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Biomedical subjects

N Weidner

Publications and source records attributed to N Weidner.

At least 127 records · Page 7Linked to original sources
PubMed1987

Cellular blue nevus simulating metastatic melanoma: report of an unusually large lesion associated with nevus-cell aggregates in regional lymph nodes.

A young Caucasian woman had a large area of blue-gray discoloration on the flank and palpable axillary lymph nodes. The discolored area had enlarged during a recent pregnancy, contained multiple subcutaneous nodules, demonstrated increased cellularity and mitotic activity, and was associated with an axillary lymph node containing black streaks within the capsule. Although the lesion was initially considered to be a metastatic malignant melanoma, re-evaluation showed it to be a benign cellular blue nevus with benign nevus-cell aggregates within a regional lymph node. We report this case to emphasize how cellular blue nevus can simulate malignant melanoma and to increase physician awareness of this benign variant of melanocytic nevus so that inappropriate surgery and chemotherapy can be avoided.

Adult↗
PubMed1987

Granuloma annulare: a rare occipital lesion in infants and children.

Subcutaneous granuloma annulare is a rare scalp lesion that occurs in infants and children. Occurrence in the occipital region, absence of bone involvement, slow growth, and foci of necrosis of collagen surrounded by palisading granulomatous inflammation are characteristic of this lesion. Although the cause remains unknown, it is not infectious and is more likely due to a defect in cell-mediated immunity. The prognosis after excision is excellent. Increased awareness that this peculiar granulomatous lesion can rarely occur in the soft tissue of the occipital region will help prevent confusion with neoplastic or infectious processes.

Granuloma↗
PubMed1987

Sarcomatoid carcinoma of the upper aerodigestive tract.

Sarcomatoid carcinomas are typically (but not always) biphasic tumors containing both carcinomatous and sarcomatous components. Within the upper aerodigestive tract, they arise from the mucosa and are predominantly composed of pleomorphic spindled cells associated with squamous carcinoma, the latter often presenting focally at the tumor base. Although their histogenesis is still debated, most authors favor metaplastic origin of the sarcomatous cells from carcinoma cells. Indeed, when studied with electron microscopy and/or immunohistochemistry the sarcomatous cells are frequently found to retain epithelial features; however, the sarcomatous metaplasia can be so complete that malignant cartilage, bone, and/or muscle cells are formed. In addition, metastatic deposits may contain sarcomatous and/or carcinomatous components. Sarcomatoid carcinomas are potentially aggressive tumors and should be treated accordingly. Although it is difficult to predict biologic behavior in every case, patients whose tumors are deeply invasive tend to have a poor prognosis, whereas those with superficially invasive tumors usually have an excellent prognosis.

Carcinoma↗
PubMed1987

Galactosemic nephropathy in the rat.

The effect of 30% galactose feeding on kidney function and structure was compared to the effect of streptozotocin-induced diabetes in the rat. In the galactose-fed rats there was increased urine volume (500%), creatinine clearance (40%), urinary albumin excretion (100%), urinary N-acetyl glucosaminidase (600%) and relative kidney weight (21%). These changes were similar to that observed in streptozotocin-induced diabetic animals. Galactitol in the kidney cortex of galactose-fed rats was increased 4 times similar to that observed for sorbitol in the streptozotocin-induced diabetic animals. Glycosylated hemoglobins were also increased in both galactose-fed animals and streptozotocin-treated animals. These data suggest that galactose feeding may be a useful model for investigating some aspects of diabetic nephropathy.

Acetylglucosaminidase↗
PubMed1986

Carcinosarcoma of the colon. Report of a unique case with light and immunohistochemical studies.

A unique case of carcinosarcoma of the colon is reported. The tumor invaded the bowel wall deeply, metastasized widely, resisted multi-agent chemotherapy, and caused the patient's death 4 years later. The tumor was composed of adenosquamous carcinoma admixed with sarcoma showing osseous, cartilaginous, and nonspecific spindle-cell differentiation. Although carcinoembryonic antigen appeared limited to carcinoma cells, cytokeratin immunoreactivity was observed in both carcinoma and sarcoma cells. Like carcinosarcomas at other body sites, the finding of cytokeratin in sarcoma cells supports partial epithelial differentiation in this component, likely retained from carcinoma precursor cells.

Aged↗
PubMed1986

Giant cell tumors of synovium (Pigmented villonodular synovitis) involving the vertebral column.

Giant cell tumors of synovium (pigmented villonodular synovitis) involving the vertebral column recently have been seen in two women: the third and fourth cases to be reported in the English-language literature. Unlike the previously reported cases, both these tumors grew outside the dura and produced symptoms of spinal cord compression. The first case involved lumbar vertebrae 5 and 6; the second, lumbar vertebrae 2 and 3. Even though initial resection of both tumors was incomplete, the patients improved postoperatively. One tumor was known to be unresectable at the time of surgery. In the other patient, a recurrence of symptoms required second and third resections 4 and 8 months after the first, respectively. Although synovial giant cell tumors rarely metastasize, the rate of local recurrence is high, especially if excision is incomplete. For this reason, close follow-up of patients with lesions in the spinal column is indicated. Increased physician awareness that synovial giant cell tumors can occur in the spine will help to ensure that these tumors are not misdiagnosed in this location.

Adult↗
PubMed1986

Three-dimensional studies of acellular glomerular basement membranes in dense-deposit disease.

After digestion removed the cells from glomeruli of frozen kidney tissue, we employed scanning electron microscopy to examine the acellular glomerular basement membranes (AGBM) from normal kidneys and from kidneys of patients with dense-deposit disease (DDD). The AGBM showed previously unrecognized three-dimensional patterns of pathologic changes. When compared to normal controls, the AGBM in DDD appeared "rigid" and thickened. Other pathologic features included coarsely granular or undulating epimembranous surfaces punctuated by single or clustered crater-like deformities. Although epimembranous crater-like deformities have been observed in other glomerulopathies, the combination of "rigid"-appearing AGBM punctuated by crater-like deformities is thus far unique to DDD.

Adolescent↗
PubMed1986

Scanning electron microscopy of the acellular glomerular and tubular basement membrane in lupus nephritis.

After using a cellular digestion technic to extract cells from the basement membranes of frozen kidney tissue, we used scanning electron microscopy to examine the acellular glomerular basement membranes (AGBM) and acellular tubular basement membranes (ATBM) from normal kidneys and from the kidneys of patients with lupus nephritis. This method revealed, in the AGBM, previously unrecognized three-dimensional patterns of pathologic changes. These patterns correlated with the World Health Organization (WHO) subclass of lupus nephritis and with the quantity of immune-complex deposition seen with two-dimensional microscopy. These pathologic changes included epimembranous, crater-like deformities with and without material resembling immune complexes; severely distorted, "moth-eaten" glomerular basement membrane; and the formation of secondary basement membrane within glomerular capillaries. We did not see similar abnormalities in the ATBM.

Adolescent↗
PubMed1986

Benign lymphoepithelial cysts of the parotid gland. A histologic, cytologic, and ultrastructural study.

Five cases of benign lymphoepithelial cysts (BLCs) of the parotid gland are reported, and the histologic, aspiration cytologic, and ultrastructural findings are described in detail. These uncommon parotid lesions contain epithelium-lined cystic spaces encased by abundant lymphoid tissue with germinal centers. The epithelium was "mucoepidermoid" in three of our cases and squamous in two. Familiarity with the morphologic features of BLCs should make it possible to distinguish them from similar-appearing cystic lesions, especially low-grade cystic mucoepidermoid carcinoma and cystic types of benign lymphoepithelial lesion (so-called Mikulicz's disease). These distinctions, however, are difficult on aspiration cytology specimens.

Adult↗
PubMed1986

Aspiration cytology of salivary glands.

Although mass lesions of the salivary glands are readily accessible to examination by fine-needle aspiration, the use of this modality has been limited. In part, this may be related to the difficulty differentiating between benign and malignant neoplasms in some cytologic specimens. Marked atypia in reactive non-neoplastic epithelium also could result in a false-positive diagnosis. In addition, aspiration of hypocellular material from cystic neoplasms, eg, well-differentiated mucoepidermoid carcinoma, may lead to false-negative cytologic reports. However, the diagnostic specificities claimed by a number of authors for this method are excellent. Furthermore, aspirates of certain specific neoplasms may yield highly distinctive cellular samples, such as the uniform tumor cells and extracellular hyaline spheres in many adenoid cystic carcinomas. Another example is the characteristic transition between the epithelial and myoepithelial cells of pleomorphic adenomas, which may contain prominent myxoid matrical material. With the increasing recognition of such features, the reported levels of diagnostic accuracy are improving.

Adenoma, Pleomorphic↗
PubMed1986

Scanning electron microscopy of the acellular glomerular basement membranes in idiopathic membranous glomerulopathy.

After using a cellular digestion technique to extract cells from the basement membranes of frozen kidney tissue, we employed scanning electron microscopy to examine the acellular glomerular basement membranes (AGBM) from normal kidneys and from kidneys of patients with idiopathic membranous glomerulopathy (MGN). This method revealed, in the AGBM, previously unrecognized three-dimensional patterns of pathologic changes. These patterns correlated with increasing MGN stage as defined by Ehrenreich and Churg. On the epimembranous AGBM surface these patterns were composed of ridge-like trabeculae, irregular plaques, and reticulated crater-like deformities. The endothelial AGBM surfaces were smooth in stages I and II MGN, but in stage III MGN the endothelial surfaces were irregular and perforated. In contrast to lupus-related MGN, where some immune-complex-like material remained after cellular extraction, epimembranous immune-complex-like material in idiopathic MGN was extracted.

Adult↗
PubMed1985

Neoplastic pathology of oncogenic osteomalacia/rickets.

Reported are two cases of oncogenic osteomalacia, each caused by a small mesenchymal tumor, with detailed assessment of the tumors by light microscopy, electron microscopy, and immunohistochemistry. One tumor was a primitive mesenchymal tumor with prominent giant cell and vascular components, and the second resembled the giant cell variant of soft parts chondroma. Osteoclast-like, multinucleated giant cells and vascularity were prominent features in both tumors. Although the literature documents a histologically heterogeneous group of tumors as causing this syndrome, most have multinucleated giant cells and/or extensive vascularity. The high incidence of these two histologic features in this group of tumors suggests that either or both may be related to the pathogenesis and/or metabolic consequences of oncogenic osteomalacia/rickets.

Adult↗
PubMed1985

Epidermotropic metastatic squamous cell carcinoma. Report of two cases showing histologic continuity between epidermis and metastasis.

Two unusual cases of squamous cell carcinoma (SCCa) metastatic to skin from distant sites occurred. In both metastatic sites, the malignant squamous epithelium fused with benign surface epithelium, and the resulting transition simulated that typically seen in primary cutaneous SCCa. We believe that this previously unreported phenomenon is an expression of the natural tendency of squamous epithelium to "heal" denuded connective tissue surfaces by proliferation followed by epithelial fusion. Because epithelial continuity can be established between benign keratinocytes and metastatic SCCa, one cannot rely on this single morphologic finding to separate primary from metastatic disease.

Aged↗
PubMed1985

Oncogenic osteomalacia: strange tumours in strange places.

Two patients presented with hypophosphataemic osteomalacia and were subsequently found to have small tumours unusual histopathology and location causing the osteomalacia. Each tumour was found after an intensive search for occult masses. Studies of vitamin D metabolism and renal tubular function before and after surgery yielded further insight into the pathophysiology of oncogenic osteomalacia. These cases demonstrate that microscopic quantities of tumour are capable of causing the syndrome and further illustrate the high index of suspicion often necessary to locate causative tumours in patients with hypophosphataemic osteomalacia.

Adult↗
PubMed1985

Adenosquamous carcinoma of the skin. An aggressive mucin- and gland-forming squamous carcinoma.

Two cases of an aggressive cutaneous carcinoma showed both squamous and adenomatous differentiation. These neoplasms invaded subcutaneous structures with a sclerosing pattern, making surgical resection difficult. Unlike the usual squamous carcinoma, glands and epithelial mucin (sialomucin) were produced. This mucin stained with mucicarmine and was sensitive to sialidase and resistant to hyaluronidase digestion. No mucin with similar histochemical properties was found in a study of 50 consecutive cutaneous squamous carcinomas and 50 consecutive basal cell epitheliomas from our files. Literature reports of histologically similar cutaneous carcinomas together with our experience with these two cases suggest aggressive behavior for this category of neoplasm.

Adenocarcinoma↗
PubMed1985

Neurosarcomatous malignant melanoma arising in a neuroid giant congenital melanocytic nevus.

We report a case of neuroid giant congenital melanocytic nevus (GCMN) in which a malignant schwannomalike tumor developed. Literature review reveals that neurosarcomatous differentiation occurs among malignant tumors arising in GCMNs, apparently with greater incidence in those GCMNs showing benign neuroid differentiation. Although the differences between neuroid melanocytes and Schwann's cells may be more conceptual than real, we believe that the current tumor arising within a melanocytic nevus is likely of neuroid melanocytic origin and best designated as neurosarcomatous malignant melanoma.

Humans↗
PubMed1984

Sulfasalazine in treatment of collagenous colitis. Case report and review of the literature.

A patient is described with chronic colitis, watery diarrhea, and colonic mucosal subepithelial collagen deposition that resolved while being treated with sulfasalazine. The clinicopathologic features were consistent with collagenous colitis. Theoretically, the thickened collagen layer impairs water and electrolyte absorption, producing watery diarrhea. Such increased collagen is rarely observed in other inflammatory colon diseases and may represent a distinct morphologic reaction to various, yet undefined, injuries. Although the clinical course is benign, appropriate therapy for the debilitating symptoms is poorly understood. This report suggests that sulfasalazine may be helpful in some cases.

Chronic Disease↗