Complete molar pregnancy in adolescents from North and South America: Clinical presentation and risk of gestational trophoblastic neoplasia

Hydatidiform Mole-Between Chromosomal Abnormality, Uniparental Disomy and Monogenic Variants: A Narrative Review

A hydatidiform mole (HM) or molar pregnancy is the most common benign form of gestational trophoblastic disease characterized by a proliferation of the trophoblastic epithelium and villous edema. Hydatidiform moles are classified into two forms: complete and partial hydatidiform moles. These two types of HM present morphologic, histopathologic and cytogenetic differences. Usually, hydatidiform moles are a unique event, but some women present a recurrent form of complete hydatidiform moles that can be sporadic or familial. The appearance of hydatidiform moles is correlated with some genetic events (like uniparental disomy, triploidy or diandry) specific to meiosis and is the first step of embryo development. The familial forms are determined by variants in some genes, with NLRP7 and KHDC3L being the most important ones. The identification of different types of hydatidiform moles and their subsequent mechanisms is important to calculate the recurrence risk and estimate the method of progression to a malign form. This review synthesizes the heterogeneous mechanisms and their implications in genetic counseling.

Geographical Health District and Distance Traveled Influence on Clinical Status at Admission of Patients with Gestational Trophoblastic Disease

OBJECTIVE

 To assess the potential relationship of clinical status upon admission and distance traveled from geographical health district in women with gestational trophoblastic disease (GTD).

METHODS

 This is a cross-sectional study including women with GTD from the 17 health districts from the São Paulo state (I-XVII), Brazil, referred to the Botucatu Trophoblastic Disease Center (specialized center, district VI), between 1990 and 2018. At admission, hydatidiform mole was assessed according to the risk score system of Berkowitz et al. Gestational trophoblastic neoplasia was evaluated using the International Federation of Gynecology and Obstetrics / World Health Organization (FIGO/WHO) staging/risk score. Data on demographics, clinical status and distance traveled were collected. Multiple regression analyses were performed.

RESULTS

 This study included 366 women (335 hydatidiform mole, 31 gestational trophoblastic neoplasia). The clinical status at admission and distance traveled significantly differed between the specialized center district and other districts. Patients referred from health districts IX (β = 2.38 [0.87-3.88], p = 0.002) and XVI (β = 0.78 [0.02-1.55], p = 0.045) had higher hydatidiform mole scores than those from the specialized center district. Gestational trophoblastic neoplasia patients from district XVI showed a 3.32 increase in FIGO risk scores compared with those from the specialized center area (β = 3.32, 95% CI = 0.78-5.87, p = 0.010). Distance traveled by patients from districts IX (200km) and XVI (203.5km) was significantly longer than that traveled by patients from the specialized center district (76km).

CONCLUSION

 Patients from health districts outside the specialized center area had higher risk scores for both hydatidiform mole and gestational trophoblastic neoplasia at admission. Long distances (>80 km) seemed to adversely influence gestational trophoblastic disease clinical status at admission, indicating barriers to accessing specialized centers.

Outcomes in the management of high-risk gestational trophoblastic neoplasia in trophoblastic disease centers in South America

Background

South America has a higher incidence of gestational trophoblastic disease than North America or Europe, but whether this impacts chemotherapy outcomes is unclear. The purpose of this study was to evaluate outcomes among women with high-risk gestational trophoblastic neoplasia (GTN) treated at trophoblastic disease centers in developing South American countries.

Methods

This retrospective cohort study included patients with high-risk GTN treated in three trophoblastic disease centers in South America (Botucatu and Rio de Janeiro, Brazil, and Buenos Aires, Argentina) from January 1990 to December 2014. Data evaluated included demographics, clinical presentation, FIGO stage, WHO prognostic risk score, and treatment-related information. The primary treatment outcome was complete sustained remission by 18 months following completion of therapy or death.

Results

Among 1264 patients with GTN, 191 (15.1%) patients had high-risk GTN and 147 were eligible for the study. Complete sustained remission was ultimately achieved in 87.1% of cases overall, including 68.4% of ultra high-risk GTN (score ≥12). Early death (within 4 weeks of initiating therapy) was significantly associated with ultra high-risk GTN, occurring in 13.8% of these patients (p=0.003). By Cox’s proportional hazards regression, factors most strongly related to death were non-molar antecedent pregnancy (RR 4.35, 95% CI 1.71 to 11.05), presence of liver, brain, or kidney metastases (RR 4.99, 95% CI 1.96 to 12.71), FIGO stage (RR 3.14, 95% CI 1.52 to 6.53), and an ultra-high-risk prognostic risk score (RR 7.86, 95% CI 2.99 to 20.71). Median follow-up after completion of chemotherapy was 4 years. Among patients followed to that timepoint, the probability of survival was 90% for patients with high-risk GTN (score 7–11) and 60% for patients with ultra-high-risk GTN (score ≥12).

Conclusion

Trophoblastic disease centers in developing South American countries have achieved high remission rates in high-risk GTN, but early deaths remain an important problem, particularly in ultra-high-risk GTN.

New insights in the pathophysiology of complete hydatidiform mole

OBJECTIVE

The majority of complete hydatidiform moles (CHM) are detected on ultrasound examination by the end of the first trimester when they present as multiple sonolucent cysts. To better understand the pathophysiology of this unique placental pathology and improve its prenatal diagnosis and management we have reviewed the ultrasound features of CHM before the appearance of cystic changes.

STUDY DESIGN

We searched our database to identify all women diagnosed with a complete hydatidiform mole confirmed by histopathology who had an ultrasound examination before 9 weeks' gestation. We reviewed their ultrasound reports and all the corresponding images.

RESULTS

The study group included 39 women with a positive pregnancy test and vaginal bleeding, 36 of whom had at least two ultrasound examinations before 9 weeks' gestation. At the first scan (mean gestation age 7 + 1 weeks; SD 1.1), 29 out 39 (74.4%) of CHM presented as a heterogeneous hyperechogenic mass with or without gestational sac and the remaining ten (25.6%) cases as a regular 4-week gestational sac. Cystic molar changes became apparent from the end of the second month of gestation.

CONCLUSION

The development of a CHM follows a well-defined pattern starting with a macroscopically normal gestation sac at 4 weeks, which transforms into a polypoid mass between 5 and 7 weeks of gestation. The hydropic changes of the villous tissue is progressive and rarely visible in utero on ultrasound before 8 weeks of gestation. These findings should allow an earlier diagnosis and assist in the management counselling of women with CHM.