1/7. Sebaceous lymphadenocarcinoma of salivary glands.Primary sebaceous neoplasms of the salivary glands are extremely rare occurrences; furthermore, sebaceous lymphadenocarcinoma has only been reported in three patients. We report a case of sebaceous lymphadenocarcinoma arising in a lymphadenoma of the parotid gland. The patient was a 55-year-old man who presented with a parotid mass of 3 years' duration. Histologically, the lesion consisted of a sebaceous lymphadenoma with transition to a sebaceous carcinoma. The cytologic touch-preparation at the time of frozen section showed clusters of benign sebaceous cells in a rich lymphocytic background together with tridimensional clusters of malignant epithelial cells, strongly raising the suspicion of a malignant neoplasm arising in a benign sebaceous lesion. Malignant transformation of the sebaceous lymphadenoma, although rare, should be considered in enlarging, locally invasive parotid lesions, considering that clinical behavior and prognosis will be determined by the nature of the malignant component.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
2/7. Reactivity of monoclonal antibody OKM5 with sebaceous carcinoma.Two cases of sebaceous carcinoma (SC), as well as epithelial tumours, melanoma, and lymphoma, were examined using immunoperoxidase and a panel of monoclonal antibodies on cryostat sections. The results showed that, whereas all SC cells in both cases reacted strongly with monoclonal antibody OKM5, other tumour cells (except juvenile xanthogranuloma cells) did not. The pagetoid cells within the epidermis of SC also reacted with OKM5 antibody. Although the nature of the phenomenon merits further study, this reactivity, or cross-reactivity, might possibly aid diagnosis of SC.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
3/7. Abnormal division and gene expression in cultured cells from a patient with tuberous sclerosis.tuberous sclerosis is a dominant hereditary disease characterized by the appearance of angiofibromas on the face, epileptic attacks, and mental retardation. attention has been paid to the atypical cells observed histologically in the stroma of the angiofibroma as they may play an important role in forming lesions. We have established a cell line from an angiofibroma to clarify the nature of these cells at the cellular and biochemical levels. The cultured cells have been stably maintained for four years and show an abnormal morphology resembling that of neuronal cells. In culture, these cells divide into daughter cells, which consist of both normal cells and abnormal ones whose nuclei disintegrate and cannot divide further. The cells resemble normal fibroblasts in their pattern of staining with antibodies against tubulin, actin, vimentin, and fibronectin. However, they also stain with an antibody against the glia-specific acidic protein, which is thought to be a specific marker protein for glial cells. The gel profile of cyclic-AMP binding proteins was not fibroblastic, but rather of the neuron cell type. These results indicate the gene expression of these cells is also abnormal. They are a useful tool for understanding this specific genetic disease.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
4/7. Recurrent and residual sebaceous carcinoma after Mohs' excision of the primary lesion.We reviewed the histories of three patients with sebaceous carcinoma (two of the eyelid and one of the caruncle) who had had their tumors excised by surgeons experienced in the Mohs' technique. In each patient the tumor was considered totally excised. In one patient, residual intraepithelial pagetoid sebaceous carcinoma of the eyelid was detected incidentally when a reparative flap was placed. In the other two patients, invasive sebaceous carcinoma recurred, necessitating orbital exenteration; one patient has regional lymph node metastases. Because of the difficulty in detecting pagetoid spread on frozen sections and the multicentric nature of sebaceous carcinoma, we advocate managing these tumors by wide local excision, checking margins with high-quality permanent sections.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
5/7. Sebaceous carcinoma arising from bowen's disease of the vulva.Sebaceous neoplasms are a marker for malignancy in the muir-torre syndrome. bowen's disease has also been regarded by some as a cutaneous marker for various internal malignancies. An 89-year-old woman was noted to have a sebaceous carcinoma arising within a focus of vulvar bowen's disease. To our knowledge, this is the first known instance of such an occurrence. The finding of a sebaceous carcinoma in association with an atypical proliferation of keratinocytic, rather than basaloid, origin is unusual and is not accounted for in most classifications of sebaceous malignancy. This observation further supports the pluripotential nature of the cell line giving rise to both bowen's disease and sebaceous neoplasms.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
6/7. The masquerade syndrome.Malignant lesions of the lid and ocular adnexae may present with striking inflammatory signs and this has most often been described with meibomian gland carcinoma and given the name of the masquerade syndrome. This paper presents examples of lid malignancies which have not only masqueraded as predominantly inflammatory lesions but whose origin was further obscured by the nature of the spread of the tumour in lid and conjunctiva. Recognition of the true nature of the malignancy only follows biopsy of the centre of the lesion which is fully justified in an older patient presenting with unilateral chronic, unresponsive inflammation especially involving the canthus and bulbar conjunctiva as well as the lid. Histological confirmation of the nature of the peripheral spread of the tumour is also of importance since pagetoid spread has been shown to be associated with more aggressive neoplasia and increased mortality.- - - - - - - - - - ranking = 3keywords = nature (Clic here for more details about this article) |
7/7. Pigmented and nested sebomatricoma or seborrheic keratosis with sebaceous differentiation?Recently, the term sebomatricoma has been proposed as the most appropriate denomination to avoid controversial and confusing terms and to encompass all benign neoplasms with sebaceous differentiation. We report on two specimens that may be interpreted as examples of two new histopathologic patterns in sebomatricoma, namely, pigmented and nested sebomatricoma, or as seborrheic keratosis with sebaceous differentiation. The first case consisted of a neoplasm composed of basaloid immature cells with features of sebaceous differentiation in the form of clusters of sebocytes and sebaceous ducts, in addition to the proliferation of dendritic melanocytes arranged as solitary units scattered through the neoplastic aggregations of immature germinative sebaceous cells. The second case, in addition to the proliferation of single dendritic melanocytes as the first case, showed well-defined nests of basaloid and heavily pigmented germinative sebaceous cells connected to the skin surface and numerous sebaceous ducts. In the first case, the pigmented nature of the lesion was the most striking histopathologic characteristic, whereas the nested pattern was remarkable in the second one. Immunohistochemical investigations demonstrated positivity of cytokeratin MNF116 in neoplastic aggregations of germinative sebaceous cells, whereas the clusters of mature sebocytes and sebaceous ducts expressed epithelial membrane antigen positivity. S-100 protein made evident the scattered dendritic melanocytes, but neoplastic cells resulted negative.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |