Spinal intradural ependymal cyst: a case report and review of the literature.

Spinal intradural ependymal cysts are extremely rare. The case presented is the sixth reported in the literature. The symptoms are consistent clinically and radiologically with a spinal intradural space-occupying lesion. The cyst wall is lined with both ciliated and nonciliated cells, resting directly on connective tissue. The exact embryonal origin of these cysts is obscure.

Stimulation of bone formation by electrical current on spinal fusion.

An experimental double-blind study to evaluate the effectiveness of a constant current stimulator was performed on 30 young pigs that underwent a spinal fusion at the level of L5-L6. The group of animals with an active bone-growth stimulator showed a statistically significant increase of osteoblastic activity with bone formation.

Angioimmunoblastic lymphadenopathy following Kaposi's sarcoma.

The close relationship of Kaposi's sarcoma (KS) with other lymphoproliferative disorders is a poorly understood, but well documented, phenomenon. A case is presented of a 68-year-old woman with the classical form of cutaneous KS in whom disappearance of the lesions after treatment was shortly followed by the development of angioimmunoblastic lymphadenopathy, pursuing a fulminant course to death. Postmortem examination revealed diffuse involvement of the marrow, spleen, liver, and lymph nodes by the immunoblastic proliferation. The close association of these two conditions may represent more than a chance occurrence. The appearance of a constellation of nonspecific symptoms suggestive of a lymphoproliferative disorder in debilitated patients with KS should alert the physician to the possibility of the development of this rare complication.

Fibrosarcoma of the urinary bladder. Study of a case showing extensive chondroid differentiation.

A case of primary fibrosarcoma of the urinary bladder showing extensive chondroid differentiation was studied by light microscopy and immunofluorescent microscopy using tissue-specific antibodies against intermediate filaments. The tumor cells were uniformly and positively labeled with vimentin antibodies and were negative for desmin and keratin, thus confirming the nonmuscle mesenchymal origin of the neoplasm. The value of intermediate filament typing in the differential diagnosis of spindle cell tumors of the urinary bladder is discussed, and a review of the literature on the subject is presented. It is postulated that the retained capacity for continued differentiation displayed by this tumor may account for the relatively better prognosis observed for this patient.

Hemisplenectomy using a hand-held CO2 laser. An experimental study.

Hemisplenectomy was performed in mongrel dogs using a hand held CO2 laser. Cutting and hemostasis were performed by a laser beam with a high concentration power--about 6kW/mm2--at the focal spot, and residual bleeding was controlled by using a defocused beam. The cutting action was improved by temporary closing of the arterial vessels and by injecting adrenaline into the splenic artery to produce a relatively dry surface. The surgical procedure was free of mortality or morbidity. Histological studies revealed a brand of fibrous tissue at the cut surface, without apparent abnormalities in the splenic parenchyma beneath the section. Activity of the residual half spleen was shown by postoperative technetium scan and by the fact that Howell-Jolly bodies appeared in peripheral blood only after resection of the remaining half spleen.

Imprint cytology in the intraoperative diagnosis of malignant melanoma.

Imprints were prepared from 73 pigmented skin lesions, 19 of which were diagnosed as malignant melanoma. The cytologic findings in malignant melanoma, large clusters of cells with loss of cellular cohesiveness and large pleomorphic nuclei, were positive in 17 of the 19 cases. In other malignant and benign pigmented lesions the few cells adherent to the glass showed characteristic cytologic features of the particular lesion. Imprint cytology seems to be a valuable adjunct to the examination of frozen sections for the intraoperative diagnosis of malignant melanoma.

Post-traumatic reactive and resorptive lesions of the medial end of the clavicle.

Three soldiers presented with a painful swelling of the sternoclavicular area. Computed tomography (CT) studies showed sclerosis as well as lysis of the medial end of the clavicle with adjacent soft-tissue swelling. Bone biopsy revealed new bone formation and inflammatory reaction; cultures were negative, no tumor cells were found. The patients recovered after antibiotic treatment. Although the CT findings cannot completely rule out a malignant lesion, these changes in the medial end of the clavicle in young people may suggest trauma as the etiology.

Acinic cell tumor of the bronchus.

A bronchogenic tumor was removed from a 12-year-old girl. Histology showed a clear cell lesion with electron microscope features compatible with serous acinic cell origin.

Myeloid bodies formation in triparanol treated cultured cells.

Cultured cells (chicken embryo liver cells and rat embryo fibroblasts) were treated with triparanol (MER-29) for various lengths of time. Both types of cells have developed numerous membranous whorls-myeloid bodies in the cytoplasm. Various stages in myeloid bodies development are described. Acid phosphatase activity was cytochemically demonstrated within the myeloid bodies, indicating their lysosmal nature. This activity appeared only at a late stage of the myeloid bodies formation.

Oxidation of lipids and membranes II: Effects of oxidants on cerebral white matter homogenates.

Bovine cerebral white matter homogenates were oxidized by various oxidizing solutions of equal molarity and subsequently extracted with water. Most of the oxidants tested (K-dichromate, FeCL3, H2O2, O2, and chloroperbenzoic, ascorbic, performic, and periodic acids) rendered the various myelin constituents less extractable than the constituents of unoxidized control homogenates. KMnO4, and to a lesser degree hemoglobin, rendered myelin constituents more extractable with water than those of the control homogenates. The findings indicate that most of the oxidants produced stabilization of the lamellar pattern, probably through cross-linking and polymerization. KMnO4 and hemoglobin caused labilization and breakdown of the membranous structure. Proof that stabilization of membranes is caused by some oxidants and that fragmentation occurs by the action of KMnO4 and hemoglobin was obtained by the light scattering technique and by electron microscopy of the oxidized homogenates. Evidence obtained indicated that formation of hydrophobic end groups during oxidation favors polymerization, while prevalence of hydrophilic groups is associated with fragmentation.

Verrucous pseudonevoid melanoma.

A case of an unusual variant of malignant melanoma resembling a papillomatous dermal nevus is presented here. The lesion was initially diagnosed as a Spitz nevus, and recurred locally five months after excision. The features which distinguish this lesion from the more common types of benign dermal nevi include the architectural atypia of the melanocytes, with a tendency for continuous proliferation of single cells along the dermoepidermal junction, as well as the presence of cytologic atypia with large hyperchromatic nuclei and mitoses. Despite its seemingly innocent appearance, distinction of this low-grade variant of melanoma from its benign counterparts is of importance in order to avert the possibility of recurrence and potential metastases.

Paget's disease of the breast with underlying carcinoma arising in systemic scleroderma.

A case is presented of Paget's disease of the breast with underlying infiltrating carcinoma arising in a 35-year-old woman with systemic scleroderma. The tumor arose in an area of the skin affected by the systemic scleroderma 4 years after the onset of her systemic disease. The possibility of a causal relationship between these two processes is discussed and a brief review of the literature is presented.

Adenosquamous carcinoma of the gallbladder with spindle cell features. A light microscopic and immunocytochemical study of a case.

A case of adenosquamous carcinoma of the gallbladder showing extensive spindle transformation is presented. By light microscopy, areas showing interwoven fascicles of fusiform, poorly differentiated cells closely resembling a sarcoma were seen to merge imperceptibly with areas showing more obvious glandular and squamous cell features. Immunocytochemistry utilizing tissue-specific antibodies against intermediate filaments demonstrated the exclusive presence of prekeratin antibodies in both components of the tumour, thus establishing the epithelial nature of this neoplasm. The importance of immunological phenotyping in the differential diagnosis of epithelial tumours of the gallbladder showing pseudosarcomatous features is underscored.

Pitfalls in frozen section diagnosis of malignant melanoma.

The importance of obtaining an intraoperative diagnosis and measurement of thickness of a malignant melanoma has emerged since the change in the surgical approach towards thin melanomas (0.75 mm). In experienced centers, both diagnosis and thickness, can be established on frozen section. Eighty-four pigmented lesions were examined on frozen section. Thirty of 31 were correctly diagnosed as malignant melanomas. The one not diagnosed was a regressing melanoma. The frozen section diagnosis of a regressing melanoma is difficult, and this should be deferred until paraffin sections are examined. In 29 consecutive skin melanomas thickness was measured on frozen section and was found to be 0.1-0.4 mm more than that measured on paraffin sections of the same specimens. It is therefore suggested that tumors measuring up to 0.85 mm on frozen section should be included in the group of thin melanoma.