1/1149. Epithelioid cell histiocytoma: a simulant of vascular and melanocytic neoplasms.Epithelioid cell histiocytoma (ECH) is an unusual and still poorly recognized variant of benign fibrous histiocytoma. Epithelioid cell histiocytoma differs from most benign fibrous histiocytomas in five important ways: the predominance of epithelioid cells, relative lack of secondary elements (such as giant cells, foamy, or hemosiderin-laden macrophages), relative sharp circumscription, prominent vascularity, and centering in the papillary dermis in most cases. A strong resemblance to melanocytic and vascular lesions has been noted, and a recent case was reported with features suggesting endothelial origin. Fifteen new cases of ECH, including one example of the rare deep cellular variant, are presented herein, with emphasis on features mimicking vascular and melanocytic neoplasms. Labeling with endothelial markers, including previously unreported CD-31 labeling, showed abundant vascular staining, which may be challenging to interpret, but which does not indicate an endothelial origin of ECH.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
2/1149. Apocrine poroma: a distinctive case in a patient with nevoid basal cell carcinoma syndrome.Traditionally, poromas have been classified as eccrine neoplasms, but several recent reports of poroid tumors with sebaceous, follicular, and apocrine differentiation have challenged this idea. In support of alternative differentiation, a case of an "apocrine" poroma is reported in a 19-year-old man with the nevoid basal cell carcinoma syndrome. A papule on the right cheek, thought clinically to be a basal cell carcinoma, was excised. Anastomosing lobules of small uniform basaloid (poroid) cells formed small ductular structures lined by eosinophilic cuticles and extended into the superficial reticular dermis. The neoplasm originated from follicular infundibula and was surrounded by a myxoid stroma. Focally, primitive hair bulb and papillae differentiation was present, and some of the ducts were lined by cells suggesting decapitation secretion. The histologic pattern and the common embryologic origin of the folliculosebaceous-apocrine unit support apocrine differentiation of this tumor. The association with the nevoid basal carcinoma syndrome appears to be unique. This case, in addition, demonstrates overlapping features with the infundibulocystic type of basal cell carcinoma commonly seen in the basal cell nevus syndrome.- - - - - - - - - - ranking = 0.4keywords = neoplasm (Clic here for more details about this article) |
3/1149. Basal cell carcinoma with massive ossification.We report a case of basal cell carcinoma with massive ossification in a 66-year-old white man. Ossification in various benign and malignant neoplasms have been reported including basal cell carcinomas, in which ossifications are seen in small foci or peripheral rim of the tumor. However, in our case, massive ossification is seen throughout the tumor, and only small areas of the periphery of the tumor show diagnostic histology. Therefore, this case might have presented a diagnostic difficulty or been misdiagnosed as an osteoma cutis if a smaller incisional or punch biopsy had been performed. The phenomenon of bone formation itself is not specific for any diagnostic entity, and therefore an underlying lesion should be carefully sought in case of secondary ossification.- - - - - - - - - - ranking = 0.2keywords = neoplasm (Clic here for more details about this article) |
4/1149. adenocarcinoma with signet ring cells of the axilla showing apocrine features: a case report.A 74-year-old Japanese man developed a reddish, indurated plaque composed of multiple nodules on his right axilla. Histopathologic examination showed a solid tumor that extended from the upper dermis into the subcutis, with both inter- and intracellular lumen formation, cellular arrangement in single files, a fibrotic reaction around the tumor cells, and the presence of mucinous material in the cytoplasm. There was both nuclear and cytoplasmic pleomorphism. Both lysozyme and GCDFP-15 were identified in the tumor cells. Electron microscopic examination showed periluminal condensation of the cytoplasm. Because thorough clinical and laboratory examinations were unremarkable, we regarded this to be a case of primary adenocarcinoma with signet ring cells of the axilla. The neoplasm might have differentiated toward the apocrine sweat glands or the mammary glands. radiation therapy was effective to some degree. This seems to be the first reported case in which adenocarcinoma with signet ring cells of the skin affected a site other than the eyelids.- - - - - - - - - - ranking = 0.2keywords = neoplasm (Clic here for more details about this article) |
5/1149. Unusually differentiating immature nerve sheath myxoma in association with dermal melanocytosis.A 44-year-old woman presented with a slightly elevated, erythematous lesion, with partially blue-black areas. The nonpigmented area histologically showed a "dissecting" fascicular growth pattern, similar to one of the patterns seen in the cellular type of nerve sheath myxoma. The clinically pigmented part of the lesion consisted of diffusely infiltrating, broad and poorly delineated fascicles often showing nerve sheath differentiation, embedded in a highly myxomatous stroma. No part of the lesion showed the plexiform pattern typical of the classic type of nerve sheath myxoma; rather, the lesion had some common features of neurofibroma, and also was characteristically associated with a considerable number of scattered dermal melanocytes. However, based on the fascicular histologic pattern showing nerve sheath differentiation within mucinous matrix, S-100 protein-negative immunophenotype, and electron microscopic features, we considered the whole lesion in the present case to be an entity within the spectrum of nerve sheath myxoma, either mixed-type nerve sheath myxoma or unusually differentiating immature nerve sheath myxoma, except for the associated dermal melanocytosis. Because of the intimate association of the dermal melanocytes with this nerve sheath myxoma with divergent differentiation, this lesion can also be considered as a distinctive type of benign neoplasm derived from pluripotent neural crest cells.- - - - - - - - - - ranking = 0.2keywords = neoplasm (Clic here for more details about this article) |
6/1149. Treatment of complicated cutaneous malignant neoplasms by modern radiotherapy: principles, practice, and results.The indispensability of modern radiotherapy for certain complicated cases of cutaneous malignant neoplasms is demonstrated by a review of its principles and demonstration of results achieved by its practice in five representative cases.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
7/1149. Papillary formations in metastatic melanoma.Cytomorphologic features of melanoma can be extremely variable, in that they can mimic other poorly differentiated neoplasms. Ten cases of metastatic melanoma with distinct, cohesive, papillary tissue fragments observed in fine-needle aspiration (FNA) specimens are reported. These papillary fragments exhibited a central fibrovascular core with attached tumor cells, in a background of single scattered malignant cells, macrophages, and focal necrosis. The aspiration sites included regional or distant palpable lymph nodes, pancreas, bone, and skin. Nine cases had a histologic diagnosis of primary cutaneous melanoma, and in one case the primary skin tumor was detected after the diagnosis was established by FNA of the metastasis. Immunohistochemical studies (S-100 protein, HMB-45 antigen, and factor viii) were performed in four cases, and electron microscopy in one, confirming the diagnosis of melanoma. An awareness of this cytomorphologic variation of papillary formations in cytology preparations from metastatic melanoma is important and can prevent potential inaccurate interpretation.- - - - - - - - - - ranking = 0.2keywords = neoplasm (Clic here for more details about this article) |
8/1149. birt-hogg-dube syndrome and Hornstein-Knickenberg syndrome are the same. Different sectioning technique as the cause of different histology.The autosomal dominant inherited syndromes of Hornstein and Knickenberg (HKS), and Birt, Hogg and Dube (BHDS) are both characterized clinically by the overall spread of multiple flesh coloured papules of the skin. However, it is a matter of debate if colonic neoplasms (adenomas as well as adenocarcinomas) are associated findings in the HKS or rather in the BHDS. Furthermore, histological differences are said to exist between the skin lesions in the two syndromes: whereas perifollicular fibromas were described in the HKS, fibrofolliculomas and trichodiscomas were found in the BHDS. In the present study, we report on a father and his daughter in whom we initially diagnosed a BHDS. We then examined a greater number of the papular lesions in histologic sections cut vertically as well as horizontally to the epidermis. Our results indicate that the histologic differences between the skin lesions in the two syndromes are artificial ones, caused by interpretation of different sectioning planes, and that consequently HKS and BHDS are the same. Therefore, it is necessary to look for colonic polyps in the syndrome in question, regardless if one prefers the name HKS or BHDS for it.- - - - - - - - - - ranking = 0.2keywords = neoplasm (Clic here for more details about this article) |
9/1149. Unusual presentation of a salivary pleomorphic adenoma: a case report and review of the literature.Although pleomorphic adenomas are the most common neoplasms of salivary gland origin, our knowledge of the etiology, growth, and recurrence patterns, and significance of the varying histologic features of these tumors, remains limited. We present the case of a 66-year-old man with an unusual presentation of a pleomorphic adenoma, and review the important clinical and pathologic features of this entity.- - - - - - - - - - ranking = 0.2keywords = neoplasm (Clic here for more details about this article) |
10/1149. Metastatic testicular teratoma of the nasal cavity: a rare cause of severe intractable epistaxis.Malignant neoplasms of the nasal cavity and paranasal sinuses are uncommon. choriocarcinoma is a highly malignant germ cell tumour occurring in the reproductive organs. Metastasis may be principally by the lymphatic route as in other germ cell tumours but choriocarcinoma is also known to spread haematogenously. We present a rare case of metastatic choriocarcinoma to the nasal cavity from testicular teratoma presenting with intractable epistaxis in a 32-year-old Caucasian male, who ultimately succumbed to this disease.- - - - - - - - - - ranking = 0.2keywords = neoplasm (Clic here for more details about this article) |
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