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F Beuvon

Publications and source records attributed to F Beuvon.

33 records · Page 2Linked to original sources
PubMed1997

Oligodendrogliomas. Part II: A new grading system based on morphological and imaging criteria.

This second part of our study of 'pure' oligodendrogliomas focuses on survival data analysis. In order to identify potentially useful prognostic factors and to assess the effectiveness of a new grading system, the 79 patients in the previously analyzed series for whom adequate follow-up could be obtained (52%) were entered in the present analysis. Statistical analysis demonstrated that contrast enhancement and endothelial hyperplasia had powerful and similar influence on survival. Median survival with and without contrast enhancement were: 3 versus 11 years, and with or without endothelial hyperplasia were: 3.5 versus 11 years. Conversely, the degree of nuclear atypia and presence or absence of mitosis or necrosis were not correlated with survival. These findings allowed us to devise a simple grading system which discriminates two malignancy grades as follows: absence of endothelial hyperplasia and of contrast enhancement = Grade A, presence of endothelial hyperplasia and/or of contrast enhancement = Grade B. Of the 79 oligodendrogliomas in this study, 59 tumors were categorized as grade A and 20 as grade B. Median survival were: 11 years in grade A and 3.5 years in grade B. Five-year and 8-year survival rates were: 89% and 60% in grade A and: 33% and 15% in grade B. Double blind grading between two independent observers was concordant in 96% of the cases. Application of this simple efficient and reproducible grading scheme should permit reliable comparison of retrospective or prospective therapeutic data emanating from various institutions.

Brain Neoplasms↗
PubMed1997

Characterization of stable RNAs from the resected intestinal tissues of individuals with either Crohn's disease or ulcerative colitis.

Circular RNAs reminiscent of viroids and the human hepatitis delta virus have been proposed as possible nonconventional pathogens responsible for Crohn's disease and ulcerative colitis, two inflammatory bowel diseases. Consequently, RNA was extracted from various areas of intestinal tissues from individuals with either Crohn's disease or ulcerative colitis as well as several appropriate control diseases, and analyzed by two-dimensional gel electrophoresis. No circular viroid-like RNAs (< 1500 nucleotides) were detected, confirming a previous report that was limited to the investigation of small RNAs (< 300 nucleotides). However, three small, unusually stable, linear RNAs were shown to be associated to both Crohn's disease and ulcerative colitis tissues: a specific 28S ribosomal RNA cleavage product characterized previously; a 5.8S ribosomal RNA conformer; and a fragment homologous to transcripts from DNA CpG islands. The two last RNAs were detected prior to visible morphological tissue alterations, suggesting that they are produced early during the inflammation and that they have value as molecular diagnostic tools for the inflammatory bowel diseases. The potential cellular mechanisms producing these RNAs and their involvement in inflammatory bowel disease are discussed.

Colitis, Ulcerative↗
PubMed1995

Rapid washout of technetium-99m-MIBI from a large parathyroid adenoma.

We report a case of rapid 99mTc-methoxyisobutylisonitrile (MIBI) clearance from a parathyroid adenoma. A double-phase 99mTc-MIBI parathyroid scintigraphy was performed on a 62-yr-old female evaluated for primary hyperparathyroidism. A large parathyroid adenoma was visualized caudal to the left lobe of the thyroid gland with an unusually rapid washout of the tracer from tumor tissue. Histologic tissue examination confirmed the presence of a parathyroid adenoma and the absence of oxyphil cells. Care should be taken in interpretation of 99mTc-MIBI parathyroid scintigrams because some adenomas can present a rapid release of the radiotracer in a double-phase study. Technetium-99m-MIBI retention could be related to the number of mitochondria-rich cells in parathyroid adenomas or to hyperplasia.

Adenoma↗
PubMed1994

Anti-colony-stimulating factor-1 antibody staining in primary breast adenocarcinomas correlates with marked inflammatory cell infiltrates and prognosis.

BACKGROUND: Clinical studies have shown that a marked lymphoplasmocytic reaction in breast tumors is associated with poor prognosis. Such findings raise the possibility that an inflammatory cell reaction might be a tumor-induced response that tends to promote tumor growth. PURPOSE: We assessed the expression of colony-stimulating factor-1 (CSF-1) as well as the prevalence of specific tumor-infiltrating lymphocytes and monocytes in breast tumors. METHODS: Tissue sections were obtained from archival paraffin blocks from 196 breast cancer patients. Seventy-eight percent of the women had been treated by mastectomy and 22% by lumpectomy. Median age of the patients was 54 years, and median follow-up was 7.3 years. Immunohistochemical and in situ hybridization techniques were used to characterize the specimens. RESULTS: Markedly high numbers of CD45RO-positive T- and L26-positive B-cell infiltrates were found in 13% and 17% of the tissue specimens, respectively. CSF-1 receptor-positive monocytes were detected in 48% and CD68-positive monocytes in 90% of the tumors. In turn, tumors with large fractions of CD68-positive monocytes also showed CSF-1 receptor-positive monocytes (P < .0001). CSF-1 was expressed significantly in 74% of the tumors and the CSF-1 receptor in more than 50% of the tumors. Tumors with high percentages of CSF-1 expressing cells also had marked monocyte infiltrates (P = .035). The presence of marked CD45RO-positive T-cell infiltrates and apparent nuclear staining of CSF-1 in tumor cells were associated with the more frequent occurrence of metastases (P = .02 and P = .04, respectively) and with poor survival (P = .02 and P = .03, respectively). CONCLUSIONS: Large numbers of CD45RO-positive (activated memory but noncytotoxic) T cells as well as a predominant nuclear staining pattern for CSF-1 are associated with a poor outcome in breast cancer patients. IMPLICATIONS: Nuclear retention of CSF-1 could reflect CSF-1 turnover and function in tumor cells, but new approaches are needed to establish the significance of these observations. Secreted CSF-1 appears to cause monocyte recruitment and activation, thereby modulating immune functions and potentially the expression of the CD45RO phenotype in T cells.

Adenocarcinoma↗
PubMed1993

[CSF-1 (colony stimulating factors 1) and CSF-1 receptor. General review and expression in invasive breast tumors].

CSF-1 (colony stimulating factor-1), initially considered to be a monocyte specific growth and differentiation factor [4], has recently been shown to be produced in human endometrium [16], placenta [7], as well as in numerous solid tumors [19-23, 26, 27]. The CSF-1 receptor (a protein product of c-fms) [24] is a member of the tyrosine kinase receptor family and an autocrine or paracrine mechanism of activation has been suggested. Overactivation of this receptor can lead to a malignant phenotype in various cell systems [20, 21]. We review the biology of CSF-1 and fms expression in normal as well as in malignant tissues with particular reference to a potential role for CSF-1 in breast tumour invasion.

Adenocarcinoma↗
PubMed1993

[Necrotizing sialometaplasia: an ignored disease].

Necrotizing sialometaplasia is an ignored pathology. Differential diagnosis has to be made with a neoplasm. The presented case is characterized by an important bone defect, which, to our knowledge, has never been reported.

Biopsy↗
PubMed1992

M-CSF (monocyte colony stimulating factor) and M-CSF receptor expression by breast tumour cells: M-CSF mediated recruitment of tumour infiltrating monocytes?

Infiltrating immune cells in 30 primary human epithelial breast tumours were studied using specific anti-CD3 (T cells), anti-CD68 (macrophages), anti-CD57 (NK cells), and an anti-pan-B cell antibody (L26). The majority of tumour infiltrating inflammatory cells are T cells (40-50%) and monocytes/macrophages (15-35%). The macrophage specific chemo-attractant and growth factor CSF-1 is detected by immunohistochemical techniques (IHC) at the level of invasive breast cancer cells in 46/50 tumours but not at the level of in-situ (pre-invasive) cancer. A mosaic staining pattern was usually observed, with a very high expression in areas of obvious stromal invasion (90% cells positive) and absent or trace staining in intraductal carcinoma. Macrophages and plasma cells are equally intensely positive. In-situ hybridisation experiments confirm the production of CSF-1 (mRNA) by tumour cells and show the same pattern of expression. Expression of the CSF-1 receptor protein (fms) was also observed by IHC in 41/48 invasive tumours, albeit at weaker intensities than in tumour infiltrating monocytes/macrophages. A concomitant expression of both CSF-1 and fms in in-situ carcinoma was never seen (n = 14). It is therefore proposed that the associated expression of CSF-1 and its receptor may be linked to the invasive potential of breast cancer, the monocytic infiltrate being an indication of the quantitative importance of CSF-1 production by the tumour.

Antibodies, Monoclonal↗
PubMed1992

[Stereotaxic laser interstitial thermotherapy. A new alternative in the therapeutic management of some brain tumors].

Laser Interstitial Thermo Therapy (ITT) is a new procedure which has been performed only a few times in our department as well as in foreign services. The aim of an ITT is to increase the temperature of a tumoral target which has been perfectly determined stereotactically. In the center of the target, i-e at the extremity of the laser fibre, temperature reaches 80 degrees 90 degrees C and creates a coagulation necrosis. At the periphery of the target, temperature must be 41 degrees-43 degrees C so as to create a selective lesion of the pathological tissue due to proteinic and enzymatic denaturation. The authors present their experience based on 8 patients who underwent an ITT between June 1990 and October 1991. A stereotactic determination of the tumor is first performed; then two routes are determined for the laser-fibre (Nd-YAG 1.06 microns, fiber diameter: 400 mu) and for the thermic electrode. The ITT itself is performed a few days later (P = 3-5w, time: 800-1200 seconds). Laser heat effects are monitored with MRI controls (H5, H24, D8 then monthly). The authors insist on the importance of a long follow-up so as to be sure of the complete inocuity of such a treatment. It is the only way to broaden and develop laser-ITT procedures as therapeutic alternatives for certain deep-seated intracerebral tumors.

Brain Neoplasms↗
PubMed1991

[Radiation-induced neurosarcoma. Clinical, histological and immunohistochemistry aspects].

The authors report on a case of radiation-induced malignant Triton tumor eg malignant schwannoma with rhabdomyoblastic differentiation). The tumor was situated in the brachial plexus of a patient who had received irradiation therapy 20 years previously for breast carcinoma. Pathological and immunohistological features have been described: coexpression of PS100, vimentin and desmin indicate a common neuroectodermic origin. A review of the literature has been presented in order to evaluate the diagnostic and prognostic characteristics of this unusual tumor and its relationship to neurofibromatosis.

Brachial Plexus↗
PubMed1990

Oncogene amplification correlates with dense lymphocyte infiltration in human breast cancers: a role for hematopoietic growth factor release by tumor cells?

One hundred six primary breast cancer samples were analysed for c-erbB2, int-2, and c-myc gene amplification. Surgically confirmed nodal involvement was observed in 42%. Level of gene amplification was studied by Southern and/or slot blot techniques. Amplified c-erbB2 gene sequences were present in 21.5% of all samples. Int-2 was amplified in 13.1% and c-myc was amplified in 10.3%. In a non-parametric test (Kruskal-Wallis) a strong negative association was found between high levels of c-erbB2 amplification and absence of estrogen receptor (ER) (P = .0009) or progesterone receptor (PR) (P = .011) expression. No correlations were found between all or high levels of amplification of each oncogene separately or combined with T, N, grade, multifocality of tumor, or associated carcinoma in situ. There was a trend approaching statistical significance for patients with c-erbB2 amplifications to have positive lymph nodes at surgery (P = 0.09). A somewhat surprising finding however was a very strong association between oncogene amplification and dense lymphocyte infiltration of the tumor (P = .05). This correlation is even stronger when only high levels of amplification are considered, either for each oncogene separately (P = .0048) or in combination (P = .0007). We propose that malignant cell cytokine production may help explain this observation.

Breast Neoplasms↗
PubMedDate not supplied

[Flow cytometry of polypoid neoplasms of the colon resected by endoscopy].

Sixty-one neoplastic polypoid lesions of the large bowel and rectum, obtained by endoscopic resection, were submitted to cytofluorometric measurements. This study was performed on archival formalin fixed and paraffin embedded material using the method of Hedley. Coefficient of variation, DNA Index, DNA aneuploidy, proliferative activity were statistically correlated to histological grading (according to U.I.C.C.) and to the presence of trophic changes (epithelial displacement, hemorrhage, mucus discharge. Compared with morphological findings, cytofluorometric results revealed that DNA aneuploidy appeared only when intraepithelial carcinomatous changes were present, and was found in 50 percent of microinvasive carcinoma. The proliferative activity was significantly increased in intraepithelial carcinomas, with a significant enlargement of the coefficient of variation. This change may reflect initial disorders in DNA content of neoplastic cells. On the other hand, there was no significant difference between lesions with and without trophic alterations. These findings confirm that this increase is an independent phenomenon during tumor progression.

Adenocarcinoma↗