Raman Spectroscopic Analysis Identifies Testicular Microlithiasis as Intratubular Hydroxyapatite

Testicular biopsies in men with testicular microlithiasis and additional risk factors for cancer: A case series

BACKGROUND

Testicular microlithiasis is the presence of small calcifications in the testicular parenchyma. The association between testicular microlithiasis and germ cell neoplasia in situ, a precursor to testicular cancer, is still unclear.

OBJECTIVES

To determine the incidence of germ cell neoplasia in situ in men with testicular microlithiasis and evaluate the indication for testicular biopsy according to risk factors in the form of male infertility/reduced semen quality, testicular atrophy, and history of cryptorchidism.

MATERIALS AND METHODS

This retrospective case series included all patients diagnosed with testicular microlithiasis who underwent testicular biopsies at three hospitals in Denmark between 2007 and 2021. The medical records of 167 patients were reviewed, and data on patient demographics, testicular microlithiasis characteristics, risk factors, histological findings, and treatments were collected. The main outcome measure was the incidence of germ cell neoplasia in situ in relation to each risk factor. The data were analyzed using descriptive statistics. Logistic regression was used to examine the odds ratio of germ cell neoplasia in situ in patients with testicular microlithiasis and testicular atrophy.

RESULTS

Germ cell neoplasia in situ was found in 13 out of 167 patients (7.8% [95% confidence interval: 4.3, 13.2]). Eleven of these had testicular atrophy resulting in a significantly higher incidence in this group than other risk factors (odds ratio 9.36 [95% confidence interval: 2.41, 61.88]; p = 0.004).

DISCUSSION

The study comprises the largest cohort to date of men who have undergone testicular biopsies because of testicular microlithiasis and additional risk factors. Limitations include its retrospective design, and relatively low absolute numbers of patients with germ cell neoplasia in situ on biopsies.

CONCLUSION

This study found that men with testicular microlithiasis and testicular atrophy are at an increased risk of germ cell neoplasia in situ. Additionally, our results indicate that biopsies should be considered in men with a combination of subfertility and bilateral testicular microlithiasis. Our findings do not support testicular biopsies for men with testicular microlithiasis and other risk factors.

Increased serum creatinine associated with testicular microlithiasis in adult Japanese men: A retrospective cohort study

BACKGROUND

Testicular microlithiasis (TM) is thought to be associated with testicular tumors and impaired spermatogenesis; however, its etiology remains unclear.

OBJECTIVES

To identify factors, other than testicular function, that are associated with testicular microlithiasis.

MATERIALS AND METHODS

We enrolled males who underwent ultrasound examination of the scrotum at Tokyo Dental College Ichikawa General Hospital. The patients were categorized into two groups: those with or those without testicular microlithiasis. Background and blood test data were compared between the groups.

RESULTS

Testicular microlithiasis was observed in 72 of the 828 (8.7%) patients enrolled. Ages ranged from 15 to 87 years (mean age, 40.0 years). A history of germ cell tumor was significantly more prevalent in patients with testicular microlithiasis than in those without (1.3 vs. 16.7%; p < 0.001). Blood test data showed that, patients with testicular microlithiasis had significantly higher serum creatinine levels (0.91 vs. 1.04 mg/dL; p = 0.046) and lower calcium levels (9.4 vs. 9.3 mg/dL; p = 0.031) than those without. Serum creatinine levels (> 1.00 mg/dL) and germ cell tumors were significantly associated with testicular microlithiasis in both univariate and multivariate analyses. The prevalence of testicular microlithiasis increased in patients older than 50 years. Age (> 50 years) was associated with testicular microlithiasis in univariate analysis. The mean body weight tended to be heavier (70.7 vs. 72.2 kg; p = 0.051) and epididymitis was observed more frequently (3.2 vs. 8.3%; p = 0.056) in patients with testicular microlithiasis than in those without.

DISCUSSION AND CONCLUSION

A history of testicular tumors and elevated serum creatinine levels were associated with testicular microlithiasis. Testicular microlithiasis was observed across all age groups, with a tendency to increase in patients older than 50 years. Patients with testicular microlithiasis were slightly heavier and had a higher prevalence of epididymitis than those without. Our findings suggest that, in addition to testicular dysgenesis, other factors are involved in the development of testicular microlithiasis.

A dual-center study of predictive factors for sperm retrieval through microdissection testicular sperm extraction and intracytoplasmic sperm injection outcomes in men with non-mosaic Klinefelter syndrome

PURPOSE

This study evaluated the predictors of sperm retrieval (SR) in non-mosaic Klinefelter syndrome (KS) patients undergoing microsurgical testicular sperm extraction (mTESE). The cutoff values of the predictors of SR and overall pregnancy rates after intracytoplasmic sperm injection (ICSI) were analyzed for the positive SR (PSR) cases.

MATERIALS AND METHODS

The study was a dual-center retrospective study. Overall 118 patients with KS underwent mTESE between January 2011 and July 2021. Clinicopathological factors including comorbidities, endocrine profiles, and testicular volumes were analyzed.

RESULTS

A total of 58 patients showed PSR (49.2%) and 60 patients (50.8%) had negative SR (NSR). The mean overall age of the patients was 32.5 years. The NSR patients had a significantly greater prevalence of obesity, diabetes mellitus, and cerebrovascular disease. The PSR group had a significantly higher left testis mean volume (p=0.039). The differences between the two study groups regarding follicular-stimulating hormone, luteinizing hormone, and testosterone variations at 1 and 3 months after mTESE were insignificant. Preoperative mean neutrophil-to-lymphocyte ratio was significantly greater in the NSR group (p=0.011), but the platelet-to-lymphocyte ratio showed no significant difference between the two study groups. A live child birth was achieved in 53.4% of the PSR patients. Multivariate logistic analysis showed that total testicular volume >3.93 mL, left testis volume >1.79 mL, and neutrophil-to-lymphocyte ratio ≤1.82 were significantly associated with PSR.

CONCLUSIONS

mTESE-ICSI is a feasible method for KS patients to have a child, and total testicular volume, left testis volume, and neutrophil-to-lymphocyte ratio might be predictors of successful SR.

Application and Progress of Raman Spectroscopy in Male Reproductive System

Raman spectroscopy is a fast-developing, unmarked, non-invasive, non-destructive technique which allows for real-time scanning and sampling of biological samples in situ, reflecting the subtle biochemical composition alterations of tissues and cells through the variations of spectra. It has great potential to identify pathological tissue and provide intraoperative assistance in clinic. Raman spectroscopy has made many exciting achievements in the study of male reproductive system. In this review, we summarized literatures about the application and progress of Raman spectroscopy in male reproductive system from PubMed and Ovid databases, using MeSH terms associated to Raman spectroscopy, prostate, testis, seminal plasma and sperm. The existing challenges and development opportunities were also discussed and prospected.

Testicular microlithiasis defines a subgroup of azoospermic men with low rates of sperm retrieval

OBJECTIVE

To investigate the prevalence of testicular microlithiasis and its association with sperm retrieval rates and histopathology in men with non-obstructive azoospermia.

METHODS

A total of 120 men underwent scrotal ultrasonography prior to microsurgical testicular sperm extraction. Sperm retrieval rate, testicular histopathology, testicular size, reproductive hormones, karyotyping, Y chromosome microdeletion analyses, and presence of varicoceles and hydroceles were compared between men with and without testicular microlithiasis.

RESULTS

The total sperm retrieval rate was 40%. Ten men with normal spermatogenesis were excluded. The remaining 110 men with non-obstructive azoospermia were analyzed and testicular microlithiasis was detected in 16 of them (14.5%). The sperm retrieval rate in that subgroup was only 6.2% (1/16) as opposed to 39.4% (37/94) in men with non-obstructive azoospermia and no evidence of microlithiasis (P = 0.009). The mean right and left testicular diameters were significantly lower in the microlithiasis group (P = 0.04). On multivariate logistic regression analysis, the presence of mictolithiasis (odds ratio 7.4, 95% confidence interval 2.3, 12.2; P = 0.01) was the only independent predictor of unsuccessful sperm retrieval. The 15 patients with microlithiasis and without successful sperm extraction were diagnosed by histopathology as having Sertoli cells only. The 16th patient with successful sperm retrieval had a histopathology of mixed atrophy and was diagnosed with Klinefelter syndrome.

CONCLUSION

The presence of testicular microlithiasis is associated with low sperm retrieval rates among our cohort of men with non-obstructive azoospermia undergoing scrotal ultrasonography prior to microsurgical testicular sperm extraction. Larger, prospective studies should be conducted to confirm these findings.

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.

Multiple Pathways for Pathological Calcification in the Human Body

Biomineralization of skeletal components (e.g., bone and teeth) is generally accepted to occur under strict cellular regulation, leading to mineral-organic composites with hierarchical structures and properties optimized for their designated function. Such cellular regulation includes promoting mineralization at desired sites as well as inhibiting mineralization in soft tissues and other undesirable locations. In contrast, pathological mineralization, with potentially harmful health effects, can occur as a result of tissue or metabolic abnormalities, disease, or implantation of certain biomaterials. This progress report defines mineralization pathway components and identifies the commonalities (and differences) between physiological (e.g., bone remodeling) and pathological calcification formation pathways, based, in part, upon the extent of cellular control within the system. These concepts are discussed in representative examples of calcium phosphate-based pathological mineralization in cancer (breast, thyroid, ovarian, and meningioma) and in cardiovascular disease. In-depth mechanistic understanding of pathological mineralization requires utilizing state-of-the-art materials science imaging and characterization techniques, focusing not only on the final deposits, but also on the earlier stages of crystal nucleation, growth, and aggregation. Such mechanistic understanding will further enable the use of pathological calcifications in diagnosis and prognosis, as well as possibly provide insights into preventative treatments for detrimental mineralization in disease.

Clinical and seminal parameters associated with testicular microlithiasis and its severity in males from infertile couples

STUDY QUESTION

Is there an association of testicular microlithiasis (TM) and its severity with testicular dysfunction in men from infertile couples?

SUMMARY ANSWER

The presence of ≥5 testis microcalcifications per sonogram at the scrotal ultrasonography (US) of infertile males was associated with a more severe testicular dysfunction as compared to males with limited, or without, TM.

WHAT IS KNOWN ALREADY

TM, representing an incidental finding in the scrotal US, is associated with male infertility and a higher risk for testicular cancer as compared to that in infertile males without TM. Still, there are unresolved questions on the relation between TM severity and testicular dysfunction in infertile men, as well as on the identification of risk factors for TM.

STUDY DESIGN, SIZE, DURATION

This study was an observational, retrospective, case-control investigation involving males who underwent clinical evaluation, measurement of reproductive hormones, seminal analysis and scrotal US as part of diagnostic work-up for couple infertility at an andrology clinic, between January 2004 and December 2018. One hundred patients, out of the 2112 scored men, were found to have TM during the US evaluation. One hundred male partners from 100 infertile couples without TM, comprising the control group, were selected through a matched analysis by age and date of evaluation to reduce the confounding effect of both age and technique variability all along the long period of observation.

PARTICIPANTS/MATERIALS, SETTING, METHODS

TM was defined as limited TM (LTM) or classical TM (CTM), when the maximum number of hyperecogenic spots per sonogram was &lt;5 or ≥5, respectively. CTM, LTM and control groups were compared for clinical variables, serum levels of FSH, LH, and total testosterone, as well for semen parameters and scrotal US features.

MAIN RESULTS AND THE ROLE OF CHANCE

After the exclusion of cases with testicular nodules to eliminate the possible confounding effect of testis cancer on testicular dysfunction, cases with CTM showed a lower mean testis volume (P = 0.03) and a lower sperm concentration (P = 0.03) as compared to the other two groups. A higher FSH level was observed in the CTM group compared to the LTM group (P = 0.02) and in controls (P = 0.009). The multiple logistic regression analysis showed that only a smaller testicle volume exhibited an independent significant association with a higher odds of detecting CTM (odds ratio = 0.84, 95% CI: 0.75–0.94; P = 0.02). No significant differences were observed between groups in the prevalence of risk factors for testicular cancer, or in the prevalence of conditions associated with TM.

LIMITATIONS, REASONS FOR CAUTION

The retrospective design of the study did not allow conclusions to be drawn about the possible underlying links in the associations of TM with defective spermatogenesis.

WIDER IMPLICATIONS OF THE FINDINGS

Males from infertile couples who exhibit a reduced testicular volume should undergo scrotal US, independent of sperm parameters, to exclude CTM and, eventually, testis cancer, although the association of CTM and current or future testis cancer risk is not yet clear. Evidence is provided here demonstrating that the presence of LTM has no clinical relevance in males from infertile couples.

STUDY FUNDING/COMPETING INTEREST(S)

Investigation was funded by Ministero dell’Università e della Ricerca, PRIN 2018, Italy. The authors have not declared any competing interests.

TRIAL REGISTRATION NUMBER

N/A

Determination of cadmium induced acute and chronic reproductive toxicity with Raman spectroscopy

Cadmium (Cd) is one of the toxic heavy metals which is confirmed to be related to male sterile. Here, confocal Raman spectroscopy was employed to detect biomolecular composition and changes in testis under acute and chronic Cd treatment. Specific Raman shifts associated with mitochondria, nucleic acids, proteins, lipids, and cholesterol were identified which were distinguishing among groups undergoing different Cd treatment times. Supporting evidences were provided by conventional experimental detections. The relevant biochemical parameters, pathological changes, and protein expression related to testosterone synthesis were all changed and consistent with Raman spectrum information. In conclusion, confocal Raman spectroscopy presents a reliable data and provides a novel method which is expected to be a promising strategy in reproduction toxicity research.

Testicular Microlithiasis: Case Report and Current Knowledge

Sonographic evaluation is the gold standard in diagnosing of testicular microlithiasis, the nature of which has raised controversy in opinions regarding its premalignant or benign tendency. Testicular microlithiasis is often an incidental finding on sonographic examination with indications for other disease processes, and it may or may not require additional follow-up. This pathology has raised equal interest among domestic and foreign researchers, and studies have been performed on both adult and pediatric populations, yet there is no standard recommendation for follow-up care of testicular microlithiasis. Isolated testicular microlithiasis and that with additional risk factors may require different approaches to testing and care. In this publication, a case study is reviewed and two approaches to follow-up care of testicular microlithiasis based on the associated risk factors or a lack of thereof are discussed.

Testicular microlithiasis is associated with ethnicity and socioeconomic status

Background

There are limited studies about testicular microlithiasis (TML) and background information such as health, lifestyle, and socioeconomic status.

Purpose

To assess the prevalence of TML in relation to socioeconomic status and ethnicity.

Material and Methods

From a database of scrotal ultrasound examinations in a single institution, all men who underwent routine ultrasound examinations for a variety of symptoms from 1998 to 2015 were included. Skilled observers performed all examinations, and presence of any form of intra-testicular calcification, including TML, was recorded on the examination report and a representative image obtained and stored. A total of 1105 cases with TML were reviewed and random sample of 1105 controls from the same database was also reviewed. Demographics were recorded including ethnicity (white, black, and others) and socioeconomic groups (IMD Quintile).

Results

Black men had increased prevalence of TML (odds ratio [OR] = 2.17, 95% confidence interval [CI] = 1.72–2.75) compared with white men. Among the 1105 TML cases, 423 (38.3%) were white, 273 (24.7%) black, 152 (13.8%) had other ethnicities, and 257 (23.2%) had no ethnicity recorded. In the control group of 1105 men without TML, 560 (50.7%) were white, 171 (15.5%) black, 111 (10.0%) had other specified ethnicities, and 263 (23.8%) had no ethnicity recorded. Men from the most deprived socioeconomic groups had higher prevalence of TML than men in the most affluent groups, with a trend in OR from the least deprived to the most deprived group.

Conclusion

Pathogenesis and clinical relevance of TML is unknown but our results point towards possible ethnic and socioeconomic variation in the underlying causes of TML.

Prevalence of small testicular hyperechogenic foci in subgroups of 382 non-vasectomized, azoospermic men: a retrospective cohort study

Testicular hyperechogenic foci (THF) are associated with Klinefelter's syndrome, cryptorchidism, infertility, and testicular germ cell neoplasia. The aims of the study were to evaluate THF in relation to etiology of azoospermia and to Sertoli cell dysfunction. The structures inside the scrotum of consecutive non‐vasectomized, azoospermic were examined by ultrasonography, and hormone (FSH, LH, testosterone, and prolactin), and genetic analyses (karyotype, Y microdeletions, and CFTR mutations) were performed. At testicular ultrasonography, patients were graduated into: pronounced THF (>7 THF per transducer field), distributed universally (uTHF) or collected in plaques (pTHF), borderline THF (bTHF; 3–7 THF per transducer field), or no THF (<3 THF per transducer field). Diagnostic testicular biopsy was taken open or with TruCut needle (14G). THF status was sufficiently described in 382 of 449 potential participants, and testicular histology was available in 300 cases. Presence of ultrasonographically detectable THF was compared to presence of testicular microlithiasis (TM) detected histologically. Sertoli cell dysfunction was investigated in a subgroup using a three‐stage immunoperoxidase technique for detection of cytokeratin‐18 (CK‐18). The prevalence of THF was 13.4%. uTHF was found in 11 men (2.9%), the pattern was bilateral in four while other four had bTHF in the other testis. pTHF was detected in eight cases (2.1%), and except for one case with Klinefelter's syndrome, pTHF was in all cases occurring unilaterally. bTHF was detected in 32 cases (8.4%), bilaterally in 17 (53%). Pronounced THF was significantly associated with testicular malignancy. CK‐18 was detected in more azoospermic men with sperm production in ≤50% seminiferous tubules than in azoospermic men with spermatogenesis in ≥90% of seminiferous tubules and normal controls (p < 0.05). Unfortunately, TM detected histologically was not detected in any patient expressing THF, and neither THF nor TM was detected in any of the patients examined for CK‐18. Sertoli cell dysfunction was not associated with testicular microlithiasis or hyperechogenic foci.

Testicular Microlithiasis in the Setting of Primary Extragonadal Germ Cell Tumor: A Case Series

The clinical significance of testicular microlithiasis (TM) in patients with primary extragonadal germ cell tumor (EGCT) is not well understood. When EGCT is suspected, sonographic and physical examination of the testicles should be performed to evaluate for testicular lesion or atrophy; negative testicular ultrasound with current technology virtually excludes the possibility of occult primary lesion. Although EGCTs are known to be associated with elevated level of serum tumor markers, the utility of tumor markers in the presence of TM is not well understood. Current guidelines for TM follow-up and management do not include any potential correlation between TM and primary EGCT, an association that should be addressed on future updates.

How should we monitor boys with testicular microlithiasis?

Testicular microlithiasis (TM), a rare condition characterized by calcification within the seminiferous tubules, is associated with benign and malignant disorders of the testis. We review current practices of following up pediatric patients diagnosed TM incidentally on scrotal ultrasonography (US). We analyzed retrospectively patient characteristics, family history, indications for US, pathological features, US findings, outcome, and follow-up. At our institution, 2875 scrotal US examinations were performed on 2477 children with various scrotal complaints from 2008 to 2015. Testicular microlithiasis was detected in 81 patients (i.e., an incidence of 3.27%). Every 6 months, each patient underwent a clinical and ultrasonographic evaluation as well as serum tumor markers determination to detect a potential malignancy. Seventy-eight patients who had undergone scrotal US at least twice were included in this study. We evaluated the US studies for the type of TM (diffuse and focal) and change in follow-up studies. Testicular microlithiasis was typically diffuse (n = 56, 71.8%) and bilateral (n = 45, 57.7%), and it was detected the most frequently in the 9-11-year age group (27 patients, 34.6%). The most common comorbid conditions included undescended testes (31 patients, 39.7%) and hydrocele (11 patients, 14.1%). We found that serum tumor markers were within normal limits both at diagnosis and upon follow-up. No testicular tumors or new abnormal symptoms developed during the clinical follow-up. There is no convincing evidence that TM alone is premalignant in a pediatric population. In terms of follow-up, we advise regular self-examinations and annual US in the absence of risk factors.

Application of Raman spectroscopy in Andrology: non-invasive analysis of tissue and single cell

As a fast, label-free and non-invasive detection method, Raman spectroscopy has been widely used for the interrogation of biological tissues, any alterations of molecular structure and chemical components during pathological processes would be identified and revealed via the differences on Raman spectrum. In clinics, the Raman spectroscopy has great potentials to provide real-time scanning of living tissues and fast diagnosis of diseases, just like discrimination of various carcinomas. A portable Raman spectroscopy which combined Raman system with an optical fiber probe has also been developed and proved to be able to provide intraoperative assistance in both human study and animal models. In Andrology, interests in Raman spectroscopy had just emerged. In this review, we summarized the progress about the utility of Raman spectroscopy in Andrology, the literatures were gathered from PubMed and Ovid database using MeSH terms associated with prostate, testis, seminal plasma and single sperm cell. We also highlighted the serious challenges as to the final clinical application of Raman technique. In conclusion, research in Raman spectroscopy may herald a new era for Andrology.

Clinical and investigative applications of Raman spectroscopy in Urology and Andrology

Raman spectroscopy (RS) is an optical technique that allows for real-time interrogation of biologic tissues with chemical specificity. Using a diode laser, incident photons are scattered on the tissue of interest and the spectral wavelength output is a reflection of the tissues’ molecular fingerprint. Naturally, this technology has come into clinical usage to evaluate benign versus malignant tissue. Within the field of Urology, RS has seen tremendous growth as an optical biopsy tool for the real-time evaluation of diseases of the bladder, prostate, kidney, and testis. With such growing fervor for this emerging spectroscopic modality, we present a current summary of clinical studies utilizing RS within Urology and Andrology to highlight its potential applications.

Vitamin D and male reproduction

Vitamin D is a versatile signalling molecule with a well-established role in the regulation of calcium homeostasis and bone health. The spectrum of vitamin D target organs has expanded and the reproductive role of vitamin D is highlighted by expression of the vitamin D receptor (VDR) and enzymes that metabolize vitamin D in testis, male reproductive tract and human spermatozoa. The expression levels of VDR and CYP24A1 in human spermatozoa serve as positive predictive markers of semen quality, and VDR mediates a nongenomic increase in intracellular calcium concentration that induces sperm motility. Interestingly, functional animal models show that vitamin D is important for estrogen signalling and sperm motility, while cross-sectional studies support the positive association between serum 25-hydroxyvitamin D level and sperm motility in both fertile and infertile men. Expression of VDR and enzymes that metabolize vitamin D in fetal testis indicates a yet unknown role during development, which may be extrapolated from invasive testicular germ cell tumours where 1α,25-dihydroxyvitamin D induces a mesodermal differentiation of the pluripotent testicular cancer cells. Taken together, vitamin D signalling has a positive effect on semen quality, increases estrogen responsiveness and differentiates germ cell tumours. Future studies are needed to determine when 1α,25-dihydroxyvitamin D acts in a paracrine manner and whether systemic changes, which are subject to pharmacological modulation, could influence male reproductive function.

Raman microspectroscopy: shining a new light on reproductive medicine

BACKGROUND The last 20 years have seen an enormous upsurge in the number of publications reporting findings obtained by Raman spectroscopy, a non-invasive, non-destructive method which uses the inelastic scattering of light to provide a 'fingerprint' of the sample's chemical composition and constituents. Long neglected because of practical difficulties, the technique has been transformed by recent technological advances into a powerful analytical tool capable of opening avenues of investigation that were previously out of the reach of biomedical scientists. Beyond introducing the approach and describing its relative merits and weaknesses, the aim of this review is to provide a spur for discussion of what may become an invaluable tool for biomedical investigations. METHODS A comprehensive review of the literature was conducted searching PubMed and Ovid databases using numerous MeSH terms associated with reproductive medicine. Furthermore, the reference lists of all reported literature were explored. The searches were restricted to English language articles published in the last 50 years. RESULTS Beginning with simple characterizations of biologically and medically important substances, aided by increasing technological sophistication, the use of Raman spectroscopy in biomedicine has quickly expanded to the investigation of complex biochemical interactions, the assessment of organelles and now the evaluation of living cells and tissue. The first Raman investigations of reproductive organs were primarily oncological in nature; however, the past few years have seen an increase in the application of the technique for the assessment and evaluation of both male and female gametes. In particular, progress has been made in the characterization, identification and localization of sperm nuclear DNA damage. CONCLUSIONS The use of Raman spectroscopy has already provided many tantalizing glimpses into the potential that the technique has to answer many of the unresolved issues in investigative and therapeutic reproductive medicine. However, without stringent assessment and the clear representation of the methods' findings, their true meaning cannot be revealed nor should any conclusions be hastily derived. For the potential of Raman microspectroscopy to be truly realized, the dependability and reliability of the technique and its results can only be ascertained by multidisciplinary collaborations that undertake carefully conducted, controlled and analysed studies.

Testicular microlithiasis: is it significant?

Previously considered to be a benign finding on scrotal ultrasonography, testicular microlithiasis (TM) is now recognized as a condition associated with the development of testicular neoplasia. Despite this the management of TM remains unclear. We review the evidence for this association and suggested management strategies.

Testicular microlithiasis: is there a need for surveillance in the absence of other risk factors?

OBJECTIVE

Ultrasound surveillance of patients with testicular microlithiasis (TM) has been advocated following the reported association with testicular cancer. The aim of this study was to assess the evidence base supporting such surveillance.

METHODS

Formal literature review identified cohort studies comprising at least 15 patients followed up for at least 24 months. Combining an institutional audit with the identified studies in a pooled analysis the incidence of new cancers during the surveillance period was evaluated.

RESULTS

Literature review identified eight studies. Our institutional audit comprised 2,656 men referred for scrotal ultrasound. Fifty-one men (1.92 %) with TM were identified, none of whom developed testicular cancer (mean follow-up: 33.3 months). In a combined population of 389 men testicular cancer developed in 4. Excluding 3 who had additional risk factors, only 1 of 386 developed testicular cancer during follow-up (95 % CI 0.05-1.45 %).

CONCLUSIONS

Ultrasound surveillance is unlikely to benefit patients with TM in the absence of other risk factors. In the presence of additional risk factors (previous testicular cancer, a history of maldescent or testicular atrophy) patients are likely to be under surveillance; nonetheless monthly self-examination should be encouraged, and open access to ultrasound and formal annual surveillance should be offered.

KEY POINTS

• The literature reports a high association between testicular microlithiasis and testicular cancer. • Our study and meta-analysis suggest no causal link between microlithiasis and cancer. • In the absence of additional risk factors surveillance is not advocated. • In the presence of additional risk factors surveillance is recommended. • Such surveillance is primarily aimed at engaging patients in regular follow-up.

Raman spectroscopy and its urological applications

Purpose:

The Raman spectroscopic technology can be utilized for the detection of changes occurring at the molecular level during the pathological transformation of the tissue. The potential of its use in urology is still in its infancy and increasing utility of this technology will transform noninvasive tissue diagnosis. The Nobel laureate, Sir C.V. Raman is credited for the discovery of the principles of Raman spectroscopy.

Materials and Methods:

Applications of Raman spectroscopy in the bladder, renal, prostate, and other urological disorders were gathered from Medline and abstracts from recent international urological meetings. Current status and future directions of Raman spectroscopy in urology were also reviewed.

Results:

Raman spectroscopic technology is used to interrogate biological tissues. The potential use of this technology in urology has shown encouraging results in the in vitro diagnosis and grading of cancers of the bladder and the prostate. Raman microprobes have been used for the characterization and identification of renal lithiasis. Technology may be available for the urologists to determine the margin status intraoperatively during partial nephrectomy and radical prostatectomy. The future would see the development of optical fiber probes to incorporate them into catheters, endoscopes, and laparoscopes that will enable the urologist to obtain information during the operation.

Conclusion:

Raman spectroscopy is an exciting tool for real-time diagnosis and in vivo evaluation of living tissue. The potential applications of Raman spectroscopy may herald a new future in the management of various malignant, premalignant, and other benign conditions in urology.

Clinical update on testicular microlithiasis

PURPOSE OF REVIEW

Testicular microlithiasis becomes a greater interdisciplinary issue among urologists, andrologists, gynecologists dedicated to reproductive medicine, pediatricians, radiologists and pathologists. Proposed management ranges from benign neglect, instructing self-examination over follow-up once, regular biannual follow-up including ultrasonography to bilateral testicular biopsy to rule out possible concomitant unclassified intratubular germ cell neoplasia (ITGCN) or future development of testicular cancer. The aim of this review is to present an overview of the current dilemma and summarize management trends based on the most recent data.

RECENT FINDINGS

Testicular microlithiasis is not a premalignant condition but may accompany ITGCN or testicular cancer. The importance of ruling out ITGCN with testicular biopsy in high-risk men, such as in those with bilateral testicular microlithiasis, infertility, cryptorchidism, atrophic testes or contralateral testicular cancer, has been recently advocated.

SUMMARY

Despite greater awareness of testicular microlithiasis, a clear definition is currently missing and the etiology is still obscure. This causes confusion in management and follow-up. Self-examination alone or in combination with testicular ultrasonography has been advised. Recently, a single set of biopsies in selected, high-risk groups has been proposed to rule out ITGCN without a need for further investigations apart from self-examination. However, the cost-effectiveness of such a strategy needs to be evaluated.

Testicular microlithiasis and carcinoma in situ overview and proposed clinical guideline

Testicular microlithiasis (TM) has been associated with testicular germ cell tumours (TGCTs) in adolescents and adults and with its precursor carcinoma in situ (CIS). A clear definition of TM and the need for further diagnostics and follow-up is lacking. We reviewed the literature of TM and its association with TGCT/CIS and current follow-up advises and propose a management approach based on associated risk factors for TGCT. In the literature, a wide variance of TM incidence is reported in different patient populations. A consensus concerning the malignant potential of TM has not been reached. In addition, a clear definition on TM is lacking. Although a correlation between TM and TGCT or CIS is found, precise management and follow-up schedules are absent. We suggest that all hyperechogenic foci smaller than 3 mm without shadowing should be named TM irrespective of their number. In addition, we suggest a management scheme for physicians encountering TM in daily practice. Our algorithm suggests taking a testicular biopsy in a selected patient population with at least one additional risk factor for TGCT. A long-term active follow-up schedule, including ultrasonography and physical examinations, is not indicated in the remaining patients with TM.

Spectroscopic View of Life and Work of the Nobel Laureate Sir C.V. Raman

Raman spectroscopic and microscopic techniques have been used for nondestructive characterization of tissues and to differentiate benign and malignant tissues. The discovery of the principles of spectroscopy is credited to Sir C.V. Raman of India, who in 1930 brought the Nobel Prize in Physics to the East side of Suez. We present the life and work of Sir C.V. Raman with brief review of the uses of Raman spectroscopy in urology.

Mutations in SLC34A2 cause pulmonary alveolar microlithiasis and are possibly associated with testicular microlithiasis

Pulmonary alveolar microlithiasis (PAM) is a rare disease characterized by the deposition of calcium phosphate microliths throughout the lungs. We first identified a PAM locus by homozygosity mapping to 4p15, then identified, by a candidate-gene approach, the gene responsible for the disease as SLC34A2 (the type IIb sodium-phosphate cotransporter gene), which is involved in phosphate homeostasis in several organs. We identified six homozygous exonic mutations in the seven unrelated patients with PAM we studied. Three of the mutations were frameshifts, one was a chain termination, one was an amino acid substitution, and one was a deletion spanning the minimal promoter and the first exon. Absence of functional protein product of the gene is compatible with calcium phosphate deposition in alveolar airspaces. We show that impaired activity of the phosphate transporter is presumably responsible for the microliths and that PAM is a recessive monogenic disease with full penetrance. Testicular microlithiasis (TM) is a disease that is more common than PAM. It is often associated with cancer and infertility. Since the gene we identified is also expressed in testis, we searched for mutations in subjects with TM. In 2 of the 15 subjects with TM we studied, we identified two rare variants, one synonymous and the other noncoding, that are possibly associated with the condition.

Identification of single eukaryotic cells with micro-Raman spectroscopy

For a fast identification of eukaryotic cells such as yeast species without a cultivation step it should be possible to perform the investigation on only one single cell. Since yeasts as eukaryotes are heterogeneous and their Raman spectra are therefore dependent on the measuring position, one Raman spectra is not representative of the whole cell. In this contribution we demonstrate the application of average Raman spectra of a line scan over single yeast cells. These average spectra are used for classification with the help of a support vector machine.

Identification of chemical compositions of skin calcified deposit by vibrational microspectroscopies

Calcinosis cutis is characterized by the deposition of calcium salts in the subcutaneous tissues. Both Fourier transform infrared (FTIR) and Raman microspectroscopic analysis have been applied to easily get the chemical compositions of the skin calcified deposit (SCD), which was surgically excised from a female patient. This SCD was cut into two parts for histopathological (H&E stain) examination and vibrational microspectroscopic study. The result indicates that the whole SCD in the skin lesion was found to be a well-developed, mature and hard mass. Several FTIR absorption bands at 873, 961 and 1,031 cm(-1) [the stretching modes of carbonate and phosphate of hydroxyapatite (HA)], 1,547 and 1,658 cm(-1) (the amide I and II bands of collagen) were detected in the IR spectrum of SCD. The Raman spectral bands at 1,665 and 1,450 cm(-1) (collagen); 1,519 and 1,156 cm(-1) (beta-carotene); and 1,072 and 958 cm(-1) (HA) were also obtained. To our knowledge, this is the first report using FTIR and Raman microspectroscopies to quickly identify and quantify three predominant components, collagen, beta-carotene and type B carbonated HA, in the SCD of a patient.

Testicular Microlithiasis in Association with Pseudoxanthoma Elasticum

PURPOSE

To determine the presence of testicular microlithiasis in male subjects with pseudoxanthoma elasticum (PXE).

MATERIALS AND METHODS

Institutional review board approval was obtained for the prospective and retrospective components of this HIPAA-compliant study. Informed consent was obtained from all patients or their parents. Testicular ultrasonography (US) was performed in eight men aged 29-56 years and in one 13-year-old boy, all with confirmed PXE. Two radiologists reviewed the US images by consensus for testicular microlithiasis, testicular masses, and additional testicular abnormalities. Testicular microlithiasis was judged to be classic when at least five microliths were seen on a single US image and to be limited when fewer than five microliths were seen on all obtained US images. Urologic physiologic examinations were performed. A history and/or symptoms of testicular disease also were recorded at the time of examination. Similarly, the testicular US images obtained in two additional men, aged 48 and 59 years, and in another 13-year-old boy were retrospectively reviewed. Histopathologic testicular analysis was performed in one autopsy case.

RESULTS

Of the 12 participants, 11 (92%) had classic and one (8%) had limited testicular microlithiasis. None of the 12 participants had evidence of testicular malignancy at US or physical examination. Histopathologic analysis at autopsy revealed intratubular microlithiasis without the calcification of elastic fibers in arterial walls that is characteristic of cutaneous PXE.

CONCLUSION

Study findings suggested an association between PXE and testicular microlithiasis. It is possible that the testicular microlithiasis in male subjects who have PXE is related to the underlying PXE abnormality.