Testicular microlithiasis in paediatric patients with Klinefelter syndrome from infancy till adolescence: early start of degenerative process in the testes-preliminary results

To present the results of testicular ultrasonography supported by clinical and hormonal aspects in paediatric patients with Klinefelter syndrome (KS). Prospective analysis of medical files of 20 patients diagnosed with KS between 2016 and 2022. Assessed data included analysis of causes of referral, ultrasound, and clinical characterisation with hormonal evaluation of serum FSH, LH, testosterone, inhibin B, and anti-Müllerian hormone. Non-mosaic Klinefelter syndrome (47, XXY) was diagnosed in 65% of cases (13/20) by the geneticist (including 7 cases prenatally), in 25% (5/20) by the endocrinologist and in 10% (2/20) by the hematologist. Ultrasound assessment revealed bilateral testicular microlithiasis (TM) in all patients. The youngest KS patient with TM was 3 months old. TM patterns have not changed during follow-ups of up to 6 years in any of the patients. In all KS patients markedly reduced echogenicity and in pubertal KS patients, also irregular echostructure of the testes was observed. The hormonal patterns observed in the study group were typical for those already described in KS. Sertoli and Leydig cell function was intact in prepubertal patients and deteriorated after the start of puberty.

CONCLUSION

Although the degenerative process in the testicular tissue starts very early in the testes in KS and is reflected in morphological changes seen in ultrasonography, Sertoli and Leydig cell hormonal function is normal in prepubertal KS patients.

WHAT IS KNOWN

• So far, normal Leydig and Sertoli cell function was observed in infants and prepubertal KS patients.

WHAT IS NEW

• The morphological changes in the testes in KS may already be seen in early infancy.

Is testicular microlithiasis associated with testicular pathologies in children?

PURPOSE

To analyze the association of testicular pathologies with TM.

METHOD

The retrospective study included pediatric patients who underwent scrotal ultrasonography (US) due to complaints, including testicular pain, discomfort, swelling, scrotal redness in our clinic between June 2020 and January 2022. The patients were divided into two groups. Group 1; patients were diagnosed with testicular pathology or presented with testicular pain. Group 2; patients without testicular pathology or complaints. Patients were also classified as having undescended testis, epididymo-orchitis, varicocele and testicular pain without testicular pathology in group 1. Group 1 and subgroups of group 1 were compared with group 2 for the presence of TM.

RESULTS

A total of 516 patients were included in the study. Median age at the time of US examination was 24 months (range 1 month-17 years). There was no significant difference between groups 1 and 2, and boys with undescended testis and group 2 with regard to the presence of TM (p = 0.85, p = 0.55, respectively). TM was significantly higher in patients who had undergone orchiopexy and presented with testicular pain compared to group 2 (p = 0. 013, p = 0.03, respectively). TM was not detected in patients with epididymo-orchitis, varicocele.

CONCLUSION

We found no association between TM and testicular pathologies. Testicular pain may be a symptom of microlithiasis.

Incidence of testicular microlithiasis after orchidopexy for cryptorchidism and its risk factors: A retrospective cohort study

INTRODUCTION

Testicular microlithiasis (TML) is detected using scrotal ultrasound (US) and is characterized by hyperechoic non-shadowing foci 1-3 mm in diameter within the testicular parenchyma. Although a history of orchidopexy is a known risk factor for TML, and TML is a relatively common condition in postoperative cryptorchidism patients, no previous report has focused on risk factors for TML after orchidopexy.

OBJECTIVE

The aims of this study were to evaluate the time-dependent incidence of TML after orchidopexy for cryptorchidism and to identify risk factors for TML.

STUDY DESIGN

This study included patients who underwent primary orchidopexy for cryptorchidism between 2004 and 2018 and could be evaluated using scrotal US before and after the procedure. Patients with chromosomal abnormalities and those with preoperative TML were excluded. The Kaplan-Meier method was used to assess postoperative TML appearance. The Cox proportional hazard model was used to evaluate three potential risk factors for postoperative TML: higher testicular position (proximal to the external inguinal ring), delayed orchidopexy (after 18 months of corrected age), and bilateral cryptorchidism.

RESULTS

A total of 214 testes from 163 patients were eligible for inclusion (operative age and follow-up time: 2.2 years ± 18 months and 6.3 years ± 46 months, respectively). TML was found in 14/163 patients (8.6%) and 17/214 testes (8.1%). No testicular tumors were discovered during follow-up. The time-dependent TML incidence was 6.0% at 5 years and 11.2% at 10 years after surgery (Summary figure). A higher testicular location proximal to the external inguinal ring was found to be an independent risk factor in the Cox proportional hazard model (hazard ratio 6.18, 95% confidence interval 1.37-27.9, Summary figure).

DISCUSSION

Our findings show that the incidence of postoperative TML increases for approximately 10 years following orchidopexy and is associated with a higher testicular location proximal to the external inguinal ring at surgery. In the adult population, TML with a history of cryptorchidism is a known risk factor of testicular malignancy. Given that more than 20% of boys with a higher testicular position developed TML, US evaluation to detect TML during pubety is feasible for the patients with a history of orchidopexy.

CONCLUSION

The incidence of postoperative TML in boys with cryptorchidism rises until puberty and is strongly associated with a higher testicular position at orchidopexy.

On behalf of the EAU pediatric urology guidelines panel

INTRODUCTION

The exact correlation of testicular microlithiasis (TM) with benign and malignant conditions remains unknown, especially in the paediatric population. The potential association of TM with testicular malignancy in adulthood has led to controversy regarding management and follow-up.

OBJECTIVE

To determine the prognostic importance of TM in children in correlation to the risk of testicular malignancy or infertility and compare the differences between the paediatric and adult population.

STUDY DESIGN

We performed a literature review of the Medline, Embase and Cochrane controlled trials databases until November 2020 according to the Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) Statement. Twenty-six publications were included in the analysis.

RESULTS

During the follow-up of 595 children with TM only one patient with TM developed a testicular malignancy during puberty. In the other 594 no testicular malignancy was found, even in the presence of risk factors. In the adult population, an increased risk for testicular malignancy in the presence of TM was found in patients with history of cryptorchidism (6% vs 0%), testicular malignancy (22% vs 2%) or sub/infertility (11-23% vs 1.7%) compared to TM-free. The difference between paediatric and adult population might be explained by the short duration of follow-up, varying between six months and three years. With an average age at inclusion of 10 years and testicular malignancies are expected to develop from puberty on, testicular malignancies might not yet have developed.

CONCLUSION

TM is a common incidental finding that does not seem to be associated with testicular malignancy during childhood, but in the presence of risk factors is associated with testicular malignancy in the adult population. Routine monthly self-examination of the testes is recommended in children with contributing risk factors from puberty onwards. When TM is still present during transition to adulthood a more intensive follow-up could be considered.

Shorter anogenital distance is observed in patients with testicular microlithiasis using magnetic resonance imaging

OBJECTIVE

To investigate the anogenital distance in patients with and without testicular microlithiasis (TML).

METHODS

A total of 101 patients underwent a conventional standard clinical B-mode scrotal ultrasonography and scrotal MRI. The patients were divided into two groups: patients with TML and non-TML. The latter served as control group. The anogenital distance was measured by a straight line from center of the anus to the posterior base of scrotum using MRI.

RESULTS

In the TML group, mean AGD was 5.4 (± 1.07) cm (range 29-79 mm), and in non-TML 5.9 (± 1.03) cm (range 35-85 mm) (p = 0.04).

CONCLUSION

MRI is a useful tool to measure the AGD. It is easy to perform without any discomfort to patients. We found AGD to be lower in patients with TML.

Incidence characteristics of testicular microlithiasis and its association with risk of primary testicular tumors in children: a systematic review and meta-analysis

BACKGROUND

To systematically evaluate the incidence characteristics of testicular microlithiasis (TM) in children and its association with primary testicular tumors (PTT).

METHODS

A systematic review and meta-analysis were conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement. A priori protocol was registered in the PROSPERO database (CRD42018111119), and a literature search of all relevant studies published until February 2019 was performed. Prospective, retrospective cohort, or cross-sectional studies containing ultrasonography (US) data on the incidence of TM or the association between TM and PTT were eligible for inclusion.

RESULTS

Of the 102 identified articles, 18 studies involving 58,195 children were included in the final analysis. The overall incidence of TM in children with additional risk factors for PTT was 2.7%. In children, the proportion of left TM in unilateral cases was 55.7%, the frequency of bilateral TM was 69.0%, and proportion of classic TM was 71.8% [95% confidence interval (CI) 62.4-81.1%, P = 0.0, I² = 0.0%]. About 93.5% of TM remained unchanged, and newly detected PTT rate was very low (4/296) during follow-up. The overall risk ratio of TM in children with a concurrent diagnosis of PTT was 15.46 (95% CI 6.93-34.47, P < 0.00001).

CONCLUSIONS

The incidence of TM in children is highly variable. Nonetheless, TM is usually bilateral, of the classic type, and remains stable or unchanged at follow-up. Pediatric patients with TM and contributing factors for PTT have an increased risk for PTT; however, there is no evidence to support mandatory US surveillance of children with TM.

Is testicular microlithiasis a really innocent condition? Its effects on oncological outcomes of germ cell testicular cancer: An observational study

OBJECTIVES

Although it is a well known condition that presence of testicular microlithiasis (TM) with the co-occurrence of specific risk factors such as historyof previous germ cell testicular cancer (GCTC), infertility, undescended testes or atrophic testes have high risks for GCTC development, TM is still a controversial topic. Its effects on oncological outcomes have still not been investigated in detail. In this study, we aimed to evaluate whether the presence of TM has an effect on GCTC prognosis and oncological outcomes.

METHODS

Seventy five patients among 93 patients who underwent radical orchidectomy between January 2010 and February 2016 were selected and divided into two groups. Group I consisted of 51 patients without TM. Group II consisted of 24 patients with TM. Each groups were compared in terms of demographic datas, prognostic risk factors, complete blood count parameters and oncological outcomes.

RESULTS

During the median follow-up of 58 (1-106) months, a significantly higher local recurrence rate (54.2% vs. 3.9%, p<0.001) distant metastasis rate (58.3% vs. 5.9%, p<0.001) and lower cancer-specific survival rate (45.8% vs. 94.1%, p<0.001) were observed in patients with TM. In this group, the duration of recurrence-free survival (47.65±9.45 vs.101.96±2.80 months, p<0.001), metstais-free survival (49.50±8.88 vs. 100.00±3.36 months, p<0.001) and cancer-specific survival (54.37±8.76  vs. 100.19±3.25 months, p<0.001) were also statisticaly lower. In multivariate analysis, β-hCG, LDH, neutrophil/lymphocyte ratio, monocyte/lymphocyte ratio and the presence of undescended testis were found as independent predictive factors for local recurrence, distant metastasis and cancer-specific survival. Red blood cell distribution width and the presence of testicular microlithiasis were found to be independent predictive factors for local recurrence.

CONCLUSION

According to our results, bilateral TM was associated with higher rates of local recurrence, distant metastasis and cancer spesific mortality in presenceof risk factors, regardless of classic or limited microlithiasis.

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.

[Relationship between testicular microcalcifications and clinical characteristics in patients with testicular cancer]

INTRODUCTION

Testicular microlithiasis (TM) is an uncommon finding in general male population. These calcifications are reported by testicular ultrasound performed by some testicular pathology and constitute an incidental finding. The presence of TM is regularly associated to testicular neoplasms.

OBJECTIVES

To investigate the relationship between clinical and demographic factors, comorbidities and tumor biomarkers, and the presence or absence of microlithiasis in patients with testicular cancer.

MATERIAL AND METHODS

A retrospective study including a total of 66 patients diagnosed with testicular carcinoma from 2012 to 2017 in a hospital in Northeastern Mexico. The total of patients was divided into 2 groups according to the presence or absence of MT and the clinical features of these were analyzed.

RESULTS

There was a general prevalence of TM of 31.8%. The main tumor found in the pathology reports corresponded to the non seminomatous germ cells tumor (54.4%). The incidence of metastasis to organs was of 27.3%. No statistically significant differences were found when comparing the variables of interest in the group with and without MT. A relationship was found between the elevation of alpha-fetoprotein and non-seminomatous tumors compared to seminomatous tumors (PY=Y.003).

CONCLUSIONS

According to the results obtained, it can be suggested that TM is a clinical finding that is not related to the prognosis of the disease or any of the comorbidities and clinical data analyzed in our study.

Phenotypic testicular abnormalities and pubertal development in boys with McCune-Albright syndrome

Aim of this survey is to review the few available literature data on pathophysiologic and clinical aspects of pubertal development in boys with McCune-Albright syndrome (MAS). On the basis of such analysis, we concluded that:

1) peripheral precocious puberty (PPP) is significantly more infrequent in boys than in girls; 2) the most common testicular abnormality at MAS presentation is macroorchidism, that may be either monolateral or bilateral; 3) macroorchidism is not always associated with clinical and biochemical evidence of PPP; 4) testicular microlothiasis is distinctly more frequent in boys with MAS than in those without MAS; 5) the available therapeutic schedules have to be adopted already at MAS presentation only in the cases with PPP.

European Society of Paediatric Radiology Abdominal Imaging Task Force recommendations in paediatric uroradiology, part X: how to perform paediatric gastrointestinal ultrasonography, use gadolinium as a contrast agent in children, follow up paediatric testicular microlithiasis, and an update on paediatric contrast-enhanced ultrasound

At the European Society of Paediatric Radiology (ESPR) annual meeting 2017 in Davos, Switzerland, the ESPR Abdominal (gastrointestinal and genitourinary) Imaging Task Force set out to complete the suggestions for paediatric abdominal imaging and its procedural recommendations. Some final topics were addressed including how to perform paediatric gastrointestinal ultrasonography. Based on the recent approval of ultrasound (US) contrast agents for paediatric use, important aspects of paediatric contrast-enhanced US were revisited. Additionally, the recent developments concerning the use and possible brain deposition of gadolinium as a magnetic resonance imaging contrast agent were presented. The recommendations for paediatric use were reissued after considering all available evidence. Recent insights on the incidence of neoplastic lesions in children with testicular microlithiasis were discussed and led to a slightly altered recommendation.

Testicular microlithiasis and testicular tumor: a review of the literature

Introduction

There are numerous scientific publications on testicular microlithiasis (TML) detected during ultrasound (US) examination. We wished to update the data.

Methods

PubMed was used to identify original articles published between 1998 and May 2017 describing the association between TML and testicular tumor. Studies were only included if TML was diagnosed by US. Studies were then classified into subgroups according to the following criteria: asymptomatic, symptomatic, infertility, cryptorchidism, family or personal history of testicular cancer, and “no given reason for US”. A Z-Test was used to identify differences within these subgroups. In addition, we identified prospective cohorts of TML patients. Numbers, duration of follow-up, and occurrence of the “testicular tumor” event were recorded for each of them.

Results

One hundred and seventy-five articles were identified, 40 of which were included. Our review has not showed a clear evidence that cryptorchidism associated with TML is a risk factor for testicular tumor. However, there seems to be a correlation between infertility associated with TML and a higher tumor risk. There were not enough studies to confirm a relationship between family or personal history associated with TML and the tumor risk. There was also a correlation with a higher tumor risk for symptomatic associated with TML and “no given reason for US” plus TML groups. However, these groups are assumed to contain bias and caution must be taken regarding conclusions. Regarding the prospective cohort studies, 16 testicular tumors appeared in the follow-up of patients with TML, 13 patients had risk factors.

Conclusion

In cases of TML incidental finding by US with the presence of risk factors (personal history of testicular cancer, testicular atrophy, infertility, cryptorchidism) a consultation with a specialist should be considered. In the absence of risk factors, the occurrence of testicular cancer in patients with TML is similar to the risk of the general population.

Prevalence and risk factors of testicular microlithiasis in patients with hypospadias: a retrospective study

BACKGROUND

It has been described that the incidence of testicular microlithiasis is high in several congenital disorders which may be associated with testicular impairment and infertility. Several reports have shown that a prepubertal or pubertal hormonal abnormality in the pituitary-gonadal axis was identified in some patients with hypospadias that is one of the most common disorders of sex development. However, exact prevalence or risk factors of testicular microlithiasis in patients with hypospadias have not reported so far. In the present study, to clarify the prevalence and risk factors of testicular microlithiasis in patients with hypospadias, a retrospective chart review was performed.

METHODS

Children with hypospadias who underwent testicular ultrasonography between January 2010 and April 2016 were enrolled in the present study. Severity of hypospadias was divided into mild and severe. The prevalence and risk factors of testicular microlithiasis or classic testicular microlithiasis were examined.

RESULTS

Of 121 children, mild and severe hypospadias were identified in 66 and 55, respectively. Sixteen children had undescended testis. Median age at ultrasonography evaluation was 1.7 years old. Testicular microlithiasis and classic testicular microlithiasis were documented in 17 children (14.0%) and 8 (6.6%), respectively. Logistic regression analysis revealed that presence of undescended testis was only a significant factor for testicular microlithiasis and classic testicular microlithiasis. The prevalence of testicular microlithiasis or classic testicular microlithiasis was significantly higher in children with undescended testis compared to those without undescended testis (testicular microlithiasis; 43.8% versus 9.5% (p = 0.002), classic testicular microlithiasis; 37.5% versus 1.9% (p < 0.001).

CONCLUSIONS

The current study demonstrated that the presence of undescended testis was only a significant risk factor for testicular microlithiasis or classic testicular microlithiasis in patients with hypospadias. As co-existing undescended testis has been reported as a risk factor for testicular dysfunction among patients with hypospadias, the current findings suggest that testicular microlithiasis in children with hypospadias may be associated with impaired testicular function. Conversely, patients with isolated HS seem to have lower risks for testicular impairment. Further investigation with longer follow-up will be needed to clarify these findings.

Role of calcifying nanoparticles in the development of testicular microlithiasis in vivo

BACKGROUND

Calcifying nanoparticles (NPs) have been proven to be associated with a variety of pathological calcification and previously detected in semen samples from patients with testicular microlithiasis (TM). The present study was designed to test the hypothesis if human-derived NPs could invade the seminiferous tubules and induce TM phenotype.

METHODS

The animals were divided into three groups. Normal saline (0.2 mL) was injected into the proximal right ductus deferens in group A as a control group. The experimental groups, B and C received Escherichia coli (10⁶ cfu/mL, 0.2 mL) and human-derived NPs suspension (0.2 mL), respectively. Rats were euthanized in 2 batches at 2 and 4 weeks. Testicular pathology, ultrastructure and inflammatory mediators were assessed.

RESULTS

Chronic inflammatory changes were observed at 2 weeks in both groups B and C. Moreover, the innermost layer of sperm cells were structurally impaired and a zone of concentrically layered collagen fibers around the human NPs body was formed in the lumen of the seminiferous tubule in group C only, in which TM phenotype of remarkable calcification surrounded by cellular debris within the seminiferous tubules was built at 4 weeks.

CONCLUSIONS

The results obtained from our study suggested a potential pathogenic effect of NPs in the development of calcification within the seminiferous tubules, which should be addressed in the future studies.

A case report

OBJECTIVES

To report our experience with a case of a child with bilateral testicular micro-lithiasis (TML) who developed bilateral metachronous testicular germ cell tumor (TGCT) and determine the most appropriate follow-up and care management in children with testicular micro calcifications in regards to the theoretical risk of testicular cancer.

CASE REPORT

A 12 year-old boy was diagnosed with TGCT and TML. Ten years after complete remission, he presented with a recurrence on the contralateral testis. Genetic screening was performed on both resected and the patient's karyotype was analyzed.

RESULTS

Blood karyotype was normal. Aberrations were found in the tumor karyotype. CGH array showed alterations in chromosome arm 12p.

DISCUSSION

TML is frequently associated with testicular malignancy in adults: in 16.9% of cases the normal contralateral testicle develops TML in TGCT. Recent works of literature find no relationship between TML and cancer in general, but in patients with additional risks, the relationship becomes stronger. Some authors suggest that environmental components and genetics are determinant factors. This is highly suspected in our reported case. It would seem that TML is not a precancerous lesion per se, but rather a marker of an at-risk situation. Long term evolution is uncertain and regular self-palpation that starts before puberty is the only way to ensure proper screening and monitoring.

CONCLUSION

TML have been suspected to be a sign of testicular dysgenesis syndrome, which yields a risk of developing TGCT in case of noxious associations. In patients with a history of TGCT contralateral TML is alarming and aggressive surgical management should be discussed. Therapeutic education of these patients on self-palpation is the best way to ensure proper follow-up.

Intratubular large cell hyalinizing Sertoli cell tumor of the testis presenting with prepubertal gynecomastia: a case report

Intratubular large cell hyalinizing Sertoli cell neoplasia (ITLCHSCN) resulting from Sertoli cells of the testis are mainly reported in young adults and these are rarely seen in childhood. The most common presenting symptoms of the patients diagnosed with ITLCHSCN are gynecomastia, enlargement in the testicles, increase in growth velocity, and advanced bone age. Symptoms are basically resulting from increased aromatase enzyme activity in Sertoli cells. In this case report, an eight-and-a-half-year-old case presenting with complaint of bilateral gynecomastia since two years, showing no endocrine abnormality in laboratory during two years of follow-up, determined to have progression in bilateral gynecomastia, increase in testicular volumes, advanced bone age, increase in growth velocity in the clinical follow-up, and diagnosed with ITLCHSCN after testis biopsy was presented.

Pediatric scrotal ultrasound: review and update

In this pictorial essay the authors review the normal sonographic gray-scale and Doppler appearance of the pediatric scrotum with an emphasis on technique. The authors present an update on ultrasound diagnosis and outcomes in testicular torsion and differentiation from other acute scrotal processes, as well as sonographic imaging of testicular microlithiasis and uncommon or atypical scrotal masses including splenogonadal fusion, polyorchidism, meconium peritonitis and epidermoid cyst. Further, the authors discuss testicular neoplasms in the context of testicular microlithiasis.

Evidence-based paediatric surgical oncology

Surgeons play a pivotal role in the decision-making and multidisciplinary management of childhood solid tumours.¹ Evidence-based medicine-"aims to optimise decision making by emphasising on the use of best evidence from well-designed conducted research." This article offers a brief overview in an effort to demonstrate how a selection of well-conducted, recently published studies can help address some topical and controversial themes in paediatric surgical oncology practice.

Changes of calcific density in pediatric patients with testicular microlithiasis

Purpose

Testicular microlithiasis (TM) is a relatively rare clinical entity of controversial significance characterized by the existence of hydroxyapatite microliths located in the seminiferous tubules. The aim of this study was to observe the natural course of changes in the calcific density of pediatric TM.

Materials and Methods

We included a total of 23 TM patients undergoing scrotal ultrasound (US) on at least two occasions from July 1997 to August 2014. We retrospectively analyzed the patient characteristics, clinical manifestations, specific pathological features, and clinical outcomes. We measured the calcified area and compared the calcific density between the initial and final USs.

Results

The mean age at diagnosis was 11.3±4.6 years, and the follow-up period was 79.1±38.8 months (range, 25.4-152.9 months). During the follow-up period, no patients developed testicular cancer. Calcific density on US was increased in the last versus the initial US, but not to a statistically significant degree (3.74%±6.0% vs. 3.06%±4.38%, respectively, p=0.147). When we defined groups with increased and decreased calcification, we found that diffuse TM was categorized into the increased group to a greater degree than focal TM (10/20 vs. 4/23, respectively, p=0.049). In addition, five of eight cases of cryptorchidism (including two cases of bilateral cryptorchidism) were categorized in the increased calcification group.

Conclusions

Diffuse TM and cryptorchidism tend to increase calcific density. Close observation is therefore recommended for cases of TM combined with cryptorchidism and cases of diffuse TM.

RBPJ in mouse Sertoli cells is required for proper regulation of the testis stem cell niche

Stem cells are influenced by their surrounding microenvironment, or niche. In the testis, Sertoli cells are the key niche cells directing the population size and differentiation fate of spermatogonial stem cells (SSCs). Failure to properly regulate SSCs leads to infertility or germ cell hyperplasia. Several Sertoli cell-expressed genes, such as Gdnf and Cyp26b1, have been identified as being indispensable for the proper maintenance of SSCs in their niche, but the pathways that modulate their expression have not been identified. Although we have recently found that constitutively activating NOTCH signaling in Sertoli cells leads to premature differentiation of all prospermatogonia and sterility, suggesting that there is a crucial role for this pathway in the testis stem cell niche, a true physiological function of NOTCH signaling in Sertoli cells has not been demonstrated. To this end, we conditionally ablated recombination signal binding protein for immunoglobulin kappa J region (Rbpj), a crucial mediator of NOTCH signaling, in Sertoli cells using Amh-cre. Rbpj knockout mice had: significantly increased testis sizes; increased expression of niche factors, such as Gdnf and Cyp26b1; significant increases in the number of pre- and post-meiotic germ cells, including SSCs; and, in a significant proportion of mice, testicular failure and atrophy with tubule lithiasis, possibly due to these unsustainable increases in the number of germ cells. We also identified germ cells as the NOTCH ligand-expressing cells. We conclude that NOTCH signaling in Sertoli cells is required for proper regulation of the testis stem cell niche and is a potential feedback mechanism, based on germ cell input, that governs the expression of factors that control SSC proliferation and differentiation.

Incidental discovery of testicular microlithiasis: what is the importance of ultrasound surveillance? Two case reports

Many studies have demonstrated an association between diffuse bilateral testicular microlithiasis (TM) and gonadal and extragonadal germ cell tumors. Nevertheless, it is still uncertain whether ultrasound surveillance is really necessary in patients with TM in the absence of other risk factors such as previous testicular cancer, a history of cryptorchidism or testicular atrophy. We report the cases of a 33- and a 39-year-old man presenting with a retroperitoneal extragonadal tumor. The first patient underwent an MRI examination in order to rule out a lumbosacral hernia: MRI images showed no slipped disks but a voluminous retroperitoneal solid mass. The histological analysis revealed an immature teratoma. The second patient came to the emergency department complaining of abdominal pain, vomiting, weight loss and mild jaundice: ultrasound examination showed a large, ill-defined heterogeneous abdominal mass, confirmed by CT and MRI examination. The histology diagnosed a yolk sac tumor. In both patients, the testicular sonography was performed to rule out a focal lesion, but it displayed bilateral TM without a focal testicular mass. Based on our direct experience, we highlight the importance of annual ultrasonographic surveillance of the testis and the retroperitoneal space in patients with occasionally detected TM.