Exceptional lymph node recurrence of an unusual ovarian tumor 16 years later: a case report.

BACKGROUND: Sex cord-stromal tumors with annular tubules are a rare tumor accounting for less than 1% of all ovarian malignancies. However, they are characterized by very late recurrence, which can be as late as 30 years after diagnosis and treatment. CASE PRESENTATION: A 16-year-old female Caucasian patient was treated in our department for a stage IA ovarian sex cord-stromal tumors with annular tubules. She underwent a left salpingo-oophorectomy and ipsilateral pelvic node biopsy with no adjuvant treatment. She was seen for amenorrhea after being lost to follow up for 16 years. The diagnosis of recurrence was made by radiology and the elevation of serum inhibin B level. The patient underwent resection of the tumor, left segmental colectomy, and paraaortic lymphadenectomy because the mass was massively adherent to the left mesocolon. Histology confirmed the diagnosis with no metastatic lymph nodes. No adjuvant therapy was indicated. The patient was lost to follow-up again for 4 years and re-presented for amenorrhea. Serum inhibin B level was high. A second recurrence was suggested, and the patient underwent a laparoscopic surgery. We performed left pelvic and paraaortic lymphadenectomy, and 3 months after surgery the patient was pregnant. CONCLUSION: Sex cord-stromal tumors with annular tubules is a slow-growing ovarian tumor with a high potential for recurrence and metastasis. Surgery is the mainstay of treatment. Due to the rarity of these tumors, they are often unsuspected and thus incompletely staged before primary surgery; the diagnosis is made by histological examination. The prognosis of these patients is unknown, and they require long-term follow-up.

The Malignant Potential of Ovarian Steroid Cell Tumors Revisited: A Multi-institutional Clinicopathologic Analysis of 115 Cases.

Steroid cell tumors (SCTs) of the ovary are rare and understudied, and as such, uncertainties remain about their malignant potential, as well as clinicopathologic predictors of patient outcome. Based on a multi-institutional cohort of cases, we present findings from the largest study of SCT reported to date. Clinicopathologic data were documented on 115 cases of SCT that were assembled from 17 institutions. The median patient age was 55 years (range: 9 to 84). When measured, preoperative androgen levels were elevated in 84.2% (48/57) of patients. A total of 111 (96.5%) cases were classified as stage I (103 stage IA; 2 stage IB; 6 stage IC). The stage distribution for the remaining 4 patients was as follows: stage II (n = 1), III (n = 3; 1 IIIA, 1 IIIB, 1 IIIC). The median tumor size was 3 cm (range: 0.2 to 22). Cytologic atypia, microscopic tumor necrosis, microscopic tumor hemorrhage, and a mitotic index of >1 mitotic figure/10 high-power fields were present in 52% (60/115), 9.6% (11/115), 37% (43/115), and 19% (22/115) of cases, respectively. Of 115 patients, 7 (6.1%) recurred postexcision, 4 (3.5%) ultimately died of disease, and 10 (8.7%) either recurred, died of disease, or were advanced stage at presentation. The median duration to recurrence postresection was 33 months (range: 23 to 180). Four of the 7 recurrences were stage IA at baseline. Tumor size >4 cm, International Federation of Gynecology and Obstetrics (FIGO) stage ≥IB, tumor necrosis, and tumor hemorrhage were each significantly associated with reduced recurrence-free survival in log-rank tests and univariable Cox models, with age older than 65 years being of marginal significance (hazard ratio [HR]: 5.4, 95% CI: 1.0-30.0, P = 0.05). Multivariable analyses suggested that FIGO stage ≥IB (HR: 27.5, 95% CI: 2.6-290.5), and age older than >65 years (HR: 21.8, 95% CI: 1.6-303.9) were the only parameters that were independently associated with recurrence. Cross-section analyses showed that tumor necrosis, tumor hemorrhage, and larger tumor size were significantly associated with a FIGO stage ≥IB status, which bolstered the conclusion that they are not independent predictors of recurrence. In summary, <10% of SCTs are clinically malignant, a substantially lower frequency than has previously been reported in the literature. Clinicopathologic predictors of patient outcomes that are prospectively applicable in practice could not be definitively established. Recurrences may occur many years (up to 15 y in this study) after primary resection, even in stage IA cases.

The detailed histopathological characteristics of ovarian fibroma compared with thecoma, granulosa cell tumor, and sclerosing stromal tumor.

BACKGROUND: Ovarian fibromas are benign tumors that can present peculiar morphological features not studied sufficiently. MATERIAL AND METHODS: In this retrospective study, 75 consecutive cases of ovarian fibroma were morphologically compared with 46 thecomas, 16 granulosa cell tumors, and 5 sclerosing stroma tumors for the following factors: the growth pattern as diffuse or nodular, the presence of hyaline plaques, necrosis, keloid-like sclerosis, calcifications, cystic degeneration, fibrous or edematous stroma, prominent vascularity, lutein cells, cellularity, scant or abundant cytoplasm, prominent cell membranes, nuclear grooves, atypia, and mitotic activity. RESULTS: The tumors differed significantly in terms of hyaline plaques presence, nuclear grooves, growth pattern, stroma type, tumor cellularity, cytoplasm, prominence of cell membranes, atypia, mitotic activity, and prominent vascularity. CONCLUSION: Ovarian fibromas can present some maybe unexpected features rather frequently, such as cystic degeneration, hyaline plaques, prominent vascularity, increased cellularity, and some mitotic activity, thus their presence should not always prompt to an alternative diagnosis.

Therapeutic management of uterine tumours resembling ovarian sex cord tumours including a focus on fertility: A systematic review.

OBJECTIVE: Uterine tumours resembling ovarian sex cord tumours (UTROSCTs) are extremely rare. To date, most patients with UTROSCTs have undergone hysterectomy and had a benign clinical course. Fertility-preserving surgery should be considered because some patients with UTROSCTs are aged < 40 years. This paper reviews the treatment and prognosis for patients with UTROSCTs, with a focus on fertility. METHODS: PubMed, MEDLINE and Scopus were searched systematically for case reports and case series of UTROSCTs published in English from inception to December 2022, and initial treatment and recurrence rates were compared. The following data were extracted: age; symptoms; initial therapy; metastasis at diagnosis; disease-free survival (DFS); and recurrence. RESULTS: In total, 147 patients (72 studies) reporting the clinical course of UTROSCTs were analysed. The median age at diagnosis was 50 years, and 28 (19.0 %) patients were aged < 40 years. Most patients (n = 125, 85.0 %) underwent hysterectomy as the initial surgery, with a recurrence rate of 17.6 % (n = 22). The recurrence rate was 30 % (n = 6) in patients who underwent mass resection (n = 20). Among the 15 patients who underwent mass resection aged < 40 years, seven went on to achieve pregnancy (46.7 %) and six had successful deliveries (40.0 %). No significant differences in 5- and 10-year DFS were found between the hysterectomy and mass resection groups (p = 0.123 and 0.0612, respectively). Bilateral salpingo-oophorectomy in addition to hysterectomy was not significantly associated with 10-year DFS (p = 0.548). CONCLUSION: While total hysterectomy is the recommended treatment for UTROSCTs based on recurrence rates, mass resection is an acceptable treatment option for patients who wish to retain their childbearing potential. It is recommended that these women should plan for pregnancy and delivery as soon as possible after mass resection, and should undergo hysterectomy within 5 years.

Review on Sertoli-Leydig Cell Tumours of the Ovary.

Sertoli-Leydig cell tumours (SLCTs) represent a subset of mixed sex cord-stromal tumours (SCSTs), a rare form of non-epithelial ovarian tumours comprising less than 7% of malignant cases. Among other types of SCSTs, SLCTs are one of the more prevalent types observed in young adults. SLCTs are classified into 5 histologic categories based on differentiation levels and histological variants. Diverse chromosomal and genetic mutations have been identified in SLCTs, with the most well-studied being the genetic mutations observed in the Dicer 1, Ribonuclease III (DICER1) and the Forkhead Box L2 (FOXL2) genes. These mutations have important clinical implications and their mechanisms are discussed. Particularly, this review emphasizes the correlation between tumour differentiation, mutation status and virilization. Current common methods and difficulties in the clinical diagnosis of SLCTs are also considered, and the usefulness of immunohistochemistry is highlighted. Patient stratification for treatment is done according to the patient's age, stage of disease and prognostic factors. The gold standard of treatment is surgical resection and adjuvant chemotherapy is administered based on the risk of recurrence. The management of recurrence remains a major challenge. Apart from recurrence, there is also a risk of the development of a metachronous tumour, especially in patients with DICER1 syndrome. Hence, the diagnosis of a SLCT has important implications for genetic testing and patient surveillance even if the management of the tumour is successful. This scoping review serves to consolidate current knowledge on SLCTs and advocates for future research advancements to refine diagnosis, management, and prognosis.

Myoid gonadal stromal tumor of the testis-the novel subtype of testicular gonadal stromal tumors: a case report and review of the literature.

BACKGROUND: Sex cord gonadal stromal tumors compose less than 10% of all testicular neoplasms and consist of a variety of histological subtypes. In 2016, the World Health Organization introduced a novel subtype, the myoid gonadal stromal tumor, that consists of spindle-shaped cells with immunohistologic features of muscle cells. Only few cases have been reported to date. Due to its rarity and owing to its only recent introduction, the current knowledge about myoid gonadal stromal tumor is limited, and particularly, appropriate clinical management is still ill-defined. CASE PRESENTATION: A 47-year-old man of Caucasian descent presented with nonspecific scrotal discomfort. A roundish and well demarcated hypoechoic mass of 8.5 mm in diameter was detected in the cranial region of the left testis. Serum tumor marker levels were within normal ranges. Testis-sparing surgery revealed a 9-mm whitish, hard mass with sharp surgical margin. Histologically, the neoplasm consisted of microfibrillar tissue with spindle-shaped cells harboring elongated nuclei. Immunohistochemical work-up disclosed expression of desmin, small muscle actin, and S100 protein giving evidence for the myogenic nature of the neoplastic cells. There was no indication of malignancy, neither histologically nor clinically. Follow-up of 1 year was uneventful. CONCLUSION: A literature survey revealed 22 previous cases of myoid gonadal stromal tumor. The median age was 37 years, the median size of the neoplasm was 20 mm, and there was no side-preponderance. Myoid gonadal stromal tumor is not much different from other subtypes of gonadal stromal tumors nor from testicular gem cell tumors regarding age and laterality; however, tumor size is smaller in myoid gonadal stromal tumors than in germ cell tumors. Although rarely performed so far, testis-sparing surgery probably constitutes an appropriate treatment of this neoplasm. Myoid gonadal stromal tumor represents an emerging novel entity of benign testicular new growths that caregivers of patients with testicular tumors should be aware of.

Oncological and endocrinological outcomes for children and adolescents with testicular and ovarian sex cord-stromal tumors. Results of the TGM13 National Registry.

RATIONALE: Sex cord-stromal tumors (SCST) are hormonally active and rare. The aim was to describe their endocrinological presentation and outcomes. METHOD: Patients (< 19 years) registered in the TGM13 registry between 2014 and 2021 for SCST were selected. RESULTS: Sixty-three ovarian SCST (juvenile granulosa tumor (JGT) n = 34, Sertoli-Leydig cell tumor (SLCT) n = 17, other SCST n = 12) were included. Median age was 13.1 years (0.4-17.4). Germline DICER1 pathogenic variant was present in 9/17 SLCT. Sixty-one were FIGO stage I (IC n = 14). Adjuvant chemotherapy was administered for 15. Seven had recurrence (FIGO IA n = 3, IX n = 2, III n = 2), leading to one death. With a median follow-up of 42 months (2.5-92), the 3-year progression-free survival (PFS) was 89% (95% CI 76%-95%). Median age was 6.4 years (0.1-12.9) among the 15 testicular SCST (Leydig cell tumor n = 6, JGT n = 5, Sertoli cell tumor n = 3, mixed SCST n = 1). Tumor-nodes-metastases (TNM) stage was pSI in 14. Eight underwent a tumorectomy, 7 an orchiectomy. None experienced recurrence. Endocrinological data were reviewed for 41 patients (18 prepubescent). Endocrine symptoms were present at diagnosis in 29/34 females and 2/7 males (gynecomastia). After a median follow-up of 11 months, 15 patients had persistent endocrine abnormalities: gynecomastia/breast growth (2 males, 1 prepubescent female), precocious/advanced puberty (4 prepubescent females), and hirsutism/menstruation disorders/voice hoarseness/hot flashes (8 pubescent females). The mean height at the last follow-up was within normal ranges (+0.3 standard deviation). CONCLUSIONS: SCSTs have a favorable prognosis. Tumorectomy appears safe with testicular primary. Endocrinological disorders, common at diagnosis, may persist warranting endocrinological follow-up.

18F-FDG PET/CT features of Meigs syndrome induced by ovarian sex cord stromal tumors: a retrospective clinical study.

The objective of this study was retrospectively to analyze the clinical characteristics and 18F-FDG PET/CT findings in Meigs syndrome (MS) patients. A total of 21 patients with MS induced by ovarian stromal tumors and 69 patients with pseudo-MS caused by ovarian cancer (OC-PMS) were subjected to evaluation using 18F-FDG PET/CT. Visual and semi-quantitative methods were employed to analyze the PET/CT findings. Visual analysis included recording whether the density of the primary tumor was uniform, whether there were cystic changes and calcifications, and the location of serous fluid accumulation. Semi-quantitative analysis involved the measurement of the tumor size, SUVmax, and SUVmean. No significant difference was observed in the size and density of primary tumors between the MS group and the OC-PMS group. However, the SUVmax and SUVmean of tumors in the MS group were found to be significantly lower than those in the OC-PMS group. The amount of serous cavity effusion caused by ovarian sex cord stromal tumors was found to be unrelated to the size of the tumor, SUVmax, and SUVmean but was positively correlated with the level of Ca125. MS patients have both benign ovarian tumors and ascites and/or pleural effusion, which may be accompanied by elevated Ca125 levels. This should be considered as one of the differential diagnoses for ovarian cancer. Understanding the PET/CT features of MS can facilitate the attainment of an accurate diagnosis before surgery.

Uterine Tumors Resembling Ovarian Sex Cord Tumors (UTROSCTs): A Scoping Review of 511 Cases, Including 2 New Cases.

Uterine Tumors Resembling Ovarian Sex Cord Tumors (UTROSCTs) are rare uterine mesenchymal neoplasms with uncertain biological potential. These tumors, which affect both premenopausal and postmenopausal women, usually have a benign clinical course. Nevertheless, local recurrences and distant metastases have been described. By analyzing 511 cases retrieved from individual reports and cases series, we provide here the most comprehensive overview of UTROSCT cases available in the literature, supplemented by two new cases of UTROSCTs. Case 1 was an asymptomatic 31-year-old woman who underwent a laparoscopic resection of a presumed leiomyoma. Case 2 was a 58-year-old postmenopausal woman with abnormal vaginal bleeding who underwent an outpatient hysteroscopic biopsy of a suspicious endometrial area. In both cases, immunohistochemical positivity for Calretinin and Inhibin was noted, typical for a sex cord differentiation. In both cases, total laparoscopic hysterectomy with bilateral salpingo-oophorectomy was performed. In light of the available literature, no pathognomonic clinical or imaging finding can be attributed to UTROSCT. Patients usually present with abnormal uterine bleeding or pelvic discomfort, but 20% of them are asymptomatic. In most cases, a simple hysterectomy appears to be the appropriate treatment, but for women who wish to become pregnant, uterus-preserving approaches should be discussed after excluding risk factors. Age, tumor size, lymphovascular space invasion, nuclear atypia, and cervical involvement are not reliable prognostic factors in UTROSCT. The current research suggests that aggressive cases (with extrauterine spread or recurrence) can be identified based on a distinct genetic and immunohistochemical phenotype. For instance, UTROSCTs characterized by GREB1::NCOA1-3 fusions and PD-L1 molecule expression appear to be predisposed to more aggressive behaviors and recurrence, with GREB1::NCOA2 being the most common gene fusion in recurrent tumors. Hence, redefining the criteria for UTROSCTs may allow a better selection of women suitable for fertility-sparing treatments or requiring more aggressive treatments in the future.

[Fundamentals in the pathology of testicular tumours]. / Grundlagen der Pathologie seltener Hodentumoren.

The most common group of testicular tumours comprises germ cell tumours. Other primary testicular tumours are rare, but it is important to be aware of the wide variety of other, much rarer testicular tumours for the differential diagnosis. These tumours include sex cord stromal tumours and testicular adnexal tumours, which must be distinguished from metastases or somatic-type malignancies in germ cell tumours. Immunohistochemical markers and molecular alterations can help to correctly diagnose these tumours.

Contemporary Updates on Sex Cord-stromal Tumors of the Testis.

Testicular sex cord-stromal tumors (TSCSTs) are relatively rare, representing ~5% of testicular neoplasms overall. Historically, TSCSTs have been classified into 3 major entities: Leydig cell tumor, Sertoli cell tumor, and granulosa cell tumor. In recent years, immunophenotypic and molecular analyses have led to a more detailed understanding of the biological and genomic features of these neoplasms, resulting in the description of new entities, some of which have been included in the latest WHO classification. This review summarizes novel histopathologic, clinical, and molecular findings that may lead to a reappraisal of established concepts and help improve the diagnosis and clinical management of TSCSTs in the coming years.

Clinicopathological features and molecular genetic changes in 17 cases of uterine tumor resembling ovarian sex cord tumor.

Uterine tumor resembling ovarian sex cord tumor (UTROSCT) is a rare mesenchymal neoplasm that was recently reported to exhibit recurrent NCOA1-3rearrangement with the most frequent partners ESR1 and GREB1. In this study, the clinicopathological characteristics of 17 UTROSCT cases were summarized; among them, the fusion genes of 12 cases were retrospectively analyzed by targeted RNA sequencing. The mean age of our cohort was 47 years (19-67 y). Although the majority of UTROSCTs had clear boundaries on gross examination, microscopic infiltration into the myometrium was observed in 82.4 % of cases. The tumor cells showed diffuse, trabecular, nested, reticular, pseudopapillary, hollow and solid tubular patterns, expressing sex cord, epithelial, and myogenic markers. Six fusion genes, including ESR1::NCOA3 (n = 4), ESR1::NCOA2 (n = 2), ESR1::CITED2 (n = 2), GREB1::NCOA2 (n = 2), GREB1::NCOA1 (n = 1), and GREB1::NCOA3 (n = 1), were identified. The fusion genes of the three cases with recurrence and metastasis were GREB1::NCOA2, ESR1::NCOA3, and ESR1::CITED2. All 3 cases of recurrent tumors showed infiltrative growth, with moderate to severe dysplasia of tumor cells and different degrees of rhabdomyoid differentiation. This is the first report of the ESR1::CITED2 fusion genes in UTROSCT, and one of the two patients had recurrence and metastasis. Compared with UTROSCT withESR1 rearrangement, UTROSCT with GREB1 rearrangement was more common in elderly patientsand was more likely to present with intramural masses, less sex cord differentiation, poor prognosis, and relapse and metastasis.

Testicular Neoplasms With Sex Cord and Stromal Components Harbor a Recurrent Pattern of Chromosomal Gains.

A small subset of testicular sex cord-stromal tumors, designated as Sertoli-stromal cell tumors (SSCTs), comprises a mixture of Sertoli, spindle, and/or Leydig cells. The clinicopathologic features of these tumors have not been studied in any detail, and their molecular features are unknown. We, therefore, assessed the morphologic and genomic features of 14 SSCTs, including 1 tumor with features similar to the ovarian Sertoli-Leydig cell tumor (SLCT) with retiform tubules. The median age of the patients was 24 years (range, 10-55 years), and the median tumor size was 2.3 cm (range, 0.7-4.7 cm). All tumors showed Sertoli-like sex cord cells arranged in variably developed tubular structures, typically also forming nests and cords. These imperceptibly blended with a neoplastic spindle cell stroma or, in the SLCT, vacuolated to eosinophilic Leydig cells. Genomic analysis demonstrated the presence of a hotspot loss-of-function DICER1 mutation in the SLCT (patient 1) and hotspot gain-of-function CTNNB1 mutations in the tumors of patients 2 and 3, with both CTNNB1 variants being interpreted as possible subclonal events. The mutations were the only relevant findings in the tumors of patients 1 and 2, whereas the tumor of patient 3 harbored concurrent chromosomal arm-level and chromosome-level copy number gains. Among the remaining 11 tumors, all of those that had interpretable copy number data (9 tumors) harbored multiple recurrent chromosomal arm-level and chromosome-level copy number gains suggestive of a shift in ploidy without concurrent pathogenic mutations. The results of the present study suggest that CTNNB1 mutations (likely subclonal) are only rarely present in SSCTs; instead, most of them harbor genomic alterations similar to those seen in testicular sex cord-stromal tumors with pure or predominant spindle cell components. A notable exception was a testicular SLCT with morphologic features identical to the ovarian counterpart, which harbored a DICER1 mutation.

Imaging in gynecological disease (27): clinical and ultrasound characteristics of recurrent ovarian stromal cell tumors.

OBJECTIVE: To describe the clinical and ultrasound characteristics of recurrent granulosa cell and Sertoli-Leydig cell tumors. METHODS: This was a retrospective observational study performed at Fondazione Policlinico Universitario A. Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico, IRCCS, Rome (Gemelli center), Italy. Patients with a histological diagnosis of recurrent granulosa cell tumor or Sertoli-Leydig cell tumor were identified from the database of the Department of Gynecological Oncology. Those who had undergone a preoperative ultrasound examination at the Gemelli center between 2012 and 2020 were included, and the data retrieved from the original ultrasound reports. In all of these reports, the recurrent tumors were described using International Ovarian Tumor Analysis (IOTA) terminology. If a patient had more than one episode of relapse, information from all episodes was collected. If there was more than one recurrent tumor at the same ultrasound examination, all tumors were included. One expert sonographer also reviewed all available ultrasound images to identify typical ultrasound patterns using pattern recognition. RESULTS: We identified 30 patients with a histological diagnosis of recurrent granulosa cell tumor (25 patients, 55 tumors) or Sertoli-Leydig cell tumor (five patients, seven tumors). All 30 had undergone at least one preoperative ultrasound examination at the Gemelli center and were included. These women had a total of 66 episodes of relapse, of which a preoperative ultrasound examination had been performed at the Gemelli center in 34, revealing 62 recurrent lesions: one in 22/34 (64.7%) episodes of relapse, two in 4/34 (11.8%) episodes and three or more in 8/34 (23.5%) episodes. Most recurrent granulosa cell tumors (38/55, 69.1%) and recurrent Sertoli-Leydig tumors (6/7, 85.7%) were classified as solid or multilocular-solid tumors, while 8/55 (14.5%) recurrent granulosa cell tumors and 1/7 (14.3%) recurrent Sertoli-Leydig cell tumors were unilocular cysts and 9/55 (16.4%) recurrent granulosa cell tumors were multilocular cysts. The nine unilocular cysts had contents that were anechoic (n = 2) or had low-level echogenicity (n = 7), had either smooth (n = 4) or irregular (n = 5) internal cyst walls, and ranged in largest diameter from 8 to 38 mm, with three being < 20 mm and five being 20-30 mm. On retrospective review of the images, two typical ultrasound patterns were described: small solid tumor measuring < 2 cm (15/62, 24.2%) and tumor with vascularized echogenic ground-glass-like content (12/62, 19.4%). CONCLUSIONS: Some granulosa cell and Sertoli-Leydig cell recurrences manifest one of two typical ultrasound patterns, while some appear as unilocular cysts. These are usually classified as benign, but in patients being followed up for a granulosa cell tumor or Sertoli-Leydig cell tumor, a unilocular cyst should be considered suspicious of recurrence. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Moderately-differentiated Ovarian Sertoli-Leydig Cell Tumor With a Concurrent Serous Borderline Tumor in a 16-year-old Girl.

Sertoli-Leydig cell tumors (SLCT) are rare tumors of the ovary with a peak incidence in the second to third decade of life. Serous borderline tumors (SBT) are epithelial ovarian neoplasms which occur at a median age of 50 years. A co-occurrence of SLCT and SBT has not yet been reported. Here, we describe a case of a 16-year-old girl who presented with irregular menses, virilization, and an abdominopelvic mass. The mass was surgically removed and an intraoperative consultation revealed an 18.5 cm solid and cystic ovarian mass with the presence of co-existing SLCT and SBT. The diagnosis was confirmed on permanent sections after extensive sampling and immunohistochemical stains. The SLCT showed positive staining for calretinin, inhibin, CD99, and androgen receptor. MART-1 immunostain highlighted the Leydig cells. The SBT showed classic features including hierarchically branching papillae lined by stratified serous epithelium. This pediatric case is the first reported case of a Sertoli-Leydig cell tumor arising in association with a serous borderline tumor.

Teratoma-associated and so-called pure Wilms tumour of the ovary represent two separate tumour types with distinct molecular features.

AIMS: Ovarian Wilms tumour (WT)/nephroblastoma is an extremely rare neoplasm that has been reported to occur in pure form or as a component of a teratomatous neoplasm. We hypothesized that teratoma-associated and pure ovarian WT may represent different tumour types with diverging molecular backgrounds. To test this hypothesis, we comprehensively characterized a series of five tumours originally diagnosed as ovarian WT. METHODS AND RESULTS: The five cases comprised three teratoma-associated (two mature and one immature) and two pure WTs. Two of the teratoma-associated WTs consisted of small nodular arrangements of "glandular"/epithelial structures, while the third consisted of both an epithelial and a diffuse spindle cell/blastemal component. The pure WTs consisted of "glandular" structures, which were positive for sex cord markers (including inhibin and SF1) together with a rhabdomyosarcomatous component. The two pure WTs harboured DICER1 pathogenic variants (PVs), while the three associated with teratomas were DICER1 wildtype. Panel-based DNA sequencing of four of the cases did not identify PVs in the other genes investigated. Analysis of the HA19/IGF2 imprinting region showed retention of imprinting in the pure WTs but loss of heterozygosity with hypomethylation of the ICR1 region in two of three teratoma-associated WTs. Furthermore, copy number variation and clustering-based whole-genome DNA methylation analyses identified divergent molecular profiles for pure and teratoma-associated WTs. CONCLUSION: Based on the morphological features, immunophenotype, and molecular findings (DICER1 PVs, copy number, and DNA methylation profiles), we suggest that the two cases diagnosed as pure primary ovarian WT represent moderately to poorly differentiated Sertoli Leydig cell tumours (SLCTs), while the tumours arising in teratomas represent true WTs. It is possible that at least some prior cases reported as pure primary ovarian WT represent SLCTs.

Lessons from genomic profiling: towards a molecular-based classification of ovarian Sertoli-Leydig cell tumour.

Currently available molecular data support a dichotomous classification of Sertoli-Leydig cell tumours (SLCTs) based on DICER1 mutational status. This correspondence suggests a possible roadmap towards a molecular-based classification of SLCT.

FOXL2 Mutation Status in Sex Cord-stromal Tumors Cannot be Predicted by Morphology.

Granulosa-cell tumors (GCTs) are the most common type of malignant ovarian sex cord-stromal tumor (SCST). The histopathologic diagnosis of these tumors can be challenging. A recurrent somatic mutation of the forkhead box L2 (FOXL2) gene has been identified in adult GCT. In this retrospective single-center study of 44 SCST, a morphologic review together with analysis of FOXL2 C134W was evaluated in relation to tumor morphology. In addition, TERT promoter mutation testing was performed. Twelve of 36 cases got an altered diagnosis based on morphology alone. The overarching architectural growth pattern in 32/44 (72.7%) tumors was diffuse/solid with several tumors showing markedly heterogeneous architecture. In correlation to FOXL2 C134W mutation status, cytoplasmic color, and nuclear shape, differed between the FOXL2 C134W positive and FOXL2 C134 W negative groups, but these differences were not significant when comparing them separately. Nineteen of 44 cases underwent TERT promoter sequencing with a positive result in 3 cases; 2 adult GCTs and 1 cellular fibroma. Three patients developed a recurrence of which 2 were FOXL2 C134W positive adult GCTs and the third was an unclassified SCST. In conclusion, the morphologic and immunohistochemical diagnosis of different SCSTs is challenging and one cannot reliably identify FOXL2 mutation-positive tumors solely by morphologic features. Therefore, broad use of molecular analysis of the FOXL2 C134W mutation is suggested for SCSTs, and further studies are needed to evaluate the clinical outcome of these tumors as well as the diagnostic and prognostic implications of TERT promoter mutations.