Familial testicular germ cell tumors in adults: 2010 summary of genetic risk factors and clinical phenotype

New insights on testicular cancer prevalence with novel diagnostic biomarkers and therapeutic approaches

BACKGROUND

Testicular cancer (TC), comprising merely 1% of male neoplasms, holds the distinction of being the most commonly encountered neoplasm among young males.

RECENT FINDINGS

Most cases of testicular neoplasms can be classified into two main groups, namely germ cell tumors representing approximately 95% of the cases, and sex cord-stromal tumors accounting for about 5% of the cases. Moreover, its prevalence is on the rise across the globe. TC is a neoplastic condition characterized by a favorable prognosis. The advent of cisplatin-based chemotherapeutic agents in the latter part of the 1970s has led to a significant enhancement in the 5-year survival rate, which presently surpasses 95%. Given that TC is commonly detected before reaching the age of 40, it can be anticipated that these individuals will enjoy an additional 40-50 years of life following successful treatment. The potential causes of TC are multifactorial and related to different pathologies. Accurate identification is imperative to guarantee the utmost efficacious and suitable therapy. To a certain degree, this can be accomplished through the utilization of blood examinations for neoplastic indicators; nonetheless, an unequivocal diagnosis necessitates an evaluation of the histological composition of a specimen via a pathologist.

CONCLUSION

TC is multifactorial and has various pathologies, therefore this review aimed to revise the prenatal and postnatal causes as well as novel diagnostic biomarkers and the therapeutic strategies of TC.

Testicular cancer in 2023: Current status and recent progress

Testicular germ cell tumor (GCT) is the most common solid tumor in adolescent and young adult men. Progress in the management of GCT has been made in the last 50 years, with a substantial improvement in cure rates for advanced disease, from 25% in the 1970s to nearly 80%. However, relapsed or platinum-refractory disease occurs in a proportion, 20% of whom will die from disease progression. This article reviews the current evidence-based treatments for extracranial GCT, the acute and chronic toxic effects that may result, and highlights contemporary advances and progress in the field.

The environment and male reproductive system: the potential role and underlying mechanisms of cadmium in testis cancer

Cadmium is a known human carcinogen, and has been shown to profoundly affect male reproductive function, at multiple levels, by exerting both endocrine and non-endocrine actions. Nevertheless, the potential role of cadmium in the etiology of testis cancer has been scantly investigated in humans, and, currently, available epidemiological observational studies are insufficient to draw definitive conclusions in this regard. On the contrary, experimental studies in laboratory animals demonstrated that cadmium is a strong inducer of testis tumors, mostly represented by benign Leydig cell adenoma; moreover, malignant transformation was also reported in few animals, following cadmium treatment. Early experimental studies in animals proposed an endocrine-dependent mechanism of cadmium-induced testis tumorigenesis; however, more recent findings from cell-free assays, in vitro studies, and short-term in vivo studies, highlighted that cadmium might also contribute to testis tumor development by early occurring endocrine-independent mechanisms, which include aberrant gene expression within the testis, and genotoxic effects, and take place well before the timing of testis tumorigenesis. These endocrine-independent mechanisms, however, have not been directly investigated on testis tumor samples retrieved from affected, cadmium-treated animals so far. The present review focuses on the relationship between cadmium exposure and testis cancer, by reporting the few epidemiological observational human studies available, and by providing animal-based experimental evidences of cadmium implication in the pathogenesis and progression of testis tumor. Moreover, the relevance of experimental animal studies to human cadmium exposure and the translational potential of experimental findings will be extensively discussed, by critically addressing strengths and weaknesses of available data.

Risk Factors for Testicular Cancer: Environment, Genes and Infections-Is It All?

The incidence of testicular cancer is steadily increasing over the past several decades in different developed countries. If on one side better diagnosis and treatment have shone a light on this disease, on the other side, differently from other malignant diseases, few risk factors have been identified. The reasons for the increase in testicular cancer are however unknown while risk factors are still poorly understood. Several studies have suggested that exposure to various factors in adolescence as well as in adulthood could be linked to the development of testicular cancer. Nevertheless, the role of environment, infections, and occupational exposure are undoubtedly associated with an increase or a decrease in this risk. The aim of this narrative review is to summarize the most recent evidence regarding the risk factors associated with testicular cancer, starting from the most commonly evaluated (cryptorchidism, family history, infections) to the newer identified and hypothesized risk factors.

Long Noncoding RNA LINC00467: Role in Various Human Cancers

Intricate genetic mutations promote the progression of different cancer types. Long noncoding RNAs (lncRNAs) have been widely demonstrated to participate in the genomic activities of various human cancers. Long intergenic non-coding RNA 467 (LINC00467) is an upregulated lncRNA in diverse diseases, especially in several types of cancers. Functional experiments of LINC00467 revealed that LINC00467 overexpression enhanced cell chemoresistance, proliferation, migration, and invasion in several types of cancers. Moreover, overexpressed LINC00467 was associated with a poor clinical prognosis. The present evidence suggests that LINC00467 may serve as a promising prognostic indicator and become a novel cancer therapeutic target. In this review, we introduce the biologic functions of lncRNAs and describe the molecular mechanism and clinical significance of LINC00467 in detail.

Synchronous Testicular Cancer in Monozygotic Twins

Testicular cancer is the most common neoplasm in men aged 15-45 years old, with several established risk factors such as cryptorchidism, age, and family history. We report a case of a 44-year-old man with a history of cryptorchidism who presented with lesions in his right testis, a large retroperitoneal mass, and diffuse nodal lesions in his lungs. He underwent radical orchiectomy that showed testicular cancer and was immediately inducted into systemic therapy based on bleomycin, etoposide, and cisplatin. Two weeks later, his monozygotic twin brother, also reporting cryptorchidism at a young age, presented with a painless mass in his left testis. He underwent radical orchiectomy that revealed testicular cancer and received adjuvant chemotherapy. The first patient, after two cycles of chemotherapy, suffered from an episode of massive hematochezia and died while his brother remains relapse-free.

Mediterranean Diet as a Shield against Male Infertility and Cancer Risk Induced by Environmental Pollutants: A Focus on Flavonoids

The role of environmental factors in influencing health status is well documented. Heavy metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls, dioxins, pesticides, ultrafine particles, produced by human activities put a strain on the body’s entire defense system. Therefore, together with public health measures, evidence-based individual resilience measures are necessary to mitigate cancer risk under environmental stress and to prevent reproductive dysfunction and non-communicable diseases; this is especially relevant for workers occupationally exposed to pollutants and/or populations residing in highly polluted areas. The Mediterranean diet is characterized by a high intake of fruits and vegetables rich in flavonoids, that can promote the elimination of pollutants in tissues and fluids and/or mitigate their effects through different mechanisms. In this review, we collected evidence from pre-clinical and clinical studies showing that the impairment of male fertility and gonadal development, as well as cancers of reproductive system, due to the exposure of organic and inorganic pollutants, may be counteracted by flavonoids.

The cAMP-signaling cancers: Clinically-divergent disorders with a common central pathway

The cAMP-signaling cancers, which are defined by functionally-significant somatic mutations in one or more elements of the cAMP signaling pathway, have an unexpectedly wide range of cell origins, clinical manifestations, and potential therapeutic options. Mutations in at least 9 cAMP signaling pathway genes (TSHR, GPR101, GNAS, PDE8B, PDE11A, PRKARA1, PRKACA, PRKACB, and CREB) have been identified as driver mutations in human cancer. Although all cAMP-signaling pathway cancers are driven by mutation(s) that impinge on a single signaling pathway, the ultimate tumor phenotype reflects interactions between five critical variables: (1) the precise gene(s) that undergo mutation in each specific tumor type; (2) the effects of specific allele(s) in any given gene; (3) mutations in modifier genes (mutational "context"); (4) the tissue-specific expression of various cAMP signaling pathway elements in the tumor stem cell; and (5) and the precise biochemical regulation of the pathway components in tumor cells. These varying oncogenic mechanisms reveal novel and important targets for drug discovery. There is considerable diversity in the "druggability" of cAMP-signaling components, with some elements (GPCRs, cAMP-specific phosphodiesterases and kinases) appearing to be prime drug candidates, while other elements (transcription factors, protein-protein interactions) are currently refractory to robust drug-development efforts. Further refinement of the precise driver mutations in individual tumors will be essential for directing priorities in drug discovery efforts that target these mutations.

A call to action: Antiracist patient engagement in adolescent and young adult oncology research and advocacy

Amidst the concurrent global crises of coronavirus disease 2019 (COVID-19), uprisings against Anti-Black racism and police brutality, as well as anti-Asian racism and violence, the field of medicine found itself simultaneously called upon to respond as essential workers in the public health devastation of COVID-19, and as representatives of healthcare institutions wrought with the impacts of systemic racism. Clinicians, researchers, and advocates in adolescent and young adult (AYA) oncology, must come together in authentic activism to begin the work of creating structural change to advance antiracist approaches to patient engagement in AYA oncology research and advocacy. Critical review of existing practices is needed to ensure that ethical and effective research methods are employed when engaging with racial and ethnic minority AYA patients with cancer, who may be particularly vulnerable and exploited in the current context.

PDE11A gene polymorphism in testicular cancer: sperm parameters and hormonal profile

PURPOSE

Testicular germ cell tumours (TGCTs) is the most common malignancy among young adult males. The etiology is multifactorial and both environmental and genetic factors play an important role in the origin and development of TGCT. Genetic susceptibility may result from the interaction of multiple common and low-penetrance genetic variants and one of the main candidate genes is PDE11A. Many PDE11A polymorphisms were found responsible for a reduced PDE activity in TGCT patients, who often also display impaired hormone and sperm profile. The aim of this study was to investigate testicular function and PDE11A sequence in testicular cancer cases.

METHODS

Semen analysis was performed in 116 patients with unilateral and bilateral sporadic TGCTs and in 120 cancer-free controls. We also investigated hormone profile and PDE11A polymorphisms using peripheral blood samples.

RESULTS

Our data revealed that TGCT patients showed lower testosterone levels, higher gonadotropins levels and worse semen quality than controls, although the mean and the medians of sperm parameters are within the reference limits. PDE11A sequencing detected ten polymorphisms not yet associated with TGCTs before. Among these, G223A in homozygosity and A288G in heterozygosity were significantly associated with a lower risk of testicular tumour and they displayed a positive correlation with total sperm number.

CONCLUSIONS

Our findings highlight the key role of PDE11A in testis and suggest the presence of an underlying complex and fine molecular mechanism which controls testis-specific gene expression and susceptibility to testicular cancer.

Integrated analysis of high-throughput sequencing data reveals the key role of LINC00467 in the invasion and metastasis of testicular germ cell tumors

Long noncoding RNAs (lncRNAs) are involved in various physiological and pathological processes. However, the role of lncRNAs in testicular germ cell tumor (TGCT) has been rarely reported. Our purpose is to comprehensively survey the expression and function of lncRNAs in TGCT. In this study, we used RNA sequencing to construct the lncRNA expression profiles of 13 TGCT tissues and 4 paraneoplastic tissues to explore the function of lncRNAs in TGCT. The bioinformatics analysis showed that many lncRNAs are differentially expressed in TGCT. GO and KEGG enrichment analyses revealed that the differentially expressed lncRNAs participated in various biological processes associated with tumorigenesis in cis and trans manners. Further, we found that the expression of LINC00467 was positively correlated with the poor prognosis and pathological grade of TGCT using WGCNA analysis and GEPIA database data mining. In vitro experiments revealed that LNC00467 could promote the migration and invasion of TGCT cells by regulating the expression of AKT3 and influencing total AKT phosphorylation. Further analysis of TCGA data revealed that the expression was negatively correlated with the infiltration of immune cells and the response to PD1 immunotherapy. In summary, this study is the first to construct the expression profile of lncRNAs in TGCT. It is also the first study to identify the metastasis-promoting role of LNC00467, which can be used as a potential predictor of TGCT prognosis and immunotherapeutic response to provide a clinical reference for the treatment and diagnosis of TGCT metastasis.

Dataset of testicular germ cell tumors (TGCT) risk associated with serum polychlorinated biphenyl (PCB) by age at diagnosis and histologic types

In a population-based case control study of testicular germ cell tumors (TGCT), we reported a strong positive association between serum levels of Wolff's Group 1 (potentially estrogenic) polychlorinated biphenyl (PCBs) and risk of TGCT, and the observed associations were similar for both seminoma and non-seminoma. While the observed specific associations between TGCT and Wolff's Group 1 PCBs cannot be easily explained by bias or confounding, a question can still be asked, that is, could the relationship between PCBs and TGCT differ by age at diagnosis? PCBs tend to bioaccumulate, with more heavily chlorinated PCB congeners tending to have longer half-lives. Half-lives of PCB congeners were reported ranging from 4.6 years for PCB-28 to 41.0 years for PCB-156. The half-life for the heavy PCB congeners (17.8 years) was found to be approximately twice that for the light PCBs (9.6 years) in early studies. Therefore, the same PCB concentration measured in a 20-year-old vs. a 55-year-old is unlikely to represent the same lifetime PCB exposure or type of PCB exposure. In this analysis, we stratified the data by median age of diagnosis of TGCT and further stratified by histologic type of TGCT (seminoma vs non-seminoma) to explore if the risk of TGCT associated with PCB exposures differs by age.

Histological Features of Sporadic and Familial Testicular Germ Cell Tumors Compared and Analysis of Age-Related Changes of Histology

Simple Summary

Testicular germ cell tumors (TGCT) are highly heritable, and earlier studies reported a higher prevalence of certain microscopic features in familial cases compared with sporadic cases. Reasoning by analogy relative to different causal genes for different histologic subtypes of familial kidney cancer, we searched for etiologically informative histopathology associations in familial testicular germ cell cancer. We conducted a detailed, blinded pathology review of familial and sporadic TGCT cases to investigate whether we could identify differences between these two patient subsets and to study the effect of age at diagnosis on histologic features in both groups combined. Our results show no specific histologic differences between familial and sporadic TGCTs. However, we observed histologic features that varied with age at diagnosis among the two groups combined. Thus, our results suggest that there are no histological differences between familial and sporadic TGCT that might identify genetically distinct disease subsets.

Abstract

This study aimed to compare histological features of familial and sporadic testicular germ cell tumors (TGCTs) and surrounding parenchyma, since discriminating features might be etiologically relevant and clinically useful. The study of parenchyma was prompted by reports claiming a higher prevalence of testicular microlithiasis in familial cases. Histological features of TGCTs and surrounding parenchyma of 296 sporadic and 305 familial cases were compared. For each case, one representative hematoxylin and eosin-stained slide was available. Slides were independently scored by two expert pathologists using a semi-quantitative data abstract. Discrepancies were resolved by consensus. A logistic regression model was used to assess the ability to discriminate between sporadic and familial GCT. The histological composition of a tumor, amount of lymphocytic infiltration, amount of germ cell neoplasia in situ (GCNIS), and presence of testicular microlithiasis (TM) did not discriminate between sporadic and familial GCT (area under the curve 0.56, 95%CI 0.51–0.61). Novel observations included increasing lymphocytic infiltration and decreasing GCNIS and TM with increasing age at diagnosis. The presence of tubules with infiltrating lymphocytes was mainly associated with pure seminomas and nonseminomas with a seminoma component. Among seminomas, tubules with infiltrating lymphocytes decreased with increasing age. No discernable differences between sporadic and familial TGCTs were found. The age-related changes in the tumors and surrounding parenchyma in these groups combined are consistent with a host response building up over time predominantly affecting seminomas, the seminoma-component of nonseminomas and GCNIS. TM may gradually dissolve with age. Our hypothesis that histological differences between sporadic and familial TGCT might identify genetically distinct disease subsets was not supported.

RNA-Binding Proteins Play an Important Role in the Prognosis of Patients With Testicular Germ Cell Tumor

Testicular germ cell tumors (TGCTs) are common urological neoplasms in young adult males. The outcome of TGCT depends on pathologic type and tumor stage. RNA-binding proteins (RBPs) influence numerous cancers via post-transcriptional regulation. The prognostic importance of RBPs in TGCT has not been fully investigated. In this study, we set up a prognostic risk model of TGCT using six significantly differentially expressed RBPs, namely, TRMT61A, POLR2J, DIS3L2, IFIH1, IGHMBP2, and NPM2. The expression profiles were downloaded from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression datasets. We observed by performing least absolute shrinkage and selection operator (LASSO) regression analyses that in the training cohort, the expression of six RBPs was correlated with disease-free survival in patients with TGCT. We assessed the specificity and sensitivity of 1-, 3-, 5-, and 10-year survival status prediction using receiver operating characteristic curve analysis and successfully validated using the test cohorts, the entire TCGA cohort, and Gene Expression Omnibus (GEO) datasets. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and gene set enrichment analyses were carried out to seek the possible signaling pathways related with risk score. We also examined the association between the model based on six RBPs and different clinical characteristics. A nomogram was established for TGCT recurrence prediction. Consensus clustering analysis was carried out to identify the clusters of TGCT with different clinical outcomes. Ultimately, external validations of the six-gene risk score were performed by using the GSE3218 and GSE10783 datasets downloaded from the GEO database. In general, our study constructed a prognostic model based on six RBPs, which could serve as independent risk factor in TGCT, especially in seminoma, and might have brilliant clinical application value.

Serum polychlorinated biphenyl (PCB) levels and risk of testicular germ cell tumors: A population-based case-control study in Connecticut and Massachusetts

The incidence rate of testicular germ cell tumors (TGCT) has continuously increased in Western countries over the last several decades. Some epidemiologic studies have reported that the endocrine disrupting polychlorinated biphenyls (PCBs) in serum may be associated with TGCT risk, but the evidence is inconsistent. Our goal was to investigate whether serum levels of PCBs are associated with the increase of TGCT risk. We conducted a population-based case-control study of 308 TGCT cases and 323 controls, all residents of Connecticut and Massachusetts. Serum levels of 56 PCBs congeners were measured using gas chromatography and unconditional logistic regression model was used to evaluate the risk of TGCT associated with total PCBs exposure, groups of PCBs categorized by Wolff's functional groups, and individual PCB congeners. The results showed that there was no association between total serum levels of PCBs and risk of TGCT overall (quartile 4 (Q4) vs. quartile 1 (Q1) odds ratio (OR) and 95% confidence interval (C.I.) = 1.0 (0.6-1.9), ρ trend = 0.9). However, strong positive association was observed between total serum levels of Wolff's Group 1 (potentially estrogenic) PCBs and risk of overall TGCT (Q4 vs. Q1 OR = 2.5, 95% CI = 1.3-4.7, ρ trend <0.05) as well as seminoma and non-seminoma subtypes. Wolff's Group 1 PCB congeners that showed an increased risk of TGCT included: 25, 44, 49, 52, 70, 101, 174, and 201/177. Considering the continuing increase of TGCT, these associations should be replicated in different populations with larger sample size.

Cancer statistics for adolescents and young adults, 2020

Cancer statistics for adolescents and young adults (AYAs) (aged 15-39 years) are often presented in aggregate, masking important heterogeneity. The authors analyzed population-based cancer incidence and mortality for AYAs in the United States by age group (ages 15-19, 20-29, and 30-39 years), sex, and race/ethnicity. In 2020, there will be approximately 89,500 new cancer cases and 9270 cancer deaths in AYAs. Overall cancer incidence increased in all AYA age groups during the most recent decade (2007-2016), largely driven by thyroid cancer, which rose by approximately 3% annually among those aged 20 to 39 years and 4% among those aged 15 to 19 years. Incidence also increased in most age groups for several cancers linked to obesity, including kidney (3% annually across all age groups), uterine corpus (3% in the group aged 20-39 years), and colorectum (0.9%-1.5% in the group aged 20-39 years). Rates declined dramatically for melanoma in the group aged 15 to 29 years (4%-6% annually) but remained stable among those aged 30 to 39 years. Overall cancer mortality declined during 2008 through 2017 by 1% annually across age and sex groups, except for women aged 30 to 39 years, among whom rates were stable because of a flattening of declines in female breast cancer. Rates increased for cancers of the colorectum and uterine corpus in the group aged 30 to 39 years, mirroring incidence trends. Five-year relative survival in AYAs is similar across age groups for all cancers combined (range, 83%-86%) but varies widely for some cancers, such as acute lymphocytic leukemia (74% in the group aged 15-19 years vs 51% in the group aged 30-39 years) and brain tumors (77% vs 66%), reflecting differences in histologic subtype distribution and treatment. Progress in reducing cancer morbidity and mortality among AYAs could be addressed through more equitable access to health care, increasing clinical trial enrollment, expanding research, and greater alertness among clinicians and patients for early symptoms and signs of cancer. Further progress could be accelerated with increased disaggregation by age in research on surveillance, etiology, basic biology, and survivorship.

Lack of pathogenic germline DICER1 variants in males with testicular germ-cell tumors

BACKGROUND

Several studies have reported conflicting evidence on the inclusion of testicular germ cell tumors (TGCT) in the DICER1 tumor-predisposition phenotype. We evaluated the relationship between DICER1 and TGCT by reviewing scrotal ultrasounds of males with pathogenic germline variants in DICER1 and queried exome data from TGCT-affected men for DICER1 variants.

METHODOLOGY

Fifty-four male DICER1-carriers and family controls (n=41) enrolled in the National Cancer Institute (NCI) DICER1 Natural History Study were offered scrotal ultrasounds. These studies were examined by a single radiologist for abnormalities. In parallel, DICER1 variants from two large exome-sequenced TGCT cohorts were extracted. We used previously published AMG-AMP criteria to characterize rare DICER1 variants.

RESULTS

There was no observed difference in frequency of testicular cystic structures in DICER1-carriers versus controls. DICER1 variation was not associated with TGCT in the NCI DICER1-carriers. In 1,264 exome-sequenced men with TGCT, none harbored ClinVar- or InterVar-determined pathogenic or likely pathogenic variants in DICER1. Three DICER1 variants of uncertain significance (one case and two controls) were predicted "damaging" based on a priori criteria.

CONCLUSION

Using two complementary approaches, we found no evidence of an association between pathogenic DICER1 variants and TGCT.

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.

SPANXN2 functions a cell migration inhibitor in testicular germ cell tumor cells

Background

SPANX family members are thought to play an important role in cancer progression. The SPANXN2 is a gene expressed mainly in normal testis, but its role in testicular germ cell tumors (TGCTs) has yet to be investigated. TGCT is one of the most common solid tumors in young men and is associated with poor prognosis; however, effective prognostic indicators remain elusive. Therefore, we investigated the role of SPANXN2 in TGCT development.

Methods

SPANXN2 expression levels were validated by quantitative real-time polymerase chain reaction (qRT-PCR) analyses of 14 TGCT samples and five adjacent normal tissue samples. SPANXN2 was transiently overexpressed in TGCT cells to study the consequences for cell function. The effects of SPANXN2 on cell migration were evaluated in transwell and wound healing assays. The effects on cloning ability were evaluated in colony formation assays. MTT assays and cell cycle analysis were used to detect the effects of SPANXN2 on cell proliferation. The expression levels of EMT- and AKT-related proteins in cells overexpressing SPANXN2 were analyzed by Western blotting.

Results

Compared with adjacent normal tissues, the Gene Expression Profiling Interactive Analysis database showed SPANXN2 expression was downregulated in TGCTs which was consistent with the qRT-PCR analysis. SPANXN2 overexpression reduced cell migration and colony formation capability and downregulated expression of EMT- and AKT-related proteins, Vimentin, Snail, AKT, and p-AKT.

Conclusion

Our results suggest that SPANXN2 regulates TGCT cell migration via EMT- and AKT-related proteins although its role in the occurrence and development of TGCT remains to be fully elucidated.

Estimates of over-time trends in incidence and mortality of testicular cancer from 1990 to 2030

Background

This study aims to explore and project the temporal trends in incidence and mortality of testicular cancer. Moreover, it can provide theoretical guidance for the rational allocation of health resources.

Methods

This study analyzed existing data on testicular cancer morbidity and mortality from 1990 to 2016 and predicted time-varying trends of age-standardized incidence rate (ASIR) and age-standardized death rate (ASDR) from 2017 to 2030 in different ages, regions and sociodemographic index (SDI) quintile sub-groups.

Result

Globally, numbers of testicular cancer cases in 2016 [66,833; 95% uncertainty interval (UI), 64,487–69,736] are 1.8 times larger than in 1990 (37,231; 95% UI, 36,116–38,515). The testicular cancer-related death cases increased slightly from 8,394 (95% UI, 7,980–8,904) in 1990 to 8,651 (95% UI, 8,292–9,027) in 2016. In aspect of ASIR, the data showed an up-trend from 0.74 (95% UI, 0.72–0.77) in 1990 to 0.88 (95% UI, 0.85–0.92) in 2016. The ASDR of testicular cancer declined from 0.18 (95% UI, 0.17–0.19) in 1990 to 0.12 (95% UI, 0.11–0.12) in 2016. From 2017 to 2030, predictions of trends in testicular cancer indicate that the ASIRs of most SDI countries are rising, but the ASDRs trends in testicular cancer will decrease.

Conclusions

By analyzing the available and reliable data in different ages, regions and SDI, this study shows a significant upward trend in incidence and a slow upward trend in mortality of testicular cancer from 1990 to 2016, and simultaneously, predicts the increase of ASIR and the downward trend of ASDR in 2017–2030.

Contemporary management of early stage testicular seminoma

Therapy for early stage testicular seminoma has changed radically over the past several decades. Given high cure rates and clinical trials supporting less active therapy in most cases, close observation after radical orchiectomy is now considered standard of care for clinical stage (CS) IA/IB seminoma, with either radiation therapy (RT) or chemotherapy salvage options possible. For CS IIA/IIB seminoma characterized by non-bulky retroperitoneal lymph node involvement (≤5 cm in greatest dimension), RT or combination chemotherapy are the standard of care. Given high comparable survival rates, preventing treatment-related toxicity and second malignancy, and limiting quality of life deficits associated with intense treatment has gained much greater importance. Clinical trials are currently testing the feasibility of retroperitoneal lymph node dissection (RPLND) for low volume CS IIA/IIB metastatic testicular seminoma to this end. Likewise, one cycle of chemotherapy is being evaluated as an adjuvant approach to reduce recurrence rates in CS I disease with unfavorable risk factors. Moreover, recent genomic and molecular studies have recently identified novel signatures and a potential biomarker for testicular seminoma. In this review, we first summarize the evolution of early stage seminoma management and discuss the effectiveness and drawbacks of contemporary treatment strategies. We further outline future perspectives and potential challenges in management of early stage testicular seminoma.

Systemic therapy for primary and extragonadal germ cell tumors: prognosis and nuances of treatment

Testicular germ cell tumors are the most common solid tumors in young men. These cancers represent a success story of modern medicine in our ability to cure young patients and offer decades of life, with a 5-year survival rate of approximately 95%. This review outlines the staging and risk classification of testicular cancers, and reviews the current state of knowledge and standard of care for the systemic treatment of testicular germ cell tumors with chemotherapy, focusing on the relevant clinical data supporting each treatment regimen. This review also briefly highlights current areas of active investigation, notably in the relapsed and refractory setting, including ongoing clinical trials.

Association between risk factors and testicular microlithiasis

Background

Testicular microlithiasis and its clinical significance are not fully understood. Testicular microlithiasis and risk factors have been associated with testicular cancer. The role of testicular microlithiasis is investigated.

Purpose

To investigate the association between testicular microlithiasis and socioeconomic and other pre-diagnostic factors.

Material and Methods

All men who had a scrotal ultrasound examination at the Department of Radiology, Vejle Hospital, during 2001–2013 were included. They were categorized as patients with and without testicular microlithiasis and compared with pre-diagnostic data from a nationwide registry. A total of 2404 men (283 [11.8%] with testicular microlithiasis and 2121 [88.2%] without testicular microlithiasis) were included. The association between testicular microlithiasis and pre-diagnostic conditions was investigated with logistic regression.

Results

Overall, we found no statistically significant differences in demographics, socioeconomic characteristics, or testicular diseases in men with and without testicular microlithiasis. Men with testicular microlithiasis had more often been treated for infertility (odds ratio [OR] 2.09, 95% confidence interval [CI] 0.84–5.24) and testicular torsion (OR 1.58, 95% CI 0.34–7.36) compared to men without testicular microlithiasis. We found no association between sexually transmitted diseases and testicular microlithiasis.

Conclusion

Treatment for infertility and torsion was non-significantly associated with testicular microlithiasis and no other association was found. These data do not suggest early exposure is related to testicular microlithiasis.

A Role for Phosphodiesterase 11A (PDE11A) in the Formation of Social Memories and the Stabilization of Mood

The most recently discovered 3',5'-cyclic nucleotide phosphodiesterase family is the Phosphodiesterase 11 (PDE11) family, which is encoded by a single gene PDE11A. PDE11A is a dual-specific PDE, breaking down both cAMP and cGMP. There are four PDE11A splice variants (PDE11A1-4) with distinct tissue expression profiles and unique N-terminal regulatory regions, suggesting that each isoform could be individually targeted with a small molecule or biologic. PDE11A4 is the PDE11A isoform expressed in brain and is found in the hippocampal formation of humans and rodents. Studies in rodents show that PDE11A4 mRNA expression in brain is, in fact, restricted to the hippocampal formation (CA1, possibly CA2, subiculum, and the adjacently connected amygdalohippocampal area). Within the hippocampal formation of rodents, PDE11A4 protein is expressed in neurons but not astrocytes, with a distribution across nuclear, cytoplasmic, and membrane compartments. This subcellular localization of PDE11A4 is altered in response to social experience in mouse, and in vitro studies show the compartmentalization of PDE11A4 is controlled, at least in part, by homodimerization and N-terminal phosphorylation. PDE11A4 expression dramatically increases in the hippocampus with age in the rodent hippocampus, from early postnatal life to late aging, suggesting PDE11A4 function may evolve across the lifespan. Interestingly, PDE11A4 protein shows a three to tenfold enrichment in the rodent ventral hippocampal formation (VHIPP; a.k.a. anterior in primates) versus dorsal hippocampal formation (DHIPP). Consistent with this enrichment in VHIPP, studies in knockout mice show that PDE11A regulates the formation of social memories and the stabilization of mood and is a critical mechanism by which social experience feeds back to modify the brain and subsequent social behaviors. PDE11A4 likely controls behavior by regulating hippocampal glutamatergic, oxytocin, and cytokine signaling, as well as protein translation. Given its unique tissue distribution and relatively selective effects on behavior, PDE11A may represent a novel therapeutic target for neuropsychiatric, neurodevelopmental, or age-related disorders. Therapeutically targeting PDE11A4 may be a way to selectively restore aberrant cyclic nucleotide signaling in the hippocampal formation while leaving the rest of the brain and periphery untouched, thus, relieving deficits while avoiding unwanted side effects.

Testicular cancer in two brothers of a quadruplet: a case report and a review of literature

Introduction. Testicular cancer and a multiple birth are both rare events, and the risk of testicular cancer is increased in twins. In Lithuania, only five quadruplets have been recorded since the middle of the 20th century. In this report, we present two rare events in one family: testicular cancer in two brothers of a quadruplet (three brothers and a sister). Case description. Both patients were diagnosed at 21 years of age and died within two years from the diagnosis despite treatment. The third symptomless brother did not have testicular pathology. We also review the risk factors associated with testicular cancer, and the proposed hypotheses how a multiple birth results in an increased risk. The most consistent risk factors for testicular cancer are cryptorchidism, prior history of testicular cancer, and a positive familial history. According to different studies, the risk of testicular cancer in twins is higher from 22% to 30%, compared to the general population. Conclusions. To our knowledge, we have presented the first case of testicular teratoblastoma in brothers of a quadruplet.

Epidemiological trends of hormone-related cancers in Slovenia

The incidence of hormone-related cancers tends to be higher in the developed world than in other countries. In Slovenia, six hormone-related cancers (breast, ovarian, endometrial, prostate, testicular, and thyroid) account for a quarter of all cancers. Their incidence goes up each year, breast and prostate cancer in particular. The age at diagnosis is not decreasing for any of the analysed cancer types. The risk of breast cancer is higher in the western part of the country, but no differences in geographical distribution have been observed for other hormone-related cancers. Furthermore, areas polluted with endocrine-disrupting chemicals that affect hormone balance such as PCBs, dioxins, heavy metals, and pesticides, do not seem to involve a greater cancer risk. We know little about how many cancers can be associated with endocrine disruptors, as there are too few reliable exposure studies to support an association.

Parent-of-origin effects of A1CF and AGO2 on testicular germ-cell tumors, testicular abnormalities, and fertilization bias

Testicular tumors, the most common cancer in young men, arise from abnormalities in germ cells during fetal development. Unconventional inheritance for testicular germ cell tumor (TGCT) risk both in humans and mice implicates epigenetic mechanisms. Apolipoprotein B mRNA-editing enzyme complex 1 (APOBEC1) cytidine deaminase and Deadend-1, which are involved in C-to-U RNA editing and microRNA-dependent mRNA silencing, respectively, are potent epigenetic modifiers of TGCT susceptibility in the genetically predisposed 129/Sv inbred mouse strain. Here, we show that partial loss of either APOBEC1 complementation factor (A1CF), the RNA-binding cofactor of APOBEC1 in RNA editing, or Argonaute 2 (AGO2), a key factor in the biogenesis of certain noncoding RNAs, modulates risk for TGCTs and testicular abnormalities in both parent-of-origin and conventional genetic manners. In addition, non-Mendelian inheritance was found among progeny of A1cf and Ago2 mutant intercrosses but not in backcrosses and without fetal loss. Together these findings suggest nonrandom union of gametes rather than meiotic drive or preferential lethality. Finally, this survey also suggested that A1CF contributes to long-term reproductive performance. These results directly implicate the RNA-binding proteins A1CF and AGO2 in the epigenetic control of germ-cell fate, urogenital development, and gamete functions.

MGMT and CALCA promoter methylation are associated with poor prognosis in testicular germ cell tumor patients

Testicular germ cell tumors (TGCT) represent the second main cause of cancer-related death in young men. Despite high cure rates, refractory disease results in poor prognosis. Epigenetic reprogramming occurs during the development of seminomas and non-seminomas. Understanding the molecular and genetic basis of these tumors would represent an important advance in the search for new TGCT molecular markers. Hence the frequency of methylation of a gene panel (VGF, MGMT, ADAMTS1, CALCA, HOXA9, CDKN2B, CDO1 and NANOG) was evaluated in 72 primary TGCT by quantitative methylation specific PCR. A high frequency of MGMT (90.9%, 20/22; p=0.019) and CALCA (90.5%, 19/21; p<0.026) methylation was associated with non-seminomatous tumors while CALCA methylation was also associated with refractory disease (47.4%, 09/19; p=0.005). Moreover, promoter methylation of both genes predicts poor clinical outcome for TGCT patients (5-year EFS: 50.5% vs 77.1%; p=0.032 for MGMT and 51.3% vs 77.0%; p=0.029 for CALCA). The findings of this study indicate that methylation of MGMT and CALCA are frequent and could be used as new molecular markers of prognosis in TGCT.

Testicular germ cell tumor: Short and long-term side effects of treatment among survivors

Long-term prognosis of germ cell tumor (GCT) types is excellent, however, treatment is associated with non-negligible complication rates and a negative impact on quality of life. The present study described treatment results in terms of survival, both short and long-term toxicity, and paternity rates in a cohort of patients treated at Jules Bordet Institute, University ULB of Brussels (Brussels, Belgium). The present study analyzed the data of a cohort of patients with GCT types. Pre-operative patient and tumor characteristics were described. Performance status, pulmonary function tests and renal clearance prior to chemotherapy were noted. Chemotherapeutic regimens and their associated toxicities were analyzed. The duration to event-free, cancer-specific and overall survivals were estimated using Kaplan-Meier curves. A total of 115 patients (median age, 31-years-old) were treated for a GCT at Jules Bordet Institute. At a median follow-up of 6-years, 11 (10%) patients had relapsed and 2 (2%) developed a second malignant neoplasm. At the final follow-up, 97 (89%) and 6 (5.5%) patients exhibited complete and partial remission, respectively. A total of 6% of patients exhibited a progressive disease. In terms of short-term toxicity, 11% of patients presented with febrile neutropenia. The 10-year overall survival rate and relapse-free survival rate were 93.4 and 89.8%, respectively. The paternity rate post-treatment was 27%. Testicular GCT survivors suffered from short- and long-term treatment-associated side effects on both a physical and psychological level. A long-term close follow-up is necessary in order to assist the patient with these treatment-induced complications.

Testicular seminoma metastasis to duodenum. Misdiagnosed as primary duodenal tumor

INTRODUCTION

Testicular cancer is the most common malignancy in Males aged 15-35 years. Its incidence comprises 0.8% of all Male cancers worldwide, with a mortality rate of 0.1%. Rarely it metastasizes to the retroperitoneum and invades upper gastrointestinal tract (GIT). Complications like intestinal obstruction, hemorrhage, and perforation are usually present.

PRESENTATION OF CASE

We report a 30 year-old male, presented to GIT unit with severe anemia due to upper GIT bleeding. Esophagogastroduodenoscopy (OGD) documented duodenal growth. Histopathology findings of biopsy taken from the growth revealed, moderately differentiated adenocarcinoma of duodenum. Abdominal computed tomogram (CT) scan showed retroperitoneal mass which could be primary duodenal tumor or para - aortic lymph node. The patient was referred to surgery unit for pancreatico - duodenectomy with the diagnosis of primary duodenal malignancy. In Surgery unit, a left testicular mass was discovered. Ultrasound revealed suspicious mass in left testis. Review of duodenal biopsy (by another pathologist) was asked for. Duodenal metastatic seminoma was the diagnosis which was confirmed by immunohistochemical Stains (that was not done before). Left testicular biopsy showed testicular seminoma .Patient was treated by high inguinal orchiectomy followed by chemotherapy. One year, later the patient had no GIT symptoms, was not anemic and started to put on weight. Follow up endoscopy showed no evidence of tumor in duodenum. There was no evidence of retroperitoneal growth by follow up CT scan.

DISCUSSION

Testis lymphatic drainage is through para aortic lymph nodes .These are in contact with GIT. When testicular malignancy metastasizes to retroperitoneum it may invade GIT causing confusion whether symptoms are primarily from GIT, or they are primarily extra intestinal.

CONCLUSION

High index of suspicion for testicular seminoma must be raised when treating young males with GIT complications like hemorrhage. Testicular seminoma is the most common solid tumor at this age. Sometimes it is the cause behind this complication.

Subfertility increases risk of testicular cancer: evidence from population-based semen samples

OBJECTIVE

To further understand the association between semen quality and cancer risk by means of well defined semen parameters.

DESIGN

Retrospective cohort study.

SETTING

Not applicable.

PATIENT(S)

A total of 20,433 men who underwent semen analysis (SA) and a sample of 20,433 fertile control subjects matched by age and birth year.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Risk of all cancers as well as site-specific results for prostate cancer, testicular cancer, and melanoma.

RESULT(S)

Compared with fertile men, men with SA had an increased risk of testicular cancer (hazard rate [HR] 3.3). When the characterization of infertility was refined using individual semen parameters, we found that oligozoospermic men had an increased risk of cancer compared with fertile control subjects. This association was particularly strong for testicular cancer, with increased risk in men with oligozoospermia based on concentration (HR 11.9) and on sperm count (HR 10.3). Men in the in the lowest quartile of motility (HR 4.1), viability (HR 6.6), morphology (HR 4.2), or total motile count (HR 6.9) had higher risk of testicular cancer compared with fertile men. Men with sperm concentration and count in the 90th percentiles of the distribution (≥178 and ≥579 × 10(6)/mL, respectively), as well as total motile count, had an increased risk of melanoma (HRs 2.1, 2.7, and 2.0, respectively). We found no differences in cancer risk between azoospermic and fertile men.

CONCLUSION(S)

Men with SA had an increased risk of testicular cancer which varied by semen quality. Unlike earlier work, we did not find an association between azoospermia and increased cancer risk.

Advances in the treatment of testicular cancer

Germ cell tumors (GCT) are relatively uncommon, accounting for only 1% of male malignancies in the United States. It has become an important oncological disease for several reasons. It is the most common malignancy in young men 15-35 years old. GCTs are among a unique numbers of neoplasms where biochemical markers play a critical role. Finally, it is a model of curable cancer. In this review we discuss cancer epidemiology, genetics, and therapeutic principles. Recent advances in the management of stage I GCT and controversies in the management of post chemotherapy residual mass are presented.

Testicular germ cell tumours and parental occupational exposure to pesticides: a register-based case-control study in the Nordic countries (NORD-TEST study)

OBJECTIVES

A potential impact of exposure to endocrine disruptors, including pesticides, during intrauterine life, has been hypothesised in testicular germ cell tumour (TGCT) aetiology, but exposure assessment is challenging. This large-scale registry-based case-control study aimed to investigate the association between parental occupational exposure to pesticides and TGCT risk in their sons.

METHODS

Cases born in 1960 or onwards, aged between 14 and 49 years, and diagnosed between 1978 and 2013 in Denmark, Finland, Norway or Sweden, were identified from the respective nationwide cancer registries. Four controls per case were randomly selected from the general national populations, matched on year of birth. Information on parental occupation was collected through censuses or Pension Fund information and converted into a pesticide exposure index based on the Finnish National Job-Exposure Matrix.

RESULTS

A total of 9569 cases and 32,028 controls were included. No overall associations were found for either maternal or paternal exposures and TGCT risk in their sons, with ORs of 0.83 (95% CI 0.56 to 1.23) and of 1.03 (0.92 to 1.14), respectively. Country-specific estimates and stratification by birth cohorts revealed some heterogeneity. Cryptorchidism, hypospadias and family history of testicular cancer were risk factors but adjustment did not change the main results.

CONCLUSIONS

This is the largest study on prenatal exposure to pesticides and TGCT risk, overall providing no evidence of an association. Limitations to assess individual exposure in registry-based studies might have contributed to the null result.

Prospectively Identified Incident Testicular Cancer Risk in a Familial Testicular Cancer Cohort

BACKGROUND

Human testicular germ cell tumors (TGCT) have a strong genetic component and a high familial relative risk. However, linkage analyses have not identified a rare, highly penetrant familial TGCT (FTGCT) susceptibility locus. Currently, multiple low-penetrance genes are hypothesized to underlie the familial multiple-case phenotype. The observation that two is the most common number of affected individuals per family presents an impediment to FTGCT gene discovery. Clinically, the prospective TGCT risk in the multiple-case family context is unknown.

METHODS

We performed a prospective analysis of TGCT incidence in a cohort of multiple-affected-person families and sporadic-bilateral-case families; 1,260 men from 140 families (10,207 person-years of follow-up) met our inclusion criteria. Age-, gender-, and calendar time-specific standardized incidence ratios (SIR) for TGCT relative to the general population were calculated using SEER*Stat.

RESULTS

Eight incident TGCTs occurred during prospective FTGCT cohort follow-up (versus 0.67 expected; SIR = 11.9; 95% CI, 5.1-23.4; excess absolute risk = 7.2/10,000). We demonstrate that the incidence rate of TGCT is greater among bloodline male relatives from multiple-case testicular cancer families than that expected in the general population, a pattern characteristic of adult-onset Mendelian cancer susceptibility disorders. Two of these incident TGCTs occurred in relatives of sporadic-bilateral cases (0.15 expected; SIR = 13.4; 95% CI, 1.6-48.6).

CONCLUSIONS

Our data are the first to indicate that despite relatively low numbers of affected individuals per family, members of both multiple-affected-person FTGCT families and sporadic-bilateral TGCT families comprise high-risk groups for incident testicular cancer.

IMPACT

Men at high TGCT risk might benefit from tailored risk stratification and surveillance strategies.

Concurrent exome-targeted next-generation sequencing and single nucleotide polymorphism array to identify the causative genetic aberrations of isolated Mayer-Rokitansky-Küster-Hauser syndrome

STUDY QUESTION

Can the use of whole-exome sequencing (WES) together with single nucleotide polymorphism (SNP) array help to identify novel causative genes of isolated Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome?

SUMMARY ANSWER

OR4M2 (olfactory receptor, family 4, subfamily M, member 2) and PDE11A (phosphodiesterase 11A) gene loss-of-function variants as well as deletions at 15q11.2, 19q13.31, 1p36.21, and 1q44 were identified as possible commonly altered regions in patients with type 1 MRKH.

WHAT IS KNOWN ALREADY

The isolated form of Müllerian aplasia is the most common subtype of MRKH syndrome, which invariably leads to difficulties producing offspring in affected women. However, there is little information currently available to allow for genetic testing and counseling to be performed for those affected by this syndrome.

STUDY DESIGN, SIZE AND DURATION

This was a case-series genetic study. A total of seven consecutive unrelated women with type 1 MRKH were enrolled. The enrollment and experimental procedures were performed over a 2-year period.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Whole exome-targeted next-generation sequencing and SNP array (Affymetrix Genome-Wide Human SNP Array 6.0) were performed on the first five unrelated women with type 1 MRKH syndrome. The data were combined, and the '3-hit principal' was applied on a genome-wide scale to search for the common causative genes. Quantitative PCR (qPCR) and Sanger sequencing were used to validate the identified genomic copy number losses and variants. Replication tests using direct Sanger sequencing and qPCR were performed on the remaining two women with type 1 MRKH syndrome to support the credibility of the potential candidate genes and deletions.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 3443 damaging variants based on WES were shown to intersect with 1336 copy number variations (deletions) derived from the SNP array. Four highly recurrent deletions at 15q11.2 (80%), 19q13.31 (40%), 1p36.21 (40%) and 1q44 (40%) were identified in the first five women with type 1 MRKH syndrome and were considered to be novel candidate aberrations. A previously reported 1q21.1 deletion was also recurrent in two of the first five women with type 1 MRKH syndrome. The 1q44 and 19q13.31 deletions were present in at least one of the two additional patients. Damaging variants were detected in HNRNPCL1 (heterogeneous nuclear ribonucleoprotein C-like 1), OR2T2 (olfactory receptor, family 2, subfamily T, member 2), OR4M2, ZNF816 (zinc finger protein 816), and PDE11A in several of the initial five patients. Among these, the damaging variants of OR4M2 (located at 15q11.2) and PDE11A were found in at least one of the two additional patients with type 1 MRKH.

LIMITATIONS, REASONS FOR CAUTION

In this study, we only searched for the deletions or damaging variants causing loss-of-function of genes in at least three of the initial five patients (3-hit criteria). Therefore, the study was designed to only detect common causative genes. Genomic duplications and/or rare individual mutations that may have also contributed to MRKH syndrome were not investigated.

WIDER IMPLICATIONS OF THE FINDINGS

This study demonstrated the feasibility of the use of combined data from both WES and SNP arrays for the identification of possible common causative genetic aberrations in patients with type 1 MRKH syndrome on a genome-wide scale. Further validation of our found causative genes is required before applying on genetic testing and counseling.

STUDY FUNDING/COMPETING INTERESTS

The study was supported by grants from the National Science Council of Taiwan (NSC98-2314-B002-105-MY3 and NSC 100-2314-B002-027-MY3). The funding sources had no involvement in the design or analysis of the study. The authors have no competing interests to declare.

TRIAL REGISTRATION NUMBER

Not applicable.

Nontesticular cancers in relatives of testicular germ cell tumor (TGCT) patients from multiple-case TGCT families

Testicular germ cell tumors (TGCT) exhibit striking familial aggregation that remains incompletely explained. To improve the phenotypic definition of familial TGCT (FTGCT), we studied an international cohort of multiple-case TGCT families to determine whether first-degree relatives of FTGCT cases are at increased risk of other types of cancer. We identified 1041 first-degree relatives of TGCT cases in 66 multiple-case TGCT families from Norway and 64 from the United States (combined follow-up of 31,556 person-years). We collected data on all cancers (except nonmelanoma skin cancers) reported by the family informant in these relatives, and we attempted to verify all reported cancer diagnoses through medical or cancer registry records. We calculated observed-to-expected (O/E) standardized incidence ratios, together with 95% confidence intervals (CI), for invasive cancers other than TGCT. We found no increase in risk of cancer overall (Norway O/E = 0.8; 95% CI: 0.6–1.1 and United States O/E = 0.9; 95% CI: 0.7–1.3). Site-specific analyses pooled across the two countries revealed a leukemia excess (O/E = 6.5; 95% CI: 3.0–12.3), deficit of female breast cancer (O/E = 0.0; 95% CI: 0.0–0.6) and increased risk of soft tissue sarcoma (O/E = 7.2; 95% CI: 2.0–18.4); in all instances, these results were based on small case numbers and statistically significant only in Norway. While limited by sample size and potential issues relating to completeness of cancer reporting, this study in multiple-case TGCT families does not support the hypothesis that cancers other than testis cancer contribute to the FTGCT phenotype.

Muscle-building supplement use and increased risk of testicular germ cell cancer in men from Connecticut and Massachusetts

BACKGROUND

No analytic epidemiological study has examined the relationship between use of muscle-building supplements (MBSs) and testicular germ cell cancer (TGCC) risk.

METHODS

We conducted a population-based case-control study including 356 TGCC cases and 513 controls from Connecticut and Massachusetts.

RESULTS

The odds ratio (OR) for ever use of MBSs in relation to risk of TGCC was significantly elevated (OR=1.65, 95% confidence interval (CI): 1.11-2.46). The associations were significantly stronger among early users, men with more types of MBSs used, and longer periods of use.

CONCLUSIONS

MBS use is a potentially modifiable risk factor that may be associated with TGCC.

Genetic and epigenetic analysis of monozygotic twins discordant for testicular cancer

Despite the notion that monozygotic (identical) twins share 100% identical genetic information, genetic differences among monozygotic twin pairs do occur and can be explained by mechanisms occurring during post-zygotic events. Despite such twins being fundamentally "identical", these post-zygotic genetic changes may give rise to phenotypic differences and genetic diseases. Consequently, studies of monozygotic twin pairs discordant for specific genetic diseases represent an important tool for the identification of disease genes. We used array comparative genomic hybridization (aCGH) and methylation arrays to search for genetic and epigenetic differences in blood drawn from four monozygotic twin pairs discordant for testicular germ cell tumors. No consistent differences were identified. A larger twin study would be required to achieve confident discovery of very subtle differences between monozygotic twins discordant for testicular germ cell tumors.

Familial testicular germ cell tumors (FTGCT) - overview of a multidisciplinary etiologic study

This Review summarizes the cumulative results of the National Cancer Institute Clinical Genetics Branch Multidisciplinary Etiologic Study of Familial Testicular Germ Cell Tumors (FTGCT). Initiated 12 years ago, this protocol enrolled 724 subjects from 147 unrelated families with either ≥2 affected men (n = 90) with TGCT or a proband with bilateral TGCT and a negative family history for this cancer (n = 57). Data were collected directly from 162 subjects evaluated at the NIH Clinical Center, and 562 subjects provided information from their home communities (Field Cohort). The primary study aims included (i) ascertaining, enrolling eligible FTGCT kindred, (ii) characterizing the clinical phenotype of multiple-case families, (iii) identifying the underlying genetic mechanism for TGCT susceptibility in families, (iv) evaluating counseling, psychosocial, and behavioral issues resulting from membership in an FTGCT family, and (v) creating an annotated biospecimen repository to permit subsequent translational research studies. Noteworthy findings include (i) documenting the epidemiologic similarities between familial and sporadic TGCT, (ii) demonstrating significantly younger age-at-diagnosis for familial vs. sporadic TGCT, (iii) absence of a dysmorphic phenotype in affected family members, (iv) shifting the focus of gene discovery from a search for rare, highly penetrant susceptibility variants to the hypothesis that multiple, more common, lower penetrance genes underlie TGCT genetic risk, (v) implicating testicular microlithiasis in FTGCT risk, and (vi) observing that aberrant methylation may contribute to FTGCT risk. A clinically based, biospecimen-intensive, multidisciplinary research strategy has provided novel, valuable insights into the etiology of FTGCT, and created a research resource which will support FTGCT clinical and laboratory studies for years to come.

Global incidence and outcome of testicular cancer

Background

Testicular cancer is a rare tumor type accounting for 1% of malignancies in men. It is, however, the most common cancer in young men in Western populations. The incidence of testicular cancer is increasing globally, although a decline in mortality rates has been reported in Western countries. It is important to identify whether the variations in trends observed between populations are linked to genetic or environmental factors.

Methods

Age-standardized incidence rates and age-standardized mortality rates for testicular cancer were obtained for men of all ages in ten countries from the Americas, Asia, Europe, and Oceania using the Cancer Incidence in Five Continents (CI5plus) and World Health Organization (WHO) mortality databases. The annual percent change was calculated using Joinpoint regression to assess temporal changes between geographical regions.

Results

Testicular cancer age-standardized incidence rates are highest in New Zealand (7.8), UK (6.3), Australia (6.1), Sweden (5.6), USA (5.2), Poland (4.9), and Spain (3.8) per 100,000 men. India, China, and Colombia had the lowest incidence (0.5, 1.3, and 2.2, respectively) per 100,000 men. The annual percent changes for overall testicular cancer incidence significantly increased in the European countries Sweden 2.4%, (2.2; 2.6); UK 2.9%, (2.2; 3.6); and Spain 5.0%, (1.7; 8.4), Australia 3.0%, (2.2; 3.7), and China 3.5%, (1.9; 5.1). India had the lowest overall testicular cancer incidence −1.7%, (−2.5; −0.8). Annual percent changes for overall testicular cancer mortality rates were decreasing in all study populations, with the greatest decline observed in Sweden −4.2%, (−4.8; −3.6) and China −4.9%, (−6.5; −3.3).

Conclusion

Testicular cancer is increasing in incidence in many countries; however, mortality rates remain low and most men are cured. An understanding of the risks and long-term side effects of treatment are important in managing men with this disease.

Germinoma in two brothers: case report

We present a third reported case of intracranial germinomas occurring in two brothers. They underwent chemotherapy and radiotherapy after biopsy and are doing well for 10 years and 20 months, respectively. The pertinent literatures are reviewed, and the possible role of heredity in the pathogenesis of familial occurrence of germinomas is discussed.

Cyclic AMP and c-KIT signaling in familial testicular germ cell tumor predisposition

BACKGROUND

Familial testicular germ cell tumors (FTGCTs) are hypothesized to result from the combined interaction of multiple low-penetrance genes. We reported inactivating germline mutations of the cAMP-binding phosphodiesterase 11A (PDE11A) as modifiers of FTGCT risk. Recent genome-wide association studies have identified single-nucleotide polymorphisms in the KITLG gene, the ligand for the cKIT tyrosine kinase receptor, as strong modifiers of susceptibility to both familial and sporadic testicular germ cell tumors.

DESIGN

We studied 94 patients with FTGCTs and 50 at-risk male relatives from 63 unrelated kindreds, in whom the PDE11A gene had been sequenced by investigating the association between KITLG genome-wide association study single-nucleotide polymorphisms rs3782179 and rs4474514 and FTGCT risk in these patients and in 692 controls. We also examined cAMP and c-KIT signaling in testicular tissues and cell lines and extended the studies to 2 sporadic cases, one with a PDE11A defect and one without, as a comparison.

RESULTS

We found a higher frequency of the KITLG risk alleles in FTGCT patients who also had a PDE11A sequence variant, compared with those with a wild-type PDE11A sequence. In NTERA-2 and Tcam-2 cells transfected with the mutated forms of PDE11A (R52T, F258Y, Y727C, R804H, V820M, R867G, and M878V), cAMP levels were significantly higher, and the relative phosphodiesterase activity was lower than in the wild-type cells. KITLG expression was consistently increased in the presence of PDE11A-inactivating defects, both at the RNA and protein levels, in familial testicular germ cell tumors. The 2 sporadic cases that were studied, one with a PDE11A defect and another without, agreed with the data in FTGTCT and in the cell lines.

CONCLUSIONS

Patients with FTGCT and PDE11A defects also carry KITLG risk alleles more frequently. There may be an interaction between cAMP and c-KIT signaling in predisposition to testicular germ cell tumors.