Central precocious puberty should be taken seriously in children with Leydig cell tumors of the testis after surgical treatment: a tertiary center experience.

ABSTRACT: Central precocious puberty secondary to Leydig cell tumors is rare in children. We retrospectively analyzed the mid- to long-term follow-up data of patients with Leydig cell tumors. The clinical data of 12 consecutive patients who were treated at Beijing Children's Hospital, Capital Medical University (Beijing, China), between January 2016 and October 2023 were retrospectively reviewed. Clinical evaluations, including physical examination, hormone examination, serum tumor marker analysis, abdominal and scrotal ultrasound, chest X-ray, and bone age measurement, were conducted before surgery and at follow-up time points. Surgical approaches were selected according to the individual conditions. Patients with an abnormal hormonal status and suspected of having central precocious puberty were referred to endocrinologists to confirm the diagnosis. Subsequently, gonadotropin-releasing hormone analog therapy was proposed. The mean patient age was 81.3 (range: 40-140) months at the time of the operation. Ten patients had peripheral precocious puberty at admission. All patients had elevated preoperative testosterone levels, whereas tumor marker levels were normal. Testis-sparing surgery was performed in eleven patients, and radical orchiectomy was performed in one patient. The follow-up duration (mean ± standard deviation) was 36.2 ± 25.3 months. Five patients had central precocious puberty, with a mean duration of 3.4 (range: 1-6) months postoperatively. Three patients were receiving gonadotropin-releasing hormone analog therapy, and good suppression of puberty was observed. No risk factors were found for secondary central precocious puberty. There was a high prevalence of central precocious puberty secondary to Leydig cell tumors in our study. Gonadotropin-releasing hormone analog therapy has satisfactory treatment effects. Larger sample sizes and long-term follow-up are needed in future studies.

Tumor de células de leydig ovariano em paciente pós-menopausa: relato de caso / Ovarian leydig cell tumor in a postmenopausal patient: case report tumor de células de leydig / Ovárico en una paciente posmenopáusica: informe de un caso

Introdução: O tumor de células de Leydig é uma neoplasia estromal pura do ovário, caracterizada pela produção de hormônios esteroides. As lesões podem ser pequenas e restritas ao ovário, mas podem causar sintomas de hiperandrogenismo e virilização. Objetivo: Trata-se de um relato de caso de uma paciente com tumor de células de Leydig ovariano, suas repercussões clínicas e condutas tomadas frente a este caso. Método: Estudo observacional e retrospectivo baseado em único caso de tumor de células de Leydig do Serviço de Patologia do Hospital Emílio Carlos. As fontes de coleta de dados envolveram os prontuários e laudos de exames fornecidos pelo respectivo serviço. Resultados: Mulher de 83 anos foi encaminhada ao serviço de oncologia devido a lesões uterinas em ultrassonografia. Solicitados marcadores tumorais, incluindo CA-125, cuja dosagem seriada se mostrou ascendente. Proposta cirurgia para histerectomia total e salpingo-ooforectomia bilateral, que ocorreu sem intercorrências. Exame histopatológico identificou um útero com nódulos intramurais compatíveis com leiomiomas uterinos. No entanto, o ovário direito mostrou a presença de uma neoplasia estromal, medindo cerca de 1,0 x 0,8 cm, composta por células poligonais com citoplasma grande, eosinofílico e granular. O estudo imuno-histoquímico evidenciou que a lesão era positiva para inibina alfa e calretinina e FOXL2 era negativo. Os achados histopatológicos e imuno-histoquímicos em conjunto permitiram o diagnóstico de tumor de células de Leydig do ovário. Conclusão: Embora um diagnóstico raro, o tumor de células de Leydig do ovário deve ser um importante diagnóstico diferencial entre as neoplasias ovarianas em mulheres na pós-menopausa

Introduction: Leydig cell tumor is a pure stromal neoplasm of the ovary, characterized by the production of steroid hormones. The lesions can be small and restricted to the ovary, but can cause symptoms of hyperandrogenism and virilization. Objective: This is a case report of a patient with ovarian Leydig cell tumor, its clinical repercussions and the procedures taken in this case. Method: An observational and retrospective study based on a single case of Leydig cell tumor from the Pathology Department of the Emílio Carlos Hospital. The sources of data collection involved the medical records and examination reports provided by the respective service. Results: An 83-year-old woman was referred to an oncology service due to uterine lesions on ultrasound. Tumor markers were requested, including CA-125, whose serial dosage showed an increase. Surgery was proposed for total hysterectomy and bilateral salpingo-oophorectomy, which took place uneventfully. Histopathological examination identified a uterus with intramural nodules compatible with uterine leiomyomas. However, the right ovary showed the presence of a stromal neoplasm, measuring around 1.0 x 0.8 cm, composed of polygonal cells with large, eosinophilic and granular cytoplasm. The immunohistochemical study showed that the lesion was positive for alpha inhibin and calretinin and FOXL2 was negative. The histopathological and immunohistochemical findings together allowed the diagnosis of Leydig cell tumor of the ovary. Conclusion: Although a rare diagnosis, ovarian Leydig cell tumor should be an important differential diagnosis among ovarian neoplasms in postmenopausal women

Introducción: El tumor de células de Leydig es una neoplasia estromal pura del ovario, caracterizada por la producción de hormonas esteroideas. Las lesiones pueden ser pequeñas y restringidas al ovario, pero pueden causar síntomas de hiperandrogenismo y virilización. Objetivo: Este es un reporte de caso de una paciente con tumor de células de Leydig de ovario, sus repercusiones clínicas y las acciones tomadas en este caso. Método: Estudio observacional y retrospectivo basado en un único caso de tumor de células de Leydig procedente del Servicio de Anatomía Patológica del Hospital Emílio Carlos. Las fuentes de recogida de datos fueron las historias clínicas y los informes de exploración del respectivo servicio. Resultados: Mujer de 83 años fue remitida a servicio de oncología por presentar lesiones uterinas en la ecografía. Se solicitaron marcadores tumorales, como CA-125, cuyo dosaje seriado mostró un aumento. Se propuso cirugía de histerectomía total y salpingooforectomía bilateral, que se realizó sin incidencias. El examen histopatológico identificó un útero con nódulos intramurales compatibles con leiomiomas uterinos. Sin embargo, el ovario derecho mostraba la presencia de neoplasia estromal, de aproximadamente 1,0 x 0,8 cm, compuesta por células poligonales con citoplasma grande, eosinófilo y granular. El estudio inmunohistoquímico demostró positividad para la alfa inhibina y la calretinina y que la FOXL2 era negativa. Los hallazgos histopatológicos e inmunohistoquímicos en conjunto permitieron el diagnóstico de tumor de células de Leydig de ovario. Conclusión: Aunque se trata de un diagnóstico infrecuente, el tumor de células de Leydig del ovario debe ser un importante diagnóstico diferencial entre las neoplasias ováricas en mujeres posmenopáusicas.

Human benign Leydig cell tumor - Biochemical evaluation.

Recently we reported expressional alterations in 219 genes and their transcripts in Leydig cell tumors but nowadays there is still a lack of full basic biochemical characteristics of these tumors. The discovery of potential biochemical markers for tumor management from early detection, treatments, and control of therapy results may markedly supplement genetic data. Leydig cell micronodules were obtained from patients with azoospermia who were qualified for testicular biopsy. The biochemistry of Leydig cell tumors was analyzed using histological staining and spectrophotometric measurements of total proteins, carbohydrates, lipids, and nucleic acids. In addition, the levels of calcium (Ca2 +), copper (Cu2 +), zinc (Zn2 +), and selenium (Se2 +) ions were measured. When compared to healthy testis we revealed, for the first time, that in the interstitial tissue with Leydig cell tumors, great amounts of proteins, carbohydrates, lipids, and acids were dislocated from the seminiferous tubules. Measurements of organic compounds showed a decrease (P < 0.05) only in the Cu2 + content in Leydig cell tumors which may be related to their altered biochemical structure. This specific result may be promising for designing further approaches to manage this tumor based on combining morphological and molecular data.

Ultrasound contrast-enhanced diagnosis of testicular Leydig cell tumor: A case report and literature review.

Leydig cell tumor (LCT) is a rare testicular tumor. We report a case of an elderly male patient who discovered a left testicular mass during a regular health examination four years ago. The patient did not experience any significant discomfort and opted for regular follow-up visits. During the most recent visit, we performed routine ultrasound and contrast-enhanced ultrasound (CEUS) examinations. By observing the lesion's location, echogenicity, margins, vascular distribution, as well as the rapid enhancement and slow washout characteristics on contrast-enhanced ultrasound, we arrived at a diagnosis of LCT. Subsequently, the patient underwent left inguinal orchiectomy. Postoperative pathology and immunohistochemistry confirmed the diagnosis of LCT. Additionally, we conducted a comprehensive review of LCT-related literature from PubMed and SCOPUS, summarizing the clinical features, follow-up duration, prognosis, and ultrasound characteristics associated with LCT.

ß-Catenin alterations in testicular Leydig cell tumour: a immunohistochemical and molecular analysis.

BACKGROUND: Testicular Leydig cell tumours (LCTs) are the most common type of sex cord-stromal tumour in men, representing 1%-3% of all testicular neoplasms. Among testicular sex cord-stromal tumours, CTNNB1 mutations and nuclear expression of ß-catenin have been typically associated with Sertoli cell tumour. Recent genomic analyses have shown that CTNNB1 variants are also identified in a subset of LCTs; however, the frequency and clinicopathologic associations of ß-catenin alterations remain incompletely understood in this tumour type. METHODS: In this study, we evaluated 32 LCTs (five malignant/metastasizing, 27 nonmetastasizing) using ß-catenin immunohistochemistry and DNA sequencing. RESULTS: Immunohistochemistry revealed focal or multifocal nuclear ß-catenin expression in 47% of the tumours. Diffuse nuclear ß-catenin expression (in >50% of the tumour cells) was not detected in any of the cases analysed herein. Comparison of ß-catenin-positive and ß-catenin-negative cases did not show significant differences in the frequency of adverse histopathologic findings or malignant clinical behaviour. DNA sequencing performed de novo on a subset of seven cases revealed the presence of exon 3 CTNNB1 variants in four of them (4/7, 57%), with variant allele frequencies (VAF) ranging from 7 to 33%. Two additional ß-catenin-positive cases that had been sequenced as part of a previous study harboured exon 3 CTNNB1 variants at VAF of 28% and 7%, respectively. CONCLUSION: These results demonstrate that ß-catenin alterations are relatively common in LCT, most likely occurring as subclonal events that are not enriched in cases with aggressive features. Further studies are needed to clarify the oncogenic role of ß-catenin in this tumour type.

Suspected renal interstitial cell tumor causing polycythemia in two dogs.

Here we report a case series of two dogs diagnosed as renal interstitial cell tumor (RICT) accompanied by elevated serum erythropoietin level and marked polycythemia. RICT is a rare tumor in dogs, originating from renal interstitial cells. While several renal tumors such as renal lymphoma, adenocarcinoma, carcinoma, sarcoma, fibrosarcoma and nephroblastoma may cause polycythemia, polycythemia caused by RICT has never been reported in dogs. The tumors in both dogs were solitary and lied within cortex or cortico-medullary junction. Histopathology revealed spindle-shaped cells suggesting mesenchymal origin, with no mitotic figures suggesting that the tumors in both dogs were benign. Following surgical removal of the affected kidney, serum erythropoietin level and polycythemia normalized in both dogs.

Ovarian Leydig Cell Tumor Associated with Recurrent Torsion and Virilization in an Adolescent Patient.

Ovarian tumors are rare in children; however, their incidence increases with age. Of these ovarian tumors, Leydig cell tumors are some of the rarest, accounting for less than 0.1% of all ovarian tumors across all ages. Leydig cell tumors predominantly occur in postmenopausal women and are characterized by nodular proliferation of Leydig cells in the ovarian hilum with intracytoplasmic Reinke crystals. These tumors secrete androgens, which can disrupt ovarian function, clinically presenting with abnormal uterine bleeding and virilization. Although they are generally benign, current recommendations are for treatment with a unilateral salpingo-oophorectomy. In adolescents, hyperandrogenism is most commonly caused by polycystic ovarian syndrome (PCOS); however, the differential for hyperandrogenism is broad. We present a case of a 15-year-old girl with a history of primary amenorrhea who presented with a Leydig cell tumor associated with recurrent ovarian torsion and virilization. This case reviews the challenges with diagnosis, management, and future implications of a rare androgen-secreting tumor in young patients.

Two Rare Cases of Paratubal Leydig Cell Nodules: Clinical Relevance and Debated Terminology of a Noteworthy Incidentaloma.

Cells with cytologic and immunohistochemical features of Leydig cells are normally present in the ovary and the ovarian hilum, are testosterone-producing, and have been referred to as ovarian hilus cells. Rarely these cells form nests or nodules in extraovarian sites such as the mesovarium or mesosalpinx. Because they are so rare, these nodules can present a diagnostic challenge when first encountered. This report describes 2 such incidental nodules in the mesosalpinx associated with a small paratubal cyst and suggests that the term Leydig cell nodule be preferred over the nonspecific and confusing historical term ovarian hilus cell nest.

Ovarian Leydig Cell Tumor and Ovarian Hyperthecosis in a Postmenopausal Woman: A Case Report and Literature Review.

Ovarian Leydig cell tumor is a rare type of ovarian steroid cell neoplasms, presenting in only 0.1% of all ovarian tumor cases, and is generally androgen-secreting and unilateral. Although they are often malignant non-spreading tumors, which have excellent prognosis, benign ovarian Leydig cell tumors with low-risk malignancy can be also detected. Ovarian hyperthecosis is a rare non-neoplastic disorder, in most cases bilateral. Ovarian tumors and ovarian hyperthecosis are one of the main causes of hyperandrogenism in postmenopausal women, a condition strongly associated with both hormonal and metabolic changes. Here, we report a 65-year-old patient with complaints of excessive body hairiness and alopecia. The laboratory investigation showed increased levels of serum testosterone and dehydroepiandrosterone sulfate (DHEA-S). Imaging, including transvaginal ultrasound and pelvic MRI revealed the presence of two masses in the ovaries. The patient underwent a laparoscopic bilateral salpingo-oophorectomy due to the ovarian tumors unknown etiology, and histopathological examination revealed a unilateral benign left ovarian Leydig cell tumor with bilateral ovarian stromal hyperplasia and ovarian hyperthecosis. Making differential diagnosis between ovarian tumors and ovarian hyperthecosis is difficult. Bilateral salpingo-oophorectomy is the treatment of choice in postmenopausal women with benign Leydig cell ovarian tumor, as well as ovarian hyperthecosis, as it offers both a cure and diagnostic confirmation.

Leydig cell tumor of the testis with characteristic contrast patterns of tumor and non-tumorous testicular parenchyma on MRI: a case report.

PURPOSE: Testicular Leydig cell tumor (LCT) is a rare subtype of testicular neoplasms that occurs in the interstitial tissue of testes, accounting for 1-3% of total testicular masses removed annually. We report a case of 70-year-old man diagnosed as testicular LCT. This report demonstrates a testicular LCT with intratumoral and non-tumorous testicular parenchymal enhancement in the affected testis, which should be considered characteristic findings of LCT. METHODS: Ultrasonography showed a hypoechoic mass. On magnetic resonance imaging, the tumor showed low signal intensity comparable to the surrounding testicular tissue on T1-weighted images (T1WI) and low signal intensity on T2-weighted images (T2WI). On gadolinium contrast-enhanced T1WI (CE-T1WI), the tumor showed a rapid and marked wash-in and subsequent prolonged washout. The spared, non-tumorous testicular parenchyma showed slow and progressive enhancement in the early phase, which was as strong as or stronger than that of the mass in the delayed phase. The patient underwent right orchiectomy. RESULTS: Pathologically, the tumor was diagnosed as a testicular Leydig cell tumor (LCT). Leydig cell proliferation was observed with well-developed microvessels, atrophy of the seminiferous tubules, and stromal edema in the non-tumorous testicular parenchyma. Leydig cells in the non-tumorous parenchyma were positive for estrogen receptors. CONCLUSION: Since the contrast findings in the non-tumorous testicular parenchymal region on CE-T1WI likely match the histopathological features of LCT, our case suggests that the presence of non-tumorous testicular parenchymal enhancement on imaging might indicate a diagnosis of LCT.

Utilization of NKX3.1, P501S, Prostate-Specific Antigen, and Steroidogenic Factor 1 to Distinguish Malignant Leydig Cell Tumor From Metastatic Prostatic Adenocarcinoma to the Testis.

CONTEXT.­: A recent study demonstrated that NKX3.1-positive staining can uncommonly be seen in testicular Sertoli cell tumors (1 of 4 cases). Also, it was reported that 2 of 3 Leydig cell tumors of the testis showed diffuse cytoplasmic staining for P501S, although it was unclear whether it was specific granular staining that defines true positivity. However, Sertoli cell tumors do not typically pose a diagnostic dilemma with metastatic prostate carcinoma to the testis. In contrast, malignant Leydig cell tumors, which are exceedingly rare, can closely resemble Gleason score 5 + 5 = 10 prostatic adenocarcinoma metastatic to the testis. OBJECTIVE.­: To evaluate the expression of prostate markers in malignant Leydig cell tumors and steroidogenic factor 1 (SF-1) in high-grade prostate adenocarcinoma, as no data are currently published on these topics. DESIGN.­: Fifteen cases of malignant Leydig cell tumor were collected from 2 large genitourinary pathology consult services in the United States from 1991 to 2019. RESULTS.­: All 15 cases were negative immunohistochemically for NKX3.1, and all 9 with available additional material were negative for prostate-specific antigen and P501S and positive for SF-1. SF-1 was negative immunohistochemically in a tissue microarray with cases of high-grade prostatic adenocarcinoma. CONCLUSIONS.­: The diagnosis of malignant Leydig cell tumor and its distinction from metastatic adenocarcinoma to the testis can be made immunohistochemically on the basis of SF-1 positivity and negativity for NKX3.1.

cAMP-specific phosphodiesterase 8A and 8B isoforms are differentially expressed in human testis and Leydig cell tumor.

Cyclic adenosine monophosphate/Protein kinase A (cAMP/PKA) signaling pathway is the master regulator of endocrine tissue function. The level, compartmentalization and amplitude of cAMP response are finely regulated by phosphodiesterases (PDEs). PDE8 is responsible of cAMP hydrolysis and its expression has been characterized in all steroidogenic cell types in rodents including adrenal and Leydig cells in rodents however scarce data are currently available in humans. Here we demonstrate that human Leydig cells express both PDE8A and PDE8B isoforms. Interestingly, we found that the expression of PDE8B but not of PDE8A is increased in transformed Leydig cells (Leydig cell tumors-LCTs) compared to non-tumoral cells. Immunofluorescence analyses further reveals that PDE8A is also highly expressed in specific spermatogenic stages. While the protein is not detected in spermatogonia it accumulates nearby the forming acrosome, in the trans-Golgi apparatus of spermatocytes and spermatids and it follows the fate of this organelle in the later stages translocating to the caudal part of the cell. Taken together our findings suggest that 1) a specific pool(s) of cAMP is/are regulated by PDE8A during spermiogenesis pointing out a possible new role of this PDE8 isoform in key events governing the differentiation and maturation of human sperm and 2) PDE8B can be involved in Leydig cell transformation.

Chlorinated organophosphorus flame retardants-induced mitochondrial abnormalities and the correlation with progesterone production in mLTC-1 cells.

Environmental monitoring data have indicated that three chlorinated organophosphorus flame retardants (Cl-OPFRs), including tris(2-chloroethyl)-phosphate (TCEP), tris(2-chloropropyl)-phosphate (TCPP), and tris(1,3-dichloro-2-propyl)-phosphate (TDCPP) are the predominant chemicals in various environmental matrices and exhibit reproductive endocrine disrupting activities. Currently, mitochondrial abnormality is a new paradigm for evaluating chemical-mediated cell dysfunction. However, a comprehensive correlation between these two aspects of Cl-OPFRs remains unclear. In this research, the effects of TCEP, TCPP, and TDCPP on progesterone production and mitochondrial impairment were investigated by using mouse Leydig tumor cells (mLTC-1). The half maximal inhibitory concentration (IC50) values at 48 h exposure indicated that the rank order of anti-androgenic activity was TDCPP > TCPP. Whereas, TCEP exhibited elevation of progesterone production. At concentrations close to IC50 of progesterone production by TCPP and TDCPP, the elevation of intracellular reactive oxygen species (ROS), depletion of mitochondrial membrane potential (MMP), reduction of cellular adenosine triphosphate (ATP) content, and alteration of mitochondrial structures was observed. In addition, the expression of main genes related to progesterone synthesis was dramatically down-regulated by TCPP and TDCPP treatments. These results imply that the inhibition effect of TCPP and TDCPP on progesterone production might be related to mitochondrial damage and down-regulated steroidogenic genes.

Histidine decarboxylase inhibitors: a novel therapeutic option for the treatment of leydigioma.

Recent reports indicate an increase in Leydig cell tumor (LCT) incidence. Radical orchiectomy is the standard therapy in children and adults, although it entails physical and psychosocial side effects. Testis-sparing surgery can be a consideration for benign LCT of 2.5 cm or less in size. Malignant LCTs respond poorly to conventional chemotherapy, so new treatment modalities are needed. In this study, we observed increased histidine decarboxylase expression and pro-angiogenic potential in LCT surgically resected from pediatric patients (fetal to pubertal) vs control samples from patients without endocrine or metabolic disorders which were collected at necropsy. We, therefore, evaluated for the first time the antitumor efficacy of two histidine decarboxylase inhibitors (α-methyl-dl-histidine dihydrochloride (α-MHD) and epigallocatechin gallate (EGCG)), alone and combined with carboplatin, in two preclinical models of LCT. MA-10 and R2C Leydig tumor cells, representing two different LCT subtypes, were used to generate syngeneic and xenograft mouse LCT models, respectively. In the syngeneic model, monotherapy with α-MHD effectively reduced tumor growth and angiogenesis. In the xenografts, which showed co-expression of histidine decarboxylase and CYP19, the combination of EGCG plus carboplatin was the most effective therapy, leading to LCT growth arrest and undetectable levels of plasmatic estradiol. Testicular and body weights remained unaltered. On the basis of this study, histidine decarboxylase may emerge as a novel pharmacological target for LCT treatment.

Is testis sparing surgery safe in patients with incidental small testicular lesions referring to a fertility center? A retrospective analysis reporting factors correlated to malignancy and long-term oncological outcomes.

PURPOSE: To define predictors of malignancy after Testis sparing surgery (TSS) in patients referring to a fertility center with incidental small testicular lesions. Sub analyses were performed to assess predictors of Leydig cell hyperplasia and Leydig cell tumor. MATERIALS AND METHODS: We performed a retrospective analysis of a single institutional database including patients treated with TSS between 2002 and 2020. All patients who underwent TSS as a first line surgical approach for incidentally detected lesions found during fertility evaluation were included. RESULTS: Data of 64 patients were collected. The median follow up was 58 months and no recurrences were observed. At univariable logistic regression multifocal lesions, hypervascularization, microlithiasis, age and lesion size were significantly associated with malignancy. At multivariable logistic regression lesion dimension, hypervascularization and multifocal lesions were predictors of malignancy. Lesions smaller than 5 mm proved to be benign in 96.6% of the cases (32/33). Intraoperative color of the lesion and US pattern of vascularization were predictors at multivariable logistic regression for Leydig cell hyperplasia and Leydig cell tumor. CONCLUSION: Ultrasonographic characteristics and intraoperative appearance of the lesion can predict the malignant nature of small testicular lesions, guiding their surgical management in patients referring to a fertility center. Based on our experience, clinicians may safely perform TSS in carefully selected patients.

Hyperandrogenism due to ovarian Leydig cell tumour presenting with polycythaemia.

A postmenopausal woman in her 60s was referred due to an elevated haemoglobin value found during her annual check-up. On physical examination, characteristic features of hyperandrogenism were observed which were not earlier mentioned. Laboratory investigations revealed polycythaemia accompanied by a normal erythropoietin and a negative analysis for JAK2-V617F mutation. A disproportionally and markedly elevated testosterone in combination with normal levels of adrenal androgens raised the suspicion of an ovarian source. CT scan showed nodular hyperdense lesions in both ovaries. A bilateral oophorectomy was performed and histological evaluation unfolded a Leydig cell ovarian tumour. Testosterone levels and haematological parameters normalised after surgery. Polycythaemia secondary to hyperandrogenism in postmenopausal women is an extremely rare condition and patients should be carefully analysed for the presence of androgen-secreting neoplasms. Diagnosis of the underlying pathology requires careful history, physical examination and comprehensive investigation. Treatment for this condition is surgery and resolves polycythaemia.

Multiparametric ultrasound for the diagnosis of Leydig cell tumours in non-palpable testicular lesions.

BACKGROUND: The widespread use of ultrasonography has led to an increased number of incidentally detected small non-palpable lesions, with Leydig cell tumours representing the majority of them. OBJECTIVES: The ultrasonography, real-time elastography and contrast-enhanced ultrasonography features of a large series of non-palpable testicular lesions were evaluated, focusing on the differences between Leydig cell tumours and other testicular masses. MATERIALS AND METHODS: Of the 4679 testicular ultrasonography examinations performed at the Authors' Institution between January 2009 and December 2018, 78 patients (1.7%) were incidentally diagnosed with at least one non-palpable lesion and were enrolled. Thirteen patients (16.6%) declined surgery and were thus excluded. The remaining 65 underwent surgical resection with frozen section analysis. The conventional ultrasonography, colour Doppler, real-time elastography and contrast-enhanced ultrasonography were performed by a radiologist having more than 10 years of experience. Demographic and clinical data were collected. RESULTS: Leydig cell tumours were detected in 32 patients, being the most frequent benign tumours (49.2%); of the non-Leydig cell tumours, 25 patients had malignant tumours, five non-neoplastic lesions and three other benign tumours. The Leydig cell tumour group had mostly infertility problems whereas the non-Leydig cell tumour group frequently experienced pain (p < 0.001). Leydig cell tumours were all hypoechoic (32/32, 100%; p = 0.002), more frequently presented with well-defined margins compared to non-Leydig cell tumours (30/32, 93.8% vs. 19/33, 57.6%; p = 0.001) and tended to be smaller than non-Leydig cell tumours (5.3 mm [standard deviation 2.7 mm] vs. 10.6 mm [standard deviation 3.8 mm], respectively; p < 0.001). The vascular pattern characterised by the rapid wash-in followed by the delayed wash-out observed during contrast-enhanced ultrasonography was significantly associated with the Leydig cell tumour histological diagnosis, even at multivariate analysis (odds ratio 480.5, p < 0.001), and yielded a high diagnostic accuracy (area under the receiver operating characteristic curve 0.954, 95% confidence interval 0.903-1). DISCUSSION: Contrast-enhanced ultrasonography demonstrated high diagnostic accuracy in identifying benign testicular lesions, such as Leydig cell tumours; they are the most common non-palpable tumours detected in infertile men and may benefit from enucleation.

Precocious puberty related to Leydig cell testicular tumor: the diagnostic imaging keys.

BACKGROUND: We report the challenging case of a 6-year-old boy with precocious puberty related to histologically proven Leydig cell tumor. CASE PRESENTATION: Multiparametric ultrasound and magnetic resonance imaging (MRI) was performed. Interesting findings were scarcely or never reported in children and differed from adults Leydig cell tumors s such as the hyperechogenic halo surrounding the lesion and the dominant central vascularization using ultrasensitive Doppler. MRI revealed an enlarged testicle with strong enhancement of a tumor, a tumor apparent diffusion coefficient (ADC) of 600 × 10-3 mm2/s and a lower ADC value of the non-tumor parenchyma compared to the contralateral testis (ADC = 800 × 10-3 mm2/s vs 1100 × 10-3 mm2/s), attributed to the spermatogenesis induced by hormonal impregnation. CONCLUSION: We illustrate multiparametric US and MRI findings of a pediatric Leydig cell tumor, including the imaging changes attributed to local hormone secretion, which may be helpful in similar cases.