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Biomedical subjects

F Paraf

Publications and source records attributed to F Paraf.

At least 19 recordsLinked to original sources
PubMed1995

Expression of bcl-2 oncoprotein in renal cell tumours.

Expression of bcl-2 is associated with inhibition of apoptosis and extension of cell survival. The importance of apoptosis in relation to the development and progression of renal cell neoplasia remains undefined so far. In order to determine the expression of bcl-2 oncoprotein in normal and neoplastic renal cells, 37 renal tumours were investigated by immunolabelling, including 13 clear cell carcinomas, ten tubulopapillary carcinomas, four chromophobic renal cell carcinomas, and ten oncocytomas. Twenty-six samples of adjacent normal renal tissue served as controls. bcl-2 expression was correlated with cell proliferation activity as estimated by Ki67 antigen expression, and p53 protein expression in the tumour samples. The results demonstrate that in the normal kidney, positive bcl-2 immunostaining was present in glomerular parietal epithelial cells, in distal tubular cells, and in sparse proximal tubule cells. Renal cell tumours showed heterogeneous bcl-2 expression according to the tumour cell type. While the majority of carcinomas of clear cell type were usually negative or contained sparsely distributed positive cells, all tubulopapillary carcinomas were consistently positive for bcl-2. In oncocytomas and chromophobic carcinomas, there was a low percentage of bcl-2 immunoreactive tumour cells; some nuclear bcl-2 positivity was detected in one chromophobic tumour. These findings indicate variable bcl-2 oncoprotein expression in different types of renal cell tumours, with the highest level of expression in tubulopapillary carcinomas. No clear relationship was found between nuclear grade, cell proliferation activity, and level of bcl-2 expression. p53 protein was detected in only one tubulopapillary carcinoma.

Biomarkers, Tumor↗
PubMed1995

Clinicopathological relevance of the association between gastrointestinal and sebaceous neoplasms: the Muir-Torre syndrome.

The association between sebaceous neoplasms of the skin and visceral cancers, known as Muir-Torre syndrome, is described in three patients, including one with an extensive history of cancer in his family. The first patient, a 54-year-old man, developed multiple sebaceous adenomas, epitheliomas, and carcinomas in association with a colonic carcinoma 6 years after cardiac transplantation. Family history in this patient disclosed colon cancer in 17 relatives. The second patient was a 51-year-old man who had recurrent adenocarcinoma of the sigmoid colon, adenocarcinoma arising in Barrett's esophagus, and sebaceous epithelioma during a period of 15 years. The third patient was a 90-year-old man with a sebaceous adenoma followed 5 months later by adenocarcinoma of the sigmoid colon with liver metastases. Muir-Torre syndrome in 129 other patients published in the literature is reviewed. Although it is a rare disease, Muir-Torre syndrome requires recognition because skin lesions may be the first sign of the syndrome and this may lead to early diagnosis of associated visceral cancers. Moreover, because this syndrome appears to be inherited, family members should be screened for visceral cancer, especially colorectal adenocarcinoma.

Adenocarcinoma, Sebaceous↗
PubMed1995

[Adenocarcinoma on villous tumor of the rectum in an adolescent].

CASE REPORT--A 15-year 6-month-old boy suffered from isolated recurrent rectal bleeding. Rectoscopy and colonoscopy allowed to identify and to excise one large size villous polyp, which was the site of dysplasia and liberkühn adenocarcinoma. Transrectal ultrasonography showed thickened mucosa and submucosa and suspect adenopathy. Proctectomy, ganglionic curage and coloanal anastomosis were then performed; one of the excised adenopathies was metastatic. The patient died twelve hours after surgery from an unexplained cardiovascular collapse. CONCLUSIONS--Unspecific symptoms of colorectal cancer explain that its diagnosis is often delayed. Prognosis is poor related to the advanced stages at diagnosis and mucinous adenocarcinomas. Better knowledge of the clinical presentations and of high risk situations as polyposis, ulcerative colitis, hereditary non polyposis colorectal cancer could improve the prognosis.

Adenocarcinoma↗
PubMed1995

Surgical pathology of adenocarcinoma arising in Barrett's esophagus. Analysis of 67 cases.

Numerous reviews of adenocarcinoma arising in Barrett's esophagus have been reported, but detailed pathologic findings or survival analysis have rarely been provided. This retrospective study analyzed 67 patients (mean age, 64 years; male-to-female ratio, 10:1) with an adenocarcinoma arising in Barrett's esophagus treated by surgical resection. Prevalence of smokers was 63%, alcohol users, 45%, and patients with hiatal hernia, 73%. Five patients had another synchronous cancer, and seven patients, previous esophageal surgery. Forty percent of the tumors were well differentiated, 31% moderately differentiated, 15% poorly differentiated, 7% mucinous, and 6% composed of signet-ring cells. Depth of invasion in the esophageal wall was limited to mucosa in 13% of cases and submucosa in 18%. Invasive adenocarcinomas extended to the muscular layer in 12% of cases, to adventitia in 33%, and to periesophageal tissue in 24%. Vascular and perineural neoplastic invasion was present in 67 and 38% of cases. Regional lymph node involvement and distant metastases were found in 51 and 9% of cases. Overall, 1-, 2-, and 5-year survival rates were 63, 41, and 32%, respectively. Five-year survival rate was significantly better for patients with superficial cancer limited to mucosa or submucosa (82 vs. 12%) or without regional lymph node involvement (59 vs. 10%). Tumor differentiation, vascular and perineural invasion, extranodal spread, distant metastases, and resection margins status also had a significant prognostic value on univariate analysis. In a multivariate Cox regression analysis for overall survival, depth of invasion in the esophageal wall and regional lymph node involvement were independent prognostic factors. Careful pathologic staging is of value in determining the prognosis of patients with adenocarcinoma arising in Barrett's esophagus.

Adenocarcinoma↗
PubMed1994

Expression of c-erbB-2 oncogene product in Barrett's adenocarcinoma: pathological and prognostic correlations.

AIMS: To establish the prevalence of c-erbB-2 protein expression in a surgical series of Barrett's adenocarcinomas; and to correlate this expression with clinicopathological data and prognosis. METHODS: Sixty six surgical specimens of Barrett's adenocarcinomas were included in this retrospective study. Blocks of the tumour and of non-dysplastic Barrett's mucosa were stained with a polyclonal antibody specific for the intracytoplasmic domain of the c-erbB-2 protein. RESULTS: Seven of 66 tumours showed membrane staining for the c-erbB-2 protein. The non-dysplastic Barrett's mucosa was negative in all cases. There was no difference between c-erbB-2 positive and negative tumours with regard to mean age, sex ratio, percentage of alcohol misusers, percentage of smokers, tumour differentiation, depth of invasion, lymph node response, and proliferative activity, assessed by the percentage of tumour cells positive with the MIB-1 antibody directed against the Ki-67 antigen. All c-erb B2 positive tumours were of Lauren's intestinal type compared with negative c-erbB-2 tumours. Patients with c-erbB-2 positive tumours had a significantly poorer prognosis than patients with negative tumours. CONCLUSIONS: The prevalence of Barrett's adenocarcinomas expressing c-erbB-2 found in this study (11%) was similar to that observed in published series of gastric adenocarcinomas. c-erbB-2 protein expression could be an important prognostic indicator in Barrett's adenocarcinoma.

Adenocarcinoma↗
PubMed1994

Composition of extracellular matrix and distribution of cell adhesion molecules in renal cell tumors.

BACKGROUND: Cell to cell and cell to matrix interactions play a major role in tumor growth and invasion. Therefore, we studied the composition of extracellular matrices and the distribution of cell adhesion molecules in 50 renal cell tumors of various types and various grades of malignancy as compared with nontumoral kidney. EXPERIMENTAL DESIGN: In the present study, we used immunolabeling with specific antibodies directed against the alpha 1, alpha 2, and alpha 3 chains of collagen type IV; laminin; heparan sulfate proteoglycan; fibronectin; collagen I; collagen III; the alpha 1, alpha 2, alpha 3, alpha 5, alpha 6, alpha v, beta 1, and beta 3 subunits of integrins; and ICAM-1, VCAM-1, and ELAM-1 molecules. RESULTS: In clear cell type carcinomas (24 cases) the basal laminae surrounding the tumor islets contained the alpha 1 and alpha 2 chains of collagen type IV and heparan sulfate proteoglycan in all cases, and laminin in 96% of the cases. The alpha 3 chain of collagen IV was present in only one case, whereas fibronectin, collagen I, and collagen III were detected in nearly 50% of the cases. The tumor cells expressed alpha 3, alpha 6, and beta 1 integrin subunits in all cases, alpha 5 in 25%, alpha v beta 3 in 54%, and alpha 2 in none. ICAM-1 was detected in all cases, and VCAM-1 in 58%. The expression of the alpha 6 subunit was weak in 2 tumors of high grade, whereas the alpha v subunit was expressed in 7 of 14 low grade and in 7 of 10 intermediate and high grade tumors. In tubulopapillary carcinomas with chromophilic cells (12 cases), the most prominent findings were the presence of the alpha 3 chain of collagen IV in tumor basal laminae in 66% and the expression of the alpha 2 integrin subunit by the tumor cells in 58% of the cases, both features characterizing distal renal tubules. In chromophobic carcinomas (4 cases), the tumor basement membranes were tenuous and contained no fibronectin or interstitial collagens. The tumor cells expressed the alpha 6, alpha 2, alpha 3, beta 1, and alpha nu beta 3 integrin subunits but neither ICAM-1 nor VCAM-1 molecules. In oncocytomas (10 cases), the tumor basement membranes contained the alpha 1, alpha 2, and alpha 3 chains of collagen IV, laminin, and heparan sulfate proteoglycan. Fibronectin was not detected, whereas interstitial collagens were present in half of the cases. In all tumors, cells expressed the alpha 6 and beta 1 integrin subunits, whereas alpha 2, alpha 3, and alpha nu beta 3 were present in 30%, 60%, and 90% of the cases, respectively. ICAM-1 and VCAM-1 were not detected. The vascular endothelial cells of the stroma expressed the alpha 1, alpha 5, alpha 6, and beta 1 integrin subunits in all 50 of the studied tumors. In addition, ICAM-1 was detected in 84%, VCAM-1 in 50%, and ELAM-1 in 34% irrespective of tumor cell type, growth, or nuclear grade. CONCLUSIONS: These results suggest that each type of renal cell tumor produces particular extracellular matrix components and expresses a characteristic repertoire of cell adhesion molecules, which could provide better understanding of the origin of these tumors. The expression of the alpha nu beta 3 integrin subunit was demonstrated in all types of renal cell tumors and was not found to be related to high grade tumors. Stromal vascular endothelial cells expressed activation molecules VCAM-1 and ELAM-1 in a significant number of cases in both benign and malignant tumors.

Adenocarcinoma, Clear Cell↗
PubMed1994

[Benign atypical cysts of the kidney: MRI aspects].

The aim of this study was to assess the magnetic resonance imaging (MRI) characteristics of 13 benign complex renal cysts using T1 and T2-weighted images and contrast-enhanced images. The results have been compared to CT and ultrasonographic findings in all cases and correlated with histopathologic data in 12 cases. Five groups have been defined according to the MR features. Group 1: homogeneous low signal intensity on T1-weighted images and homogeneous high signal intensity on T2-weighted images mimicking simple cyst (n = 2); group 2: homogeneous high signal intensity on both T1 and T2-weighted images mimicking hemorrhagic cyst (n = 1); group 3: caracterised by high signal intensity on T1-weighted images and fluid-iron level on T2-weighted images (n = 3); group 4: characterised by fluid-iron level on both T1 and T2-weighted images (n = 3); group 5: pseudotumoral feature: heterogeneous signal intensity and/or wall contrast enhancement (n = 3). Among the 13 indeterminate lesions on ultrasonography and CT, MRI was of diagnostic value in 8 cases, whereas the 5 remaining cases remained indeterminate on MR images. Our results suggest that MRI can be useful in the diagnosis of benign complex cyst of the kidney presenting as indeterminate cystic lesion on other modalities.

Adult↗