Primary malignant melanomas of the lung and adrenal.

Malignant melanoma originating outside the skin, juxtacutaneous mucous membranes, eyes, and leptomeninges is a very rare neoplasm. Two such primary visceral malignant melanomas from the lung and adrenal are described in detail.

Malignant fibrillo-caveolated cell carcinoma of the human intestinal tract.

The ultrastructural features of a peculiar midgut carcinoid, containing cytoplasmic filaments, fibrils, and caveolae, are presented. Because of the morphologic similarities between the tumor cells and the recently described intestinal caveolated cell, it is proposed that the cells of the reported carcinoid represent the malignant counterpart of this new type of cell. The name suggested for this variant of a tumor of the enterochromaffin group of intestinal endocrine cells is malignant fibrillocaveolated cell carcinoma.

Polyploidy in islets of normal and diabetic humans.

This study was designed as a pilot project to determine whether the increased polyploidization of pancreatic B cells in diabetic mice reported from our laboratory is also characteristic of human diabetes. Nuclei of hematoxylin and eosin stained islets cells were traced by camera lucida and their volumes determined by semiautomatic particle size analysis. Previous studies have confirmed that nuclear volume can be used as an index of polyploidy, since, in mouse and human islets, the nuclear DNA content is directly proportional to the nuclear volume. Five insulin independent and three insulin dependent human diabetic patients and their age and sex matched controls were studied. The percentages of polyploid nuclei in insulin independent diabetic islets were elevated significantly over those in control subjects in four of five cases; the exception was an 85 year old male who was diagnosed as a diabetic only two months prior to death. Of the three insulin dependent diabetics, one, whose islets appeared otherwise normal, had a significantly greater percentage of polyploid nuclei than the controls; the other two, whose islets were markedly hyalinized, exhibited percentages of polyploid nuclei within normal ranges. The implications of relative percentages of polyploid nuclei in normal and diabetic islets and the possible relationship with previous studies of genetically diabetic mice are discussed.

Tubular carcinoma of the breast. A study of frequency.

Tubular carcinoma of the breast is a recognizable histologic type of invasive mammary carcinoma, characterized by infrequent axillary lymph nodal metastases and an excellent prognosis. Of all carcinomas of the breast diagnosed in 1974 in the Louisville area, 42, or 10.3% were of the tubular variety. This is in contrast to the previously expressed opinion that tubular carcinoma is rare. Three histologic types of tubular carcinoma are described. Strict criteria for diagnosis of the mixed type are recommended.

Renal amyloidosis associated with systemic lupus erythematosus.

A renal biopsy of a patient who had systemic lupus erythematosus and proteinuria revealed the presence of both amyloidosis and lupus glomerulonephropathy. The association between secondary amyloidosis and systemic lupus erythematosus has only been reported in four previous cases. The significance of this association is discussed.

An islet of Langerhans located within the epithelium of a human pancreatic duct.

An unusual structure resembling an islet of Langerhans was described in the pancreatic ductal epithelium of a presumably normal human male. Further studies to establish the identities of both islet and duct were performed. The original hematoxylin and eosin section served for histological description, as well as for nuclear volume analysis to characterize levels of beta cell polyploidy. The section was restained with Gomori's Chrome Alum Hematoxylin Phloxine to ascertain the presence of islet-like cells and to quantitate the ratio of beta- to non-beta cells. The section was then restained by the Feulgen technique to confirm proportionality between nuclear volume and DNA content. An apparently normal islet in the same section served as control. The combined observations were consistent with the interpretation that the structure is indeed an islet situated within the ductal epithelium. The almost complete absence of polyploid beta cells, however, and the high ratio of non-beta cells:beta cells suggested that it was a young islet. A similarly high proportion of non-beta cells in the control islet, as well as the frequent occurrence of ducts within, or in close proximity to, other islets, suggested that the entire islet organ was under some form of proliferative stimulus at time of resection. Alterations of the ductal epithelium and the secretory contents suggested that the duct was also in the process of transformation. Although the islet had apparently arisen within the ductal epithelium, the ultimate source of the progenitor cells could not be determined from these studies. The relationship of the ductal islet to other well known forms of islet regeneration is discussed.

Spinal gliosarcoma: a light, immunohistochemical and ultrastructural study.

Gliosarcomas are mixed tumors of the brain containing both malignant neuroectodermal and mesenchymal components. Over 100 cases have been reported within the brain; however, to our knowledge, this is the first reported case located primarily within the spinal cord. Along with a review of the literature, the light, immunohistochemical and ultrastructural findings of a spinal gliosarcoma are reported in a 41-year-old woman with a previously diagnosed oligodendroglioma of the cerebellum 15 years earlier and a concurrent pituitary adenoma. The spinal tumor appears to be morphologically identical to its intracranial counterpart.

Morphological changes in Trypanosoma brucei rhodesiense following inhibition of polyamine biosynthesis in vivo.

The effect of alpha-difluoromethylornithine (DFMO) treatment on the morphology of African trypanosomes was investigated. For this purpose inbred mice were immunosuppressed and infected with a clone of the protozoan blood parasite Trypanosoma brucei rhodesiense. The mice were then treated with DFMO, an irreversible inhibitor of ornithine decarboxylase, which inhibits polyamine synthesis. DFMO treatment in the absence of host immunity resulted in arrest of cytokinesis of the trypanosomes and many binucleated cells could be seen in blood smears. If mice were infected with a highly virulent trypanosome clone (ETat 1.10), which does not normally transform from long slender (LS) to short stumpy (SS) forms, DFMO treatment caused SS transformation to occur on days 3-4. This morphological SS transformation was substantiated by the presence of diaphorase activity and nuclear and mitochondrial changes. The results suggest a possible involvement of polyamines in the transformation from LS to SS forms.

Crystalline deposits in ascites in a case of cryoglobulinemia.

Crystalline inclusions were observed on routine cytologic studies of ascitic fluid from a patient with exudative ascites of undetermined cause. These inclusions were polymorphic, but frequently appeared as slender needles. They were seen most often in histiocytes and, less frequently, in mesothelial cells and plasma cells. Extracellular crystals were also seen. The crystals were also present in biopsy specimens of peritoneum, liver and bone marrow. Special studies by polarizing light microscopy, cytochemistry, electron microscopy and immunocytochemistry suggested that the crystals were most probably immunoglobulins synthesized by plasma cells. Some were excreted extracellularly and phagocytized by histiocytes. Further studies indicated that the patient had an indolent plasma-cell dyscrasia, resulting in excessive production of a monoclonal immunoglobulin. The immunoglobulin may have crystallized and become deposited in tissues, inciting chronic inflammatory changes. Massive deposits of crystals in the peritoneum, with the resultant inflammatory reaction, was possibly the cause of the formation of ascites.

Retroperitoneal sarcoma with features suggestive of alveolar soft part sarcoma.

A 72-year-old man presented with a 15 x 12 x 5 cm cystic and necrotic tumor involving the superior region of the stomach and the retroperitoneum down to the transverse colon and extending laterally from the left lobe of the liver to the spleen without involving either organ. Light microscopy showed the tumor cells to be arranged in an organoid pattern. Immunocytochemistry showed a strong reaction for desmin and vimentin. Electron microscopy demonstrated features suggestive of an alveolar soft part sarcoma.

Chordoid tumor: a light, electron microscopic, and immunohistochemical study.

Chordoid tumor--synonymous with chordoid sarcoma, parachordoma, and peripheral chordoma--is a very rare neoplasm with histologic similarity to chordoma that is found outside the axial skeleton. A soft tissue chordoid tumor in the gluteus maximus muscle of a 42-year-old man is presented. This tumor had morphologic features identical to a chordoma: nodular growth with vacuolated cytoplasm and myxomatous stroma by light microscopy, positive immunoreaction for cytokeratin and epithelial membrane antigen by immunohistochemistry, desmosomes, intercellular lumina lined with microvilli, and the presence of basal lamina material by electron microscopy. Two similar cases have been reported in the English literature.

Contact between abluminal microvilli and collagen fibrils in metastatic adenocarcinoma and mesothelioma.

It can be difficult to differentiate between epithelial and mixed type mesothelioma and metastatic adenocarcinoma. To distinguish between the two, it has recently been suggested that the presence of abluminal microvilli making contact with collagen fibrils through discontinuities in the basal lamina was characteristic of mesothelioma but not of metastatic adenocarcinoma. This study presents three patients out of 39 who had adenocarcinoma metastatic to the pleural and abdominal cavities, in which direct contact was observed between abluminal microvilli and collagen fibrils. All 39 examples of mesothelioma which were also examined demonstrated this feature. This phenomenon should therefore not be used as a discriminator between mesothelioma and metastatic adenocarcinoma. An additional patient with metastatic adenocarcinoma in an axillary lymph node demonstrates that this phenomenon is not limited to the pleural or abdominal cavities.