Expression of N-acetyl-D-galactosamine associated epitope in synovium: a potential marker of glycoprotein production.

OBJECTIVE: To investigate synovial glycoprotein production in situ, a novel monoclonal antibody (Mab), A13D8, was used to evaluate the expression of an epitope containing N-acetyl-D-galactosamine (GalNAc) in normal and pathological synovium. METHODS: Immunohistological and cytochemical analysis of synovial tissue samples was undertaken with single and double staining techniques using the A13D8 Mab, anti-CD68, vascular cell adhesion molecule-1 (VCAM-1), the hyaluronan associated enzyme uridine diphosphoglucose dehydrogenase (UDPGD), and the anti-Golgi Mab SSN/HR-1992. The specificity of the A13D8 Mab was established through blocking studies using carbohydrate residues, including GalNAc and N-acetylglucosamine (GlcNAc). RESULTS: A13D8 is expressed intensely in the cytoplasm of normal type B lining cells, which coexpress VCAM-1 and UDPGD, and is not expressed by CD68+ type A lining cells. In the lining layer of RA synovium, there is a negative correlation between A13D8 expression and the level of lymphocytic infiltration in the sublining areas (r = -0.43, p < 0.001). The endothelium of a subset of venules, typically in lymphocyte-rich aggregates, also stains intensely for A13D8. Pretreatment of the Mab with GalNAc completely eliminates the tissue staining, as well as the 110 kDa band seen on immunoblot, whereas pretreatment of A13D8 with GlcNAc and lactose has no effect. Double staining of HEp-2 cells with A13D8 and the anti-Golgi Mab SSN/HR-1992 reveals co-localization of the A13D8 epitope to the Golgi apparatus. CONCLUSION: Type B synovial lining cells and selected synovial endothelium express GalNAc containing epitope identified by Mab A13D8. Marked reduction in the expression of this epitope in the lining layer of inflamed RA synovium suggests that the synovial production of GalNAc containing glycoproteins, such as mucins, may be altered in this disorder.

Primary cardiac angiosarcoma: clinical and pathological diagnostic problems.

Primary cardiac malignancy is very rare. The most common malignant cardiac tumours are angiosarcomas. Their diagnosis is sometimes difficult because of their nonspecific clinical presentation. Two cases of primary cardiac angiosarcomas that were not diagnosed clinically due to unusual presentations are presented. Pathological diagnosis was missed in one case because of lack of thorough examination and sampling of submitted specimens. Cardiac symptoms in a patient with primary angiosarcoma of the heart may not always be present. In the presence of unusual serious systemic symptomatology, such as multisystemic hemorrhagic phenomena, disseminated infiltrative pulmonary lesions or peripheral tumour associated with subtle heart abnormalities, the possibility of cardiac angiosarcoma should be included in the differential diagnosis.

Subpubic cartilaginous cyst: report of two cases.

We report two cases of an unusual type of subpubic cystic mass occurring in postmenopausal women. They are formed by fibrocartilaginous tissue with extensive cystic degenerative changes and appear to be related to and perhaps originating from the periarticular tissues of the symphysis pubis. We could not find any reference to this lesion either in the standard gynecology and pathology textbooks or in a search of the published literature.

Papillary endothelial hyperplasia of adnexal vasculature.

Papillary endothelial hyperplasia is an exuberant predominantly intravascular endothelial proliferation which may simulate angiosarcoma both clinically and histopathologically. This report describes what, to the best of our knowledge, is a unique case of papillary endothelial hyperplasia within para-ovarian and paratubal veins in relation to a multicystic mesothelial and haemorrhagic ovarian mass. Papillary endothelial hyperplasia should be included in the differential diagnosis of vascular lesions in this site.

Necrobiotic palisading suture granulomas simulating rheumatoid nodule.

Five patients without clinical evidence of rheumatic disease developed postoperative periarticular suture reactions featuring necrobiotic granulomas histologically similar to rheumatoid nodules. Suture granulomas are to be included in the differential diagnosis of palisading granulomas simulating rheumatoid nodule.

Solitary fibrous tumour: report of two new locations in the upper respiratory tract.

Solitary fibrous tumours are uncommon spindle cell neoplasms generally associated with serosal surfaces, especially the pleura ('localized fibrous mesothelioma'). Recently, these tumours have been documented in extraserosal sites. We report two solitary fibrous tumours, including one occurring in the paediatric age group, arising in two previously unreported locations, parapharyngeal space and epiglottis. These cases expand the range of sites where this tumour may originate and confirm the tendency of extrapleural cases to involve the upper respiratory tract and adjacent structures.

Intranodal myofibroblastoma in a submandibular lymph node. A case report.

A typical case of intranodal myofibroblastoma arising in a submandibular lymph node is reported. It provides proof that this tumor can occur in extrainguinal regions and suggests that the submandibular region is a prevalent site. The combination of benign spindle cells and foci of pale fibrillary matrix and hemosiderin granules were characteristic features in the fine-needle aspiration cytologic findings.

Giant cell fibroblastoma recurring as dermatofibrosarcoma protuberans.

A case of giant cell fibroblastoma in an 8-year-old child recurred locally 15 years later with the typical picture of dermatofibrosarcoma protuberans. This sequence of events suggests that giant cell fibroblastoma is a juvenile form of dermatofibrosarcoma protuberans.

Primary alveolar soft-part sarcoma of stomach.

A case of primary gastric alveolar soft-part sarcoma is presented. The tumor was found in the gastric remnant of a 67-year-old male who had undergone partial gastrectomy due to hemorrhagic gastric ulcer 13 years before. It was located mostly in the submucosa arising from the muscularis propria. The large eosinophilic cells showed the characteristic alveolar compartmentalization and contained intracytoplasmic periodic acid-Schiff-positive granules and typical crystals. Numerous electron-opaque secretory granules in the tumor cell cytoplasm, in addition to crystals of 9 nm periodicity, were confirmed at the ultrastructural levels. Immunostaining failed to detect muscle-related antigens. In contrast, methionine-enkephalin and neuropeptide Y appeared positive in the tumor cells. Interstitial spindle cells showed an occasional positivity to S-100. This is the first case of such a tumor occurring in the gastrointestinal tract, and the findings suggest that gastric alveolar soft-part sarcomas may have a different origin from those arising in the skeleton.

Mucin-negative biopsy in extra-mammary Paget's disease. A diagnostic problem.

A case of extra-mammary Paget's disease with a mucin-negative small biopsy is reported. Study of a small series of vulvar Paget's disease demonstrated that areas devoid of mucin in the mm range are frequently found, creating the conditions for diagnostic problems in small biopsies. In this situation, positive immunoreactions for carcinoembryonic antigen and low molecular weight cytokeratins and a negative reaction for S-100 protein serves to differentiate Paget's disease from other pagetoid lesions.

Spinal synovial cyst (ganglion). Review and report of a case presenting as a retropharyngeal mass.

A synovial cyst (ganglion) of the anterior longitudinal ligament of the cervical spine, which presented as a retropharyngeal mass, is reported. Synovial cysts occur at various spinal sites and should always be included in the differential diagnosis of intraspinal extradural and paraspinal cysts.

Clear cell carcinoma arising in pleomorphic adenoma of the salivary gland.

Malignant change in pleomorphic adenoma of the salivary gland is not common. Clear cell carcinoma is an extremely rare form of malignant salivary gland tumor. A case of clear cell carcinoma of the submandibular gland arising in pleomorphic adenoma is reported.

Thymic carcinoma with focal neuroblastoma differentiation.

A small, incidentally found, thymic carcinoma (malignant thymoma) showed an extraordinary mixed-cell composition. The tumor was predominantly made up of poorly differentiated cells with light-microscopic, ultrastructural, and immunohistochemical features of thymic epithelium. However, small distinct groups of cells displaying features of neuroblastoma were scattered throughout the tumor. This unique case further illustrates the multiple capabilities of differentiation of thymic tumors.

Mixed crypt cell carcinoma. A clinicopathological study of the so-called 'goblet cell carcinoid'.

The clinicopathological features of six appendix and five bowel tumours with features of the so-called 'goblet cell carcinoid' are described. By light microscopy, these tumours were composed predominantly of mucous cells, together with variable proportions of endocrine and Paneth cells. Immunohistochemical and ultrastructural study confirmed this impression and no amphicrine cells were seen. The clinical course of all cases arising in the bowel, and three out of six appendix tumours was characterised by an aggressive behaviour with the development of widespread lymphatic and often intraperitoneal metastasis, but liver metastasis occurred in only one instance. We conclude, both from this study and from a review of the literature, that the 'mixed crypt cell carcinoma' forms a distinct clinicopathological entity justifying separate classification from adenocarcinoma and carcinoid tumour.

Artifactual changes mimicking signet ring cell carcinoma in transurethral prostatectomy specimens.

Histologic study of 20 consecutive cases of transurethral prostatectomy (TURP) showed aggregates of signet ring cells in the stroma in all but one case. They were usually associated with dense lymphocytic infiltrates, but occasionally they infiltrated the fibromuscular stroma and mimicked carcinoma. The absence of mucin and of immunoreactivity for prostate-specific acid phosphatase (PSAP) and prostate-specific antigen (PSA) and the focal positive immunoreaction for leukocyte common antigen (LCA) ruled out carcinoma and demonstrated the lymphocytic nature of some of the cells. Ultrastructurally, degenerated lymphocytes as well as vacuolated smooth cells were noted. None of the seven open prostatectomy specimens studied revealed this signet ring cell change. It is concluded that areas of chronic prostatitis in TURP specimens usually show degenerated lymphocytes and stromal cells with signet ring appearance that occasionally can mimic carcinoma. This is an artifact induced by the TURP procedure.

Primary amyloidosis of renal pelvis with duplicate collecting system.

A case of primary amyloidosis localized to the inferior renal pelvis of a kidney with a duplex collecting system is described. The onset of gross hematuria and mild flank pain necessitated investigations which yielded a clinical impression of tumor within the lower pelvis of a duplex collecting system. At laparotomy a grossly hemorrhagic-appearing mass in the lower pelvis was noted and a left ureteronephrectomy was undertaken. Histologic examination of the surgical specimen revealed amyloid deposition within the inferior pelvis, the corresponding distal portions of the papillae, and the most proximal ureter. Amyloid was not present elsewhere within either the renal parenchyma or the superior collecting system.

Secretory meningioma. A distinct subtype of meningioma.

Six meningiomas with abundant hyaline inclusions (pseudopsammoma bodies) were studied. As seen by light and electron microscopy, hyaline inclusions are composed of material of varying structures located in intracellular lumina lined by microvilli. A remarkable pericytic proliferation within the vessel walls was found in five cases. In all six cases, immunohistochemical examination for multiple antigens showed positive staining for carcinoembryonic antigen and epithelial membrane antigen in inclusions and surrounding cells. Weak positivity was found for keratin and secretory component in five cases and for alpha-1-antitrypsin and IgM in four cases. It is concluded that secretory meningioma is a distinct type of meningioma, usually meningothelial in type. It shows characteristic light-microscopic, ultrastructural, and immunohistochemical features of epithelial and secretory differentiation with accumulation of secretory material in the form of hyaline inclusions; marked vascular pericytic proliferation is also frequently present.