Ovarian tumorlike structures, biovular follicles, and binucleated oocytes in children: their frequency and possible pathologic significance

Low doses of alkylating agents do not harm human ovarian tissue destined for cryopreservation

OBJECTIVE

To investigate the impact of nongonadotoxic doses of alkylating agents on human ovarian cortex.

DESIGN

Retrospective study.

SETTING

Academic research center.

PATIENTS

Biopsies from 78 patients who had undergone ovarian tissue cryopreservation were retrieved and analyzed. Among them, 42 had previously been treated with chemotherapy (alkylating agents, dose <3,400 mg/m2), making up the chemotherapy group, whereas 36 had not been given any chemotherapy, constituting the control group.

MEAN OUTCOME MEASURES

Follicle count and classification, morphology study, immunostaining for apoptosis (cleaved caspase-3), immunostaining for activation (phospho-Akt), fibrosis (Masson's trichrome), and vascularization (von Willebrand factor and smooth muscle actin).

RESULTS

In the prepubertal group, 271 follicles/mm3 were detected in control patients and 501 follicles/mm3 in chemotherapy-exposed subjects. In the adult group, 4,916 follicles/mm3 were found in control patients and 6,570 follicles/mm3 in chemotherapy-exposed patients. No difference in follicle density was observed between the 2 groups in any age category. Neither did we encounter any significant difference in follicle viability according to chemotherapy exposure or age. Proportions of nongrowing follicles were >76% in all age groups, irrespective of chemotherapy exposure, and higher, although not significantly, in the chemotherapy group compared with the control group. There were significantly fewer secondary follicles in the adult chemotherapy group than in the adult control group. Concerning apoptosis, no significant difference was observed between control and chemotherapy subjects in any age groups. Numbers of activated follicles were systematically higher in all age categories in the chemotherapy group than the control group. Areas of atypical follicles were noted in 4 out of 14 prepubertal patients in the chemotherapy group. In these areas, follicle density was 84,570 ± 8,837 follicles/mm3 and all follicles appeared nonviable but showed no sign of apoptosis.

CONCLUSION

Low-dose chemotherapy had no major impact on ovarian tissue, suggesting that ovarian tissue exposed to some chemotherapy before cryopreservation is comparable with ovarian tissue free of any chemotherapy, as clinically demonstrated by high pregnancy rates after ovarian tissue transplantation in women exposed to chemotherapy. Previous chemotherapy should therefore no longer be a contraindication to ovarian tissue cryopreservation.

Acute and chronic effects of oral genistein administration in neonatal mice

Soy-based infant formulas are widely used in the United States and some other countries. These formulas contain high levels of the estrogenic isoflavone genistein, leading to concern that neonatal genistein exposure could cause acute and/or long-term adverse effects on reproductive and other organs. However, previous work to assess genistein effects in rodent models has not typically replicated the route of delivery and/or serum genistein concentrations reported for soy formula-fed human infants. Our objective was to develop a mouse model that more closely mimics the oral genistein exposure and total serum genistein concentrations observed in soy formula-fed infants. Mouse pups were dosed orally with genistein in a soy formula-corn oil emulsion from Postnatal Day (PND) 1 to PND 5, then effects on reproductive and non-reproductive organs were assessed after dosing and during subsequent development. Neonatal treatment resulted in changes both at the completion of dosing (PND 5) and in adult animals. At PND 5, neonatal genistein treatment caused increased relative uterine weight and down-regulation of progesterone receptor in uterine epithelia. Estrogenic effects of genistein were also seen in the neonatal ovary and thymus, which had an increase in the incidence of multioocyte follicles (MOFs) and a decrease in thymic weight relative to body weight, respectively. The increased incidence of MOFs persisted into adulthood for neonatally treated genistein females, and estrous cycle abnormalities were seen at 6 mo of age despite normal fertility in these mice. The immediate and long-term effects in this neonatal animal model raise concerns that high serum concentrations of genistein are estrogenic and could potentially impact the development of human infants fed soy formula.

Recent Advances in the Pathology and Classification of Gonadal Neoplasms Composed of Germ Cells and Sex Cord Derivatives

In recent years, our understanding of neoplasms composed of germ cells and sex cord derivatives has increased. In this review, advances in the classification and pathology of ovarian germ cell-sex cord-stromal tumors are discussed. Only 2 neoplasms, each with a distinctive pathogenesis and clinicopathologic features, are included in this category. Gonadoblastoma is a tumor that usually occurs in the dysgenetic gonads of intersex patients that have a Y chromosome, whereas mixed germ cell-sex cord-stromal tumor arises in normal gonads in patients without sex chromosomal abnormalities. Ovarian mixed germ cell-sex cord-stromal tumors differ from their testicular counterparts in their histological appearance, immunohistochemical staining reactions, and biological behavior probably because the latter show a greater degree of maturity of their germ cell component. The introduction of cisplatin-based chemotherapy and the application of tumor markers have dramatically improved the clinical outlook for those patients who develop secondary malignant germ cell neoplasms.

Determination and stability of sex

How is the embryonic bipotential gonad regulated to produce either an ovary or a testis? In males, transient early activation of the Y chromosome Sry gene makes both germ cells and soma male. However, in females, available evidence suggests that the process of ovary sex determination may take place independently in the germline and somatic lineages. In addition, in contrast to testis, in ovary somatic cells, female-to-male gonadal sex reversal can occur at times throughout ovary development and maturation. We suggest that a single gene pathway, likely hinging on the Foxl2 transcription factor, both initiates and maintains sex differentiation in somatic cells of the mammalian ovary.

Foxl2 is required for commitment to ovary differentiation

Genetic control of female sex differentiation from a bipotential gonad in mammals is poorly understood. We find that mouse XX gonads lacking the forkhead transcription factor Foxl2 form meiotic prophase oocytes, but then activate the genetic program for somatic testis determination. Pivotal Foxl2 action thus represses the male gene pathway at several stages of female gonadal differentiation. This suggests the possible continued involvement of sex-determining genes in maintaining ovarian function throughout female reproductive life.

Pathologie des hermaphrodismes

Hermaphroditism is a general term referring to all discrepancies between phenotype and genotype of sex development. It must be preferred to sexual ambiguity which refers mainly to external genitalia anomalies. Hermaphroditism is studied on an historical and pathogenetical perspective. Short embryological summaries are integrated. The defects of sexual differentiation due to hormone deficiency are first studied: androgen insensitivity, steroid 5 alpha-reductase 2 deficiency, defects of testosterone synthesis, persistant mullerian ducts syndrome. Sexual determinism deficiencies are then presented: Turner syndrome, XX males, pure gonadal dysgenesis, true hermaphroditism, mixed gonadal dysgenesis, Drash and Frasier syndrome. Tumors of dysgenetic gonads followed. Mixed tumors developed in dysgenetic gonads are gonadoblastoma and dysgerminoma. Sex cord tumors are androgen insensitivity associated tumors, Leydig cells tumors and adrenal cell inclusion tumors. Sex reversion genes open new perspectives.

Biovularity and "coalescence of primary follicles" in ovaries with mature teratomas

Several theories have been postulated regarding the origin of ovarian teratomas, including incomplete twinning, neoplastic proliferation of sequestered totipotent blastomeres or primordial cells, derepression of totipotent genetic information in the nuclei of somatic cells, and parthenogenetic development of germ cells. At present parthenogenetic development of ova is the most widely accepted theory, primarily because of the presence of a 46 XX karyotype in almost all mature teratomas. However, some authors have raised the possibility of fusion of ova in the mechanism of formation of ovarian teratomas. We report the results of a study on ovarian tissue adjacent to 31 teratomas to assess the frequency of biovularity, which could provide evidence favoring the last theory. On the whole we found biovularity in 26 ovaries of young patients (mean age, 27 years) with variable numbers of biovular follicles ranging from 1 in 4 cases to more than 10 in 2 cases; the number of biovular follicles depended on the quantity of ovarian tissue examined as well as on the total number of ova in the tissue. In multiple occasions 2 ova were included within a single follicle; in 24 ovaries the biovularity was correlated with coalescence of primary follicles characterized morphologically by an ovoid or hourglass-like shape that resulted from cohesion of 2 follicles. As control cases, 30 ovaries of patients with an average age of 28 years were examined (12 removed for endometriosis, 8 for serous cystadenoma, 7 for tubal pregnancy, and 3 for acute salpingo-oophoritis). Only 1 ovary with endometriosis contained a single biovular follicle. The results suggest that ovarian teratoma development may result from fusion of ova in ovaries containing biovularity and phenomena of coalescence of primary follicles.