Mucinous cystadenoma of the testis

A 35-year-old man complained of a painless enlargement of the right testis. Imaging diagnostic procedures demonstrated a multiloculated cystic tumor, 9 cm in maximal diameter, in the right testis with hydrocele. Orchidectomy specimen showed that the tumor was confined within the testis and separated from the epididymis. The locules of the tumor were lined by single-layered columnar epithelium, intermingled with MUC2 immunopositive goblet and chromogranin-A immunopositive neuroendocrine cells, exhibiting intestinal differentiation. No ciliated cell, teratomatous element or intratubular germ cell neoplasia were seen. Channels of rete testis were compressed peripherally by the tumor but there was no connection with the tumor locules. The tumor was diagnosed as mucinous cystadenoma of the testis. This seems to be the first published case of benign mucinous cystadenoma occurring within the testis. This intratesticular tumor with intestinal differentiation may represent a benign monodermal teratoma.     

Intertubular growth in pure seminomas: associations with poor prognostic parameters

Clinical stage I seminomas are effectively treated with surgery raising concerns as to when to give adjuvant radiation therapy given the risk of secondary malignancies. A recent randomized trial found tumor size and rete testis invasion to be the strongest predictors of relapse in clinical stage I seminomas. These 2 parameters may be surrogate measures of tumor volume. Intertubular seminoma (ITS) of the testis describes the presence of neoplastic germ cells within the interstitium of the testis. These cells are detected away from the main macroscopic mass. Because ITS can infiltrate in a 3-dimensional fashion, it may also represent a measure of tumor volume not usually noted in standard pathology reporting. The goal of this study was to determine the incidence of ITS in pure seminomas and its association with other prognostic parameters. One hundred twenty consecutive pure seminomas surgically removed between 1998 and 2003 were evaluated. ITS was defined as the presence of an interstitial or intertubular growth pattern of tumor cells, which was noncontiguous with the main tumor and present at least 3 high-power fields away from the tumor mass. The average tumor size was 3.4 cm. Of the entire cohort of patients, which included pathological stages T1 through T3, 11% had invasion through the tunica albuginea, 51% had rete testis invasion, 51% had lymphovascular invasion, 93% had associated intratubular germ-cell neoplasia, and 36% had ITS. ITS was significantly associated with rete testis invasion ( P = .001). Logistic regression analysis looking at ITS, tumor size, patient age, and lymphovascular invasion revealed that only ITS was associated with rete testis invasion (RR, 4.1, P < .0001). ITS is present in a significant proportion of pure seminomas and has a significant association with rete testis invasion. The presence of ITS may therefore be an important prognostic factor, not only because it alters the calculated size of the tumor but also because it has an association with rete testis invasion.     

Clear cell adenocarcinoma of the tunica vaginalis of the testis with an adjacent uterus-like tissue

Testicular and paratesticular neoplasms that resemble the common epithelial type of ovarian tumor are quite rare. Paratesticular clear cell carcinoma is very uncommon in the testis, with no reported cases of a tumor arising from the tunica vaginalis in the literature to our knowledge. The present case shows that it is highly malignant and metastatic. The differential diagnosis of the tumor was made after thorough clinical, pathological and immunohistochemical investigations, from the mesothelioma of the tunica vaginalis, paratesticular serous papillary carcinoma, carcinoma of the rete testis, epididymal adenocarcioma, yolk sac tumor of the testis and metastatic carcinoma. The tumor showed Bcl-2 and Her-2/neu immunoreactivity, but was non-reactive for p53. This tumor, with a uterus-like structure as a paratesticular tumor-like mass, was composed of endometrial-type glands and stroma surrounded by bundles of smooth muscle, and is the third example of this kind of structure in English written literature. The patient, having normal external genitalia and fertility, represents the first reported case of paratesticular malignant differentiation of müllerian-type epithelium in the normal gonadal state. Müllerian-type epithelium located in the vicinity of the testis and/or endometriotic metaplasia of the mesothelium of the tunica vaginalis might be the possible origins for this uterus-like structure, and as a result, for this tumor.     

Adenofibroma of the rete testis. A case report with electron microscopy findings

The light and electron microscopic characteristics of an adenofibroma of the rete testis in a 51-year-old man are described. The tumor was 5.5 cm in greatest diameter and situated in the anterior superior portion of the right testis. It was composed mainly of mesenchymal and secondary epithelial proliferation. Long slit-like spaces and short tubules lined by a layer of epithelial cells were seen in the mesenchymal tissue. The epithelium was histochemically and ultrastructurally similar to that of the rete testis, and the tumor was considered to be of rete testis origin.     

Testicular juvenile granulosa cell tumor in a newborn: case report and review of the literature

Juvenile granulosa cell tumor of the testis of neonates and infants is an uncommon lesion frequently associated with abnormal sex chromosome and ambiguous genitalia. This report describes a juvenile granulosa cell tumor arising in the testis of a neonate. Chromosome analysis of the tumor showed a normal male karyotype 46 XY. Histopathology and immunohistochemical studies revealed the occurrence of 2 well-differentiated epithelial-like and smooth muscle-like components in the neoplasm. The morphologic clues leading to the correct diagnosis of juvenile granulosa cell tumor and the possible histogenesis are briefly discussed.     

Testicular granulosa cell tumor, adult type

Granulosa cell tumor (GCT) of the adult type is a rare and slow-growing neoplasm in the testis. This tumor may be associated with endocrine manifestations and resemble classic GCT of the ovary morphologically. It has a potential for distant metastasis or recurrence late in the clinical course. We report a case of granulose cell tumor of the testis, adult type.     

Primary neuroendocrine tumor of the testis: a study of clinicopathological features

This study aimed to explore the clinicopathological characteristics and differential diagnosis of primary neuroendocrine tumor (G1) of the testis. In this paper, we analyze the clinical, histomorphological and immunohistochemical findings, treatment and prognosis of a patient with primary neuroendocrine tumor of the testis, and discuss the relevant literature. A 52-year-old man presented with a painless testicular swelling since 6 months. Histopathological examination showed that the tumor cells were arranged in island and beam patterns. The tumor cells were uniform, polygonal and had moderately eosinophilic cytoplasm and fine granular nuclear chromatin. Immunohistochemical staining showed that the tumor cells were positive for cytokeratin, CD56, synaptophysin and chromogranin A, and negative for inhibin, placental alkaline phosphatase and alpha-fetoprotein. Primary neuroendocrine tumor of the testis is a rare tumor with characteristic imaging features. Its accurate diagnosis depends on the morphological and immunohistochemical findings. These tumors should be differentiated from metastatic neuroendocrine carcinomas, teratomas with carcinoid, seminomas, Sertoli cell tumors and granulosa cell tumors. The treatment of most primary neuroendocrine tumors involves surgical resection combined with other therapies and usually results in a good prognosis.     

Ultrastructure of metastatic rete testis adenocarcinoma

Adenocarcinoma of the rete testis is a rare tumor. We describe the ultrastructural appearance of a retroperitoneal adenocarcinoma metastatic from the rete testis, and compare this appearance with that of normal human rete testis. Both normal rete epithelium and the tumor showed deep, narrow nuclear invaginations with apparent nuclear lobulation; small, pleomorphic, electron-dense, membrane-bound granules in the basal cytoplasm; lipid droplets in the apical cytoplasm; and distinctive bulbous cytoplasmic projections along the apical surfaces of the cells. In addition, more general features of glandular tissue were seen. Features notable for their absence were mucin granules, microvilli containing filamentous cores, glycocalyx, and glycocalyceal bodies. The ultrastructural appearance was sufficiently distinctive to suggest that, in the proper clinical context, electron microscopy may serve to support a diagnosis of adenocarcinoma of the rete testis.     

Adenocarcinoma of the rete testis: A review of the literature and presentation of a case with associated asbestosis

Although scattered reports of adenocarcinoma of the rete testis have previously appeared and criteria for the diagnosis of this tumor have been defined, previous cases have not been described in sufficient detail to provide an organized account of the nature and behavior of this neoplasm. The present report describes a case followed to autopsy and provides conclusive evidence that it is of rete testis origin. Previously reported cases of rete testis carcinoma are reviewed and the salient features summarized, showing that the tumor has a definite clinical and histologic pattern and that the prognosis appears poor. The present case occurred in a patient with severe pulmonary asbestosis. This association is unique, and its significance remains speculative.     

Primary adenomatoid tumor of the testis: report of a case and review of literature

Adenomatoid tumor (AT) is an extremely rare benign tumor in the testis of infants. A case of 14-month-old boy with testicular adenomatoid tumor was reported in this study. On physical examination, a smooth solid nodule sized 8 mm could be palpated with little tenderness on the head of the right testis. It could be clearly revealed by B ultrasonic scanning and computerized tomography. The patient underwent right radical orchiectomy. In postoperative histopathological study, the tumor was characterized by diffuse sheets of epithelioid cell and desmo-stroma structures. There was positive immunohistochemical staining of mesothelioma-associated antigens. The tumor should be differentiated from the tumor of the male genital tract including benign and malignant tumors of both epithelial and stromal origin. And we followed the case and no nodule was found in his scrotum by physical examination and scrotal ultrasonography after 3, 6, 12, 18, 24, 30, 36, 42, 48, 54, 60 months. These findings have important implications that the histogenesis of adenomatoid tumor of the testis is unclear yet. The diagnosis depends on pathologic studies, and should be differentiated from paratesticular malignant mesothelioma and sclerosed lipogranuloma. Radical surgery is the common choice, and as a result of getting a good prognosis.     

A spontaneous teratocarcinoma in the testis of a swiss albino mouse

A unilateral non-metastatic embryonal carcinoma and teratoma of the testis was observed in a 12-week-old Swiss Albino mouse at the end of a 28-day repeated dose toxicity study. The teratocarcinoma almost completely replaced the parenchyma of the left testis. The tumor was composed of sheets and rosettes of primitive embryonal cells, anaplastic cells, skeletal muscle tissue, sebaceous gland tissue, keratinized stratified squamous epithelium, and ciliated cuboidal epithelium. The histomorphological characteristics of the tumor were reviewed and presented in this report. To the best of the authors' knowledge, this is the first report of spontaneous teratocarcinoma of testis in the Swiss Albino strain of mice.     

ADENOFIBROMA OF THE RETE TESTIS: A Case Report with Electron Microscopy Findings

The light and electron microscopic characteristics of an adenofibroma of the rete testis in a 51-year-old man are described. The tumor was 5.5 cm in greatest diameter and situated in the anterior superior portion of the right testis. It was composed mainly of mesenchymal and secondary epithelial proliferation. Long slit-like spaces and short tubules lined by a layer of epithelial cells were seen in the mesenchymal tissue. The epithelium was histochemically and ultrastructurally similar to that of the rete testis, and the tumor was considered to be of rete testis origin. ACTA PATHOL JPN 38: 105–112, 1988.     

Hemangioma of the testis: report of unusual occurrences of cavernous hemangioma in a fetus and capillary hemangioma in an older man

We report two cases of hemangiomata of the testes which occurred in a 17-week-old fetus and a 73-year-old man. To our knowledge, these are the first reported cases of cavernous hemangioma of the testis in a fetus and capillary hemangioma of the testis in an older man. Although a hemangioma of the testis is rare, it should be considered in the differential diagnosis of a testicular tumor. Ann Diagn Pathol 5:80-83, 2001.     

Sex cord-stromal tumors of the testis

Testicular tumors apart from those in the germ cell family are uncommon and are mostly sex cord-stromal tumors and may pose a major diagnostic challenge. This review focuses on the clinicopathologic features of these uncommon neoplasms, pertinent differential diagnoses, relevant immunohistochemical and molecular findings as well as the recent updates proposed by the World Health Organization (WHO). Contrast between these neoplasms as seen in the male and female gonad will also be made when warranted. The commonest sex cord-stromal tumor of the testis is the Leydig cell tumor which, when seen in children, is often associated with sexual precocity. The histologic features are generally those of an easily recognized oxyphilic neoplasm but various peculiarities such as microcysts and spindling of the tumor cells may case diagnostic difficulty on occasion. In the male, in contrast to the female, the most common sex cord-stromal tumor of epithelial nature is the Sertoli cell tumor. Most of these fall in the not otherwise specified category and are usually characterized by a diagnostically helpful at least focal hollow or solid tubular pattern. Occasional malignant Sertoli cell tumors have a predominantly diffuse pattern sometimes interrupted by septa with a lymphocytic infiltrate that can cause seminoma to be mimicked. Rare Sertoli cell tumors are associated with marked sclerosis. The so-called large cell calcifying Sertoli cell tumor, may be sporadic or associated with manifestations of the Carney syndrome. A distinctive entity referred to as intratubular hyalinizing Sertoli cell neoplasia occurs in the testis of young boys with Peutz-Jeghers syndrome. It is often bilateral, microscopic and associated with gynecomastia. Testicular granulosa cell tumors are much rarer than their ovarian counterparts but can be similarly subdivided into adult and juvenile forms. In the male, the juvenile granulosa cell tumor has a particularly striking tendency to occur in the first 6 months of life. The primitive appearance of the nuclei and brisk mitotic activity of the juvenile granulosa cell tumor may result in a misdiagnosis of a more malignant neoplasm. The histologic spectrum of the adult granulosa cell tumor is as seen in the more common female examples. Pure stromal tumors of the testis are much less common than similar tumors in the ovary and the well-known thecoma is remarkably rare in the testis. Fibromas of stromal derivation in the testis should be distinguished from fibromas that originate from the tunica albuginea and from examples of the non-neoplastic process nodular pseudotumor.     

Immunohistochemical examination of mucinous cystadenoma of the testis

A case of mucinous cystadenoma of the testis in a 55-year-old man is reported. The tumor was confined to the testis and was clearly separated from the epididymis. There was no connection between the tumor cyst and the rete testis. The lumen of the cyst was lined with a single-layer of columnar cells interspersed with goblet cells. There was neither stromal invasion nor metastasis to other organs and there were no ovarian or germ cell neoplastic elements in the tumor. Immunohistochemical analysis revealed that MUC2, MUC5AC, carcinoembryonic antigen, CA19-9, CK7 and CK20 proteins were expressed on the tumor epithelial cells, whereas expression of MUC6, alpha-fetoprotein, CA125, human chorionic gonadotrophin, estrogen receptor, progesterone receptor, calretinin, chromogranin A, p53, cyclin D1 and bcl-2 proteins was absent. Ki-67 protein was weakly and sparsely expressed in the nuclei of epithelial cells. The mucinous cystadenoma in the present case, which was devoid of a connection to testicular appendices and had the immunohistochemical characteristics of gastrointestinal mucosa, might have originated from one-sided differentiation of teratoma cells.     

An in-depth look at Leydig cell tumor of the testis

Leydig cell tumor (LCT) is a rare tumor of the male testicular interstitium. This article provides an overview of the major pathologic manifestations of LCT of the testis; patient characteristics; clinical, radiologic, and laboratory features; prognosis; and management. LCTs of the testis are frequently hormonally active, leading to either feminizing or virilizing syndromes. The tumor is usually benign, but malignant variants can occur. The pathologic diagnosis of LCT is usually made based on morphologic characteristics of the tumor cells. The significance of Reinke crystals in the diagnosis of LCT both cytologically and histologically is underscored. Pathologists have to be familiar with the diagnostic histopathologic features, immunohistochemical panel of this tumor, and its principal differential diagnoses to prevent tumor misdiagnosis.     

Renal cell carcinoma metastatic to the testis and its adnexa: a report of five cases including three that accounted for the initial clinical presentation

Five cases of renal cell carcinoma metastatic to the testis or its adnexa are described, including 3 that represented the initial presentation and mimicked primary testicular neoplasms. The patients ranged from 46 to 85 years of age. Three presented with self-identified testicular masses. One patient was investigated because of fever of unknown origin and was found to have a left rib metastasis. Further work-up led to the discovery of a testicular mass. The final patient had a tumor of the spermatic cord that was examined without knowledge that he had a prior renal neoplasm. All the tumors were unilateral. They ranged from 1.8 to 5.0 cm; multiple tumor nodules were present in one of them but the others were discrete solitary masses. Four tumors were yellow/yellow-tan, and one was gray. On microscopic examination all the tumors were of the clear cell type. Patterns included solid sheets, acini, cysts, alveoli, and trabeculae. Two had prominent vascular invasion. Diagnoses initially entertained in these cases included Sertoli cell tumor, Sertoli-Leydig cell tumor, and clear cell cystadenoma of the epididymis. In 3 cases a kidney tumor was discovered 2 to 4 weeks after the diagnosis of renal cell carcinoma metastatic to the testis was rendered. On follow-up two patients died of tumor, and two were alive (5 months and 1 year) after orchiectomy. The diagnosis of renal cell carcinoma metastatic to the testis should be considered in evaluating a clear cell tumor of the testis, particularly in an older male or if the appearance suggests a Sertoli cell tumor. The differences in survival between metastatic renal cell carcinoma and sex cord-stromal tumors indicate the importance of considering the former in the differential.     

Sertoli-stromal cell tumor of the ovary: immunohistochemical, ultrastructural, and genetic studies

The Sertoli-stromal cell tumor (SSCT) of the ovary shows a histologic resemblance to developing or adult testes and is often associated with virilization caused by tumor-produced androgenic hormone. In spite of the unique manifestation of SSCT, detailed characteristics of this tumor are still obscure. The mechanism by which SSCT occurs has not yet been determined. Six SSCTs were studied immunohistochemically, ultrastructurally, and by polymerase chain reaction (PCR) for the presence of sex-determining region Y (SRY) gene and the X chromosome activation state. Immunohistochemically, Sertoli-like cells of SSCT were positive not only for alpha-inhibin but also low-molecular-weight cytokeratin. In control testes, the expression of alpha-inhibin and cytokeratin was limited to a Sertoli cell component and rete testis, respectively. Ultrastructurally, tumor cells composing hollow tubules had an elongated nucleus with deep indentation and annulate lamellae, which are characteristic structures of mature Sertoli cells. In addition, they had studded microvilli on the apical surface and frequent desmosomes, which are structures noted in the cells of rete testis. Histologically, tumor cells of hollow tubules sometimes pouted into the lumen, as did the cells of tubulae rete, entrance into rete testis from seminiferous tubules. All of these findings indicate that some tumor cells of a SSCT show simultaneous differentiation into both Sertoli cells and cells of rete testis. SRY gene was not detected in any cases, and the X chromosome activation pattern was the same as that of the female control.     

Primary signet-ring stromal tumor of the testis

We present, in a 47-year-old man, the first case of the signet-ring stromal tumor of the testis. The tumor was located beneath the tunica albuginea surrounded by the testicular tubules and rete testis. It was sharply circumscribed by a thin and irregular fibrous capsule. Histologically, it was composed of cells with a widespread signet-ring cell change separated by fibrous stroma. In some places, the signet-ring cells formed vague Indian files, thus resembling metastatic carcinomas with signet-ring cell morphology. Under high magnification, most of the cytoplasm of the tumor cells was seen to be replaced by an empty clear vacuole which pushed the nuclei to the periphery of the cells. Some of the nuclei were indented by the cytoplasmic vacuoles, others were without indentation. Only in a small area did the tumor show cells without a signet-ring cell change. They looked like epithelioid fibroblasts forming abortive and vaguely tubular structures. Mitoses and necroses were absent. Mucicarmine and PAS stains were negative. Immunohistochemically, the tumor was vimentin positive and it was negative with antibodies to cytokeratins, inhibin, prostatic acid phosphatase, prostate-specific antigen, smooth muscle actin, S-100 protein, EMA and calretinin. The signet-ring stromal tumor of the testis is thus similar morphologically and immunohistochemically to the signet-ring stromal tumor of the ovary. The patient was free of recurrence and metastasis 3 years after the excision.     

癌-睾丸抗原基因在神经胶质瘤干细胞中的表达

背景：癌-睾丸抗原基因在胶质瘤干细胞表达还不甚清楚。 目的：检测癌-睾丸抗原基因在神经胶质瘤干细胞中的表达。 方法：通过神经球培养的方法而分离干细胞。以半定量PCR及实时荧光定量PCR检测癌-睾丸抗原基因在母细胞、干细胞与分化细胞中的表达。 结果与结论：以神经球培养方式从胶质瘤细胞系中可分离出肿瘤球,将肿瘤球培养在含血清的培养基中,它的形态呈贴壁分化,且与母细胞没有区别。半定量PCR及实时荧光定量PCR检测发现与母细胞和分化细胞相比,癌-睾丸抗原基因在干细胞中的表达最高。提示癌-睾丸抗原基因可能为肿瘤干细胞的表面抗原。