Liposarcoma of the spermatic cord: a report of two cases.

Liposarcomas of the spermatic cord are unusual and rarely reported in the literature. These tumours can sometimes be mistaken for the common scrotal swellings such as hydrocoeles and hernias. Careful clinical and radiological examination will help in appropriate preoperative planning and surgery by an experienced surgical team. We report our experience of two cases of such scrotal swellings.

Angiomyofibroblastoma-like tumor (cellular angiofibroma) in the male inguinal region.

Angiomyofibroblastoma-like tumor is a rare mesenchymal tumor involving the male genital tract. We report a case of an angiomyofibroblastoma-like tumor that arose in the subcutaneous tissue of the left inguinal region in a 50-year-old man. Ultrasonography of the region demonstrated a well-circumscribed subcutaneous mass. Intralesional fat was revealed on magnetic resonance images. Although these imaging features are nonspecific, radiological findings enable considering the diagnosis of angiomyofibroblastoma-like tumor.

Malacoplakia and spermatic granuloma complicating vasectomy.

Malacoplakia is a granulomatous disease with a histiocytic infiltrate containing calcified structures called Michaelis-Gutmann bodies. These structures are considered to represent an abnormal response to infection involving defective lysosomes and abnormal microbubular assembly. The disease most frequently involves urinary and genital tracts, but has also been described from most other organs. Here we present the first case of malacoplakia only involving the vas deferens.

Nine cases of granular cell tumors in B6C3F1 mice.

The histological characteristics of 9 cases of granular cell tumors (GCTs) observed in B6C3F1 mice were examined to determine their cellular origin. Seven of the 9 cases were found in the uterus and other 2 cases were in the subcutaneous tissue. Tumor cells had abundant granules in the cytoplasm which were stained with PAS and were resistant to diastase treatment. Ultrastructurally, the granules were identified as lysosomes. The cell surface had cytoplasmic processus showing interdigitation with adjacent cells. A character feature of the tumor cells was the presence of a desmosome-like structure on their cell surface but no basal lamina was demonstrated. Although GCTs have been considered to be derived from Schwann cells on the basis of their ultrastructural features and S-100 protein-immunopositive findings, the absence of basal lamina in the present cases may raise a controversy as to their origin.

Male adnexal tumour of probable Wolffian origin occurring in a seminal vesicle.

AIMS: Adnexal tumours of probable Wolffian origin are rare low-grade malignant neoplasms that have been previously described in the broad ligament, ovaries and retroperitoneum of females. All are characterized by small, bland epithelial cells growing in a diffuse, trabecular, or tubular pattern. The majority of the cases reported have pursued a benign clinical course. However, recurrences and distant metastases have been described. We present a case of a male adnexal tumour of probable Wolffian origin occurring in the left seminal vesicle of a 29-year-old man with 23 years of follow-up. RESULTS: The diagnosis is supported by immunohistochemical and electron microscopic findings: The tumour cells were immunoreactive for cytokeratin and vimentin while smooth muscle antigen and S100 protein were uniformly negative. By electron microscopy cells were arranged in an acinar pattern and surrounded flocculent, electron-dense material. Individual cells contained numerous dense bodies and free ribrosomes. The patient had recurrences at 14 and 23 years after initial diagnosis. CONCLUSION: This is the first report of this entity in a male. The literature on this unusual tumour is reviewed and the clinicopathological, immunohistochemical and ultrastructural features are described. The differential diagnosis of this seemingly indolent tumour is discussed with genitourinary tumours having a more aggressive clinical course.

A spontaneous seminal vesicle adenocarcinoma in an aged F344 rat.

A rare seminal vesicle adenocarcinoma was found in a 109-wk-old Fischer 344 (F344) rat. At necropsy, the right seminal vesicle was enlarged, containing a 15- x 18- x 18-mm mass. The neoplasm occupied almost the entire seminal vesicle lumen and consisted of epithelial cells arranged in papillary, glandular, and solid patterns. Tumor cells were larger than their normal counterparts in the seminal vesicles and had round nuclei and abundant cytoplasm. Clusters of macrophagelike cells with less abundant cytoplasm and indented nuclei were apparent in the lumina of the glandular structures formed by the tumor cells. No metastasis to other tissues or organs was observed. Immunohistochemically, tumor cells were positive for keratin and S-100, and the macrophagelike cells bound antibodies against vimentin and ED-1. Ultrastructurally, the tumor cells exhibited many small secretory granules, some microvilli, and intercellular junctions. The macrophagelike cells, in contrast, were characterized by lysosomes and abundant rough endoplasmic reticulum. Therefore, a diagnosis of seminal vesicle adenocarcinoma with intraluminal macrophage infiltration was made. This is the first case report of such a seminal vesicle tumor in an F344 rat.

Müllerian adenosarcomalike tumor of the seminal vesicle. A case report with immunohistochemical and ultrastructural observations.

A müllerian adenosarcomalike tumor of the seminal vesicle is described in a 49-year-old man. The tumor occupied the entire right seminal vesicle and adhered to the right lobe of the prostate, in the area adjacent to the seminal vesicle. The tumor was also adherent to the rectum. Microscopically, the cells were seen to invade the prostatic tissue. The tumor consisted of a highly cellular stroma with spindle-shaped pleomorphic cells, suggesting the diagnosis of a low-grade sarcoma. In addition, dilated cystic spaces lined by columnar epithelium were seen. Immunohistochemically, most tumor cells showed positivity for vimentin, desmin, and muscle-specific actin, suggesting smooth-muscle cell differentiation. Furthermore, electron microscopy also demonstrated smooth-muscle differentiation of the tumor cells. The patient has been disease-free for 48 months since undergoing a cystoprostatetectomy.

Elastin in adenomatoid tumor. Light microscopic and electron microscopic study.

Elastin distribution was examined in adenomatoid tumors of the human genital tract. Two distinct patterns were identified: strongly positive or completely negative for elastin in the stroma, according to the case. Even in cases appearing to have very similar histologic features, the stroma was rich in elastin in some cases and was almost devoid of elastin in others. Electron microscopic examination with tannic acid staining revealed that the elastin in the stroma was composed mainly of amorphous material surrounded by a small amount of microfibrils and abundant collagen fibers. Fibroblasts were sparsely distributed in the stroma. Tumor cells displayed mesothelial cell-like features, such as abundant microvilli on the surface, numerous cytoplasmic organelles, several well-developed basal lamina. In some areas, elastin seemed to be formed by mesothelial cells. In some adenomatoid tumor cases, elastogenesis would be enhanced by activated mesothelial tumor cells as well as stromal fibroblasts.

Sonography of intrascrotal adenomatoid tumor.

A case is reported of an adenomatoid tumor of the epididymis. A discussion of the appropriate differential of mass of the epididymis as well as a review of adenomatoid tumors per se and their occurrence in the scrotum are presented.

Paraganglioma of the spermatic cord. Report of a case with immunohistochemical and ultrastructural studies.

We describe a case of paraganglioma arising in the spermatic cord, which is an extremely rare location. Immunohistochemical studies characterized two types of cells: (1) polygonal cells expressing neuron-specific enolase, chromogranin A, and synaptophysin and (2) S100 protein-positive sustentacular cells. Electron microscopy revealed that within the cytoplasm of the polygonal cells, there were electron-dense granules whose morphological appearance was consistent with that of neurosecretory granules. Paraganglioma of the spermatic cord may originate from embryonic chromaffin cells that have followed the testis into the scrotum.

Carcinosarcoma of the spermatic cord.

The first case of carcinosarcoma in the spermatic cord is reported in a 40-year-old man. The tumor was a 2.5 X 2 cm pseudoencapsulated formation located in the connective tissue of the spermatic cord among the blood vessels. Light microscopy examination of the neoplasm revealed two different histological patterns: epithelial and sarcomatous. Mitoses and atypias were infrequent in both types of areas. The epithelial cells formed papillary and gland-like structures stained with PAS, Hale and mucicarmine stains, and showed positive reaction for immunohistochemical demonstration of both keratin and epithelial membrane antigen. The lumen content of the gland-like structures reacted positively for the carcinoembryonic antigen. Electron microscopy revealed that the epithelial cells were joined by junctional complexes and displayed numerous short microvilli. The sarcomatous areas consisted of spindle cells embedded in a ground substance that occasionally presented myxoid changes. Mast cells and focal calcifications were seen. Sarcomatous cells showed positive reaction for vimentin but not for the other histochemical and immunohistochemical techniques mentioned above. The ultrastructure of sarcomatous cells was similar to that of epithelial cells except for the occurrence of small desmosomes instead of junctional complexes. The differential diagnosis with adenomatoid tumor and malignant mixed mesothelioma is discussed.

Cystic epithelial-stromal tumor of the seminal vesicle.

A cystic tumor composed of atypical glands in a cellular stroma arose in the pelvis of a 49-year-old man. Two years later an identical tumor was again excised from the pelvis. Morphologic, immunohistochemical and ultrastructural studies indicate that this neoplasm arose in the seminal vesicle, possibly from a seminal vesicle cyst. The tumor did not involve the prostate gland, and immunohistochemical stains for prostate-specific antigen and prostatic acid phosphatase were negative. Ultrastructural study showed that both the glandular and mesenchymal components of the tumor recapitulated features of normal seminal vesicle, further establishing origin from this site. This tumor resembles the rare cystadenoma of the seminal vesicle, yet the cytologic atypia suggests low grade malignant potential. Following the second excision, the patient has had a disease-free interval of 18 months. Long term follow-up and recognition of additional cases is necessary to define the biologic potential of this unusual tumor.

The ultrastructure of selected gynecologic neoplasms.

Several articles have been published recently that discuss the role of electron microscopy in the diagnosis and study of gynecologic neoplasms. It becomes apparent from those works and the review just presented that, although an ultrastructural study is not necessary for reaching a diagnosis of many of these tumors, it may be necessary or supportive in identifying the more poorly differentiated ones. Furthermore, electron microscopy is valuable in providing evidence for the histogenesis of some of these neoplasms. Unfortunately for the pathologist, a certain level of morphologic differentiation (and an absence of metaplasia) in a cell is usually necessary for these goals to be achieved. For example, an adenomatoid tumor (see the article by Dr. Srigley, Mr. Toth, and Mr. Edwards in this issue) of the fallopian tube can readily be accepted as being composed of mesothelial cells, because both the neoplastic cells and normal mesothelial cells have the same highly differentiated features of long, slender microvilli, prominent intercellular junctions, and many microfilaments. On the other hand, there is very little resemblance between the granulosa cells of a granulosa-cell tumor and mature mesothelial cells. Thus, if one of the theories of histogenesis of granulosa cells were correct--namely, that they are derived ultimately from mesothelial lining--the ultrastructural evidence would rest on recognizing a similarity between the two types of cells at an earlier stage of differentiation. The neoplastic granulosa cell has differentiated along a separate, specialized line in which the ultrastructural resemblance to the parent cell is partly, if not completely, lost. Another example of the type of information that electron microscopy can provide is in relation to the common epithelial tumors. There is good evidence that the serous tumors in this group arise from mesothelium, although ultrastructurally their differentiation has veered from a mesothelial direction to one in which the cells have a complement of organelles related to secretory activity. Paradoxically, the mucinous cystic tumors, which have been classified traditionally as tumors of surface epithelial origin, are now thought to be of germ-cell origin in some cases, as examples of monophyletic teratomas. The ultrastructural evidence for this conclusion rests on the presence of anchoring filaments in the microvilli of the neoplastic cells, similar to those of normal intestinal epithelium, and on an admixture of various types of gastrointestinal cells, including those that contain dense-core granules (argentaffin cells).(ABSTRACT TRUNCATED AT 400 WORDS)

Diagnostic electron microscopy of male genital tract tumors.

As illustrated in this review, neoplasms of the male genital tract are markedly heterogenous, reflecting their complex embryologic derivation and histogenetic classification. Transmission electron microscopy has greatly increased our understanding of the structure of these tumors, and in doing so has greatly improved our light microscopy. Additionally, in a number of selected situations, TEM also provides important practical diagnostic information. Currently, light microscopy in conjunction with clinical information is the central tool of tumor taxonomy. However, TEM with histochemistry, immunohistology, analytic cytometry, and molecular biology provide practical and useful information in some situations. In all cases, the application of these techniques has greatly increased our overall understanding of tumor structure, pathobiology, and classification.

Recurrent dedifferentiated liposarcoma of the spermatic cord simulating malignant fibrous histiocytoma: an immunohistochemical and ultrastructural study.

A case of recurrent dedifferentiated liposarcoma simulating malignant fibrous histiocytoma, with complete absence of lipoblastic differentiation, is described. The tumour cells showed strongly positive immunostaining for alpha-1-antichymotrypsin. Electron microscopy revealed a mixture of fibroblasts and histiocytes. Our findings suggest that the dedifferentiated component reflects an altered differentiation pathway of the primitive mesenchymal cells in the original liposarcoma.

Adenomatoid tumours: an immunohistochemical and ultrastructural appraisal of their histogenesis.

The histogenesis of adenomatoid tumour has continued to provoke debate since Golden and Ash suggested the term in 1945 for a characteristic benign neoplasm typically found in the uterus, fallopian tube or epididymis. Endothelial, epithelial, mesonephric, müllerian and mesothelial histogenesis have been suggested. The balance of evidence suggests mesothelial derivation, but two recent studies point to endothelial origin for at least some of these tumours. Twenty-two histologically typical adenomatoid tumours were studied by electron microscopy, mucin histochemistry and immunohistochemistry. Ultrastructurally, all cases showed vacuolated cells bearing long bushy microvilli and the features were not those of endothelial cells. Glandular spaces contained acid mucopolysaccharide consistent with hyaluronic acid. Immunohistochemical double labelling techniques showed the cells lining such spaces to contain cytokeratin in the absence of factor VIII related antigen and receptors for Ulex europaeus I lectin which were expressed in the endothelium of tumour blood vessels. The evidence points to mesothelial histogenesis in all cases examined.

Buschke-Loewenstein tumour. A histologic and ultrastructural study of six cases.

Results on the light- and electron microscopic studies of six cases of Buschke-Loewenstein tumour are presented. The role of chronic irritation is emphasized in the aetiology of the tumour. Fistulas and abscesses arising in the tumour are dangerous as they give rise to chronic sepsis. In two perianal tumours, in situ or invasive carcinoma developed. Electron microscopy revealed varying degrees of differentiation of keratinocytes. As a result of the defective desmosomes, the tumour cell underwent segregation, with widened intercellular spaces containing oedema, erythrocytes and leucocytes. This phenomenon is probably responsible for frequent bleeding and fistula formation. The investigations disclosed that the Buschke-Loewenstein tumour is a special form of squamous carcinoma and therefore, radical surgical excision must be attempted even in case of a benign histological picture.

Unusual intracytoplasmic lamellar bodies in a malignant gonadal stromal tumor.

Characteristic intracytoplasmic lamellar bodies were found in a malignant gonadal stromal tumor. These bodies consisted of the stacks of up to 200 tubular cisternae arranged in parallel. Each cisterna had a circular section in tangential view and a diameter of about 85 nm. The cisternae on the outermost side of these lamellar bodies tended to be dilated and adorned with ribosomes. The ends of cisternae were often contiguous with rough-surfaced endoplasmic reticulum. The latter feature is also seen in annulate lamellae, but periodically spaced annuli or discontinuities characteristic of annulate lamellae were never observed. Furthermore, fine ribosomal granules resembling a rosary were recognizable along the whole circumference of the outer surface of each cisterna. The unique structure we describe is a cytoplasmic organelle which, like annulate lamellae, is closely associated with the endoplasmic reticulum and is presumed to be related to the genesis of rough-surfaced endoplasmic reticulum in tumor cells.