Genomic landscape and distinct molecular subtypes of primary testicular lymphoma.

Primary testicular lymphoma (PTL) is a rare lymphoma predominantly occurring in the elderly male population. It is characterized by a limited response to treatment and a heightened tendency towards relapse. Histologically, approximately 90% of PTL cases are classified as diffuse large B-cell lymphomas (DLBCL). Genetic features of PTL were delineated in a limited scope within several independent studies. Some of the articles which analyzed the genetic characterization of DLBCL have incorporated PTL samples, but these have been constrained by small sample sizes. In addition, there have been an absence of independent molecular typing studies of PTL. This report summarizes the common mutational features, copy number variations (CNVs) and molecular typing of PTL patients, based on whole-exome sequencing (WES) conducted on a cohort of 25 PTL patients. Among them, HLA, CDKN2A and MYD88 had a high mutation frequency. In addition, we found two core mutational characteristics in PTL including mutation in genes linked to genomic instability (TP53 and CDKN2A) and mutation in immune-related genes (HLA, MYD88, CD79B). We performed molecular typing of 25 PTL patients into C1 subtype with predominantly TP53 mutations and C2 subtype with predominantly HLA mutations. Notably, mutations in the TP53 gene predicted a poor outcome in most types of lymphomas. However, the C1 subtype, dominated by TP53 mutations, had a better prognosis compared to the C2 subtype in PTL. C2 subtype exhibited a worse prognosis, aligning with our finding that the mechanism of immune escape in PTL was primarily the deletions of HLA rather than PD-L1/PD-L2 alterations, a contrast to other DLBCLs. Moreover, we calculated the tumor mutation burden (TMB) and identified that TMB can predict prognosis and recurrence rate in PTL. Our study underscores the significance of molecular typing in PTL based on mutational characteristics, which plays a crucial role in prognostication and guiding therapeutic strategies for patients.

News in the fifth edition of World Health Organization classification of testicular tumors.

BACKGROUND: The fifth edition of World Health Organization classification of urinary and male genital tumours also brought news regarding testicular tumours. In contrast to the previous editions' radical alterations, the adjustments in the fifth edition are subtle and mostly impact the terminology, categorization of some of the rare tumours and diagnostic criteria. PURPOSE: Acquainting with current terms and tumor classification, which is necessary for good clinical practice.

Management of Germ Cell Tumours of the Testis in Adult Patients. German Clinical Practice Guideline Part I: Epidemiology, Classification, Diagnosis, Prognosis, Fertility Preservation, and Treatment Recommendations for Localized Stages.

INTRODUCTION: This is the first German evidence- and consensus-based clinical guideline on diagnosis, treatment, and follow-up on germ cell tumours (GCTs) of the testis in adult patients. We present the guideline content in two publications. Part I covers the topic's background, methods, epidemiology, classification systems, diagnostics, prognosis, and treatment recommendations for the localized stages. METHODS: An interdisciplinary panel of 42 experts including 1 patient representative developed the guideline content. Clinical recommendations and statements were based on scientific evidence and expert consensus. For this purpose, evidence tables for several review questions, which were based on systematic literature searches (last search was in March 2018) were provided. Thirty-one experts entitled to vote, rated the final clinical recommendations and statements. RESULTS: We provide 161 clinical recommendations and statements. We present information on the quality of cancer care and epidemiology and give recommendations for staging and classification as well as for diagnostic procedures. The diagnostic recommendations encompass measures for assessing the primary tumour as well as procedures for the detection of metastases. One chapter addresses prognostic factors. In part I, we separately present the treatment recommendations for germ cell neoplasia in situ, and the organ-confined stages (clinical stage I) of both seminoma and nonseminoma. CONCLUSION: Although GCT is a rare tumour entity with excellent survival rates for the localized stages, its management requires an interdisciplinary approach, including several clinical experts. Quality of care is highly related to institutional expertise and can be reassured by established online-based second-opinion boards. There are very few studies on diagnostics with good level of evidence. Treatment of metastatic GCTs must be tailored to the risk according to the International Germ Cell Cancer Collaboration Group classification after careful diagnostic evaluation. An interdisciplinary approach as well as the referral of selected patients to centres with proven experience can help achieve favourable clinical outcomes.

Clinical utility of the AJCC 8th edition pT1 subclassification and impact on practice patterns in stage I seminoma.

BACKGROUND: The American Joint Committee on Cancer 8th edition staging guidelines for testicular cancer established a 3 cm cutoff to subclassify stage T1 seminomas (<3 cm = pT1a and ≥3 cm = pT1b). The efficacy of this cutoff in predicting metastatic disease and impact on treatment patterns have not been studied. METHODS: We retrospectively reviewed patients with pT1 testicular seminoma in the National Cancer Database from 2004 to 2016. Receiver operating curves were used to determine the efficacy of the 3 cm tumor cutoff in identifying metastatic disease, and multivariable regression was used to compute the effect of tumor size on the rate of adjuvant therapy among Stage I patients. RESULTS: A total of 10,134 patients with pT1 seminoma were evaluated. The current size cutoff of 3 cm for subclassification did not exhibit high discrimination in identifying metastatic disease (area under receiver operating curve: 0.546). Surveillance has grown as the preferred treatment after orchiectomy -32.1% in 2004 to 81.2% in 2015. However, the rate of adjuvant therapy for pT1, Stage I seminomas associated positively with tumor size even with adjustment for year of diagnosis. For tumors above 3 cm, the odds ratio stabilized around 1.9. By using the 3 cm cutoff to guide adjuvant therapy, up to 85% of T1b patients may be overtreated. CONCLUSION: The 3 cm cutoff for subclassification of Stage I seminoma does not predict metastatic recurrence but is associated with increased receipt of adjuvant therapy. A 3 cm cutoff and the pT1a/b classification may therefore contribute to overtreatment in many young patients with a long life expectancy for whom minimizing adverse effects should be prioritized.

Borderline serous papillary tumor of the testis.

Ovarian epithelial type tumor of the testis is a rare entity. Herein, we report borderline serous papillary tumor of the testis in a 37-year-old male, which was clinically suspected to be a testicular malignancy.

Differential expression of DNA methyltransferases and demethylases among the various testicular germ cell tumor subtypes.

Aim: Characterize DNA methyltransferases/demethylases expression in testicular germ cell tumors (TGCTs). Methods:In silico analysis of TCGA database, assessment of transcript levels of most relevant enzymes in four TGCT cell lines and validation in patient cohort (real-time quantitative polymerase chain reaction; immunohistochemistry). Results:DNMT3A, DNMT3B and TET2 were the most differentially expressed between seminomas (SEs) and nonseminomas (NSs). DNMT3B was significantly overexpressed in NS-related cell lines, and the opposite was found for TET2. Significantly higher DNMT3A/B mRNA expression was observed in NS, indicating a role for de novo methylation in reprogramming. Significantly higher TET2 protein expression was observed in SEs, suggesting active demethylation contributes for SE hypomethylated state. More differentiated histologies disclosed distinct expression patterns. Conclusion: DNA-modifying enzymes are differentially expressed between TGCT subtypes, influencing reprogramming and differentiation.

Clinical implications of the American Joint Committee on Cancer (AJCC) 8th edition update in seminoma pT1 subclassification.

BACKGROUND: Seminoma accounts for 30-50% of testicular germ cell tumors (TGCT)-the most common solid malignancy in men aged 15-35 years. The American Joint Committee on Cancer (AJCC) 8th edition (2018) created the subclassifications pT1a (tumor size < 3 cm) and pT1b (≥ 3 cm), despite not being universally recognized. Rete testis invasion (RTI) and tumor size > 4 cm are considered features associated with a higher recurrence risk, but not formally used for staging. The authors propose further understanding the subclassification's potential impact in clinical practice, by summarizing current evidence and reviewing clinical cases in their institutions. METHODS: All consecutive cases of seminoma stage I, pT1 treated in two institutions between January 2005 and December 2016 were included. Clinical data were retrieved, and variables were analyzed using SPSS. Relevant literature on the topic was reviewed. RESULTS: Seminoma pT1 was identified in 58 patients. By using newly AJCC criteria, 29 (50%) would have been staged as pT1a and 29 (50%) pT1b. Median age at diagnosis was similar (33 in pT1a vs 32 in pT1b). Median follow-up time 5.8 years. Almost half (45%) of pT1b patients had a tumor size < 4 cm. The majority of either pT1a or pT1b were treated with chemotherapy or radiotherapy, reflecting more intensive approaches in the past. Three retroperitoneal recurrences were recorded (two in pT1a, one in pT1b, all under surveillance protocol); no deaths occurred. RTI and extensive necrosis (EN) were associated with pT1b (P <  0.0001 and P = 0.023, respectively), known adverse biological features. CONCLUSIONS: In our population, the exploratory analysis of the newly created AJCC criteria showed no significant difference in recurrence or death, although pT1b was associated with adverse biomarkers, such as RTI and EN, but its clinical relevance remains incompletely understood. Our results confirm an excellent prognosis, regardless of subcategorization, thus a larger population and a longer follow-up time are needed to understand prospectively the impact of the recently updated criteria. We would recommend using the latest AJCC staging system, although the individual risk of relapse, long-term toxicities and patient preferences should be taken into account when considering surveillance or active treatment adjuvant options.

A Morphologic and Immunohistochemical Comparison of Nuclear ß-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 ß-catenin expression. We, therefore, compared the morphologic and immunohistochemical features of 18 SCTs-NOS with strong, diffuse nuclear ß-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 ß-catenin, there remain differences, both morphologically and immunohistochemically, between these neoplasms to the degree that SCT-NOS should not be equated with pancreatic SPN.

MicroRNA and transcription factor co-regulatory networks and subtype classification of seminoma and non-seminoma in testicular germ cell tumors.

Recent studies have revealed that feed-forward loops (FFLs) as regulatory motifs have synergistic roles in cellular systems and their disruption may cause diseases including cancer. FFLs may include two regulators such as transcription factors (TFs) and microRNAs (miRNAs). In this study, we extensively investigated TF and miRNA regulation pairs, their FFLs, and TF-miRNA mediated regulatory networks in two major types of testicular germ cell tumors (TGCT): seminoma (SE) and non-seminoma (NSE). Specifically, we identified differentially expressed mRNA genes and miRNAs in 103 tumors using the transcriptomic data from The Cancer Genome Atlas. Next, we determined significantly correlated TF-gene/miRNA and miRNA-gene/TF pairs with regulation direction. Subsequently, we determined 288 and 664 dysregulated TF-miRNA-gene FFLs in SE and NSE, respectively. By constructing dysregulated FFL networks, we found that many hub nodes (12 out of 30 for SE and 8 out of 32 for NSE) in the top ranked FFLs could predict subtype-classification (Random Forest classifier, average accuracy ≥90%). These hub molecules were validated by an independent dataset. Our network analysis pinpointed several SE-specific dysregulated miRNAs (miR-200c-3p, miR-25-3p, and miR-302a-3p) and genes (EPHA2, JUN, KLF4, PLXDC2, RND3, SPI1, and TIMP3) and NSE-specific dysregulated miRNAs (miR-367-3p, miR-519d-3p, and miR-96-5p) and genes (NR2F1 and NR2F2). This study is the first systematic investigation of TF and miRNA regulation and their co-regulation in two major TGCT subtypes.

Contemporary North-American population-based validation of the International Germ Cell Consensus Classification for metastatic germ cell tumors of the testis.

BACKGROUND: The International Germ Cell Consensus Classification (IGCCC) is the recommended stratification scheme for newly diagnosed metastatic seminoma (mSGCT) and non-seminoma germ cell tumor (mNSGCT) patients. However, a contemporary North-American population-based validation has never been completed and represented our focus. MATERIALS AND METHODS: We identified mSGCT and mNSGCT patients within the SEER database (2004-2015). The IGCCC criteria were used for stratification into prognostic groups. Kaplan-Meier (KM) derived actuarial 5-year overall survival (OS) rates were calculated. In addition, cumulative incidence plots tested cancer-specific (CSM) and other-cause mortality (OCM) rates. RESULTS: Of 321 mSGCT patients, 190 (59.2%) and 131 (40.8%), respectively, fulfilled good and intermediate prognosis criteria. Of 803 mNSGCT patients, 209 (26.1%), 100 (12.4%), and 494 (61.5%), respectively, fulfilled good, intermediate, and poor prognosis criteria. In mSGCT patients, actuarial KM derived 5-year OS was 87% and 78% for, respectively, good and intermediate prognosis groups (p = 0.02). In cumulative incidence analyses, statistically significant differences were recorded for CSM but not for OCM between good versus intermediate prognosis groups. In mNSGCT patients, actuarial KM derived 5-year OS was 89%, 75% and 60% for, respectively, good, intermediate, and poor prognosis groups (p < 0.001). In cumulative incidence analyses, statistically significant differences were recorded for both CSM and OCM between good, intermediate, and poor prognosis groups. CONCLUSIONS: Our findings represent the first population-based validation of the IGCCC in contemporary North-American mSGCT and mNSGCT patients. The recorded OM rates closely replicate those of the original publication, except for better survival of poor prognosis mNSGCT patients.

Ovarian germ cell tumour classification: views from the testis.

The classification of ovarian germ cell tumours has remained unchanged for many years, while there have been considerable changes in the testicular classification. In recent years there has been concern about the overtreatment of clinical stage 1 testicular germ cell tumours with increasing use of surveillance for low-risk disease. We outline here the current classification of germ cell tumours of the ovary with particular regard to treatment and outcome and highlight some areas which may cause confusion, particularly pertaining to immature teratomas and mixed germ cell tumours. We suggest that some minor changes to the classification, evidenced by a recent retrospective series by some of the authors, may lead to less adjuvant chemotherapy for immature teratomas and may obviate the need for the grading of immature teratomas, by aligning with testicular experience in pure post-pubertal teratomas. Adoption of this will require retrospective and prospective re-evaluation, but may avoid long-term patient morbidity.

Testicular Cancer, Version 2.2020, NCCN Clinical Practice Guidelines in Oncology.

Testicular cancer is relatively uncommon and accounts for <1% of all male tumors. However, it is the most common solid tumor in men between the ages of 20 and 34 years, and the global incidence has been steadily rising over the past several decades. Several risk factors for testicular cancer have been identified, including personal or family history of testicular cancer and cryptorchidism. Testicular germ cell tumors (GCTs) comprise 95% of malignant tumors arising in the testes and are categorized into 2 main histologic subtypes: seminoma and nonseminoma. Although nonseminoma is the more clinically aggressive tumor subtype, 5-year survival rates exceed 70% with current treatment options, even in patients with advanced or metastatic disease. Radical inguinal orchiectomy is the primary treatment for most patients with testicular GCTs. Postorchiectomy management is dictated by stage, histology, and risk classification; treatment options for nonseminoma include surveillance, systemic therapy, and nerve-sparing retroperitoneal lymph node dissection. Although rarely occurring, prognosis for patients with brain metastases remains poor, with >50% of patients dying within 1 year of diagnosis. This selection from the NCCN Guidelines for Testicular Cancer focuses on recommendations for the management of adult patients with nonseminomatous GCTs.

[Management of metastatic testicular germ cell tumors]. / Principes de prise en charge des tumeurs germinales testiculaires métastatiques.

Metastatic testicular germ cell tumors are rare entities with a high cure rate owing to their major chemosensitivity. Current guidelines should be strictly followed to ensure maximal cure rate. Germ cell tumor treatment requires multidisciplinary skills and is based on cisplatin-based chemotherapy. The current challenge for these patients with favorable prognosis is to limit over- or under-treatment. Centralization of care for patients with these rare cancers is a key point to achieve the best chance of cure.

[Testicular germ cell tumors: Histopathological and molecular features]. / Tumeurs germinales du testicule : caractéristiques histopathologiques et moléculaires.

In 2016, the WHO classification of testicular germ cell tumors was revised considering advances in the understanding of their tumorigenesis and molecular features. This restructuring led to a division into two major groups with, on one hand, prepubertal-type tumors, not derived from germ cell neoplasia in situ (GCNIS), and on the other hand, postpubertal-type tumors, GCNIS-derived, which occur in youg men (seminoma and non seminomatous germ cell tumors - embryonal carcinoma, yolk sac tumor, teratoma and choriocarcinoma essentially). The term germ cell neoplasia in situ is consensually accepted as a new terminology for the precursor lesion. In this new classification, the term "spermatocytic seminoma" is replaced by "spermatocytic tumor", reclassified among non-GCNIS-derived tumors. The purpose of this change of nomenclature is to reflect the usually non-aggressive behaviour of this tumor and to avoid any confusion with usual seminoma. The spectrum of trophoblastic tumors continues to expand with the description of new rare entities such as the cystic trophoblastic tumor, the placental site trophoblastic tumor and the epithelioid trophoblastic tumor. This review aims to provide a focus on testicular germ cell tumors highlighting the new immunohistochemical and molecular features responsible for the restructuring of classification. The TNM staging is presented according to the AJCC 8th edition 2017 update.

Shared and unique genomic structural variants of different histological components within testicular germ cell tumours identified with mate pair sequencing.

Post-pubertal testicular germ-cell tumours (TGCTs) can present with a variety of distinct histologies which are nevertheless lineage related and often co-occurring. The exact lineage relationships and developmental pathways leading to the different histologies is debated. In order to investigate the relationship of histologic populations, mate-pair sequencing (MPseq) and exome sequencing (ExomeSeq) were conducted on different histological populations within the same tumour. Ten TGCTs with 1-3 histologic types/tumour were sequenced. Junctions of somatic chromosomal rearrangements were identified on a per genome basis, with germ cell neoplasia in situ possessing the least (median 1, range 0-4) and embryonal carcinoma the most (median 8.5, range 6-12). Copy number variation revealed gains and losses, including isoform 12p (i12p) (10/10 samples), and chromosomes 7, 8, and 21 gains (7/10 samples). Mapping of shared junctions within a tumour revealed lineage relationships, but only i12p was shared between patients. ExomeSeq from two cases demonstrated a high level of copy-neutral loss of heterozygosity. Parallel assessment of separate histologies within a single TGCT demonstrated cumulative and divergent changes, suggesting the importance of parallel sequencing for detection of relevant biomarkers.

Reclassification of good-risk seminoma: prognostic factors, novel biomarkers and implications for clinical management.

Germ cell tumors represent 11% of the cancers diagnosed in adolescent males and are the most common solid tumors in adult men between the ages of 20 and 35. Pure seminoma accounts for around 50% of all testicular germ cell tumors. The prognostic classification of the International Germ Cell Cancer Collaborative Group for good-prognosis seminoma includes both nodal disease and pulmonary visceral metastases. In this article, we analyzed recent data on prognosis and outcome of good-prognosis seminoma to revise the traditional classification of the disease and improve tailored treatment.

Pre-orchiectomy tumor marker levels should not be used for International Germ Cell Consensus Classification (IGCCCG) risk group assignment.

PURPOSE: To investigate whether the use of pre-orchiectomy instead of pre-chemotherapy tumor marker (TM) levels has an impact on the International Germ Cell Consensus Classification (IGCCCG) risk group assignment in patients with metastatic germ cell tumors (GCT). METHODS: Demographic and clinical information of all patients treated for primary metastatic testicular non-seminomatous GCT in our tertiary care academic center were extracted from medical charts. IGCCCG risk group assignment was correctly performed with pre-chemotherapy marker levels and additionally with pre-orchiectomy marker levels. Agreement between pre-chemotherapy and pre-orchiectomy risk group assignments was assessed using Cohen's kappa. RESULTS: Our cohort consisted of 83 patients. The use of pre-orchiectomy TMs resulted in an IGCCCG risk group upstaging in 12 patients (16%, 8 patients from good to intermediate risk and 4 patients from intermediate to poor risk) and a downstaging in 1 patient (1.2%, from intermediate- to good-risk). The agreement between pre-orchiectomy and pre-chemotherapy IGCCCG risk groups resulted in a Cohen's kappa of 0.888 (p < 0.001). CONCLUSIONS: Using pre-orchiectomy TMs can result in incorrect IGCCCG risk group assignment, which in turn can impact on the clinical management and follow-up of patients with metastatic GCT. Thus, adherence to the IGCCCG standard using pre-chemotherapy TMs levels is recommended.

Recently Described and Clinically Important Entities in Testis Tumors: A Selective Review of Changes Incorporated Into the 2016 Classification of the World Health Organization.

CONTEXT.­: In 2016 the World Health Organization published a revised classification of testicular neoplasms based upon advances in understanding their pathogenesis and molecular biology. The rationale for this revision and additional clinically relevant observations were the topics of a talk given to the Houston Society of Clinical Pathologists in April 2017. This paper summarizes that talk. OBJECTIVE.­: To summarize and explain the most important changes to the classification of testicular neoplasms in the World Health Organization 2016 revision. DATA SOURCES.­: Peer-reviewed published literature and contributions by individuals with expertise in this area that were also reviewed by genitourinary pathologists. CONCLUSIONS.­: Most changes occurred in the germ cell tumor classification, including replacement of the terms intratubular germ cell neoplasia unclassified and carcinoma in situ by germ cell neoplasia in situ; subdivision of the tumors into 2 main categories, those derived from germ cell neoplasia in situ and those not derived from germ cell neoplasia in situ; distinction of germ cell neoplasia in situ from germ cells with delayed maturation and pre-germ cell neoplasia in situ; expansion of the trophoblastic tumor category to include epithelioid trophoblastic tumor and cystic trophoblastic tumor; and substitution of spermatocytic tumor for spermatocytic seminoma and its placement in the non-germ cell neoplasia in situ group. Other revisions included eliminating sclerosing Sertoli cell tumor as a distinct entity; the recognition of intratubular hyalinizing Sertoli cell tumor; and acceptance of the role of undifferentiated gonadal tissue in the pathogenesis of gonadoblastoma.