FOXL2 Mutation Analysis of Ovarian Sex Cord-Stromal Tumors: Genotype-Phenotype Correlation With Diagnostic Considerations.

Correlation of FOXL2 mutation status with morphologic features and reticulin staining patterns was performed in a comprehensive single-institutional cohort of ovarian sex cord-stromal tumors. Fifty-one cases were included, 35 of which were morphologically diagnosed as adult granulosa cell tumor, 4 as Sertoli-Leydig cell tumor, 11 as fibroma/fibrothecoma and 1 as a thecoma. Of the adult granulosa cell tumors, 31 (88.6%) harbored FOXL2 mutation. Abundant pale cytoplasm was seen in 51.6% (16/31) of FOXL2 mutated tumors, compared with 6.7% (1/15) among FOXL2 wild type tumors (P=0.003). Nearly half of FOXL2 negative tumors showed individual pericellular reticulin staining pattern, while none of the FOXL2 positive cases demonstrated this feature (P=0.0001). Nested reticulin pattern was observed in 67.7% of FOXL2 positive tumors, compared with 20% of FOXL2 negative cases (P=0.004). Indeterminate reticulin staining pattern was seen in nearly one third of cases in both groups. Nested reticulin pattern was 87.5% specific and 67.7% sensitive for FOXL2 mutation, while individual reticulin pattern was 100% specific for absence of FOXL2 mutation. No statistical significance was observed between the 2 groups in tumor size, mitotic activity, nuclear atypia, and nuclear grooves. Follow-up was available for 44 patients ranging from 0.3 to 259 months (mean: 67.5 mo). Two patients developed recurrence, both of them harbored FOXL2 mutation. In conclusion, the pathology diagnosis of sex cord-stromal tumors continues to be difficult, and reticulin staining remains a valuable tool as an initial step in the diagnostic work-up. Individual pericellular reticulin pattern essentially rules out adult granulosa cell tumor, while cases with indeterminate or nested patterns can be subjected to FOXL2 mutation testing to aid the diagnosis.

FOXL2 Mutation Status in Granulosa Theca Cell Tumors of the Ovary.

Ovarian sex-cord stromal tumors that have between 10% and 50% granulosa cells in a prominent fibrothecomatous background have been referred to as granulosa theca cell tumors or mixed granulosa theca cell tumors. The classification and prognosis of these tumors is not clear. Most adult granulosa cell tumors of the ovary harbor a mutation in the FOXL2 gene, whereas fibromas and thecomas lack this mutation. The aim of our study was to assess the FOXL2 mutation status of ovarian granulosa theca cell tumors and to correlate the mutation status with morphologic and clinical characteristics. A FOXL2 mutation was detected in 6 of 12 (50%) granulosa theca cell tumors. Tumors with higher cellularity of granulosa cells were more likely to harbor a FOXL2 mutation as were tumors in which the granulosa cells formed large lobules. No conclusions could be drawn regarding the clinical and prognostic significance of the presence of a mutation given the small number of cases and limited clinical follow-up. Our study shows that half of granulosa theca cell tumors harbor the same FOXL2 mutation that characterizes adult granulosa cell tumors but there is no outcome evidence to guide whether mutation status should alter the classification of the tumor or the management of the patient.

[Sex cord gonadal stromal tumors]. / Tumoren des Gonadenstromas.

According to the World Health Organization (WHO) classification from 2004, sex cord gonadal stromal tumors are divided into Leydig cell tumors, Sertoli cell tumors, granulosa cell tumors, tumors of the thecoma-fibroma group, incompletely differentiated sex cord gonadal stromal tumors, mixed forms of sex cord gonadal stromal tumors and tumors containing both germ cell and sex cord gonadal stromal elements. These tumors can appear sporadically or in combination with hereditary syndromes. To diagnose these rare tumors the combination of characteristic morphological aspects and various immunohistochemical markers is useful. Latest investigations demonstrate the potential role of mutation analyses in the diagnosis of this heterogeneous group of tumors.

Incidental FOXL2 mutated adult granulosa cell tumour of the ovary with thecoma-like foci.

We report on the incidental finding of a FOXL2 mutated adult granulosa cell tumour of the ovary with thecoma-like foci, a rare entity recently described by Jennifer N. Stall and Robert H. Young in a series of sixteen cases in 2019, displaying features differing from conventional adult granulosa cell tumour. Our aim is to specify the morphologic and molecular particularities of this presumably underrecognized finding, with a short presentation of the typical clinical context. Awareness of this rare and challenging neoplasm with indeterminate clinical course is crucial in routine diagnostics.

Mutational analysis of FOXL2 codon 134 in granulosa cell tumour of ovary and other human cancers.

A missense somatic mutation in the FOXL2 gene affecting codon 134 has recently been reported in granulosa cell tumour (GCT) and thecoma of the ovary. Such a recurrent nature of the mutation strongly suggests that the FOXL2 mutation may play an important role in the development of ovarian sex cord-stromal tumours. The aim of this study was to characterize the FOXL2 mutation in human tumour tissues. We analysed 1353 tumour tissues from various origins, including ovarian tumours and other common cancers, by single-strand conformation polymorphism analysis. We found the FOXL2 codon 134 missense mutation in 53 of 56 adult GCTs (94.6%) and two of the 16 thecomas (12.5%), but none in other tumours. Histologically, FOXL2 mutation-negative adult GCT showed that GCT cells were admixed with fibrothecomatous cells, and FOXL2 mutation-positive thecomas showed that luteinized theca cells were predominant. However, immunostaining of either inhibin alpha or FOXL2 did not differentiate the FOXL2 mutation status of adult GCTs and thecomas. There was no FOXL1 mutation and no common oncogenic mutation in the adult GCTs and thecomas. Our data indicate that the FOXL2 codon 134 mutation occurs exclusively in GCT and thecoma, and suggest the possibility that the development of most GCTs and a fraction of thecomas may be dependent on this mutation. Our data also suggest that the FOXL2 mutation status, as well as some histological features, may be important in the diagnosis of ovarian sex cord-stromal tumours.

Evaluation of molecular analysis in challenging ovarian sex cord-stromal tumours: a review of 50 cases.

Molecular profiling was performed in 50 problematic ovarian sex cord-stromal tumours (SCSTs) most of which were seen in consultation. Following analysis, 17 were classified as adult granulosa cell tumour (AGCT), 16 of which showed a FOXL2 sequence variant (mutation); the initial favoured diagnosis in five of the cases was benign thecoma/fibrothecoma. Thirteen tumours ultimately classified as cellular fibroma or thecoma were FOXL2 sequence variant negative which was helpful in excluding AGCT. All six Sertoli-Leydig cell tumours (SLCTs) demonstrated DICER1 'hot spot' sequence variants, and one case each of AGCT and SLCT showed high grade histological transformation associated with a concurrent TP53 sequence variant. All eight unclassified SCSTs were negative for FOXL2 mutations and the six tested cases were DICER1 wild type; however, three tumours demonstrated MET, CTNNB1 or TP53 sequence variants. Four cases were classified as juvenile granulosa cell tumour, and one of these harboured a GNAS sequence variant. The single gynandroblastoma and microcystic stromal tumours in the series demonstrated FOXL2 and CTNNB1 alterations, respectively. In summary, molecular analysis aids in accurate classification of challenging ovarian SCSTs and sometimes leads to revision of the favoured provisional diagnosis. TP53 sequence variants may be associated with dedifferentiation in both SLCTs and AGCTs.

Gynecological tumors in Mulibrey nanism and role for RING finger protein TRIM37 in the pathogenesis of ovarian fibrothecomas.

Mulibrey nanism is an autosomal recessive growth disorder caused by mutations in the TRIM37 gene encoding a protein of unknown function. More than half of female patients with Mulibrey nanism develop benign mesenchymal tumors of ovarian sex cord-stromal origin. In this work, we characterize the gynecological tumors of female patients with Mulibrey nanism in detail. In addition to tumors of the fibrothecoma group, 18% (4/22) of the patients were observed with epithelial neoplasias, including 2 ovarian adenofibromas, 1 ovarian poorly differentiated adenocarcinoma and 1 endometrial adenocarcinoma. To investigate the possible involvement of TRIM37 alterations in the pathogenesis of sporadic fibrothecomas, we analyzed the TRIM37 cDNA for mutations and alternatively spliced transcripts and TRIM37 expression in fibrothecomas of women without Mulibrey nanism. No mutations in the open-reading frame of TRIM37 were detected. Two alternatively spliced variants were found, one lacking exon 23 and one exon 2. TRIM37del2 was also found in normal ovary but in a proportion of sporadic fibrothecomas, the TRIM37del2:TRIM37 ratio was increased. In normal ovary, TRIM37 was localized in the cytoplasm of stromal cells, especially theca cells surrounding developing follicles. TRIM37 transcript was found in all sporadic fibrothecomas examined, but 80% (20/25) of the tumors showed reduced or absent expression of TRIM37 protein. Allelic loss at the TRIM37 locus (17q22-23) was observed in 6% of sporadic fibrothecomas. Nearly half of the sporadic fibrothecomas showed evidence of CpG promoter methylation, suggesting promoter downregulation as one mechanism of reduced TRIM37 expression. In conclusion, inherited biallelic inactivation of TRIM37 (Mulibrey nanism) predisposes to both mesenchymal and epithelial ovarian tumors and dysregulation of TRIM37 may also be involved in the pathogenesis of sporadic fibrothecomas.

Imbalances of chromosomes 4, 9, and 12 are recurrent in the thecoma-fibroma group of ovarian stromal tumors.

Traditional cytogenetic studies of ovarian stromal tumors are few, although trisomy 12 has been frequently documented with fluorescence in situ hybridization (FISH). In the current study, karyotypic analysis of four ovarian stromal tumors and a review of the literature suggest that numerical abnormalities of chromosomes 4 and 9 might also be important, possibly as secondary changes. To determine the frequency of 4, 9, and 12 aneuploidy in a larger group of ovarian tumors, FISH studies were performed on eight fibromas, three thecomas, one fibrothecoma, and five cellular fibromas. Trisomy 12 was identified in all five cellular fibromas as well as in two fibromas and the fibrothecoma. Gain of chromosome 9 was confined to the cellular fibromas. Loss of chromosomes 4 and/or 9 was prominent in the fibromas. These findings confirm the presence of trisomy 12 as a nonrandom chromosomal abnormality in ovarian stromal tumors. Moreover, these conventional and molecular cytogenetic data indicate that gain of chromosome 9 in addition to gain of chromosome 12 is prominent in cellular fibroma. In contrast, loss of chromosomes 4 and/or 9 are recurrent in fibroma. In summary, imbalances of chromosomes 4 and 9 appear to represent important secondary abnormalities in the thecoma-fibroma ovarian tumor group.

Is loss of heterozygosity at 9q22.3 (PTCH gene) and 19p13.3 (STK11 gene) involved in the pathogenesis of ovarian stromal tumors?

Some ovarian fibromas and rare fibrosarcomas are associated with Gorlin syndrome, which is caused by mutation in the human homologue of Drosophila patched gene (PTCH), localized on chromosome 9q22.3. The relationship between PTCH gene and sporadic ovarian tumors in the thecoma-fibroma group has not been well characterized. On the other hand, we have recently described loss of heterozygosity (LOH) at 19p13.3 in 2 sporadic fibromas with sex-cord elements. We have analyzed DNA from 8 fibromas, 6 cellular fibromas, 2 fibrothecomas, 9 luteinized thecomas, and 2 fibrosarcomas of the ovary for LOH at 9q22.3 and 19p13.3, using polymerase chain reaction amplification for 10 microsatellite markers. LOH at 9q22.3 was detected in 4 (67%) of 6 cellular fibromas, with the highest frequency at microsatellite marker D9S15, which localizes proximal to the PTCH gene. Of 9 luteinized thecomas, 2 (22%) also exhibited LOH at 9q22.3 with 3 microsatellite markers other than D9S15. Allelic losses were not detected in any fibroma, fibrothecoma, or fibrosarcoma. LOH at 19p13.3 was found in 2 (25%) of 8 fibromas, 3 (50%) of 6 cellular fibromas, and 1 (11%) of 9 luteinized thecomas. None of the 2 fibrothecomas or 2 fibrosarcomas showed LOH at 19p13.3. LOH at both 9p22.3 and 19p13.3 was observed in 3 (50%) of 6 cellular fibromas, but not in luteinized thecomas. The results indicate that (1) LOH at both PTCH gene and STK11 gene is relatively frequent in cellular fibromas; (2) approximately a quarter of luteinized thecomas exhibited LOH of the PTCH gene; in both neoplasms, cellular fibromas and luteinized thecomas, LOH may play a role in their pathogenesis; and (3) sporadic cellular fibromas may arise through similar genetic pathways as cases of Gorlin syndrome.

Direct luteinizing hormone action triggers adrenocortical tumorigenesis in castrated mice transgenic for the murine inhibin alpha-subunit promoter/simian virus 40 T-antigen fusion gene.

Transgenic (TG) mice, expressing the Simian Virus 40 T-antigen (Tag) under a 6-kb fragment of the murine inhibin alpha-subunit promoter (inh alpha p), develop gonadal tumors of granulosa/theca or Leydig cell origin. We showed previously that adrenocortical tumors develop if the TG mice are gonadectomized but never develop in intact animals. However, if functional gonadectomy was induced by GnRH antagonist treatment or by cross-breeding the TG mice into the hypogonadotropic hpg genetic background, neither gonadal nor adrenal tumors appeared. Since the most obvious difference between the gonadectomized and GnRH-antagonist-treated or Tag/hpg double mutant mice is the elevated gonadotropin secretion in the first group, we examined whether the adrenal tumorigenesis would be gonadotropin-dependent. Surprisingly, both the adrenal tumors and a cell line (C alpha 1) derived from one of them expressed highly functional LH receptors (LHR), as assessed by Northern hybridization, immunocytochemistry, ligand binding, and human CG (hCG)-stimulated cAMP and steroid production. No FSH receptor expression was found in the adrenal tumors by RT-PCR. hCG treatment of the C alpha 1 cells stimulated their proliferation, as measured by [3H]thymidine incorporation. This effect was related to hCG-stimulated steroidogenesis since progesterone, testosterone, and estradiol, at physiological concentrations, also stimulated the C alpha 1 cell proliferation. Different adrenocortical cells expressed initially LHR and Tag, whereas both were highly expressed in the tumor cells. In conclusion, the high level of functional LHR in the adrenal tumors indicates that this receptor can function as tumor promoter when ectopically expressed and stimulated by the ligand hormone.

Numerical and structural chromosome abnormalities in an ovarian fibrothecoma.

Cytogenetic analysis of a fibrothecoma of ovary revealed numerical and structural chromosome abnormalities, i.e., 44,XX, dup(1)(p13p31),del(3)(p14) add (10p), -16, -22. This is the first report of numerical and structural abnormalities in a fibrothecoma of the ovary.

No evidence of somatic activating mutations on gonadotropin receptor genes in sex cord stromal tumors.

OBJECTIVE: To search for somatic activating mutations of gonadotropin receptor (FSH-R and LH/chorionic gonadotropin receptor [CG-R]) genes as a cause of sex cord stromal tumors. DESIGN: Molecular studies in human tissue. SETTING: University hospital. SPECIMEN(S): Eight granulosa cell tumors collected from paraffin-embedded tissue, eight Leydig cell tumors, and three thecomas collected from fresh-frozen or paraffin-embedded tissue. INTERVENTION(S): Tumor samples were used for DNA extraction. The entire exon 11 of the LH/CG-R gene and a hot spot for gonadotropin receptor activating mutations on exon 10 of the FSH-R gene were amplified by polymerase chain reaction. The former was analyzed by denaturing gradient gel electrophoresis and automatic direct sequencing, and the latter by automatic direct sequencing. MAIN OUTCOME MEASURE(S): Results of denaturing gradient gel electrophoresis and automatic direct sequencing. RESULT(S): No somatic activating mutation was detected in exon 11 of the LH/CG-R gene in eight Leydig cell tumors and three thecomas. In addition, no mutations were detected in eight granulosa cell tumors in the hot spot for activating mutations in exon 10 of the FSH-R gene. CONCLUSION(S): Somatic activating mutations of gonadotropin receptors seem to play no relevant role in the development of sex cord stromal tumors.

Histogenetic consideration of ovarian sex cord-stromal tumors analyzed by expression pattern of cytokeratins, vimentin, and laminin. Correlation studies with human gonads.

A total of 30 sex cord-stromal tumors including 9 adult type and 5 juvenile type granulosa cell tumors (GCTs), 4 Sertoli-Leydig cell tumors (SLTs), 1 gynandroblastoma, 5 thecomas, 2 fibromas and 3 sclerosing stromal tumors were immunohistochemically evaluated by means of cytokeratins of different molecular weight, vimentin and laminin with regard to the histogenesis of these tumors and to the embryogenesis of the sex cord and stroma of developing gonads. For comparison, 7 embryonic gonads, 9 fetal and 9 adult ovaries, 14 fetal and 5 postnatal testes, and 1 gonadoblastoma were also examined. The coelomic epithelium of all gonads were positive for both cytokeratins (CAM 5.2 and AE1) and vimentin. In fetal ovaries, the granulosa cells of primordial follicles express low molecular weight cytokeratins only and those cells of more maturing follicles did not express any cytokeratin or vimentin. In adult ovaries, the granulosa cells of primordial follicles coexpressed low molecular weight cytokeratins and vimentin, but those cells of more maturing follicles expressed vimentin only. In fetal testes before 20 weeks gestational age, the Sertoli and Leydig cells did not express any cytokeratins and vimentin. After that time, both cells expressed vimentin only throughout life. The rete ovarii and rete testis from fetal to adult life coexpressed both low molecular weight cytokeratins and vimentin. The rete ovarii in all ages and rete testis in prenatal and childhood ages were surrounded by the laminin-positive basement membrane, however, the rete testis in adult were not. In neoplasia, the GCTs, thecomas, fibromas, and sclerosing stromal tumors expressed vimentin only.(ABSTRACT TRUNCATED AT 250 WORDS)

Numerical chromosome aberrations in fibrothecoma.

Cytogenetic analysis on a 7-day-old culture of a fibrothecoma showed only numerical chromosome abnormalities: 57, XX, +4, +5, +6, +10, +12, +12, +14, +17, +18, +19, +20. The finding of an extra copy of chromosome 12 in mesenchymal tumors, mostly benign and originating from the female genital tract, may possibly point towards their common embryonic origin.

[Detection of extra chromosomes 12 by fluorescent in situ hybridization (FISH) in ovarian stromal tumors. Study of 12 cases and review of the literature]. / Détection de chromosomes 12 surnuméraires par hybridation in situ fluorescente (FISH) dans des tumeurs stromales ovariennes.

Chromosomic aberrations play a major role in the initiation and the progression of benign as well as malignant tumors. In particular, trisomy 12 is frequently observed in female genitourinary tract tumors and constitutes a recurrent and often unique anomaly in stromal ovarian tumors such as fibrothecomas. Today, the genetic analysis of fresh or fixed solid tumors is enabled by the fluorescent in situ hybridization method (FISH). Using FISH and/or conventional cytogenetics, we analysed 12 ovarian stromal tumors (6 fibromas, 3 fibro thecomas and 3 thecomas). All of these tumors were benign and trisomy 12 was observed in all cases. Moreover, 3 cases presented trisomy and tetrasomy for chromosome 12 simultaneously. The high frequency of trisomy 12 in this tumor type suggests that this abnormality might be implicated in ovarian tumorigenesis.

Trisomy 12 and 4 in a thecoma of the ovary.

Cytogenetic analysis of short-term tissue culture from a thecoma of the ovary demonstrated the presence of trisomies of chromosomes 12 and 4 in all analyzed cells. Our finding confirms the consistency with which trisomy 12 is observed in benign sex cord/stromal tumors and suggests that trisomy 4 may be a second event in tumorigenesis of thecoma.

Trisomy of chromosome 12 in a case of thecoma of the ovary.

Cytogenetic analysis was performed after short-term tissue culture of a thecoma of the ovary. Trisomy of chromosome 12 was revealed as the sole chromosome abnormality. This is the first report of a chromosomal aberration in thecoma of the ovary.

Interphase fluorescence in situ hybridization for trisomy 12 on archival ovarian sex cord-stromal tumors.

Trisomy 12 is a nonrandom chromosomal abnormality found in a large proportion of ovarian sex cord-stromal tumors (OSCTs), including thecoma-fibromas (TFs) and granulosa cell tumors (GCTs). The prognostic significance of trisomy 12 in these tumors, however, is unknown. A series of 16 OSCTs, obtained from patients with long-term follow-up, was analyzed for the presence of trisomy 12 by interphase fluorescence in situ hybridization on paraffin-embedded sections. Sections of the contralateral nonneoplastic ovary were available in five cases and utilized as controls. Evidence of trisomy 12 was detected in 9 of 10 TFs, and contrary to previous reports, in only one of six GCTs. One TF with trisomy 12 was a malignant variant that resulted in the death of the patient in 5 months, but the remaining TFs with trisomy 12 were cytologically and clinically benign in those with follow-up available. The single GCT with trisomy 12 was a nonaggressive, stage 1 lesion without evidence of recurrence after 264 months, whereas those GCTs without trisomy 12 included one stage 2 tumor and a cytologically atypical GCT with tumor necrosis and an elevated number of mitotic figures. The evidence suggests that the great majority of OSCTs with trisomy 12 is clinically benign, but not all benign OSCTs have trisomy 12. We conclude that the presence of trisomy 12 is of limited prognostic usefulness in OSCTs.

Clinical study of multi-drug resistance gene (MDR1) expression in primary ovarian cancer.

This study was designed to measure the multi-drug resistance gene (MDR1) mRNA content and analyze clinical relationship between MDR1 expression and drug resistance in primary ovarian cancer. Reverse transcription PCR (RT-PCR) was used to measure MDR1 mRNA content in biopsy sample of 31 primary ovarian cancers (experimental group) and 30 gynecological tumors (control group). The level of 95.2% (20/21) MDR1 expression was relatively low, and the detected rate of MDR1 expression was 67.7% (21/31) in experimental group, which was higher than that in control group (40.0%, P < 0.05). The differences of MDR1 expression between the effective group and no effect group after combined chemotherapy was significant (P < 0.05). No significant relationship was found between MDR1 expression and clinical stage or histological classification or grade of differentiation in experimental group. We are led to concluded that primary ovarian cancers have drug-resistance clones which might express MDR1 spontaneously and expression of MDR1 may be used as a prognostic and predictive indicator for clinical response of ovarian cancers to combined chemotherapy.