FOXL2 and TERT promoter mutation detection in circulating tumor DNA of adult granulosa cell tumors as biomarker for disease monitoring

Sex Cord-Stromal Tumors of the Ovary: An Update and Review. Part II - Pure Sex Cord and Sex Cord-Stromal Tumors

We review the time honored but still frequently challenging features of ovarian sex cord-stromal tumors and also emphasize new developments, including unusual morphologic appearances that, despite the relative rarity of many of the tumors, result in a disproportionate number of differential diagnostic problems, variant immunohistochemical profiles, and specific molecular and syndromic associations. These neoplasms are also of historical interest as current knowledge is still based in significant part to the contributions of 2 giants of gynecologic pathology, Dr Robert Meyer and Dr. Robert E. Scully. In part I, we reviewed the pure ovarian stromal tumors. Now, in part II, we present the major clinical, pathologic, and genomic features of pure sex cord and sex cord-stromal tumors.

Relevance of Molecular Pathology for the Diagnosis of Sex Cord-Stromal Tumors of the Ovary: A Narrative Review

Ovarian sex cord-stromal tumors (SCSTs) account for 8% of all primary ovarian neo-plasms. Accurate diagnosis is crucial since each subtype has a specific prognostic and treatment. Apart from fibrosarcomas, stromal tumors are benign while sex cord tumors may recur, sometimes with a significant time to relapse. Although the diagnosis based on morphology is straightforward, in some cases the distinction between stromal tumors and sex cord tumors may be tricky. Indeed, the immunophenotype is usually nonspecific between stromal tumors and sex cord tumors. Therefore, molecular pathology plays an important role in the diagnosis of such entities, with pathognomonic or recurrent alterations, such as FOXL2 variants in adult granulosa cell tumors. In addition, these neoplasms may be associated with genetic syndromes, such as Peutz-Jeghers syndrome for sex cord tumors with annular tubules, and DICER1 syndrome for Sertoli-Leydig cell tumors (SLCTs), for which the pathologist may be in the front line of syndromic suspicion. Molecular pathology of SCST is also relevant for patient prognosis and management. For instance, the DICER1 variant is associated with moderately to poorly differentiated SLCTS and a poorer prognosis. The present review summarizes the histomolecular criteria useful for the diagnosis of SCST, using recent molecular data from the literature.

FOXL2: a gene central to ovarian function

The FOXL2 (forkhead box L2) gene is located on chromosome 3 and encodes for forkhead box (FOX) family of transcription factors which play a critical role in various biological processes. Germline FOXL2 mutations have been identified in blepharophimosis/ptosis/epicanthus inversus syndrome. The somatic missense mutation in FOXL2 (FOXL2 C134W) is now known to be the defining molecular feature of adult-type granulosa cell tumour of the ovary, present in over 90% of cases of this tumour type. Immunohistochemistry for FOXL2 is used as a marker of sex cord-stromal differentiation. However, expression is not restricted to lesions harbouring FOXL2 mutations, and it is positive in a variety of sex cord-stromal proliferations other than adult-type granulosa cell tumour.

Cerebrospinal fluid circulating tumour DNA genotyping and survival analysis in lung adenocarcinoma with leptomeningeal metastases

PURPOSE

The prognosis of patients with leptomeningeal metastasis (LM) remains poor. Circulating tumour DNA (ctDNA) has been proven to be abundantly present in cerebrospinal fluid (CSF); hence, its clinical implication as a biomarker needs to be further verified.

METHODS

We conducted a retrospective study of 35 lung adenocarcinoma (LUAD) patients with LM, and matched CSF and plasma samples were collected from all patients. All paired samples underwent next-generation sequencing (NGS) of 139 lung cancer-associated genes. The clinical characteristics and genetic profiling of LM were analysed in association with survival prognosis.

RESULTS

LM showed genetic heterogeneity, in which CSF had a higher detection rate of ctDNA (P = 0.003), a higher median mutation count (P < 0.0001), a higher frequency of driver mutations (P < 0.01), and more copy number variation (CNV) alterations (P < 0.001) than plasma. The mutation frequencies of the EGFR, TP53, CDKN2A, MYC and CDKN2B genes were easier to detect in CSF than in LUAD tissue (P < 0.05), possibly reflecting the underlying mechanism of LM metastasis. CSF ctDNA is helpful for analysing the mechanism of EGFR-TKI resistance. In cohort 1, which comprised patients who received 1/2 EGFR-TKIs before the diagnosis of LM, TP53 and CDKN2A were the most common EGFR-independent resistant mutations. In cohort 2, comprising those who progressed after osimertinib and developed LM, 7 patients (43.75%) had EGFR CNV detected in CSF but not plasma. Furthermore, patient characteristics and various genes were included for interactive survival analysis. Patients with EGFR-mutated LUAD (P = 0.042) had a higher median OS, and CSF ctDNA mutation with TERT (P = 0.013) indicated a lower median OS. Last, we reported an LM case in which CSF ctDNA dynamic changes were well correlated with clinical treatment.

CONCLUSIONS

CSF ctDNA could provide a more comprehensive genetic landscape of LM, indicating the potential metastasis-related and EGFR-TKI resistance mechanisms of LM patients. In addition, genotyping of CSF combined with clinical outcomes can predict the prognosis of LUAD patients with LM.

Update on Ovarian Sex Cord-Stromal Tumors

This article focuses on the recent advances in ovarian sex cord-stromal tumors, predominantly in the setting of their molecular underpinnings. The integration of genetic information with morphologic and immunohistochemical findings in this rare subset of tumors is of clinical significance from refining the diagnostic and prognostic stratifications to genetic counseling.

Combination of clinical and MRI features in diagnosing ovarian granulosa cell tumor: A comparison with other ovarian sex cord-gonadal stromal tumors

PURPOSE

To evaluate the combination of magnetic resonance imaging (MRI) findings and clinical features in diagnosing ovarian granulosa cell tumor (OGCT) and comparing OGCTs with other ovarian sex cord-gonadal stromal tumors (OSGTs).

METHODS

Women who underwent MRI and were surgically confirmed with OSGTs between January 2015 and January 2022 were included in the study. Histology was used as a primary method of diagnosis. T1WI, T2WI, and DWI MR scans were performed for all patients. All MR images were reviewed by two radiologists. The clinic baseline characteristics of all patients were recorded.

RESULTS

A total of 58 patients were enrolled, with 21 OGCTs found in 20 patients and 39 other OSGTs found in 38 patients. In terms of clinical, the proportion of vaginal discharge/bleeding and menstrual abnormalities were significantly higher in OGCTs than in the control group. A multivariate analysis of the combined clinical MRI revealed that symptomatic, T2 signals of the solid component, Honeycomb-sign, Swiss cheese-sign, and ADC values were independent features for discriminating between OGCTs and other OSGTs. Clinical features, MRI features, and a combined model were established; the areas under the curve of the three models in predicting OGCTs and other OSGTs were 0.694, 0.852, and 0.927, respectively. The DeLong test showed that the combined model had the highest efficiency in predicting OGCTs (p < 0.05), which was significantly different from the AUC of the other two models (p < 0.05).

CONCLUSIONS

Combining clinic and MRI findings helps differentiate OGCTs from other OSGTs. These results help optimize clinical management and indicate that radiologists should focus on clinical information to help improve diagnostic accuracy.

Adult Granulosa Cell Tumor With Sarcomatous Transformation: A Case Study With Emphasis on Molecular Alterations

Adult granulosa cells tumors (AGCTs) are typically low-grade indolent tumors. On rare occasions, they undergo high-grade/sarcomatous transformation and behave aggressively. This transformation is postulated to occur as the result of acquired genetic alterations, some of which may be eligible for targeted therapy. Here we report a rare case of AGCT with sarcomatous transformation that harbored distinct molecular alterations from those typically seen with AGCTs supporting a molecularly driven approach to these malignancies. The patient is a 56-yr-old G3P3 woman with a history of multiple recurrences of ovarian AGCT for which the first diagnosis was made at the age of 25 when she was evaluated for infertility. The ovarian tumor displayed typical features of AGCT with low-grade, bland morphology. The first extraovarian spread of tumor involving the cul-de-sac was reported at the age of 39. After that, recurrences occurred every 2 to 3 yr with involvement of multiple anatomic sites and repeated surgical resections. At the age of 55 she developed a symptomatic recurrence in the pelvis and underwent resection of an isolated lesion (specimen 1) to no gross residual disease. Within 4 wk of resection she developed significant pelvic pain and imaging showed recurrence of the mass. Therefore, in 5 mo after the initial resection she underwent repeat excision of the lesion (specimen 2) and associated bowel. The sections from specimen 1 showed a biphasic morphology: a low-grade component with morphology and immunophenotype consistent with a typical AGCT and a high-grade spindle cell component with features consistent with a high-grade sarcoma. Specimen 2 featured a pure high-grade sarcoma characterized by coagulative tumor cell necrosis, readily recognizable mitoses, highly atypical cells with vesicular nuclei and prominent nucleoli. SF-1 positivity and the presence of FOXL2 C134W mutation in the sarcomatous component support the notion of transformation of typical AGCT. While detected TERT promoter C228T mutation may play a role in this process, we further identified genetic alterations affecting PI3K/AKT/mTOR pathway, including mutations in PIK3CA , PIK3R1 , AKT1 , and NF2 , which may also contribute to tumor progression/transformation. These findings provide rationale for molecular/pathway-based targeted therapy for patients with advanced AGCT.

Update on Ovarian Sex Cord-Stromal Tumors

This article focuses on the recent advances in ovarian sex cord-stromal tumors, predominantly in the setting of their molecular underpinnings. The integration of genetic information with morphologic and immunohistochemical findings in this rare subset of tumors is of clinical significance from refining the diagnostic and prognostic stratifications to genetic counseling.

Transcriptomic Profiling of Gene Expression Associated with Granulosa Cell Tumor Development in a Mouse Model

Ovarian granulosa cell tumors (GCTs) are rare sex cord-stromal tumors, accounting for ~5% ovarian tumors. The etiology of GCTs remains poorly defined. Genetically engineered mouse models are potentially valuable for understanding the pathogenesis of GCTs. Mice harboring constitutively active TGFβ signaling (TGFBR1-CA) develop ovarian GCTs that phenocopy several hormonal and molecular characteristics of human GCTs. To determine molecular alterations in the ovary upon TGFβ signaling activation, we performed transcriptomic profiling of gene expression associated with GCT development using ovaries from 1-month-old TGFBR1-CA mice and age-matched controls. RNA-sequencing and bioinformatics analysis coupled with the validation of select target genes revealed dysregulations of multiple cellular events and signaling molecules/pathways. The differentially expressed genes are enriched not only for known GCT-related pathways and tumorigenic events but also for signaling events potentially mediated by neuroactive ligand-receptor interaction, relaxin signaling, insulin signaling, and complements in TGFBR1-CA ovaries. Additionally, a comparative analysis of our data in mice with genes dysregulated in human GCTs or granulosa cells overexpressing a mutant FOXL2, the genetic hallmark of adult GCTs, identified some common genes altered in both conditions. In summary, this study has revealed the molecular signature of ovarian GCTs in a mouse model that harbors the constitutive activation of TGFBR1. The findings may be further exploited to understand the pathogenesis of a class of poorly defined ovarian tumors.

Renal metastasis of ovarian granulosa cell tumor

Introduction

We would like to present a rare case of metastatic renal tumor.

Case presentation

A 60‐year‐old woman presented to our department with a left renal tumor. She underwent a total hysterectomy and right adnexal resection for a stage IA ovarian granulosa cell tumor approximately 15 years ago, followed by left adnexal resection and postoperative chemotherapy with gemcitabine and paclitaxel 6 years ago. She received six courses of gemcitabine and carboplatin to treat a stage IC clear cell adenocarcinoma of the ovary.

The patient was diagnosed with the left renal tumor and underwent a laparoscopic left nephrectomy. Immunostaining was positive for α‐inhibin and SF‐1 and showed FOXL2 402C→G (C134W) mutation. Finally, the patient was diagnosed with renal metastasis of a granulosa cell tumor.

Conclusion

To our knowledge, this is a very rare case of renal metastasis of a granulosa cell tumor with the FOXL2 mutation in an adult.