophoblastic neoplasia should be managed in centres with dedicated specialists. Centres using various criteria for initiation of chemotherapy, including those adopting FIGO guidelines, should be encouraged to report treatment outcomes so that the recommendations can be updated for improved management of this small but intriguing group of patients."

Professor Seckl is also the lead author of a Case Report, discussing a woman who, after having several molar pregnancies, successfully gave birth to a healthy boy after receiving an egg donated by her cousin. Professor Seckl believes this is the first such report to establish that egg donation can allow successful pregnancy in women with a particular form of genetic mutation that has caused their molar pregnancy.

Source: The Lancet