Case-control study of risk factors for partial molar pregnancy

Thyroid function among women with gestational trophoblastic diseases. A cross-sectional study

BACKGROUND

Gestational trophoblastic diseases (GTDs) are treatable rare tumors with wide distribution. The estimated incidence of GTDs varies dramatically between different regions globally. In early pregnancy, there may be high human chorionic gonadotropin (HCG) concentrations, normal or slightly increased free T4 (fT4) and subnormal thyroid-stimulating hormone (TSH), causing hyperthyroidism ranging from subclinical to severe. Beta-HCG causes thyrotoxicosis through thyroid stimulation in patients with trophoblastic tumors.

OBJECTIVE

To assess thyroid function among patients diagnosed with complete or partial hydatidiform mole, within the GTD spectrum.

DESIGN AND SETTING

Cross-sectional study based on patients' medical records at Van University Hospital, Van, Turkey.

METHODS

50 patients monitored due to diagnoses of hydatidiform mole were included and were examined regarding thyroid function. Thyroid gland size and volume were measured using thyroid ultrasonography. Beta-HCG, TSH, fT4, free T3 (fT3), total T4 (TT4), total T3 (TT3), anti-thyroid peroxidase (anti-TPO), anti-thyroglobulin (anti-TG) and thyroglobulin levels were measured.

RESULTS

Among these patients, 15 (30%) were diagnosed with complete hydatidiform mole and 35 (70%) with partial hydatidiform mole, according to pathology results. Those with complete hydatidiform mole were older (P = 0.003), with higher number of pregnancies (P = 0.032), lower TSH level (P = 0.011) and higher fT4 and TT4 levels (P = 0.04; P = 0.028), compared with partial hydatidiform mole patients.

CONCLUSION

In hydatidiform mole patients, thyroid disease severity increases with age, parity, beta-HCG level and mole size. However, prospective multicenter studies on this topic are needed, with larger numbers of patients and closer monitoring.

Update on the diagnosis and management of gestational trophoblastic disease

Gestational trophoblastic disease (GTD) arises from abnormal placenta and is composed of a spectrum of premalignant to malignant disorders. Changes in epidemiology of GTD have been noted in various countries. In addition to histology, molecular genetic studies can help in the diagnostic pathway. Earlier detection of molar pregnancy by ultrasound has resulted in changes in clinical presentation and decreased morbidity from uterine evacuation. Follow-up with human chorionic gonadotropin (hCG) is essential for early diagnosis of gestational trophoblastic neoplasia (GTN). The duration of hCG monitoring varies depending on histology type and regression rate. Low-risk GTN (FIGO Stages I-III: score <7) is treated with single-agent chemotherapy but may require additional agents; although scores 5-6 are associated with more drug resistance, overall survival approaches 100%. High-risk GTN (FIGO Stages II-III: score >7 and Stage IV) is treated with multiple agent chemotherapy, with or without adjuvant surgery for excision of resistant foci of disease or radiotherapy for brain metastases, achieving a survival rate of approximately 90%. Gentle induction chemotherapy helps reduce early deaths in patients with extensive tumor burden, but late mortality still occurs from recurrent resistant tumors.

Causative Mutations and Mechanism of Androgenetic Hydatidiform Moles

Androgenetic complete hydatidiform moles are human pregnancies with no embryos and affect 1 in every 1,400 pregnancies. They have mostly androgenetic monospermic genomes with all the chromosomes originating from a haploid sperm and no maternal chromosomes. Androgenetic complete hydatidiform moles were described in 1977, but how they occur has remained an open question. We identified bi-allelic deleterious mutations in MEI1, TOP6BL/C11orf80, and REC114, with roles in meiotic double-strand breaks formation in women with recurrent androgenetic complete hydatidiform moles. We investigated the occurrence of androgenesis in Mei1-deficient female mice and discovered that 8% of their oocytes lose all their chromosomes by extruding them with the spindles into the first polar body. We demonstrate that Mei1^-/- oocytes are capable of fertilization and 5% produce androgenetic zygotes. Thus, we uncover a meiotic abnormality in mammals and a mechanism for the genesis of androgenetic zygotes that is the extrusion of all maternal chromosomes and their spindles into the first polar body.

[Partial invasive and metastatic hydatidiform mole: report of a case]

Depuis plusieurs années, la môle hydatiforme partielle(MHP) a été considérée comme une entité bénigne qui ne nécessite pas une surveillance stricte comme celle de la môle complète(MC), mais l'apparition de quelques cas sporadiques de transformation de la môle partielle en maladie trophoblastique persistante que ça soit une môle invasive ou choriocarcinome ou voire même une tumeur du site d'implantation placentaire; a remis en question cette stratégie. A travers une observation d'une môle partielle invasive métastatique, et à travers une revue de la littérature, on a essayé d'appuyer cette conduite qui considère la môle partielle comme une pathologie potentiellement grave nécessitant une prise en charge adéquate et une surveillance assez rigoureuse.

Gestational trophoblastic disease among Hispanic women: A 21-year hospital-based study

OBJECTIVE

Hispanics are the fastest growing minority group in the United States. Few reports have described gestational trophoblastic disease (GTD) in this population. The purpose of this study was to determine the incidence of GTD at our public hospital which primarily serves the Hispanic population.

METHODS

All women diagnosed with GTD (partial and complete hydatidiform mole, choriocarcinoma) between 1983 and 2004 were identified from the institutional tumor registry, surgical pathology reports and hospital ICD-9 codes. Clinical data were retrospectively extracted from medical records. The live birth denominator was tabulated over the same interval of time by retrieving labor and delivery statistics and sorting by race.

RESULTS

GTD was diagnosed in 596 patients over a 21-year study interval encompassing 289,897 live births. The overall incidence of GTD was 2.06/1000 live births. Hispanic women had a higher incidence compared to Blacks (2.38 vs. 1.34; P < 0.001), but not Whites (2.00; P = 0.17). The 416 Hispanic women were diagnosed with GTD at an earlier gestational age in the latter part of this study (12.3 vs. 16.2 weeks; P < 0.001). Hispanics were more likely to have a partial hydatidiform mole compared to Blacks (29% vs. 13%; P < 0.001) and Whites (18%; P = 0.04). Choriocarcinomas occurred least commonly in Hispanic patients (1 per 35,000 live births). Teenage Hispanic women were the only ethnic age group with a higher risk of developing GTD (odds ratio = 1.6, 95% confidence interval: 1.1, 2.2).

CONCLUSION

Hispanic women had the highest incidence of GTD in this hospital-based study, were diagnosed at an earlier gestational age in the last decade and more frequently were diagnosed with partial moles.

Vitamin A and infancy. Biochemical, functional, and clinical aspects

Vitamin A is a very intriguing natural compound. The molecule not only has a complex array of physiological functions, but also represents the precursor of promising and powerful new pharmacological agents. Although several aspects of human retinol metabolism, including absorption and tissue delivery, have been clarified, the type and amounts of vitamin A derivatives that are intracellularly produced remain quite elusive. In addition, their precise function and targets still need to be identified. Retinoic acids, undoubtedly, play a major role in explaining activities of retinol, but, recently, a large number of physiological functions have been attributed to different retinoids and to vitamin A itself. One of the primary roles this vitamin plays is in embryogenesis. Almost all steps in organogenesis are controlled by retinoic acids, thus suggesting that retinol is necessary for proper development of embryonic tissues. These considerations point to the dramatic importance of a sufficient intake of vitamin A and explain the consequences if intake of retinol is deficient. However, hypervitaminosis A also has a number of remarkable negative consequences, which, in same cases, could be fatal. Thus, the use of large doses of retinol in the treatment of some human diseases and the use of megavitamin therapy for certain chronic disorders as well as the growing tendency toward vitamin faddism should alert physicians to the possibility of vitamin overdose.

Less common gynecologic malignancies

OBJECTIVES

To review the incidence, etiology, diagnosis, treatment, and nursing implications of the uncommon gynecologic malignancies of vulvar carcinoma, vaginal carcinoma, sex cord-stromal tumors of the ovary, and gestational trophoblastic tumors.

DATA SOURCES

Research studies, review articles, medical and nursing textbooks.

CONCLUSIONS

Vulvar and vaginal cancers, sex cord-stromal tumors of the ovary, and gestational trophoblastic tumors are rare malignancies constituting less than 5% of all malignant diagnoses. If detected early these malignancies have a high possibility of cure.

IMPLICATIONS FOR NURSING PRACTICE

Nurses play an important role in the education of women and patients to the signs and symptoms of gynecologic malignancies, the disease process, treatment options, follow-up care, and resources available to these women.

Oral contraceptives and risk of gestational trophoblastic disease

Clinical reports suggested that the use of oral contraceptives (OC) after a molar pregnancy may increase the risk of persistent throphoblastic disease. However, few epidemiologic studies have analyzed the effect of OC use on the risk of developing gestational trophoblastic disease (GTD). To give further information, we have analyzed data from a case-control study on risk factors for GTD. Cases were 268 women with a histologically confirmed diagnosis of complete or partial mole referred to the participating Trophoblastic Disease Centers. A total of 268 subjects were interviewed; 79 cases were classified as partial and 159 as complete mole. Controls were randomly selected women who gave birth to healthy infants at term on randomly selected days in the same network of hospitals in which cases had been identified. A total of 104 cases and 130 controls reported ever OC use, and the corresponding odds ratio (OR) was 1.5 (95% CI, 1.1-2.1). The risk of GTD increases with duration of OC use: the OR was 1.7 (95% CI 1.2-2.6) for ever-users reporting >or=12 months of use. No consistent pattern of risk was observed with time since last OC use. We have analyzed separately the association between OC use and risk of complete and partial moles: no statistically significant difference emerged, but the OR for partial moles was higher (OR 3.0, 95% CI 1.6-8.4) than for complete mole (OR 1.0, 95% CI 1.8). In conclusion, we observed a weak association between OC use and GTD; such a weak association could be explained by factors other than causality.

Vitamin A in pregnancy: requirements and safety limits

Most of the functions of vitamin A are mediated through the binding of retinoic acid to specific nuclear receptors that regulate genomic expression. Recent experimental work in transgenic mice showed clearly that normal embryonic development depends on the correct spatial and temporal expression of the receptors in the differentiating cells and on the binding of specific forms of retinoic acid. This implies that the parent compound, vitamin A, is available in adequate forms and quantities. Excessive dietary intake of vitamin A has been associated with teratogenicity in humans in <20 reported cases over 30 y. However, caution must be exercised to avoid unnecessary supplementation of women of childbearing age. Hypovitaminosis A affects millions of women and children worldwide. The main consequence of a poor vitamin A supply during pregnancy is a low vitamin A status at birth and in the next few months. Vitamin A deficiency is strongly associated with depressed immune function and higher morbidity and mortality due to infectious diseases such as diarrhea, measles, and respiratory infections. Vitamin A deficiency is often associated with an increased mother-to-child transmission of HIV-1. The initiation of vitamin A supplementation should be carefully examined in each case according to the risk-to-benefit ratio. The final decision should take into account the estimated vitamin A status of the woman, the availability of vitamin A-rich foods in her diet, and whether supplementation can be supervised.

Oral contraceptive use and risk of gestational trophoblastic tumors

BACKGROUND

Gestational trophoblastic disease refers to a spectrum of rare benign and malignant gynecologic disorders whose pathogenesis is not well understood. Recent studies from China and the United States have raised the hypothesis that long-term use of oral contraceptives before conception may increase the risk of gestational trophoblastic tumors. A multicenter case-control study of gestational trophoblastic tumors was undertaken to test this hypothesis.

METHODS

Telephone interviews were conducted with 235 case patients, including 50 with gestational choriocarcinoma, and 413 control subjects matched on recentness of pregnancy, age at pregnancy, and area of residence. Relative risks (odds ratios) were computed by conditional logistic regression. Reported P values are two-sided.

RESULTS

The relative risk estimate for ever having used oral contraceptives before the index pregnancy was 1.9 (95% confidence interval [CI] = 1.2-3.0), and the risk increased with duration of use (P for trend = .05). The estimate was highest for women who used oral contraceptives during the cycle in which they became pregnant (relative risk = 4.0; 95% CI=1.6-10), but there was no consistent pattern according to the time interval since last use. Separate analyses of choriocarcinoma and persistent mole yielded similar results, i.e., the relative risk estimates for oral contraceptive use were 2.2 (95% CI=0.8-6.4) and 1.8 (95% CI=1.0-3.0), respectively. Control for the number of sexual partners, which was independently associated with risk (P for trend = .05), did not materially change the results.

CONCLUSIONS

This study, the largest to date, indicates that long duration of oral contraceptive use before conception increases the risk of gestational trophoblastic tumors. These findings may provide clues to the pathogenesis of this rare disease. Changes in use of oral contraceptives are not warranted, however, because the incidence attributable to oral contraceptive use is very low.