Sertoli cell tumors of the testis, not otherwise specified: a clinicopathologic analysis of 60 cases

Adipocytic Differentiation in a Sertoli Cell Tumor

Testicular sex cord-stromal tumors are clonal neoplasms, with the majority being of Leydig cell followed by Sertoli cell origins. In Leydig cell tumors, adipocytic differentiation has been previously reported as a possible distinguishing feature, which has not been reported in other sex cord-stromal tumors. Herein, we report a case of a 48-year-old man who presented with an incidentally discovered 1.1 cm testicular mass, for which he underwent partial orchiectomy. Microscopically, the tumor showed features consistent with sex cord-stromal tumor with strong and diffuse nuclear and cytoplasmic reaction for B-catenin immunohistochemistry, supporting the diagnosis of Sertoli cell tumor. A novel adipocytic differentiation, reported previously in Leydig cell tumors, was present in this tumor.

Metastatic Testicular Sex Cord Tumor Harboring a EWSR1::ATF1 Gene Fusion-A Case Report of a Novel Neoplasm: "Inflammatory and Nested Testicular Sex Cord Tumor"

We present a case report of a 54-year-old male with a metastatic testicular sex cord tumor harboring a EWSR1::ATF1 gene fusion. The tumor displayed a solid and nested architecture with sclerotic stroma and variable inflammatory infiltrate, and was positive for SF-1, inhibin, EMA, CD30, and WT1 expression. Further genetic analysis identified a EWSR1::ATF1 gene fusion. Overall findings were consistent with an "inflammatory and nested testicular sex cord tumor," a recently described testicular neoplasm characterized by EWSR1::ATF1 gene fusion and aggressive clinical behavior. Due to the aggressive nature of this entity and the limited response to current treatment options available, identification of potential biomarkers for early diagnosis and targeted therapies are critical. This case report provides important insights into the genomic landscape of testicular sex cord-stromal tumors, especially within the CTNNB1-negative subset of patients with an aggressive clinical course, and further supports the distinction of "inflammatory and nested testicular sex cord tumor" as a separate entity from Sertoli cell tumors due to its characteristic morphological, immunohistochemical and molecular, features and clinical behavior.

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.

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.

Multiparametric Ultrasound for Diagnosing Testicular Lesions: Everything You Need to Know in Daily Clinical Practice

BACKGROUND

Ultrasonography (US) represents the gold standard imaging method for the assessment of testicular lesions (TL). The gray-scale (GSUS) and color-Doppler (CDUS) ultrasound examination allow sonographers to investigate the size, margins, echotexture, and vascular features of TLs with the aim to differentiate benign from malignant lesions. Recently, the use of contrast-enhanced US (CEUS) and sonoelastography (SE) has led to further improvements in the differential diagnosis of TL. Although GSUS and CDUS are often sufficient to suggest the benign or malignant nature of the TL, CEUS can be decisive in the differential diagnosis of unclear findings, while SE can help to strengthen the diagnosis. The contemporary combination of GSUS, CDUS, CEUS, and SE has led to a new diagnostic paradigm named multiparametric US (mp-US), which is able to provide a more detailed characterization of TLs than single techniques alone. This narrative and pictorial review aimed to describe the mp-US appearance of several TLs.

METHODS

An extensive Medline search was performed to identify studies in the English language focusing on the mp-US evaluation of TLs.

RESULTS

A practical mp-US "identity card" and iconographic characterization of several benign and malignant TLs is provided herein.

CONCLUSIONS

The mp-US characterization of TL reported herein can be useful in daily clinical practice.

Molecular Biomarkers With Potential Clinical Application in Testicular Cancer

Testicular germ cell tumors (TGCTs) and sex cord-stromal tumors (SCSTs) are the most common testicular neoplasms. The morphologic spectrum of such tumors is wide, with several histologic subtypes within each group. Testicular tumors often represent a diagnostic challenge, requiring proper identification of their biologic potential for accurate risk stratification and selection of therapy. In the era of precision medicine, molecular biomarkers are increasingly assuming a critical role in the management of patients with cancer. Given the overall rarity of certain types of testicular neoplasms, progress in biomarker research has been relatively slow. However, in recent years, we have witnessed a multitude of important contributions, including both tissue-based and liquid biopsy biomarkers, stemming from important discoveries of tumor pathobiology, accurate histopathological analysis, multi-institutional studies, and genome-wide molecular analyses of specific tumor subtypes. In this review, we provide an overview of the progress in molecular biomarkers of TGCTs and SCSTs, focusing on those with greatest potential for clinical application. In TGCTs, developmental biology has been the key to understanding these tumors and identifying clinically useful biomarkers (from classical serum tumor markers to pluripotency factors and circulating microRNAs of the 371-373 cluster). For SCSTs, studies have focused on tissue biomarkers only, and genome-wide investigations have recently contributed to a better understanding of rare phenotypes and the aggressive biological behavior of some tumors within this nosologic category. Several new biomarkers are moving toward clinical implementation in this field. Therefore, the practicing pathologist should be aware of their strengths and limitations in order to utilize them properly and maximize their clinical benefits.

The sclerosing sertoli cell tumor of the testis: a case report

BACKGROUND

Testicular Sertoli cell tumor (SCT) is very rare sex cord-gonadal stromal tumor, and sclerosing SCT (SSCT) is even rarer. So far, no more than 50 cases of SSCT have been reported. 80% of SSCTs are less than 2 cm in diameter, large volume mass is pretty unusual. SSCT is usually benign with very low malignant potential. However, it is easily misdiagnosed as a malignant tumor resulting in the removal of the entire testicle.

CASE PRESENTATION

A 55-year-old Chinese male patient presented with a six months' history of right testis progressively enlargement and negative tumor markers. The physical examination was nothing special except for swelling in the right testicle. Imaging identified a large mass in right testicle with rich blood. A right radical orchiectomy was performed on suspicion of malignancy. However, the tumor was postoperatively diagnosed as SSCT, which pathologically consisted of a tubular pattern with regular nuclei and embedded in a densely collagenous stroma, as well as diffusely positive for vimentin, β-catenin and synaptophysin. After 7 months of follow up, no evidence of local recurrence and metastasis has been observed.

CONCLUSION

This rare case is helpful to expand the knowledge of the testicular tumor and alert us fully understand the rare variant of SCTs in order to choose the optimal management when they encounter SSCT.

Molecular Correlates of Aggressive Behavior and Biologic Progression in Testicular Sertoli Cell Tumor

Sertoli cell tumor (SCT) is the second most common type of sex cord-stromal tumor in men and ∼10% exhibit malignant behavior. Although CTNNB1 variants have been described in SCTs, only a limited number of metastatic cases have been analyzed, and the molecular alterations associated with aggressive behavior remain largely unexplored. This study evaluated a series of nonmetastasizing and metastasizing SCTs using next-generation DNA sequencing to further characterize their genomic landscape. Twenty-two tumors from 21 patients were analyzed. Cases were divided into metastasizing SCTs and nonmetastasizing SCTs. Nonmetastasizing tumors were considered to have aggressive histopathologic features if they exhibited ≥1 of the following: size > 2.4 cm, necrosis, lymphovascular invasion, ≥ 3 mitoses per 10 high-power fields (HPF), severe nuclear atypia or invasive growth. Six patients had metastasizing SCTs and the remaining 15 had nonmetastasizing SCTs; 5 nonmetastasizing tumors had ≥1 aggressive histopathologic feature(s). Gain-of-function CTNNB1 or inactivating APC variants were highly recurrent in nonmetastasizing SCTs (combined frequency >90%), with arm-/chromosomal-level CNVs, loss of 1p and CTNNB1 LOH occurring exclusively in CTNNB1-mutant tumors with aggressive histopathologic features or size >1.5 cm. Nonmetastasizing SCTs were almost invariably driven by WNT pathway activation. In contrast, only 50% of metastasizing SCTs harbored gain-of-function CTNNB1 variants. The remaining 50% of metastasizing SCTs were CTNNB1-wild-type and harbored alterations in TP53, MDM2, CDKN2A/CDKN2B, and TERT pathways. These findings suggest that aggressive SCTs can arise from progression of CTNNB1-mutant benign SCTs, or from CTNNB1-wild type tumors with alterations of TP53, cell cycle regulation, and telomere maintenance pathways.

Clinicopathologic and molecular spectrum of testicular sex cord-stromal tumors not amenable to specific histopathologic subclassification

A subset of testicular sex cord-stromal tumors (SCST), which includes neoplasms with mixed histology, cannot be classified into a specific histologic subtype. This study evaluated the clinicopathologic, immunophenotypic and molecular features of 26 SCST not amenable to specific classification by expert uropathologists. Median age at diagnosis was 43 years and median tumor size was 2.4 cm. Follow-up information was available for 18 (69%) patients, with evidence of an aggressive clinical course in 6 patients (4 alive with disease, 2 dead of disease 3 months and 6 months after orchiectomy). Microscopically, SCST not amenable to specific classification demonstrated monophasic epithelioid (9/26, 35%), monophasic spindle cell (5/26, 19%), and biphasic or mixed histology (12/26, 46%). One or more aggressive histopathologic features were seen in 11 cases. DNA sequencing was successful in 22 tumors. Pathogenic CTNNB1 and APC alterations were seen in 7 (33%) and 2 (10%) cases, respectively, with additional variants (e.g., CDKN2A, RB1, TP53, BRCA2) being identified in individual cases. Combined evaluation of morphology, sequencing data and beta-catenin immunohistochemistry resulted in reclassification of 6 (23%) tumors as Sertoli cell tumor, not otherwise specified. This was supported by comparing the methylation profiles of a subset of these tumors and those of typical Sertoli cell tumors. Additionally, a subset of 5 neoplasms (19%) with spindle cell or biphasic histology and SMA expression was characterized by hyperdiploid genomes with recurrent chromosomal gains and absence of driver mutations, possibly representing a distinct tumor type. The SCST that remained not amenable to specific histologic classification (15/26, 58%) were enriched for aggressive histologic features and malignant clinical behavior. In conclusion, this study demonstrated that a subset of testicular SCST that were originally not amenable to specific classification could be reclassified by combined evaluation of morphology, immunohistochemistry and molecular data.

[New 2022 WHO classification of testicular tumours]

The 5th edition of the WHO Classification of Tumours: Urinary and Male Genital Tumours includes some important revisions of the testicular tumour classifications, which are summarized in this article. They concern, for example, the definition of tumours of neuroectodermal and neuroendocrine origin. Furthermore, signet-ring stromal tumours and myoid gonadal stromal tumours are listed as separate entities in the section about sex-cord stromal tumours. Moreover, lymphatic neoplasia as well as soft tissue tumours of the urinary and male genital tract are each combined in a common section.

An introduction to the WHO 5th edition 2022 classification of testicular tumours

The 5th edition of the World Health Organisation Blue Book was published recently and includes a comprehensive update on testicular tumours. This builds upon the work of the 4th edition, retaining its structure and main nomenclature, including the use of the term 'germ cell neoplasia in situ' (GCNIS) for the pre-invasive lesion of most germ cell tumours and division from those not derived from GCNIS. While there have been important developments in understanding the molecular underpinnings of testicular cancer, this updated classification paradigm and approach remains rooted in morphology. Nomenclature changes include replacement of the term 'primitive neuroectodermal tumour' by 'embryonic neuroectodermal tumour' based on the non-specificity of the former term and to separate these tumours clearly from Ewing sarcoma. Seminoma is placed in a germinoma family of tumours emphasising relation to those tumours at other sites. Criteria for the diagnosis of 'teratoma with somatic transformation' have been modified to not include variable field size assessments. The word 'carcinoid' has been changed to 'neuroendocrine tumour', with most examples in the testis now classified as 'prepubertal type testicular neuroendocrine tumour'. For sex cord-stromal tumours, the use of mitotic counts per high-power field has been changed to per mm2 for malignancy assessments, and the new entities, 'signet ring stromal tumour' and 'myoid gonadal stromal tumour', are defined. Well-differentiated papillary mesothelial tumour has now been defined as tumour type with a favourable prognosis. Sertoliform cystadenoma has been removed as an entity from testicular adnexal tumours and placed with Sertoli cell tumours.

Sertoli cell tumor in patient with multiple intratesticular cysts

Sertoli cell tumor is a rare type of testicular tumor. In this study, a 70-year-old man was presented with a Sertoli cell tumor with non-classical findings. The patient noticed progressive swelling on the left hemiscrotum. Preoperative ultrasound findings were not consistent with the classic findings of the Sertoli cell tumor. Patients underwent radical left orchiectomy. The testis was multicystic and no clear parenchyma was seen. The pathology report confirmed the diagnosis of a Sertoli cell tumor.

Sex Cord-Stromal Tumors of Testis: A Clinicopathologic and Follow-Up Study of 15 Cases in a High-Volume Institute of China

Objectives

To report the first series of testicular sex cord-stromal tumors (TSCSTs) with detailed clinicopathologic findings and long-term follow-up in the Chinese population.

Patients and Methods

From 2008 to 2018, 15 patients with TSCST were included in our study. The tumors were analyzed for epidemiological parameters, clinical characteristics, tumor markers, therapy, and follow-up data.

Results

The median age of the patients was 28 years (range, 13–80 years). Para-aortic lymph node metastases were detected in 2 patients after radiological evaluation. Orchiectomy was performed in all patients, and the median diameter of the tumor was 1.5 cm (range, 0.5–5.0 cm). Nine Leydig cell tumors (LCTs), 5 Sertoli cell tumors (SCTs), and 1 unclassified type were confirmed after pathologic evaluation. Thirteen patients (86.7%) were categorized as stage I, and 2 patients (13.3%) were categorized as stage II. The median clinical follow-up was 39.0 months (range, 5–97 months), which showed 10 alive patients, such as 1 patient with progression at 40 months after orchiectomy. The 3- and 5-year progression-free survivals were 100 and 90.0%, respectively.

Conclusion

Testicular sex cord-stromal tumor at stages I and II is a rare subtype with benign behavior and a favorable prognosis in the Chinese population. However, lymph node metastases may be the dominant risk factor for patients with TSCST.

Promising Immunotherapy in Metastatic Testicular Sex Cord Stromal Tumours After First-Line Chemotherapy

Background

Testicular sex cord stromal tumours (TSCSTs) are rare, with few studies focusing on the metastatic TSCST prognosis. The value of treatments, including radical orchiectomy (RO) and retroperitoneal lymph node dissection (RPLND), in preventing metastasis is controversial. Additionally, metastatic TSCSTs are resistant to chemotherapy. We aimed to assess the effectiveness and safety of immunotherapy in metastatic TSCSTs after first-line chemotherapy.

Methods

We retrospectively screened patients with testicular tumours undergoing testis surgery between January 2005 and January 2019. Patients with TSCSTs who had undergone testis-sparing surgery (TSS) or RO were identified. The malignant type was defined as metastasis confirmed by pathology. Treatment responses, progression-free survival (PFS), overall survival (OS) and safety were analysed.

Results

Among the 494 testicular tumour patients who received TSS or RO, 11 (2.2%) patients with histologically proven TSCSTs were identified. At the last follow-up, 7 patients survived without tumours, and 4 patients developed metastasis and received first-line cisplatin-based chemotherapy, with 1 of them achieving an objective response. Their PFS times were 1.5, 2.2, 9.0, and 17.0 months, respectively. Two patients received immune checkpoint inhibitors (ICIs) after developing chemotherapy resistance and achieved a partial response up to the last follow-up; one of them experienced Grade 1 adverse events, and the other experienced Grade 2 adverse events during immunotherapy. The median OS time of the 4 patients with metastatic TSCSTs was 32 months.

Conclusions

TSCSTs are rare, and most are benign with a good prognosis. ICIs represent a promising option for improving clinical outcomes in metastatic TSCSTs.

News in the classification of WHO 2022 testicular tumours

The novelties in WHO 5^th edition classification of genitourinary tumours are: a) nomenclature changes, including the replacement of the term "primitive neuroectodermal tumour" with "embryonic-type neuroectodermal tumour" and of "carcinoid" with "neuroendocrine tumour". Also, seminoma is now placed in a "germinoma" family of tumours, while sertoliform cystoadenoma was moved from adnexal tumours to Sertoli cell tumours; b) new entities, specifically signet ring stromal tumour, myoid gonadal stromal tumour and well-differentiated papillary mesothelial tumour.

Testicular Tumors: A Contemporary Update on Morphologic, Immunohistochemical and Molecular Features

Testicular tumors are incredibly diverse and one of the most challenging areas in surgical pathology. Because of the rarity and overlapping features with numerous entities occurring in the testis and paratestis, these tumors pose a diagnostic challenge even to the most experienced general pathologists. In 2016, the latest "World Health Organization (WHO) classification of testicular tumors" was released, which incorporated several updates to the previous 2004 classification system. These updates involved several entities, including germ cell tumors, sex cord-stromal tumors, tumors containing both germ cells and sex-cord stromal cells, a miscellaneous group of testicular tumors and paratesticular tumors. In addition, significant changes were also introduced in the 2018 AJCC TNM staging (8th edition) regarding testicular tumors. The germ cell tumors are divided into 2 major groups; tumors derived from germ cell neoplasia in situ (GCNIS) and those unrelated to GCNIS. The GCNIS associated tumors include seminomatous and nonseminomatous germ cell tumors, which constitute a heterogeneous group of tumors. Non-GCNIS-associated tumors include prepubertal-type teratoma, prepubertal yolk sac tumor, mixed prepubertal-type teratoma and yolk sac tumor and spermatocytic seminoma. In the sex cord-stromal category, the tumors are classified based on their cells of origin. Most are Leydig cell tumors and Sertoli cell tumors; however, several mixed and diverse entities based on cell types are included in this group. Gonadoblastoma is the only tumor in the mixed germ cell and sex cord-stromal tumor category. Because of recent advances in molecular techniques, abundant new genetic information has emerged which helped classify the tumors based on the molecular alterations and provided insights into the tumor pathogenesis. This review focused on the updates related to testicular germ cell tumors and sex cord-stromal tumors and described the morphologic, immunohistochemical and molecular characteristics with an aim to provide a practical diagnostic approach and an update on relevant recent molecular advances.

Immunohistochemical Characterization of 120 Testicular Sex Cord-Stromal Tumors With an Emphasis on the Diagnostic Utility of SOX9, FOXL2, and SF-1

Sex cord-stromal tumors (SCSTs) account for the second most common category of testicular neoplasms and include several entities that may show overlapping morphologies and present diagnostic challenges. We analyzed a cohort of 120 testicular SCSTs and investigated the diagnostic utility of SRY-box transcription factor 9 (SOX9), forkhead box protein L2 (FOXL2), and steroidogenic factor 1 (SF-1) immunohistochemical stains. The results were compared with the more commonly used SCST markers, inhibin α, calretinin, and Wilms' tumor 1 (WT1). SF-1 was overall the most sensitive stain (91%), followed by inhibin α (70%), calretinin (52%), FOXL2 (50%), SOX9 (47%), and WT1 (37%), but sensitivities varied by tumor type. SOX9 and calretinin were more commonly positive in sex cord elements versus stromal elements (62% vs. 27% and 47% vs. 9%, respectively), whereas FOXL2 was more commonly positive in stromal elements versus sex cord elements (100% vs. 55%) when excluding Leydig cell tumors from the stromal category. Although no individual stain was diagnostically specific, some immunophenotypic patterns were noted that may help in the subclassification of SCSTs. We conclude that SOX9, FOXL2, and SF-1 are useful immunohistochemical stains for confirming sex cord-stromal differentiation in testicular tumors and provide increased sensitivity as well as additional diagnostic information, especially when combined with the more commonly used inhibin α, calretinin, and WT1 immunostains. Although morphology is paramount for subclassification of SCSTs, knowledge of certain immunohistochemical patterns may be helpful for diagnostically challenging cases.

[SERTOLI CELL TUMOR OF TESTIS: CASE REPORT]

A 36-year-old male with right scrotal induration visited a local physician and ultrasonography showed a mass in the right testicle. He was referred to our hospital, where an additional ultrasonography examination revealed a 1×1-cm mass with clear borders, a heterogeneous interior, slight hyperintensity, and abundant blood flow in the upper part of the right testis. Contrast-enhanced computed tomography results indicated a massive lesion with an uneven contrast effect in the right testis and no evidence of metastasis, while magnetic resonance imaging showed the tumor with bleeding and internal heterogeneity. All tumor markers were negative. Under a diagnosis of primary germ cell tumor of the testis without metastasis, a high orchiectomy was performed. The pathological diagnosis was sertoli cell tumor. Histopathologically, the tumor was benign and no additional treatment was performed. Three years after the operation, the patient was well and without complications.

A Morphologic and Immunohistochemical Comparison of Nuclear β-Catenin Expressing Testicular Sertoli Cell Tumors and Pancreatic Solid Pseudopapillary Neoplasms Supporting Their Continued Separate Classification

Some recent reports suggested that many Sertoli cell tumors, not otherwise specified (SCTs-NOS) of the testis were analogs of the solid pseudopapillary neoplasm (SPN) of the pancreas. One of the most relied on pieces of information for this assertion was the shared occurrence in both neoplasms of exon 3 mutations of the CTNNB1 gene, which was reflected by nuclear β-catenin expression. We, therefore, compared the morphologic and immunohistochemical features of 18 SCTs-NOS with strong, diffuse nuclear β-catenin expression with 16 SPNs that also showed such positivity. Although there were clear similarities in the light microscopic features of these neoplasms, there were also significant differences that included, in SCT-NOS and SPN, respectively: hollow tubules (53% vs. 0%), sheet-like growth (44% vs. 94%), circumscription (79% vs. 25%), corded or trabecular patterns (81% vs. 31%), formation of papillae or pseudopapillae (24% vs. 69%), growth in nests or clusters (94% vs. 50%), perivascular pseudorosettes (13% vs. 56%), and rhabdoid cytology (6% vs. 50%). Commonly shared morphologic features included signet-ring cells, pale or foamy cytoplasm, myxoid stroma, cyst formation, perivascular hyalinization, and globular or band-like basement membrane deposits. On immunohistochemical study, sex cord markers were frequently positive in SCTs-NOS (steroidogenic factor-1-94%; FOXL2-87%; SOX9-69%; calretinin-60%; Wilms tumor-1-38%; inhibin-29%) whereas all of these markers were negative in the SPNs. We conclude that even though SCT-NOS and SPN share some morphologic features and nuclear immunoreactivity for β-catenin, there remain differences, both morphologically and immunohistochemically, between these neoplasms to the degree that SCT-NOS should not be equated with pancreatic SPN.

Enrico Sertoli and the supporting cells of the testis "Morphology is function"

In 1865, Enrico Sertoli, at the age of 23, published an article in his own name entitled: "About the existence of special branched cells in the seminiferous tubules of the human testis". These were Sertoli's ideal cells; in this paper he arrived at a perspicacious description of the morphology and function of these cells and in the subsequent articles he investigated the topic of spermatogenesis. Despite the importance of Sertoli's discovery, the attention of the scientific literature remained very limited after Sertoli's death for half a century and the partial eclipse finished only in the 1970s of the twentieth century.

Large Cell Calcifying Sertoli Cell Tumor with Macrocalcification in a Partially Resected Testis

Large cell calcifying Sertoli cell tumors (LCCSCTs) are extremely rare, with less than 100 tumors being described to date. Most of the tumors are benign with a few malignant cases, and aggressive behavior is infrequent. These tumors are a type of Sertoli cell tumor, and these tumors comprise less than 0.3% of all testis tumors in Saudi Arabia. They usually occur in boys and young adults and can affect one or both testicles in multifocal form causing microcalcifications. A 28-year-old male visited our hospital with left testis pain. Physical examination of the scrotum revealed that both testicles were normal sized with no palpable mass. Ultrasonography evaluation revealed grade 3 left varicocele and an incidental 9 mm calcified mass in the right testicle, which was further confirmed by MRI. Partial orchiectomy was performed. Clinical data, radiological studies, and morphological and immunohistochemical characteristics were analyzed.

Sertoli Cell Tumors of the Testes: Systematic Literature Review and Meta-Analysis of Outcomes in 435 Patients

BACKGROUND

Sertoli cell tumors (SCTs) of the testes are rare, and the literature provides only weak evidence concerning their clinical course and management. The objective of this study was to summarize evidence on SCTs' clinical presentation, clinicopathological risk factors for malignancy, treatment options, and oncological outcomes.

MATERIALS AND METHODS

Data sources included Medline, Embase, Scopus, the Cochrane Database of Systematic Reviews, and Web of Science. Published case reports, case series, and cohorts were included. Data on clinicopathological variables, treatment of local or metastatic disease, site of metastasis, or survival were extracted from each study considered in this paper, and associations between clinicopathological variables and metastatic disease were analyzed. Whenever feasible, data on individual patients were collected.

RESULTS

Of the 435 patients included, only one (<1%) showed local recurrence after testis-sparing surgery (TSS). Three patients underwent adjuvant retroperitoneal lymphadenectomy. Fifty patients presented with metastases, located in the retroperitoneal lymph nodes (76%), lungs (36%), and bones (16%); median time to recurrence was 12 months. Risk factors for metastatic disease included age, tumor size, necrosis, tumor extension to the spermatic cord, angiolymphatic invasion, and mitotic index. Patients with metastases had a median life expectancy of 20 months. In six patients, metastasectomy resulted in complete remission.

CONCLUSION

Our findings suggest that few local recurrences result after TSS, and no adjuvant therapy can be regarded as a standard of care. Several risk factors are predictive of metastatic disease. Surgery leads to remission in metastatic disease, whereas systemic treatment alone does not result in long-term remission.

IMPLICATIONS FOR PRACTICE

Testicular Sertoli cell tumors usually present without metastatic disease and show low local recurrence rates after testis-sparing surgery; no adjuvant therapy option can be regarded as a standard of care. Patients with risk factors should undergo staging investigations. Those with metastatic disease have poor prognoses, and metastasectomy may be offered in selected cases.

Therapeutic strategies for uncommon testis cancer histologies: teratoma with malignant transformation and malignant testicular sex cord stromal tumors

Testicular cancer is the most common solid malignancy in male adolescents and young adults, with germ cell derived seminomas and non-seminomas being by far the most common histologies. Teratoma with somatic-type malignancy is a rare chemo-resistant phenotype of testis cancer associated with poor prognosis in patients with advanced stage disease. Malignant gonadal-stromal tumors comprise 5% of testicular neoplasms and approximately 10% are malignant and considered chemo-radiation resistant. Prognostic factors and treatment strategies for these uncommon histologies are lacking.

Juvenile Granulosa Cell Tumor of the Testis: Prenatal Diagnosis and Management

Prepubertal primary testicular tumors account for ∼1% of all pediatric solid tumors. We report a new case of prenatal diagnosis of juvenile-type granulosa cell tumor (JGCT). A fetal ultrasound performed at the 38th week of gestation for suspected nonvertex presentation identified a left multilocular septated cystic testicular mass, suggestive for JGCT. At birth, a painless left scrotal mass was detected. Ultrasound re-evaluation excluded torsion of the testis. Tumor markers and abdominal ultrasound were normal for age. Inguinal exploration revealed a cystic mass beneath the tunica albuginea that had replaced all the normal parenchyma. Since organ-sparing surgery was thus not feasible, an orchiectomy was performed and diagnosis of JGCT was confirmed. At 7-year follow-up, the child presented an uneventful outcome. Our case shows that neonatal JGCT, which has an intrauterine genesis, can be diagnosed prenatally by ultrasound in the last weeks of pregnancy.

Genitourinary Pathology Reporting Parameters Most Relevant to the Medical Oncologist

Pathologic variables play an important role in prognostication in urologic malignancies. Histologic subtype, histologic grade, and anatomic extent of disease (pathologic tumor and nodal staging) influence treatment decisions in both the adjuvant and metastatic settings. This article discusses treatment paradigms for the most common urologic malignancies, followed by the evidence base to support the relationship between pathologic assessment and decision making by the medical oncologist.

A Contemporary Review of Common Adult Non-germ Cell Tumors of the Testis and Paratestis

This article provides a comprehensive review of non-germ cell tumors of the testis and paratestis in adults, incorporating the latest 2016 World Health Organization updates. Clinical features, gross pathologic findings, key morphologic details, immunohistochemical profiles, and differential diagnoses are covered, with an emphasis on how to resolve commonly encountered, and sometimes difficult, differential diagnoses.

A contemporary population-based study of testicular sex cord stromal tumours: Presentation, treatment patterns, and predictors of outcome

INTRODUCTION

We aimed to characterize demographic distribution, patient outcomes, and prognostic features of testicular sex cord stromal tumours (SCST) using a large statewide database.

METHODS

Adult male patients diagnosed with SCST between 1988 and 2010 were identified within the California Cancer Registry (CCR). Baseline demographic variables and disease characteristics were reported. Primary outcome measures were cancer-specific survival (CSS) and overall survival (OS). Bivariate and multivariate Cox proportional hazards models were employed to identify predictors of survival.

RESULTS

A total of 67 patients with SCST were identified, of which 45 (67%) had Leydig cell and 19 (28%) had Sertoli cell tumours. Median age was 40 years and the majority of patients (84%) presented with localized disease. Following orchiectomy, nine patients (15%) underwent retroperitoneal lymph node dissection (RPLND), whereas 54 patients (80%) had no further treatment. With a median followup of 75 months, two-year OS and CSS was 91% and 95%, respectively, for those presenting with stage I disease. For those presenting with stage II disease, two-year OS and CSS was 30%. Predictors of worse OS included age >60 (hazard ratio [HR] 5.64; p<0.01) and metastatic disease (HR 8.56; p<0.01). Presentation with metastatic disease was the only variable associated with worse CSS (HR 13.36; p<0.01). Histology was not found to be a significant predictor of either CSS or OS.

CONCLUSIONS

We present the largest reported series to date for this rare tumour and provide contemporary epidemiological and treatment data. The primary driver of prognosis in patients with SCST is disease stage, emphasizing the importance of early detection and intervention.

Perspectives in Pediatric Pathology, Chapter 25. Testicular and Paratesticular Tumors in the Pediatric Age Group

Testicular tumors in the prepubertal age are relatively rare, representing only 9.4% of the total testicular and paratesticular specimens from a 20-year review performed at a large pediatric hospital [ 1 ]. They account for 1% to 2% of all solid tumors in the pediatric age group, with an annual incidence between 0.5/100 000 and 2/100 000 boys according to Coppes et al [ 2 ] and data from the Prepubertal Testicular Tumor Registry [ 3 ]. Similar to other neoplasms afflicting children, a bimodal age distribution is observed. The first peak is between birth and 3 years of age, and a second one occurs at the onset of puberty, extending to the fourth decade. Reports on their frequency vary because some investigators include the adolescent period, while others do not [ 4 ]. The vast majority of testicular tumors are germ cell neoplasms, accounting for 95% across all ages [ 5 ]. In children, germ cell tumors also predominate, representing 71% of all testicular neoplasms. These include yolk sac tumors (49%), teratomas (13%), seminomas and mixed germ cell tumors (9%), and sex-cord stromal tumors (29%). Malignant potential is significantly lower (less than 70%) in the pediatric age group compared to adults (90%) [ 6 ]. According to Pohl et al, 74% of prepubertal testicular tumors are benign [ 7 ].

[Leydig cell, Sertoli cell and adult granulosa cell tumors]

According to the World Health Organization (WHO) classification Leydig cell tumors, Sertoli cell tumors and granulosa cell tumors of the testes belong to the group of sex cord-stromal tumors. These tumors most frequently occur sporadically but in rare cases can be associated with syndromes. These tumor entities show characteristic morphological changes, which in combination with specific immunohistochemical markers facilitate the diagnosis. Recent results of molecular pathological investigations, especially beta-catenin mutation analysis, allow a better categorization of these tumor entities.

The World Health Organization 2016 classification of testicular non-germ cell tumours: a review and update from the International Society of Urological Pathology Testis Consultation Panel

The World Health Organization (WHO) released a new tumour classification for the genitourinary system in early 2016 after consensus by pathologists with expertise in these organs. It utilized the framework of the 2004 classification, and incorporated the most up-to-date information concerning these tumours. In testicular tumours, the majority of the changes occurred in the nomenclature and classification of germ cell tumours; however, several modifications were also made for non-germ cell tumours. Among sex cord-stromal tumours, sclerosing Sertoli cell tumour (SCT) is no longer recognized as a separate entity but as a morphological variant of SCT not otherwise specified (NOS), as CTNNB1 gene mutations have been noted in both neoplasms but not in the other forms of SCT. Similarly, the lipid cell variant is not separately classified, but is considered to be a morphological variant of SCT NOS. Large-cell calcifying SCT is recognized as a distinct entity that occurs either sporadically or in association with Carney complex, with the latter patients having a distinct germline PRKAR1A gene mutation. Intratubular large-cell hyalinizing Sertoli cell neoplasia is also accepted as a separate entity linked with Peutz-Jeghers syndrome. The subcategories of 'mixed' and 'incompletely differentiated' forms of sex cord/gonadal stromal tumours have been replaced by 'mixed and unclassified sex cord-stromal tumours'. New entities introduced in the latest WHO revision include: myoid gonadal stromal tumour and 'undifferentiated gonadal tissue', a putative precursor lesion of gonadoblastoma, whereas juvenile xanthogranuloma and haemangioma are included in the miscellaneous category of tumours.

A CASE OF AN AROMATASE-PRODUCING SERTOLI CELL TUMOR PRESENTING WITH GYNECOMASTIA

A 64-year-old man had complained of a left scrotal mass and gynecomastia since June 2012. A left testicular tumor was suspected and the patient was referred to our department in December 2013. He presented with bilateral gynecomastia and a painless left scrotal mass that was firm, smooth surfaced, and the size of large hen's egg. Levels of markers of testicular germ cell tumors were all within normal range. Endocrinological examination revealed a marked elevation in serum estradiol (E2) level. The patient underwent high inguinal orchiectomy in December 2013.The pathological diagnosis was a Sertoli cell tumor of the left testis. Immunohistochemistry revealed the expression of aromatase synthesis; we speculated that this E2 production by the tumor caused the gynecomastia.Serum E2 level normalized after the orchiectomy. Owing to the diagnosis of malignancy, retroperitoneal lymph node dissection was performed in January 2014. No lymph node metastasis was found in the specimen. The gynecomastia improved gradually, and the patient has been free of disease since the surgery.

Perspectives in Pediatric Pathology, Chapter 11. Testicular Pathology of Hamartomatous Origin

The term hamartoma was coined by Albrecht in 1904 from the Greek μαρτ-άνω, to go wrong [ 1 ]. Hamartoma is currently used to name nonneoplastic lesions composed of disorganized tissue indigenous to the site where it is found. In the testis, this refers to abnormal/excessive development of structures that usually form part of the gonadal parenchyma, epididymis, or spermatic cord. We include the following as hamartomatous lesions of the testis and sperm excretory ducts: cystic dysplasia of the rete testis, rete testis hamartomas, fetal gonadoblastoid testicular dysplasia (FGTD), Sertoli cell nodules, tubular hamartomas, congenital testicular and epididymal lymphangiectasis, and smooth muscle hyperplasia of paratesticular structures. These hamartomas are always benign, but their importance resides in their association with specific disorders, or as markers of complex syndromes.

A survey of DICER1 hotspot mutations in ovarian and testicular sex cord-stromal tumors

Sertoli-Leydig cell tumors are characterized by the presence of somatic DICER1 hotspot mutations. In this study, we sought to define the association between DICER1 hotspot mutations and different morphologic subtypes of ovarian Sertoli-Leydig cell tumors. Furthermore, we aimed to assess whether DICER1 hotspot mutations occur in other ovarian sex cord-stromal tumors, testicular sex cord-stromal tumors, or other female genital tract tumors with rhabdomyosarcomatous differentiation. We subjected a series of ovarian Sertoli-Leydig cell tumors (n=32), Sertoli cell tumors (n=5) and gynandroblastomas (n=5), testicular sex cord-stromal tumors (n=15) and a diverse group of female genital tract tumors with rhabdomyosarcomatous morphology (n=10) to DICER1 hotspot mutation analysis using Sanger sequencing. We also tested two gynandroblastomas for the presence of FOXL2 hotspot mutations (p.C134W; c.402C>G). Twenty of 32 (63%) Sertoli-Leydig cell tumors harbored a DICER1 hotspot mutation, of which 80% had the p.E1705K mutation. No association was found between DICER1 mutation status and the presence of heterologous or retiform differentiation in Sertoli-Leydig cell tumors. DICER1 mutations were found at similar frequencies in gynandroblastoma (2/5; 40%) and ovarian Sertoli cell tumors (5/8; 63%; P>0.1), and all mutated tumors harbored a p.E1705K mutation. DICER1 hotspot mutations were also identified in a single cervical rhabdomyosarcoma and in the rhabdomyosarcomatous component of a uterine carcinosarcoma. No DICER1 mutations were detected in testicular sex cord-stromal tumors. Two DICER1 wild-type gynandroblastomas harbored a p.C134W FOXL2 hotspot mutation in both tumor components. In this study we confirmed that DICER1 hotspot mutations occur in over half of ovarian Sertoli-Leydig cell tumors, and are unrelated to tumor differentiation. We also widened the spectrum of ovarian sex cord-stromal tumors with sertoliform differentiation, in which DICER1 mutations are known to occur, to include Sertoli cell tumors and gynandroblastomas. Our results suggest that DICER1 mutations may not have a role in testicular sex cord-stromal tumorigenesis.

Pathologic Risk Factors in Pediatric and Adolescent Patients With Clinical Stage I Testicular Stromal Tumors

BACKGROUND

Testicular stromal tumors (TSTs) are rare. In adult men with TSTs, various pathologic risk factors have been identified in patients with clinically localized disease that increase the risk of occult metastatic disease (OMD). We systematically reviewed existing literature to analyze the impact of these risk factors on OMD in prepubertal (0 to 12 y) and postpubertal (13 to 21 y) patients.

METHODS

A literature search was conducted using the combination of terms: "testicular stromal tumors," "testicular leydig cell tumors," "testicular sertoli tumors," "testicular interstitial tumors," "testicular granulosa tumor," and "testicular sex cord tumors." Studies of patients 0 to 21 years with clinical stage I TSTs were included.

RESULTS

A total of 100 patients from 31 publications were included with a median age at diagnosis of 5.7 years (range, 1.2 mo to 21 y). Seventy-nine patients were 12 years and below (median 7.2 mo) and 21 patients were 13 to 21 years (median 16 y). No patients in either group were identified to have OMD at retroperitoneal lymph node dissection or during follow-up surveillance (median follow-up 45.6 y; range, 4 to 360 mo). 99% of those 12 years and below versus 95% of those above 12 years had 0 to 1 pathologic risk factors, and 1% versus 5% had 2+ pathologic risk factors (P=0.38).

CONCLUSIONS

Clinical stage I TSTs in adolescent, postpubertal patients appear to behave in a benign manner with few pathologic risk factors, similar to prepubertal patients. Given the low risk of relapse in this population, low-impact surveillance strategies are paramount. Prospective study of these patients is needed, and entry into a tumor registry such as the International Ovarian and Testicular Stromal Tumor Registry is important to learning more about this rare disease.

[Sex cord gonadal stromal tumors]

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.

Overview of pediatric testicular tumors in Korea

Prepubertal testicular tumors are rare compared with postpubertal testicular tumors. The incidence of prepubertal testicular tumors peaks at 2 years of age, tapers off after 4 years of age, and then begins to rise again at puberty. Prepubertal and postpubertal testicular tumors show many differences, including the typical tumor histology, molecular biological differences, and the malignant potential of tumors at different ages. Pediatric testicular tumors are classified as benign or malignant on the basis of their clinical behavior and histologically are divided into germ cell and gonadal stromal (nongerm cell) tumors. Many histological and biological studies have further confirmed the distinct nature of prepubertal and postpubertal testicular tumors. These differences have led to various management strategies for prepubertal and postpubertal tumors. Because overall about 75% of prepubertal testicular tumors are benign, a testis-sparing approach is becoming more common in children. Orchiectomy and observation with very selective use of chemotherapy has become the standard approach when a malignant tumor is identified. Retroperitoneal lymph node dissection and radiation therapy play very limited roles.

Myoid gonadal stromal tumor: a clinicopathologic study of three cases of a distinctive testicular tumor

OBJECTIVES

To report three new cases of testicular myoid gonadal stromal tumor to better characterize its features.

METHODS

The clinicopathologic findings (including follow-up) were evaluated and a review of the literature was performed.

RESULTS

The patients were 38, 43, and 59 years old, and tumor sizes were 1.2, 1.3, and 3.2 cm. All were unilateral, well circumscribed, adjacent to the rete testis, and composed exclusively of spindled cells with elongated nuclei and occasional nuclear grooves arranged in fascicles with admixed variably ectatic blood vessels. Nucleoli were inconspicuous, and the cytoplasm was scant, ill-defined, and pale/lightly eosinophilic. No sex cord component was present. Mitotic figures ranged from zero to five per 10 high-power fields. Significant atypia, lymphovascular invasion, and necrosis were absent. All were consistently positive for smooth muscle actin, S100 protein, FOXL2, and steroidogenic factor 1 but negative for h-caldesmon, calretinin, and SOX9. Inhibin and calponin were focally positive. All patients were alive and well at 5, 31, and 58 months postorchiectomy. Combining our cases with those previously reported (n = 6) shows that this neoplasm occurs mostly in younger men (mean, 37 years), and all follow-up thus far (mean, 25 months) has been benign.

CONCLUSIONS

Myoid gonadal stromal tumors are small (<4 cm) indolent testicular tumors distinctly different from other sex cord-stromal tumors and are adequately managed by orchiectomy.

Adult granulosa cell tumors of the testis: a report of 32 cases

The clinicopathologic features of 32 adult granulosa cell tumors (AGCT) of the testis are presented. The patients were from 14 to 87 years of age (mean 40.0 y) and underwent orchiectomy (n=30) or wedge excision (n=2). None had endocrine-related symptoms. The tumors measured 0.5 to 6.0 cm (mean 2.8 cm) and were predominantly well circumscribed and yellow-tan, except for 1, which had infiltrative borders. The predominant pattern was diffuse, but insular, spindled, microfollicular (Call-Exner bodies), trabecular, corded, watered-silk, palisading, and pseudopapillary patterns were also present. The cells contained round to ovoid nuclei with frequent longitudinal nuclear grooves, indistinct cell borders, and varying amounts of eosinophilic cytoplasm. Most tumors contained limited amounts of fibrocollagenous stroma. The mitotic count ranged from 0 to 18/10 high-power fields (HPF) (mean 4.9/10 HPF, ×400). Two tumors had prominent necrosis, and 1 had vessel invasion. Follow-up information was available for 19 patients, with a mean of 51.0 months (range, 1 to 169 mo). All were without evidence of disease except 1 who had lung metastasis at 24 months. Our findings indicate that the morphologic spectrum of testicular AGCT is similar to that of ovarian AGCT. The majority of testicular examples have a good prognosis (compared with a malignant behavior in 2 of 7 cases in 1 prior series). Lymphovascular invasion, infiltrative borders, and size >4 cm may help in identifying cases with aggressive behavior, as these features were present in the one case with metastasis in our series. Mitotic counts varied and do not appear to be of prognostic significance on the basis of our experience.