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.

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.

Fibrous hamartoma of infancy: an ultrastructural study.

The fine structures of three fibrous hamartomas of infancy were studied. All three components of these lesions were examined. The principal cells in the fibrous and myxoid areas were fibroblasts. Cells with stellate cytoplasmic projections were more prominent in myxoid areas. Myofibroblasts were abundant in two cases and not in the other. The adipose tissue component was formed by lipocytes and occasional preadipose fibroblasts. Blood vessels were more numerous in myxoid areas. Larger vessels were accompanied by smaller vessels and by clusters of cells with primitive junctions, suggesting early blood vessel formation. Some small vessels were surrounded by concentric layers of mesenchymal cells, as if attempting to form media. Electron microscopy seems to confirm the hamartomatous nature of fibrous hamartomas of infancy. The lesion appears to recapitulate the formation of blood vessels and fat, as seen in fetal tissues. Cellular myxoid areas showed prominent vasoformative proliferation, which decreased in the adipose tissue and was least prominent in the dense fibrous component. The latter may represent the end stage of the fibrous proliferation.

Spindle cell sarcoma of scrotum.

Sarcomas of paratesticular origin are rare tumors. They usually manifest themselves as a scrotal mass that should be differentiated from testicular tumors. There are problems regarding their pathologic diagnosis and treatment. We report a case of spindle cell sarcoma of the gubernaculum testis in a young patient. Electron microscopy was used in the histogenetic typing of this tumor.

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.

Giant scrotal hemangioma with azoospermia.

We report a case of giant scrotal hemangioma with azoospermia, which was 37 cm in maximum circumference and 20 cm in length along the raphe. The biopsy specimens of the testes were examined histologically and cytologically. The testicular damage was believed to be due to the heat generated by hemangioma.

Intrascrotal rhabdomyosarcoma.

Rhabdomyosarcoma is the most frequent spermatic cord tumor of infants, children, and young adults, but also occurs as a primary tumor in the testis, epididumis, and testicular tunics. In the last fifteen years, 7 patients with intrascrotal rhabdomyosarcoma were treated at our institution, and an additional 155 cases were found on review of the English literature. On the basis of these 162 cases, incidence and survival statistics were calculated with particular attention to employed forms of therapy. An over-all survival of greater than 73 per cent should be obtainable with proper utilization of surgery, radiation therapy, and combination chemotherapy.

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.

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.

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.

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.

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.

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.

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.