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1.
Medicine (Baltimore) ; 97(10): e0093, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29517680

RESUMEN

RATIONALE: The incidence of severe hyperandrogenism associated with masculinity in women is very low. While rare and difficult to diagnose, androgen secreting tumors should be suspected in women with hyperandrogenism and hirsutism, especially in the postmenopausal population. Herein we present one case of ovarian Leydig cell tumor (LCT) with markedly elevated serum testosterone levels and frank hirsutism. PATIENT CONCERNS: A 60-year-old woman, presented with increased hair growth and androgenic alopecia and the hormonal laboratory examination showed that she had elevated serum testosterone level and normal dehydroepiandrosterone sulfate (DHEAS), androstenedione, 17- hydroxyprogesterone, cortisol and thyroid stimulating hormone (TSH). DIAGNOSES: The diagnosis of possible testosterone secreting tumor was performed when pelvic computed tomography (CT) and magnetic resonance image (MRI) showed a right adnexal mass of 15mm×16mm indicative of sex cord- stromal tumors. INTERVENTIONS: The patient received laparoscopic total abdominal hysterectomy and bilateral salpingo-oophorectomy. OUTCOMES: After operation, testosterone got back to the normal level and clinical symptoms subsided. LESSONS: It is common that postmenopausal androgen excess is a state of relative or absolute androgen excess originating from the adrenal gland and/or ovaries. In either case, doctors need to assess such patients and exclude relatively rare potential causes of tumors. Any woman who has hirsutism or frank evidence of markedly increased testosterone should exclude this kind of possibility of androgen producing tumors. It is possible to determine the origin of androgen hypersecretion with the severity of symptoms, the extent of androgen excess, and the relevant imaging studies. Since LCT are rare ovarian sex-cord stromal tumors, it can be beneficial for diagnosis with careful research of patient history of the defeminization followed by virilization, and a CT and MRI image.


Asunto(s)
Hirsutismo/etiología , Hiperandrogenismo/complicaciones , Tumor de Células de Leydig/diagnóstico por imagen , Neoplasias Ováricas/diagnóstico por imagen , Femenino , Humanos , Tumor de Células de Leydig/etiología , Persona de Mediana Edad , Neoplasias Ováricas/etiología , Ovario/diagnóstico por imagen , Posmenopausia , Ultrasonografía
2.
Exp Toxicol Pathol ; 63(7-8): 645-56, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20541379

RESUMEN

Historical data for Leydig cell tumors from untreated or vehicle treated rats from carcinogenicity studies collected in the RITA database are presented. Examples are given for analyses of these data for dependency on variables considered to be of possible influence on the spontaneous incidence of Leydig cell tumors. In the 7453 male rats available for analysis, only one case of a Leydig cell carcinoma was identified. The incidence of Leydig cell adenomas differed markedly between strains. High incidences of close to 100% have been found in F344 rats, while the mean incidence was 4.2% in Sprague-Dawley rats and 13.7% in Wistar rats. Incidences in Wistar rats were highly variable, primarily caused by different sources of animals. Mean incidences per breeder varied from 2.8 to 39.9%. Analyses for the dependency on further parameters have been performed in Wistar rats. In breeders G and I, the Leydig cell tumor incidence decreased over the observation period and with increasing mean terminal body weight. The incidence of Leydig cell tumors increased with mean age at necropsy and was higher in studies with dietary admixture compared to gavage studies. These parameters had no effect on Leydig cell tumor incidence in breeders A and B. Animals from almost all breeders had a considerably higher mean age at necropsy when bearing a Leydig cell adenoma than animals without a Leydig cell adenoma. Studies with longitudinal trimming of the testes had a higher incidence than studies with transverse trimming. The observed dependencies and breeder differences are discussed and explanations are given. Consequences for the use of historical control data are outlined. With the retrospective analyses presented here we were able to confirm the published features of Leydig cell adenomas and carcinomas. This indicates that the RITA database is a valuable tool for analyses of tumors for their biological features. Furthermore, it demonstrates that the RITA database is highly beneficial for the definition of reliable historical control data for carcinogenicity studies on a scientifically solid basis.


Asunto(s)
Adenocarcinoma/etiología , Adenoma/etiología , Pruebas de Carcinogenicidad , Carcinógenos/clasificación , Tumor de Células de Leydig/etiología , Sistema de Registros/estadística & datos numéricos , Adenocarcinoma/epidemiología , Adenoma/epidemiología , Animales , Recolección de Datos , Bases de Datos Factuales/estadística & datos numéricos , Tumor de Células de Leydig/epidemiología , Masculino , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Valores de Referencia
3.
Intern Med ; 48(8): 601-5, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19367056

RESUMEN

A 46-year-old man was admitted in our hospital with hypoglycemia; his FPG was 43 mg/mL. Five years earlier, he underwent simultaneous surgeries for an adrenal adenoma, a benign Leydig cell tumor (LCT), and a malignant lymphoma. Based on the laboratory results, he was diagnosed as congenital adrenal hyperplasia (CAH) due to nonclassical 21-hydroxylase deficiency (21-OHD). On immunohistochemistry analysis using the antibody against adrenal-specific 11beta-hydroxylase antibody, the LCT showed both properties as a testicular cell and as an adrenal cell. The genetic background of 21-OHD might contribute to the development of malignant lymphoma. Such as a case of LCT and malignant lymphoma in a patient with 21-OHD seems to be rare.


Asunto(s)
Hiperplasia Suprarrenal Congénita/complicaciones , Hiperplasia Suprarrenal Congénita/diagnóstico , Tumor de Células de Leydig/etiología , Linfoma/etiología , Neoplasias Testiculares/etiología , Neoplasias de las Glándulas Suprarrenales/etiología , Neoplasias de las Glándulas Suprarrenales/cirugía , Adenoma Corticosuprarrenal/etiología , Adenoma Corticosuprarrenal/cirugía , Humanos , Hipoglucemia/diagnóstico , Hipoglucemia/etiología , Tumor de Células de Leydig/cirugía , Linfoma/cirugía , Masculino , Persona de Mediana Edad , Neoplasias Testiculares/cirugía
6.
Int J Gynecol Pathol ; 25(3): 199-215, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16810055

RESUMEN

In recent years, our knowledge of ovarian sex cord-stromal tumors has increased, and their classification has evolved. In this review, recent advances in the classification and pathology of ovarian sex cord-stromal tumors are discussed, and the controversy regarding the classification of sex cord tumor with annular tubules is addressed. The current classification is built on those of the past, and future classifications should improve on what is now in place incorporating new knowledge from more sophisticated clinicopathologic studies and advanced molecular techniques. This review emphasizes articles written in the 21st century as well as those that have significantly advanced our knowledge of sex cord-stromal tumors in past decades. The tumors in this group occur over a wide age range and are often unilateral. In difficult cases, immunocytochemistry provides improved diagnostic accuracy. The most useful immunohistochemical marker for their identification is alpha-inhibin, which is positive in most neoplasms in the sex cord-stromal group. The article concludes with a section discussing the pathogenesis of sex cord-stromal tumors.


Asunto(s)
Neoplasias Ováricas/clasificación , Neoplasias Ováricas/patología , Tumores de los Cordones Sexuales y Estroma de las Gónadas/clasificación , Tumores de los Cordones Sexuales y Estroma de las Gónadas/patología , Biomarcadores de Tumor/análisis , Femenino , Fibroma/clasificación , Fibroma/etiología , Fibroma/patología , Tumor de Células de la Granulosa/clasificación , Tumor de Células de la Granulosa/etiología , Tumor de Células de la Granulosa/patología , Humanos , Inmunohistoquímica , Inhibinas/análisis , Tumor de Células de Leydig/clasificación , Tumor de Células de Leydig/etiología , Tumor de Células de Leydig/patología , Luteoma/clasificación , Luteoma/etiología , Luteoma/patología , Neoplasias Ováricas/química , Neoplasias Ováricas/etiología , Tumores de los Cordones Sexuales y Estroma de las Gónadas/química , Tumores de los Cordones Sexuales y Estroma de las Gónadas/etiología , Neoplasia Tecoma/clasificación , Neoplasia Tecoma/etiología , Neoplasia Tecoma/patología
7.
Toxicol Pathol ; 32(1): 79-90, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-14713552

RESUMEN

In utero exposure of male rats to the antiandrogen di(n-butyl) phthalate (DBP) leads to decreased anogenital distance (AGD) on postnatal day (PND) 1, increased areolae retention on PND 13, malformations in the male reproductive tract, and histologic testicular lesions including marked seminiferous epithelial degeneration and a low incidence of Leydig cell (LC) adenomas on PND 90. One objective of this study was to determine the incidence and persistence of decreased AGD, increased areolae retention, and LC adenomas in adult rats following in utero DBP exposure. A second objective was to determine whether AGD and areolae retention during the early postnatal period are associated with lesions in the male reproductive tract. Pregnant Crl:CD(SD)BR rats were gavaged with corn oil or DBP at 100 or 500 mg/kg/day, 10 dams per group. Three replicates of rats (n = 30 rats per replicate) were exposed from gestation day 12 to 21 and the male offspring allowed to mature to 6, 12, or 18 months of age. Gross malformations in the male reproductive tract and histologic lesions in the testes were similar to those previously described. However, testicular dysgenesis, a lesion of proliferating LCs and aberrant tubules that has not been previously described in DBP-exposed testes, was diagnosed. The incidence of this lesion was approximately 20% unilateral and 7-18% bilateral in the high-dose group and was similar among all ages examined, implicating a developmental alteration rather than an age-related change. AGD and areolae retention were found to be permanent changes following in utero exposure to 500 mg/kg/day of DBP. Decreased AGD was a sensitive predictor of lesions in the male reproductive tract, relatively small changes in AGD were associated with a significant incidence of male reproductive malformations. In utero DBP exposure induced proliferative developmental lesions, some of which would have been diagnosed as LC adenomas by the morphological criteria set forth by the Society of Toxicologic Pathology. However, these lesions were dissimilar to traditional LC adenomas as the LCs were poorly differentiated and the lesions contained aberrant seminiferous tubules. While the morphology and incidence of this DBP-induced testicular developmental lesion has been fully characterized by this study, the detailed pathogenesis warrants further investigation.


Asunto(s)
Dibutil Ftalato/toxicidad , Genitales Masculinos/efectos de los fármacos , Exposición Materna/efectos adversos , Efectos Tardíos de la Exposición Prenatal , Adenoma/etiología , Adenoma/patología , Animales , Dibutil Ftalato/administración & dosificación , Femenino , Genitales Masculinos/patología , Tumor de Células de Leydig/etiología , Tumor de Células de Leydig/patología , Longevidad/efectos de los fármacos , Masculino , Embarazo , Ratas , Ratas Sprague-Dawley , Maduración Sexual/efectos de los fármacos , Testículo/anomalías , Testículo/efectos de los fármacos , Factores de Tiempo
8.
Rev. chil. urol ; 69(2): 183-184, 2004. ilus
Artículo en Español | LILACS | ID: lil-393974

RESUMEN

Los tumores testiculares se originan, en más del 95 porciento de los casos, de las células germinales. El resto nace de las células del intersticio. En este grupo se encuentra el tumor de células de Leydig, el cual representa el 1 porciento de todos los tumores testiculares. En general, esta neoplasia tiene un comportamiento benigno y su manejo no difiere de los otros tumores. Presentamos este caso clínico debido a su muy baja frecuencia en la práctica clínica.


Asunto(s)
Humanos , Masculino , Adulto , Tumor de Células de Leydig/diagnóstico , Tumor de Células de Leydig/etiología , Tumor de Células de Leydig/prevención & control
9.
Oncogene ; 22(21): 3269-78, 2003 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-12761497

RESUMEN

Transgenic (TG) mice expressing the Simian virus 40 T-antigen under the control of the murine inhibin-alpha promoter (Inhalpha/Tag) develop granulosa and Leydig cell tumors at the age of 5-6 months, with 100% penetrance. When these mice are gonadectomized, they develop adrenocortical tumors. Suppression of gonadotropin secretion inhibits the tumorigenesis in the gonads of intact animals and in the adrenals after gonadectomy. To study further the role of luteinizing hormone (LH) in gonadal and adrenal tumorigenesis, a double TG mouse model was generated by crossing the Inhalpha/Tag mice with mice producing constitutively elevated levels of LH (bLHbeta-CTP mice). Our results show that in double TG mice (bLHbeta-CTP/Inhalpha/Tag), gonadal tumorigenesis starts earlier and progresses faster than in Inhalpha/Tag mice. Both ovarian and testicular tumors were histologically comparable with the tumors found in Inhalpha/Tag mice. In addition, adrenal tumorigenesis was found in intact double TG females, but not in Inhalpha/Tag females. Inhibin-alpha and LH receptor (LHR) were highly expressed in tumorigenic gonadal tissues, and the elevated LH levels were shown to be associated with ectopic LHR and high inhibin-alpha expression in the female adrenals. We conclude that in the Inhalpha/Tag tumor mouse model, elevated LH levels act as a tumor promoter, advancing gonadal and adrenal tumorigenesis.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/etiología , Antígenos Transformadores de Poliomavirus/genética , Inhibinas/genética , Hormona Luteinizante de Subunidad beta/genética , Neoplasias Ováricas/etiología , Neoplasias Testiculares/etiología , Neoplasias de la Corteza Suprarrenal/metabolismo , Neoplasias de la Corteza Suprarrenal/patología , Glándulas Suprarrenales/metabolismo , Animales , Fusión Artificial Génica , Gonadotropina Coriónica Humana de Subunidad beta/genética , Femenino , Tumor de Células de la Granulosa/etiología , Tumor de Células de la Granulosa/metabolismo , Tumor de Células de la Granulosa/patología , Hormonas/sangre , Inhibinas/biosíntesis , Tumor de Células de Leydig/etiología , Tumor de Células de Leydig/metabolismo , Tumor de Células de Leydig/patología , Hormona Luteinizante/biosíntesis , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Transgénicos , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Regiones Promotoras Genéticas , ARN Mensajero/biosíntesis , Receptores de HL/biosíntesis , Receptores de HL/genética , Virus 40 de los Simios/inmunología , Neoplasias Testiculares/metabolismo , Neoplasias Testiculares/patología
10.
Crit Rev Toxicol ; 33(6): 655-780, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14727734

RESUMEN

Widely varied chemicals--including certain herbicides, plasticizers, drugs, and natural products--induce peroxisome proliferation in rodent liver and other tissues. This phenomenon is characterized by increases in the volume density and fatty acid oxidation of these organelles, which contain hydrogen peroxide and fatty acid oxidation systems important in lipid metabolism. Research showing that some peroxisome proliferating chemicals are nongenotoxic animal carcinogens stimulated interest in developing mode of action (MOA) information to understand and explain the human relevance of animal tumors associated with these chemicals. Studies have demonstrated that a nuclear hormone receptor implicated in energy homeostasis, designated peroxisome proliferator-activated receptor alpha (PPARalpha), is an obligatory factor in peroxisome proliferation in rodent hepatocytes. This report provides an in-depth analysis of the state of the science on several topics critical to evaluating the relationship between the MOA for PPARalpha agonists and the human relevance of related animal tumors. Topics include a review of existing tumor bioassay data, data from animal and human sources relating to the MOA for PPARalpha agonists in several different tissues, and case studies on the potential human relevance of the animal MOA data. The summary of existing bioassay data discloses substantial species differences in response to peroxisome proliferators in vivo, with rodents more responsive than primates. Among the rat and mouse strains tested, both males and females develop tumors in response to exposure to a wide range of chemicals including DEHP and other phthalates, chlorinated paraffins, chlorinated solvents such as trichloroethylene and perchloroethylene, and certain pesticides and hypolipidemic pharmaceuticals. MOA data from three different rodent tissues--rat and mouse liver, rat pancreas, and rat testis--lead to several different postulated MOAs, some beginning with PPARalpha activation as a causal first step. For example, studies in rodent liver identified seven "key events," including three "causal events"--activation of PPARalpha, perturbation of cell proliferation and apoptosis, and selective clonal expansion--and a series of associative events involving peroxisome proliferation, hepatocyte oxidative stress, and Kupffer-cell-mediated events. Similar in-depth analysis for rat Leydig-cell tumors (LCTs) posits one MOA that begins with PPARalpha activation in the liver, but two possible pathways, one secondary to liver induction and the other direct inhibition of testicular testosterone biosynthesis. For this tumor, both proposed pathways involve changes in the metabolism and quantity of related hormones and hormone precursors. Key events in the postulated MOA for the third tumor type, pancreatic acinar-cell tumors (PACTs) in rats, also begin with PPARalpha activation in the liver, followed by changes in bile synthesis and composition. Using the new human relevance framework (HRF) (see companion article), case studies involving PPARalpha-related tumors in each of these three tissues produced a range of outcomes, depending partly on the quality and quantity of MOA data available from laboratory animals and related information from human data sources.


Asunto(s)
Carcinógenos/toxicidad , Transformación Celular Neoplásica , Modelos Animales de Enfermedad , Receptores Citoplasmáticos y Nucleares/fisiología , Factores de Transcripción/fisiología , Animales , Bioensayo/métodos , Proteínas de Unión al ADN , Ácidos Grasos/metabolismo , Humanos , Tumor de Células de Leydig/etiología , Tumor de Células de Leydig/fisiopatología , Peroxidación de Lípido , Hígado/efectos de los fármacos , Hígado/fisiología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/fisiopatología , Masculino , Ratones , Microcuerpos , Proteínas Nucleares , Oxidación-Reducción , Páncreas/efectos de los fármacos , Páncreas/patología , Neoplasias Pancreáticas/etiología , Neoplasias Pancreáticas/fisiopatología , Primates , Ratas , Proteínas Represoras , Medición de Riesgo , Neoplasias Testiculares/etiología , Neoplasias Testiculares/fisiopatología , Testículo/efectos de los fármacos , Testículo/patología , Dedos de Zinc
11.
Comp Med ; 50(2): 212-7, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10857013

RESUMEN

BACKGROUND AND PURPOSE: The sexual activity of male tree shrews is socially influenced; therefore, the testicular lesions in adult male tree shrews were of interest. METHODS: The testes of 229 adult and 9 subadult male tree shrews were obtained during routine necropsy and were subjected to light microscopy. At one time, 138 animals were experimentally exposed to social conflicts. RESULTS: Hypospermatogenesis (testicular inactivity) was observed in social stress-exposed males up to two years of age. Seasonality of hypospermatogenesis could not be statistically supported. Testicular atrophy, observed in 21 animals, was neither stress- nor age-related; it developed unilaterally, with the left testis preferred. Testicular tumors developed in animals older than 2 years, with increasing frequency particularly of Leydig cell tumors in animals more than four year old. CONCLUSION: Testicular lesions were more frequently found in male tree shrews than they were observed in nonhuman primates kept at the German Primate Center. Connections to social stress were statistically supported, particularly with respect to hypospermatogenesis. Testicular tumors, in contrast, were distinctly age related.


Asunto(s)
Enfermedades Testiculares/etiología , Enfermedades Testiculares/patología , Neoplasias Testiculares/patología , Testículo/patología , Tupaia , Factores de Edad , Animales , Atrofia/etiología , Atrofia/patología , Dominación-Subordinación , Hamartoma/etiología , Hamartoma/patología , Incidencia , Tumor de Células de Leydig/etiología , Tumor de Células de Leydig/patología , Masculino , Necrosis , Oligospermia/etiología , Oligospermia/patología , Estudios Retrospectivos , Estaciones del Año , Seminoma/etiología , Seminoma/patología , Tumor de Células de Sertoli/etiología , Tumor de Células de Sertoli/patología , Espermatogénesis/fisiología , Estrés Fisiológico/patología , Neoplasias Testiculares/etiología
12.
Am J Pathol ; 156(1): 347-53, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10623684

RESUMEN

Despite recent advances in diagnosis and treatment of testicular cancer, its causes remain unknown. The most common conditions known to be associated with testicular cancer are cryptorchidism, infertility, and overexposure to pesticides or radiation. Recent studies also indicate hormones may play a crucial role in testicular tumorigenesis. Our studies show that about half of the male transgenic mice overexpressing aromatase in testis were infertile and/or had larger than normal testicles. Gross pathology and histological analysis showed the mice to have Leydig cell tumors, unilaterally or bilaterally. Serum estradiol levels for transgenic mice were at least twice as high as those for nontransgenic mice. Expression of aromatase and estrogen receptor were also very high in testicular tissue of transgenic mice compared to nontransgenic mice. Consistent with increased estrogenic activity in the testicular tissue, we also saw an increase in the levels of genes involved in cell cycle that are regulated by the estrogen. To obtain a better understanding of the biological significance of testicular tumorigenesis, a reliable animal model is necessary to clarify the mechanisms and correlations associated with human cancers. Here we describe such a model, which shows that overexpression of aromatase results in increased estrogen production and a changed hormone milieu, leading to the induction of testicular cancer (Leydig cell tumors). This predictable and useful model is a potential tool for the study of testicular tumorigenesis, hormonal carcinogenesis, synergistic action of other carcinogens on hormone-induced tumors, and tumor dependency on endocrine factors.


Asunto(s)
Aromatasa/metabolismo , Tumor de Células de Leydig/etiología , Neoplasias Testiculares/etiología , Animales , Aromatasa/genética , Ciclo Celular/genética , Modelos Animales de Enfermedad , Estradiol/sangre , Receptor alfa de Estrógeno , Tumor de Células de Leydig/patología , Células Intersticiales del Testículo/enzimología , Masculino , Ratones , Ratones Transgénicos/genética , Receptores de Estrógenos/metabolismo , Neoplasias Testiculares/patología , Testículo/enzimología , Regulación hacia Arriba
13.
Crit Rev Toxicol ; 29(2): 169-261, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10213111

RESUMEN

Leydig cells (LCs) are the cells of the testis that have as their primary function the production of testosterone. LCs are a common target of compounds tested in rodent carcinogenicity bioassays. The number of reviews on Leydig cell tumors (LCTs) has increased in recent years because of its common occurrence in rodent bioassays and the importance in assessing the relevance of this tumor type to humans. To date, there have been no comprehensive reviews to identify all the compounds that have been shown to induce LCTs in rodents or has any review systematically evaluated the epidemiology data to determine whether humans were at increased risk for developing LCTs from exposure to these agents. This review attempts to fill these deficiencies in the literature by comparing the cytology and ontogeny of the LC, as well as the endocrine and paracrine regulation of both normal and tumorigenic LCs. In addition, the pathology of LCTs in rodents and humans is compared, compounds that induce LC hyperplasia or tumors are enumerated, and the human relevance of chemical-induced LCTs is discussed. There are plausible mechanisms for the chemical induction of LCTs, as typified by agonists of estrogen, gonadotropin releasing hormone (GnRH), and dopamine receptors, androgen receptor antagonists, and inhibitors of 5alpha-reductase, testosterone biosynthesis, and aromatase. Most of these ultimately involve elevation in serum luteinizing hormone (LH) and/or LC responsiveness to LH as proximate mediators. It is expected that further work will uncover additional mechanisms by which LCTs may arise, especially the role of growth factors in modulating LC tumorigenesis. Regarding human relevance, the pathways for regulation of the hypothalamo-pituitary-testis (HPT) axis of rats and humans are similar, such that compounds that either decrease testosterone or estradiol levels or their recognition will increase LH levels. Hence, compounds that induce LCTs in rats by disruption of the HPT axis pose a risk to human health, except for possibly two classes of compounds (GnRH and dopamine agonists). Because GnRH and prolactin receptors are either not expressed or are expressed at very low levels in the testes in humans, the induction of LCTs in rats by GnRH and dopamine agonists would appear not to be relevant to humans; however, the potential relevance to humans of the remaining five pathways of LCT induction cannot be ruled out. Therefore, the central issue becomes what is the relative sensitivity between rat and human LCs in their response to increased LH levels; specifically, is the proliferative stimulus initiated by increased levels of LH attenuated, similar, or enhanced in human vs. rat LCs? There are several lines of evidence that suggest that human LCs are quantitatively less sensitive than rats in their proliferative response to LH, and hence in their sensitivity to chemically induced LCTs. This evidence includes the following: (1) the human incidence of LCTs is much lower than in rodents even when corrected for detection bias; (2) several comparative differences exist between rat and human LCs that may contribute, at least in part, to the greater susceptibility of the rat to both spontaneous and xenobiotic-induced LCTs; (3) endocrine disease states in man (such as androgen-insensitivity syndrome and familial male precocious puberty) underscore the marked comparative differences that exist between rats and man in the responsiveness of their LC's to proliferative stimuli; and (4) several human epidemiology studies are available on a number of compounds that induce LCTs in rats (1,3-butadiene, cadmium, ethanol, lactose, lead, nicotine) that demonstrate no association between human exposure to these compounds and induction of LC hyperplasia or adenomas. (ABSTRACT TRUNCATED)


Asunto(s)
Transformación Celular Neoplásica , Modelos Animales de Enfermedad , Tumor de Células de Leydig/etiología , Neoplasias Testiculares/etiología , Xenobióticos/efectos adversos , Animales , Sistema Endocrino/efectos de los fármacos , Humanos , Tumor de Células de Leydig/fisiopatología , Células Intersticiales del Testículo/citología , Células Intersticiales del Testículo/efectos de los fármacos , Hormona Luteinizante/farmacología , Masculino , Pruebas de Mutagenicidad , Ratas , Neoplasias Testiculares/fisiopatología
14.
Wiad Lek ; 50(4-6): 128-31, 1997.
Artículo en Polaco | MEDLINE | ID: mdl-9381716

RESUMEN

Leydig cell tumours deriving from the gonadal stroma represent one per cent of all testicular tumours. They may occur at any age. Ten per cent of cases are malignant. There is no evidence that they are prone to develop in undescended testis. We report the rare case of leydigioma in 71 year old man with unilateral cryptorchidism. Only a few cases have been reported as arising from undescended testis.


Asunto(s)
Criptorquidismo/complicaciones , Tumor de Células de Leydig/etiología , Neoplasias Testiculares/etiología , Anciano , Humanos , Tumor de Células de Leydig/patología , Masculino , Neoplasias Testiculares/patología
15.
Mol Cell Endocrinol ; 119(2): 135-46, 1996 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-8807633

RESUMEN

Testicular tumorigenesis was observed in transgenic mice expressing the 6-kb mouse inhibin alpha-subunit promoter/Simian virus 40 T-antigen (SV40 Tag) fusion gene. The tumors were confined to Leydig cells using immunohistochemistry with anti-Tag antibody, specific binding of biotinylated hCG and histochemistry for 3 beta-hydroxysteroid dehydrogenase. Leydig cell hyperplasia and presence of Tag protein in the testicular interstitial tissue were already evident at 5 and 6.5 days of age, respectively. An immortalized cell line, BLT-1, was established from one testicular tumor. These cells expressed the LH receptor and P450scc mRNAs, and displayed LH-responsive cAMP and progesterone production, and low testosterone production. The cells also specifically bound 125I-labeled recombinant human LH with high affinity (36000 binding sites/cell), and the binding was regulated by 8Br-cAMP and hCG. This gonadal tumor model is valuable for further studies on endocrine functions of Leydig cells and their tumorigenesis in vivo and in vitro.


Asunto(s)
Antígenos Transformadores de Poliomavirus/genética , Inhibinas , Tumor de Células de Leydig/etiología , Péptidos/genética , Regiones Promotoras Genéticas/genética , Virus 40 de los Simios/inmunología , 3-Hidroxiesteroide Deshidrogenasas/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/farmacología , Animales , Antígenos Transformadores de Poliomavirus/fisiología , Línea Celular Transformada , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/genética , Gonadotropina Coriónica/metabolismo , Gonadotropina Coriónica/farmacología , AMP Cíclico/análisis , Humanos , Hiperplasia , Tumor de Células de Leydig/patología , Tumor de Células de Leydig/fisiopatología , Células Intersticiales del Testículo/patología , Hormona Luteinizante/metabolismo , Masculino , Ratones , Ratones Transgénicos , Progesterona/análisis , ARN Mensajero/análisis , Receptores de HL/análisis , Receptores de HL/genética , Neoplasias Testiculares/etiología , Neoplasias Testiculares/patología , Testosterona/análisis
16.
J Gerontol A Biol Sci Med Sci ; 50(2): B72-7, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7874582

RESUMEN

The effects of dietary restriction (DR) on spontaneous oncogenesis in male Fischer 344 rats were analyzed. Previously reported analyses of studies carried out in our laboratory demonstrated that DR reduces the incidence and delays the onset, but not the progression, of leukemia in male F344 rats. In this report, the influence of DR on pituitary tumors, adrenal pheochromocytoma, pancreatic islet cell tumors, and interstitial cell tumors of the testis was analyzed. DR reduced the relative incidence (relative onset rates) and delayed the onset of the four tumors. DR also retarded the progression (duration from onset to death) of pituitary tumors and pheochromocytoma. DR has delayed the onset of all tumors of the male F344 rat so far analyzed, but its effect on tumor progression appears to be lesion-dependent.


Asunto(s)
Dieta , Ingestión de Energía/fisiología , Neoplasias Experimentales/etiología , Adenoma de Células de los Islotes Pancreáticos/etiología , Adenoma de Células de los Islotes Pancreáticos/fisiopatología , Neoplasias de las Glándulas Suprarrenales/etiología , Neoplasias de las Glándulas Suprarrenales/fisiopatología , Edad de Inicio , Animales , Progresión de la Enfermedad , Tumor de Células de Leydig/etiología , Tumor de Células de Leydig/fisiopatología , Masculino , Neoplasias Experimentales/fisiopatología , Neoplasias Pancreáticas/etiología , Neoplasias Pancreáticas/fisiopatología , Feocromocitoma/etiología , Feocromocitoma/fisiopatología , Neoplasias Hipofisarias/etiología , Neoplasias Hipofisarias/fisiopatología , Ratas , Ratas Endogámicas F344 , Tasa de Supervivencia , Neoplasias Testiculares/etiología , Neoplasias Testiculares/fisiopatología
17.
Am J Med Sci ; 309(1): 63-5, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7825657

RESUMEN

Leydig cell tumors are very rarely seen testicular tumors and can be difficult to distinguish from testicular tumors of the adrenogenital syndrome. Testicular tumors of the adrenogenital syndrome are confined to patients with congenital adrenal hyperplasia. The authors report a case of a patient with malignant Leydig cell tumor and a history of congenital adrenal hyperplasia (adrenogenital syndrome). To the authors' knowledge, this has not been reported previously.


Asunto(s)
Hiperplasia Suprarrenal Congénita/complicaciones , Tumor de Células de Leydig/etiología , Neoplasias Testiculares/etiología , Hiperplasia Suprarrenal Congénita/cirugía , Adulto , Humanos , Tumor de Células de Leydig/patología , Masculino , Orquiectomía , Neoplasias Testiculares/patología
19.
Cancer ; 72(4): 1305-7, 1993 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-8393373

RESUMEN

BACKGROUND: Testicular germ cell neoplasms occur bilaterally in approximately 2-5% of patients. Bilateral testicular tumors of different histogenesis are extremely rare, and the study of such cases may offer clues to the pathogenesis of both tumor entities. METHODS: A report of a case and review of the literature are presented. RESULTS: A 33-year-old man had a right-sided testicular neoplasm consisting of teratoma, embryonal carcinoma, and yolk sac tumor. Retroperitoneal lymph node metastases were excised, and, subsequently, adjuvant abdominal radiation therapy was administered. The patient later received six cycles of cisplatin-based chemotherapy for pulmonary relapse. When he was 40 years of age, a contralateral Leydig cell tumor (LCT) was treated by testis-sparing excision. This is the first observation of testicular germ cell tumor (GCT) and contralateral LCT. Three cases of germ cell neoplasm and concurrent ipsilateral LCT have been reported previously. CONCLUSIONS: The association of GCT and LCT in one patient is quite unusual because both entities are rare. Sharing of common etiologic factors by both entities is a possible explanation.


Asunto(s)
Tumor de Células de Leydig/patología , Neoplasias de Células Germinales y Embrionarias/patología , Neoplasias Primarias Múltiples/patología , Neoplasias Testiculares/patología , Adulto , Hormona Folículo Estimulante/sangre , Humanos , Tumor de Células de Leydig/sangre , Tumor de Células de Leydig/etiología , Tumor de Células de Leydig/secundario , Tumor de Células de Leydig/terapia , Neoplasias Pulmonares/secundario , Escisión del Ganglio Linfático , Metástasis Linfática , Masculino , Neoplasias de Células Germinales y Embrionarias/sangre , Neoplasias de Células Germinales y Embrionarias/etiología , Neoplasias de Células Germinales y Embrionarias/secundario , Neoplasias de Células Germinales y Embrionarias/terapia , Neoplasias Primarias Múltiples/sangre , Neoplasias Primarias Múltiples/etiología , Neoplasias Primarias Múltiples/terapia , Neoplasias Testiculares/sangre , Neoplasias Testiculares/etiología , Neoplasias Testiculares/terapia
20.
J Pediatr Surg ; 27(5): 639-41, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1320675

RESUMEN

The association between testicular tumors/nodules and congenital adrenal hyperplasia (CAH) has been previously reported. From 1960 to 1989, three patients (13 to 18 years old) with long-standing CAH developed testicular masses. Two patients with 21-hydroxylase deficiency were diagnosed in the neonatal period while one other with 11-hydroxylase deficiency was diagnosed at 3 years of age when he presented with sexual precocity. In all three patients, medical compliance was poor. The testicular masses were bilateral in two patients and unilateral in one, measured 1 to 2 cm, and occupied only the upper half of the testicle. Testicular biopsy specimens were obtained after at least 6 months of evidence of compliance with the adrenocorticotrophic hormone (ACTH) suppressive medication and failure of the nodules to regress. On gross examination the masses appeared to be firm yellow brown nodules. Light microscopy showed interlacing strands, cords, and rests of cells resembling interstitial (Leydig) cells but with no Reinke crystalloids. Electronmicroscopy in all patients showed variable amounts of both smooth and rough endoplasmic reticulum, the later with occasional dilated cisternae. Follow-up ranged from 6 months to 6 years. No further surgical treatment has been necessary. There has been no evidence of recurrence, distant metastases, or secondary malignancies during the time of follow-up. These findings suggest that testicular tumors may develop from chronic excessive ACTH stimulation of a putative pluripotential testicular cell, a Leydig cell, or an adrenal cortical rest. Unlike other testicular tumors these do not require orchiectomy as the initial form of therapy.


Asunto(s)
Hiperplasia Suprarrenal Congénita , Hiperplasia Suprarrenal Congénita/complicaciones , Hormona Adrenocorticotrópica/administración & dosificación , Tumor de Células de Leydig/etiología , Células Intersticiales del Testículo/patología , Neoplasias Testiculares/etiología , Testículo/patología , Adolescente , Hiperplasia Suprarrenal Congénita/tratamiento farmacológico , Hiperplasia Suprarrenal Congénita/enzimología , Humanos , Lactante , Recién Nacido , Tumor de Células de Leydig/patología , Tumor de Células de Leydig/cirugía , Tumor de Células de Leydig/ultraestructura , Células Intersticiales del Testículo/ultraestructura , Masculino , Microscopía Electrónica , Estadificación de Neoplasias , Orquiectomía , Cooperación del Paciente , Neoplasias Testiculares/patología , Neoplasias Testiculares/cirugía , Neoplasias Testiculares/ultraestructura , Testículo/ultraestructura
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