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101.
We report a case of metastatic lobular breast carcinoma with extrahepatic gastrointestinal disease. On the basis of clinical findings, radiologic investigations, computerized axial tomography, gastrointestinal endoscopy, and gastric biopsy, the diagnosis of gastric and ileal Crohn's disease was made. The correct diagnosis of peritoneal carcinomatosis was made at laparoscopy. This case exemplifies the utility of laparoscopy in establishing the diagnosis and staging for abdominal disease of uncertain etiology.  相似文献   
102.
Primary squamous cell carcinoma of the submandibular gland is a rare tumor. In this report, the histological and ultrastructural features of a case of primary squamous cell carcinoma arising in the left submandibular gland is presented. Light microscopically, the tumor consisted of well differentiated keratinizing squamous cell nests. Ultrastructurally, the tumor cells were oval or spindle-shaped, and several tumor cells had intracytoplasmic desmosome-like structures, resembling intercellular desmosomes. The majority of the tumor cells contained a large number of intermediate filaments (tonofilaments). Intercellular desmosomes were well developed. No secretory granules were found. These ultrastructural features may enable us to distinguish primary squamous cell carcinoma from mucoepidermoid carcinoma which is often misdiagnosed as squamous cell carcinoma.  相似文献   
103.
Secretory (so-called juvenile) carcinoma of the breast, first described in children, occurs also in adult women, predominantly in the third decade. Less commonly it is seen in older age groups, up to the eighth decade. We report five patients with this tumour; one, a female aged 73, is the oldest age at which the tumour has been recorded, and one is the first report in an adult male in whom the disease recurred after 20 years, only the second recorded death attributable to this tumour type. Secretory carcinoma in adults is potentially more aggressive than in childhood. Nodal metastases are more frequent and sometimes more extensive. Recurrence of tumour after surgery developed in four of our five patients at 3, 8, 15 and 20 years. Slow growth and delayed recurrence are characteristic of many of these tumours. Death from systemic metastases is rare, but may ensue either rapidly or following a long latent period after treatment. Prolonged follow-up is needed to assess accurately the biological behaviour of this tumour.  相似文献   
104.
Summary Most series in Africa show a high percentage of hepatitis B surface Hepatitis antigen in hepatocellular carcinoma. Two groups of cases were investigated in this study. The one was derived from the autopsy material at Baragwanath hospital from subjects who had lived in Soweto, a large Black urban town. The second group consisted of male Black mineworkers generally originating from rural areas. A combination of the aldehydefuchsin stain and immunoperoxidase technique was used. The two groups showed totally different results. The Baragwanath series consisted of 24 hepatocellular carcinomas of which only 4 (17%) were HBsAg positive. Of the 24 cases, 14 had cirrhosis of which 9 were macronodular and 5 micronodular. Ten of these cases showed heavy iron overload. The series of male Black mineworkers comprised 22 cases of which 16 (72%) were HBsAg positive. Twelve of the 22 cases showed a macronodular cirrhosis and there were no micronodular cirrhoses. Only one case showed severe iron overload. These findings delineate two different populations of hepatocellular carcinoma in Southern Africa.  相似文献   
105.
We present a case of Merkel cell carcinoma of the thigh diagnosed by conventional histology, immunohistochemistry, electron microscopy and cytogenetics. A unique chromosome 6 trisomy characterized this primary neoplasm, as confirmed by FISH study. The role of chromosome analysis and interphase cytogenetics is emphasized as an adjunct in the subtyping of tumours and their prognostic evaluation.  相似文献   
106.
应用显微分光光度计测定15例鼻咽癌19处癌旁病变的上皮细胞核DNA含量并与浸润癌相比较。中、重度异型增生上皮细胞核DI及超过2.5c细胞的百分数处于单纯增生+轻度异型增生与浸润癌之间,3组DI及超过2.5c细胞的百分数差异显著。中、重度异型增生以非整倍体为主,其细胞核DNA含量组方图相似于浸润癌。从细胞核DNA含量角度来看,中、重度异型增生是重要的癌前病变。  相似文献   
107.
Summary An analysis of autopsy data shows that during the period 1928–1972 the relative frequency of carcinoma of the stomach has remained practically unchanged. A similar trend is apparant from the mortality statistics for Vienna from 1955 to 1972. Whereas for the lower and middle age groups there is a real decrease during the period 1928–1952, an opposite trend is visible for the highest age group. The stomach and the lower parts of the large intestine are the most frequent sites of carcinoma of the alimentary canal. The frequency distribution is explained on the basis of the contact hypothesis.  相似文献   
108.
Lymphoepithelioma-like carcinoma of the bladder is an uncommon neoplasm, of which 49 cases have been described in the English literature, none of which has been studied for p53 protein expression. We studied three muscle-infiltrating cases of this tumor using immunohistochemical, in situ hybridization and polymerase chain reaction (PCR) methods. The three cases were positive for epithelial markers and negative for lymphoid antigens in the tumoral syncytial areas. The intensive infiltrate of small cells was negative for epithelial and positive for lymphoid markers. This population was mainly made up of cytotoxic T-lymphocytes, positive for TIA-1. p53 protein was intensely positive in more than 90% of the epithelial component nuclei, being negative in the lymphoid cells. PCR study did not show mutations on p53. Both lymphocytes and epithelium were negative for Epstein–Barr virus markers, such as the latent membrane protein and EBER (Epstein–Barr-encoded RNA). The prognosis was very good after radiotherapy and chemotherapy treatment, preserving the bladder despite the muscle infiltration. The presence of an intense cytotoxic T-lymphocyte population may be related to this good prognosis. Both aspects, p53 protein status and T-lymphoid population, had never been studied before in bladder lymphoepithelioma-like carcinoma.  相似文献   
109.
The etiological role of human papillomavirus (HPV) in esophageal carcinoma (EC) in relation to p53, mdm2, p21(waf), c-erbB2 and the overall survival (OS) rate was investigated. Tumor and normal tissues from 50 EC were evaluated by polymerase chain reaction and InnoLiPA for HPV. Single strand conformation polymorphism/sequencing were used to detect p53 gene mutations. Immunohistochemistry was performed to determine p53, mdm2, p21(waf)and c-erbB2 expression. Human papillomavirus was detected in 54% of tumors and in 24% of normal tissues. p53, mdm2 and c-erbB2 overexpression was detected in 68%, 70% and 60% of tumors and in 14%, 16% and 10% of normal samples, whereas loss of p21(waf) was evident in 64% of tumors. p53 mutations were detected in 20% of cases. Exon 8 and 5 showed the highest mutation rate (40% each), followed by exons 6 and 7 (10% each). There was a significant correlation between HPV and p53, mdm2, c-erbB2 overexpression. The OS was significantly associated with overexpression of p53 and loss of p21(waf). Human papillomavirus infection is frequent in Egyptian EC. Both p53-dependent and p53-independent pathways seem to be involved in HPV-associated EC. mdm2 and c-erbB2 are possible targets for HPV in the p53-independent pathway. However, only advanced stage and aberrant expression of p53 and p21(waf) are independent prognostic markers.  相似文献   
110.
Cell surface carbohydrates are involved in many cell functions such as cellular differentiation, adhesion, and invasion. A carbohydrate, sialosyl-Tn (STn), is expressed in many human carcinomas but generally not in normal epithelia. In the oral mucosa, however, STn had recently been observed on basal cell in some lesions with epithelial hyperplasia and dysplasia. The aim of this study was to carry out a systematic investigation of STn expression on epithelial basal cells in hyperplastic, ‘borderline’ malignant, and malignant head and neck lesions, to see if the expression of STn is associated specifically with hyperplastic conditions. Using the primary monoclonal antibody TKH2, normal controls did not reveal STn. STn was detected on probably post-mitotic basal cells in hyperplastic head and neck lesions and on basal cells adjacent to cancers, but not within the carcinomas. A Ki67 antibody reacted with basal cells in other locations. The most highly differentiated lesions, such as focal epithelial hyperplasia and verrucous hyperplasia, revealed a high percentage (86 per cent in both cases) of STn reactivity. The least-differentiated verrucous carcinomas (VCs) and keratoacanthomas (KAs) did not express STn, in contrast to the highly differentiated VCs and KAs. These findings indicate that STn-negative cases may have a greater malignant potential that the STn-positive cases. In conclusion, STn expressed on basal cells is possibly a marker for non-malignant conditions with altered basal cell activity and for highly differentiated verrucous carcinomas.  相似文献   
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