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1.
Prev Vet Med ; 185: 105201, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33229065

RESUMO

Canine testicular tumors account for about 90 % of tumors affecting the male genitalia. Seminomas (SEM), Sertoli cell tumors (SCT), and interstitial cell tumors (ICT) are the most common histological diagnoses, but their incidence shows high variability among studies. Our aim is to report the results on the analysis of testicular tumors recorded by the population-based Umbria Canine Cancer Registry (CCR) for a 5-year time period and to assess the value of tumor major diameter, measured during trimming, in discriminating neoplastic from non-neoplastic lesions. The study was conducted on 388 testicular tumors (on 1969 total male tumors) diagnosed in 355 dogs from 2014 to 2018. The median incidence was 35 cases/100,000 dogs, with a proportion equal to 19,7 % of all tumors. The incidence on neutered male dogs was 352/100,000. Most tumors were ICTs (50 %), with fewer SEMs and SCTs (29 % and 17 %, respectively). Only 3 % of tumors were mixed germ cell-sex cord-stromal tumors (MGC-SCST). Ten percent of cases had multiple tumors in the same testicle, with SEM-ICT being prevalent (69.2 %). Tumors in cryptorchid testes were 5.9 % of the total, mostly SCT (60.9 %). Mean age at diagnosis was 10.7 ± 2.7, with similar values for different tumor types. Significant incidence ratios (IRR) were found in Golden retriever (IRR 7.18, CI95 % 4.72-10.92) and in English cocker spaniel (IRR 2.30, CI95 % 1.28-4.13) when compared with mixed breed dogs. A value of 0.3 cm (major diameter) of lesions at the moment of trimming was helpful in discriminating a final tumor histological diagnosis from a non-tumor lesion. Since the number of tumors included in this evaluation was limited, further studies to confirm the diagnostic value of this measure are recommended. Our results provided information on the incidence of canine testicular tumors in Umbria region that can be compared with future results and incidence from other geographical areas if provided with reliable data on the total population, can offer solid information on the incidence and proportion of different tumor types in specific territories, contributing also to the supervision of its inhabitants' health. Moreover, pathological data such as the major diameter of tumors can be obtained and contribute to diagnostic routine and standardization.


Assuntos
Doenças do Cão/epidemiologia , Tumor de Células de Leydig/veterinária , Seminoma/veterinária , Tumor de Células de Sertoli/veterinária , Neoplasias Testiculares/veterinária , Animais , Estudos de Coortes , Cães , Incidência , Itália/epidemiologia , Tumor de Células de Leydig/epidemiologia , Masculino , Sistema de Registros , Seminoma/epidemiologia , Tumor de Células de Sertoli/epidemiologia , Neoplasias Testiculares/epidemiologia
2.
J Urol ; 203(5): 949-956, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31845841

RESUMO

PURPOSE: Leydig cell tumors are rare but they are the most common nongerm cell testicular tumors. Only limited evidence exists for reliably differentiating between benign and malignant Leydig cell tumors and for optimally managing the different types and stages of this rare disease. In this review we synthesize the available evidence on the clinical presentation and clinicopathological characteristics associated with Leydig cell tumor malignancy and management. MATERIALS AND METHODS: We analyzed published case series data on Leydig cell tumors. The association between clinicopathological variables and the presence of metastatic disease was assessed using regression analyses. RESULTS: We included 357 reports, reviewing available data from 1,375 patients (median age 34 years). Testis sparing surgery was performed in 463 patients. Local recurrence after testis sparing surgery occurred in 8 of 121 (7%) patients with available followup information. Metastases were found in 101 patients and were most often located in the retroperitoneal lymph nodes (60%), lungs (38%) and/or liver (29%). The multivariable models with or without multiple imputation predicting metastatic disease included older age, larger tumor size, presence of any adverse factor (larger tumor diameter, necrosis, angiolymphatic invasion, pleomorphism, high mitotic index, atypia) and any protective factor (Reinke crystals, lipofuscin pigments, gynecomastia) with model AUCs of 0.93. Durable remission after resection of metastases or use of platinum based chemotherapy was rarely seen. CONCLUSIONS: Our risk tables using clinicopathological parameters can help identify patients with malignant tumors. These patients should undergo disease staging and be followed or receive further treatment. In some patients with metastatic disease surgical and systemic treatment might result in disease control.


Assuntos
Tumor de Células de Leydig/terapia , Neoplasias Testiculares/terapia , Terapia Combinada , Saúde Global , Humanos , Tumor de Células de Leydig/diagnóstico , Tumor de Células de Leydig/epidemiologia , Masculino , Morbidade/tendências , Fatores de Risco , Taxa de Sobrevida/tendências , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/epidemiologia , Resultado do Tratamento
3.
Asian Pac J Cancer Prev ; 16(8): 3443-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25921159

RESUMO

BACKGROUND: Testicular tumors constitute a rare type of cancer affecting adolescents and young adults with recent reports confirming an increase in incidence worldwide. The purpose of this study was to estimate the epidemiological characteristics and histological subtypes of testicular tumors in the Lebanese population according to the WHO classification of testicular and paratesticular tumors. MATERIALS AND METHODS: In this single institutional retrospective study, all patients diagnosed with a testicular tumor in Hotel-Dieu de France Hospital University in Beirut between 1992 and 2014 were enrolled. The age, subtype based on the 2004 WHO classification and body side of tumor were analyzed. RESULTS: A total of two hundred and forty-four (244) patients diagnosed with a testicular tumor in our institution were included in the study. Two hundred and one patients (82.4% of all testicular tumors) had germ cell tumors (TGCT). Among TGCT, 50% were seminomatous tumors, 48% non-seminomatous tumors (NST) and 2% were spermatocytic seminomas. The NST were further divided into mixed germ cell tumors (63.9%), embryonic carcinomas (18.6%), teratomas (15.4%) and yolk sac tumors (2.1%). The mean age for testicular tumors was 32 years. The mean age for germ cell tumors was 31 years and further subtypes such as seminomatous tumors had a mean age of 34 years, 28 years in non-seminomatous tumors and 56 years in spermatocytic seminoma. Patients with right testicular tumor were the predominant group with 55% of patients. Three patients (1.2%) presented with bilateral tumors. CONCLUSIONS: The distribution of different subgroups and the mean age for testicular tumors proved comparable to most countries of the world except for some Asian countries. Germ cell tumors are the most common subtype of testicular tumors with seminomatous tumors being slightly more prevalent than non-seminomatous tumors in Lebanese patients.


Assuntos
Carcinoma Embrionário/epidemiologia , Tumor do Seio Endodérmico/epidemiologia , Tumor de Células de Leydig/epidemiologia , Seminoma/epidemiologia , Teratoma/epidemiologia , Neoplasias Testiculares/epidemiologia , Adulto , Distribuição por Idade , Idoso , Pré-Escolar , Estudos de Coortes , Humanos , Líbano/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/epidemiologia , Estudos Retrospectivos , Tumores do Estroma Gonadal e dos Cordões Sexuais/epidemiologia , Adulto Jovem
4.
Anticancer Drugs ; 24(3): 228-36, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23059385

RESUMO

Neoplasms in the testis and in the testicular adnexa of elderly patients are completely different from those observed in younger patients. Indeed, although conventional seminomas and nonseminomas are mainly observed in the age range of 20-45 years, spermatocytic seminoma, malignant Leydig tumors, and lymphomas in the testis and sarcomas in the paratesticular region are encountered in individuals older than 60 years of age. Here, we discuss the testis and paratesticular region neoplasm more commonly diagnosed in elderly men.


Assuntos
Neoplasias Testiculares/epidemiologia , Neoplasias Testiculares/patologia , Neoplasias Testiculares/terapia , Idoso , Idoso de 80 Anos ou mais , Humanos , Leiomiossarcoma/epidemiologia , Leiomiossarcoma/patologia , Leiomiossarcoma/terapia , Tumor de Células de Leydig/epidemiologia , Tumor de Células de Leydig/patologia , Tumor de Células de Leydig/terapia , Linfoma/epidemiologia , Linfoma/patologia , Linfoma/terapia , Masculino , Prognóstico , Sarcoma/epidemiologia , Sarcoma/patologia , Sarcoma/terapia , Seminoma/epidemiologia , Seminoma/patologia , Neoplasias Testiculares/diagnóstico , Testículo/patologia
5.
J Pediatr Surg ; 47(8): 1576-80, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22901920

RESUMO

OBJECTIVE: Prepubertal testicular tumors are rare and fundamentally distinct from adult testicular tumors. We reviewed our 11-year experience in a single medical center of China. MATERIAL AND METHODS: This study reports the clinical characteristics, histopathologic diagnosis, treatment methods, and outcome in a series of 63 prepubertal boys who were treated between 1997 and 2008. RESULTS: A total of 63 primary prepubertal testicular and paratesticular tumors were identified. The median age at presentation was 11 months. Of these tumors, 27 (42.9%) were mature teratomas, 5 (7.9%) were immature teratomas, 21 (33.3%) were yolk sac tumors, 4 (6.3%) were epidermoid cyst, 2 (3.2%) were Leydig cell tumors, 1 (1.6%) was a mixed malignant germ cell tumor, and 3 (4.8%) were paratesticular tumors. The most common clinical presentation (95.2%) was a painless scrotal mass or swelling. Forty-eight tumors were treated with radical inguinal orchiectomy, and 15, with a testis-sparing procedure. Follow-up was available in 59 cases, range from 4 to 128 months (median, 50 months). One patient with yolk sac tumor had recurrence and progression to metastasis at the end of 4 months after surgery. Other patients were disease free at last follow-up. CONCLUSIONS: Most of the prepubertal testicular lesions were benign, and the most common histologic subtype was teratoma. Our experience with testis-sparing procedures supports the current trends that less invasive treatment should be performed for benign lesions. This study confirms the excellent cure rates obtained in children with prepubertal testicular tumors.


Assuntos
Orquiectomia/métodos , Neoplasias Testiculares/epidemiologia , Idade de Início , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais , Criança , Pré-Escolar , China/epidemiologia , Terapia Combinada , Tumor do Seio Endodérmico/sangue , Tumor do Seio Endodérmico/tratamento farmacológico , Tumor do Seio Endodérmico/epidemiologia , Tumor do Seio Endodérmico/cirurgia , Cisto Epidérmico/epidemiologia , Cisto Epidérmico/cirurgia , Neoplasias dos Genitais Masculinos/diagnóstico por imagem , Neoplasias dos Genitais Masculinos/epidemiologia , Neoplasias dos Genitais Masculinos/cirurgia , Humanos , Incidência , Lactente , Tumor de Células de Leydig/epidemiologia , Tumor de Células de Leydig/cirurgia , Masculino , Neoplasias Embrionárias de Células Germinativas/epidemiologia , Neoplasias Embrionárias de Células Germinativas/cirurgia , Tratamentos com Preservação do Órgão , Estudos Retrospectivos , Teratoma/sangue , Teratoma/diagnóstico por imagem , Teratoma/epidemiologia , Teratoma/cirurgia , Neoplasias Testiculares/sangue , Neoplasias Testiculares/diagnóstico por imagem , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/cirurgia , Resultado do Tratamento , Ultrassonografia , alfa-Fetoproteínas/análise
6.
BJU Int ; 108(10): 1603-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21631694

RESUMO

OBJECTIVE: To report an observed high frequency of Leydig cell tumours (LCTs) diagnosed at our centre. PATIENTS AND METHODS: Charts of all patients who underwent surgery for a testicular tumour between 1999 and 2008 at our department were searched and data from patients with LCT were collected. Before surgery all patients underwent ultrasound and complete staging. In all but two patients with LCT an organ-sparing surgery was performed. Surgery was performed under ultrasound or palpation guidance. All patients underwent postoperative follow-up. We retrospectively reviewed surgical technique, histology, epidemiology and outcome in all LCT patients. RESULTS: In the study period, 197 testicular tumours were surgically removed of which 29 were diagnosed as LCT (14.7% of 197; further study group) in 25 patients. Mean age of patients with LCT was 45 years (range 21-68 years). Tumour size ranged from 1.2 to 80 mm (mean 10.23 mm). In two patients (8%) the lesion was palpable whereas incidental diagnosis was made in seven patients (28%). In the remaining patients diagnosis was made by ultrasound performed for testicular pain (six patients, 24%) or during infertility or erectile dysfunction evaluation (10 patients, 40%). Definitive histology reported no malignant histopathological features in all but one patient; this particular patient experienced tumour progression after 2 months and died from advanced disease 1 year later. All other patients are free of disease after a mean follow up of 56 months (range 7-93 months). During this period one patient developed a second LCT on the contralateral side; another patient had a recurrence within the same testicle, but on the opposite pole. Both underwent a subsequent organ-sparing tumour resection. CONCLUSION: The percentage of LCT (14.7% of all testicular tumours removed) was significantly higher than expected from the literature. One possible explanation for this phenomenon is the increasing use of better ultrasound technology and the subsequent increased detection of small nodules that have not been found in historical series. Use of 'observation-only' for very small lesions detected at infertility clinics is under debate.


Assuntos
Tumor de Células de Leydig/diagnóstico por imagem , Neoplasias Testiculares/diagnóstico por imagem , Adulto , Idoso , Gonadotropina Coriônica Humana Subunidade beta/metabolismo , Humanos , Incidência , L-Lactato Desidrogenase/metabolismo , Tumor de Células de Leydig/epidemiologia , Tumor de Células de Leydig/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Tratamentos com Preservação do Órgão/métodos , Estudos Retrospectivos , Neoplasias Testiculares/epidemiologia , Neoplasias Testiculares/cirurgia , Carga Tumoral , Ultrassonografia , Adulto Jovem , alfa-Fetoproteínas/metabolismo
7.
Vet Comp Oncol ; 9(1): 45-54, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21303453

RESUMO

Histologically verified tumours submitted to the Norwegian Canine Cancer Register from 1990 to 1998 were studied (n=14,401). The proportion of testicular tumours (n=345) was 2.4%, and the breakdown of histological tumour diagnoses is presented. The frequency of the most common histopathological types was 33% interstitial (Leydig), 26.4% Sertoli and 33.9% seminomas/germ cell tumours. The average age at diagnosis was 10 years, but was significantly lower for Sertoli cell tumours (8.6 years) than for the other tumour types. Following a histopathological re-evaluation, 22.5% of the original tumor diagnoses were modified. Proportional morbidity ratios were calculated and individuals from the breeds Shetland sheepdog and Collie were five times more likely to have testicular tumours than the overall average for the registry. Breed differences in the distribution of histopathologic types were observed. Shetland sheepdog and Collie were most commonly diagnosed with Sertoli cell tumours, while all tumours from Norwegian elkhound in this material were seminomas.


Assuntos
Doenças do Cão/epidemiologia , Doenças do Cão/patologia , Tumor de Células de Leydig/veterinária , Sistema de Registros , Seminoma/veterinária , Tumor de Células de Sertoli/veterinária , Fatores Etários , Animais , Doenças do Cão/diagnóstico , Cães , Tumor de Células de Leydig/diagnóstico , Tumor de Células de Leydig/epidemiologia , Tumor de Células de Leydig/patologia , Masculino , Noruega/epidemiologia , Linhagem , Seminoma/diagnóstico , Seminoma/epidemiologia , Seminoma/patologia , Tumor de Células de Sertoli/diagnóstico , Tumor de Células de Sertoli/epidemiologia , Tumor de Células de Sertoli/patologia , Especificidade da Espécie
8.
Exp Toxicol Pathol ; 63(7-8): 645-56, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20541379

RESUMO

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.


Assuntos
Adenocarcinoma/etiologia , Adenoma/etiologia , Testes de Carcinogenicidade , Carcinógenos/classificação , Tumor de Células de Leydig/etiologia , Sistema de Registros/estatística & dados numéricos , Adenocarcinoma/epidemiologia , Adenoma/epidemiologia , Animais , Coleta de Dados , Bases de Dados Factuais/estatística & dados numéricos , Tumor de Células de Leydig/epidemiologia , Masculino , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Valores de Referência
10.
J Pediatr Urol ; 4(2): 134-7, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18631909

RESUMO

OBJECTIVE: To analyze the spectrum of testicular tumors in children in an unselected population-based series, as well as the results of testis-preserving surgery. PATIENTS AND METHODS: Our hospital database was analyzed for operations for testicular tumors from 1981 to 2006. The clinical data and findings during follow up (4.7 years) were recorded. RESULTS: Thirty-four patients were operated on because of testicular tumors. In 23 (68%) the tumor was benign: benign teratoma (16), Leydig-cell tumor (2), epidermoid cyst (2), Sertoli-cell tumor (1), cystic dysplasia (1), intratesticular focal fibrosis (1). Eleven patients (32%) had a malignant tumor: yolk-sac tumor (6), embryonal carcinoma (5). Twenty out of the 26 (77%) prepubertal boys had a benign tumor in contrast to only three of the eight (38%) adolescent males (P=0.079). Testis-preserving surgery was performed in 10 patients. In eight, the tumor was curatively excised and remaining testis preserved. Two patients with benign teratoma had a recurrence due to incomplete primary resection. In one patient who underwent orchiectomy for benign teratoma, two metachronous teratomas were detected in the contralateral testis 6 years after primary surgery. CONCLUSIONS: In children, most testicular tumors are benign, especially before puberty. If testis-preserving surgery is contemplated, complete excision of the tumor should be ascertained. The possibility of metachronous bilateral tumors should be considered in the follow up of testicular teratomas.


Assuntos
Teratoma/epidemiologia , Teratoma/cirurgia , Neoplasias Testiculares/epidemiologia , Neoplasias Testiculares/cirurgia , Adolescente , Carcinoma Embrionário/epidemiologia , Carcinoma Embrionário/cirurgia , Criança , Bases de Dados Factuais , Tumor do Seio Endodérmico/epidemiologia , Tumor do Seio Endodérmico/cirurgia , Cisto Epidérmico/epidemiologia , Cisto Epidérmico/cirurgia , Seguimentos , Humanos , Incidência , Tumor de Células de Leydig/epidemiologia , Tumor de Células de Leydig/cirurgia , Masculino , Estudos Retrospectivos , Tumor de Células de Sertoli/epidemiologia , Tumor de Células de Sertoli/cirurgia
12.
Regul Toxicol Pharmacol ; 50(3): 273-84, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18241965

RESUMO

An increased Leydig cell tumor (LCT) incidence has been reported in a study of Sprague-Dawley (SD) rats exposed via gavage to 1000 (but not 250)mg/kgday MTBE; it is unclear, however, if this finding was indeed dose-related or due to the statistical analyses not having adequately accounted for the increased survival rate in the high-dose animals and/or for multiple statistical comparisons. To address this question, we conducted Hoel-Walburg and Poly-3 analyses, using p-values of 0.01 for pair-wise comparisons and 0.005 for trend tests of common tumors. We found that MTBE does not cause a statistically significant increase in LCTs in SD rats when survival is appropriately taken into account. In addition, the original study reported some overall survival data, but did not specify which rats had LCTs. This led us to conduct separate Poly-3 analyses for the most extreme scenarios of survival age and tumor incidence to provide an illustrative example of approaches for analyzing the impact of survival rates on tumor findings in the absence of animal-specific survival data. We found this method to provide results similar to analyses using the actual data, suggesting that it can be used when full survival data are not available.


Assuntos
Tumor de Células de Leydig/induzido quimicamente , Tumor de Células de Leydig/epidemiologia , Éteres Metílicos/toxicidade , Modelos Estatísticos , Análise de Sobrevida , Neoplasias Testiculares/induzido quimicamente , Neoplasias Testiculares/epidemiologia , Animais , Interpretação Estatística de Dados , Masculino , Ratos , Ratos Sprague-Dawley
13.
J Comp Pathol ; 138(2-3): 86-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18295787

RESUMO

The aim of this study was to provide an up-to-date estimate of the prevalence of canine testicular tumours, an earlier study (reported in 1962) having found a prevalence of 16%. Histological examination of both testes collected at necropsy from 232 dogs revealed that 62 (27%) had one or more testicular tumours, the total number of tumours identified being 110. Of these, 55 were interstitial cell tumours, 46 were seminomas, and nine were Sertoli cell tumours. The results suggest that, as reported in man, testicular tumours in dogs have increased during the past 40 years. Further studies should investigate the possible causative role of environmental pollutants.


Assuntos
Doenças do Cão/patologia , Tumor de Células de Leydig/veterinária , Seminoma/veterinária , Tumor de Células de Sertoli/veterinária , Neoplasias Testiculares/veterinária , Animais , Doenças do Cão/epidemiologia , Cães , Tumor de Células de Leydig/epidemiologia , Tumor de Células de Leydig/patologia , Células Intersticiais do Testículo/patologia , Masculino , Prevalência , Seminoma/epidemiologia , Seminoma/patologia , Tumor de Células de Sertoli/epidemiologia , Tumor de Células de Sertoli/patologia , Neoplasias Testiculares/epidemiologia , Neoplasias Testiculares/patologia
15.
Cancer Lett ; 182(2): 213-6, 2002 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-12048167

RESUMO

Dunning began inbreeding, what is now the Fischer F344 rat, in 1931. Because of her publications showing a low incidence of spontaneous tumors to 35 months of age, we selected the F344 rat for most of the studies in the National Cancer Institute (NCI) Bioassay Program, beginning in 1964. We were surprised by the finding that untreated male F344 rats displayed a high incidence of Leydig cell tumors of the testes beginning at about 17 months of age. The key difference between the results of Dunning and the NCI Bioassay Program was that her animals were retired breeders, whereas the NCI studies utilized virgin rats. The question of breeding was, therefore, examined as a possible protective factor. Groups of male F344 CDF/Crl rats were kept as virgin animals, or permitted access to bilaterally tube ligated female F344/Crl rats that were replaced twice over a 52-week period. At that time, all males from both groups were housed three per cage to 85 weeks when they were killed in a CO(2) atmosphere and necropsied. Sections were prepared from the fixed tissues, stained and studied by histopathology. The results were evaluated by appropriate statistical methods. Virgin and sexually active F344 rats displayed monolateral or bilateral Leydig cell tumors. There was no statistical difference between the two groups. Despite the early difference between breeding and virgin F344 rats, a control experiment failed to disclose an effect of sexual activity on the occurrence of Leydig cell cancers. This disease displays some difference in incidence in various parts of the world, with the higher socioeconomic groups having a greater incidence. Etiological factors on the occurrence of this disease in animals and in humans remain to be discovered.


Assuntos
Transformação Celular Neoplásica , Tumor de Células de Leydig/patologia , Animais , Endogamia , Tumor de Células de Leydig/epidemiologia , Tumor de Células de Leydig/genética , Masculino , Ratos , Ratos Endogâmicos F344 , Comportamento Sexual Animal
16.
Exp Anim ; 50(2): 99-103, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11381627

RESUMO

Neoplastic lesions were observed in untreated aged Sprague Dawley (SD) rats throughout their lifespan starting at 5 weeks. Their mean survival times were 89 to 105 weeks of age. The total tumor incidences were 70 to 76.7% and 87 to 95.8% in males and females, respectively. The common neoplasmas were pituitary adenoma and adrenal pheochromocytoma in both sexes, testicular Leydig cell tumor in males and mammary gland tumors, thyroidal C-cell adenoma and uterine stromal polyp in females.


Assuntos
Envelhecimento , Neoplasias/veterinária , Doenças dos Roedores/epidemiologia , Adenoma/epidemiologia , Adenoma/veterinária , Neoplasias das Glândulas Suprarrenais/epidemiologia , Neoplasias das Glândulas Suprarrenais/veterinária , Animais , Feminino , Tumor de Células de Leydig/epidemiologia , Tumor de Células de Leydig/veterinária , Masculino , Neoplasias Mamárias Animais/epidemiologia , Neoplasias/epidemiologia , Feocromocitoma/epidemiologia , Feocromocitoma/veterinária , Neoplasias Hipofisárias/epidemiologia , Neoplasias Hipofisárias/veterinária , Pólipos/epidemiologia , Pólipos/veterinária , Ratos , Ratos Sprague-Dawley , Neoplasias Testiculares/epidemiologia , Neoplasias Testiculares/veterinária , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/veterinária , Neoplasias Uterinas/epidemiologia , Neoplasias Uterinas/veterinária
17.
Med Hypotheses ; 50(6): 525-9, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9710329

RESUMO

Recently, an increase in pituitary tumor (pars distalis adenoma) incidence, and decrease in testicular interstitial cell tumor incidence, has been noted in F344 rats, in 2 year National Toxicology Program dermal and inhalation studies. One of the factors that may have contributed to this correlation is the difference in housing protocols. Rats in inhalation and dermal toxicity studies are singly caged, in contrast to other types of studies in which rats are group-caged, such as dosed-feed, dosed-water, or gavage studies. We propose that stress, related to individual caging, particularly among males, directly impairs testosterone synthesis and produces Leydig cell atrophy which leads to a feedback increase in the synthesis of luteinizing hormone by the anterior pituitary. This is followed by anterior pituitary cell functional hypertrophy, hyperplasia, and eventually neoplasia. It is known that individual caging of male rats produces a stress response associated with increased serum corticosteroids. The testicular interstitial cells (Leydig cells) have specific receptors for the glucocorticoid hormones. The Leydig cell enzyme 11-beta-hydroxysteroid dehydrogenase (11-beta-HSD) inactivates gluococorticoids; however, prolonged stress depletes this enzyme, enabling the gluococorticoids to impair steroidogenesis and eventually to lead to compensatory pituitary proliferations, including neoplasms.


Assuntos
Abrigo para Animais , Tumor de Células de Leydig/epidemiologia , Modelos Biológicos , Neoplasias Hipofisárias/epidemiologia , Meio Social , Estresse Fisiológico/complicações , Neoplasias Testiculares/epidemiologia , Corticosteroides/fisiologia , Animais , Sistema Hipotálamo-Hipofisário/fisiologia , Incidência , Masculino , Ratos , Ratos Endogâmicos F344 , Reprodução , Fatores de Risco , Testosterona/fisiologia
18.
Cancer ; 73(2): 388-93, 1994 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8293405

RESUMO

BACKGROUND: The rarity of testis tumor in black patients has made the study of a large series difficult. Much of the epidemiologic and clinical information regarding this neoplasm in this population is in dispute, including data on incidence, prognosis, histologic distribution, age and stage at presentation, and side distribution. METHODS: A retrospective review of 66 blacks with testicular tumors from seven military medical centers was performed. RESULTS: Similar results were found for blacks with testis tumor to those of the general testis cancer population regarding prognosis, side distribution, and age of onset for nonseminoma and interstitial tumors. There is a slight increase in the expected number of interstitial tumors in blacks, but the distribution between seminoma and nonseminoma is similar to the general population. The mean age of presentation for seminoma in blacks was younger than that of the general testis cancer population. For testis tumor treated at the same institution, there was an increased delay of diagnosis in blacks compared with whites. The number of new cases of testicular cancer between 1979 and 1991 at one major center was increased for whites but not for blacks. The availability of cisplatin-based combination chemotherapy has resulted in an improved prognosis for blacks, as has already been demonstrated for white populations. CONCLUSIONS: Testis tumor in blacks behaves similarly to testis tumor in the general population except that in blacks there are more interstitial tumors and the mean age of presentation for seminoma is younger. Further, there is an increased delay in diagnosis for blacks compared with whites, but the incidence of this tumor in this population does not appear to be increasing. Cisplatin-based chemotherapy has significantly improved survival in this population.


Assuntos
População Negra , Neoplasias Testiculares/epidemiologia , Adulto , Fatores Etários , Cisplatino/uso terapêutico , Humanos , Tumor de Células de Leydig/epidemiologia , Masculino , Prognóstico , Seminoma/epidemiologia , Tumor de Células de Sertoli/epidemiologia , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/tratamento farmacológico , Estados Unidos/epidemiologia
19.
Ann Endocrinol (Paris) ; 51(5-6): 194-201, 1990.
Artigo em Francês | MEDLINE | ID: mdl-2130759

RESUMO

One hundred and twenty six reported cases of ovarian tumors located in the hilus (OTLH) are analyzed. They represent a special sub group of ovarian steroid cell tumors (former "lipid cell tumors"). A number of these neoplasms are Leydig-Berger cell tumors (LBCT), which are characterized by the presence of the crystal of Reinke, a specific proteinaceous inclusion, whose detection may be improved by new available methods. Crystal-free steroid cell tumors located in the hilus are in most cases true leydigoma of the ovary whose features are indiscernible from LBCT's. They are revealed after years of evolution by signs of hyperandrogeny or post menopausal bleeding. Plasma testosterone levels are always elevated while urinary 17 keto steroid cytoplasmic values are normal in 50% of cases. Three main features distinguish ovarian tumors located in the hilus from others ovarian steroid cell tumors: the occurrence in aged women, the small size of the tumors, and the excellent prognosis.


Assuntos
Tumor de Células de Leydig/patologia , Neoplasias Ovarianas/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Tumor de Células de Leydig/epidemiologia , Tumor de Células de Leydig/cirurgia , Pessoa de Meia-Idade , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/cirurgia
20.
Trop Geogr Med ; 41(4): 358-60, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2635452

RESUMO

Non-germ cell testicular tumours are reported to be more common in peoples of Negroid and Asian descent than in Caucasians. This group of tumours comprised seven of sixteen testicular tumours seen in a ten-year period at the University of Benin Teaching Hospital, Benin City, Nigeria. However, unlike experiences elsewhere in Africa and the West Indies where paratesticular tumours accounted for a majority of these tumours, malignant lymphomas constituted over 70% of non-germinal testicular tumours in our population.


Assuntos
Tumor de Células de Leydig/epidemiologia , Linfoma/epidemiologia , Rabdomiossarcoma/epidemiologia , Neoplasias Testiculares/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Humanos , Incidência , Lactente , Tumor de Células de Leydig/etiologia , Linfoma/etiologia , Masculino , Pessoa de Meia-Idade , Nigéria/epidemiologia , Rabdomiossarcoma/etiologia , Neoplasias Testiculares/etiologia , Infecções Tumorais por Vírus/complicações
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