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C Duval

Publications and source records attributed to C Duval.

At least 37 records · Page 2Linked to original sources
PubMed1999

[Primary pleural lymphoma after collapse therapy: modern aspects of an historic disease].

INTRODUCTION: Pleural lymphomas after long standing pyothorax due to pulmonary tuberculosis are now well identified. Most cases have been described by Japanese investigators and it seems rare or unrecognised in Western countries. We report the study of six cases observed in a single institution. PATIENTS AND METHODS: Six pyothorax-associated pleural lymphomas, among 1,038 lymphoma (0.6%) collected during a period from 1989 to 1998, are described. Diagnosis was established by two pathologists with the usual histologic and immunohistochemical methods, according to the working formulation. The in situ hybridization method for Epstein-Barr virus was performed. RESULTS: The average age of the patient was 73 years. Presenting symptoms combined chest pain and constitutional symptoms more than 45 years after artificial pneumothorax or tuberculous pleuritis. Computerized tomography revealed a pleural mass which involved the adjacent chest wall. Open biopsy by thoracotomy show a diffuse B-cell non-Hodgkin-lymphoma in all cases. Though the lymphoma was initially localized, many poor prognostic factors (age, performance status, LDH, histology) explain the pejorative evolution (average survival of five months). Patients died from an uncontrolled tumoral proliferation or by infectious complications. In situ hybridization confirms the presence of Epstein-Barr virus in tumoral cells. CONCLUSION: Pleural lymphoma is an established complication of artificial pneumothorax. Even if the Epstein-Barr virus plays a crucial role in the pathogenesis, and despite the number of artificial pneumothorax operations that have been widely performed, this lymphoma remains rare, suggesting additional oncogenic factors.

Aged↗
PubMed1999

The utility of mitotic index, oestrogen receptor and Ki-67 measurements in the creation of novel prognostic indices for node-negative breast cancer.

INTRODUCTION: Prognostic factors can be useful to identify node-negative patients at increased risk of relapse who should receive adjuvant treatment. In the past, oestrogen receptor status and mitotic index have been shown to be significant predictors of prognosis. Different techniques for the measurement of these prognostic factors are available. METHODS: Paraffin-embedded tumour specimens from 441 pre-menopausal patients with node-negative breast cancer who were previously randomized onto a trial comparing peri-operative chemotherapy with no further therapy were studied. Oestrogen receptor status was determined by the classical biochemical assay and by immunohistochemistry (ER-IA). Mitotic index was assessed by counting the number of mitoses and by calculating the percentage of tumour cells positively staining for the antibody Ki-67. RESULTS: There was a good correlation between ER-IA and the biochemical ER-assay (P<0.01), and the percentage of Ki-67 positive tumour cells and mitotic counts (P<0.01) respectively. However, ER-IA significantly predicted disease-free survival (RR=2.67, 95% CI: 1.60-4.44, P<0.01) whereas the biochemical assay was only borderline significant (RR=1.54, 95% CI: 1.00-2.36, P=0.05). Similarly, Ki-67 was a stronger indicator of prognosis (RR=2.84, 95% CI: 1.80-4.48, P<0.01) than mitotic counts (RR=1.56, 95% CI: 1.22-2. 00, P<0.01). CONCLUSIONS: We conclude that ER-IA performs better in predicting prognosis than the classical biochemical oestrogen receptor assay. Ki-67 is a more accurate marker for tumour cell proliferation and predicts prognosis of patients with breast cancer better than do mitotic counts.

Adult↗
PubMed1999

Incidence of rectosigmoid adenomatous polyps in subjects without prior colorectal adenoma or cancer: a prospective cohort study.

BACKGROUND: Subjects without known colorectal adenomas or cancer constitute a large majority of the population where 85% of all cases of colorectal cancer are thought to occur. Consequently these people should be considered for screening to decrease mortality from colorectal cancer in the general population. AIMS: To estimate the incidence rate of rectosigmoid adenomas in these subjects. METHODS: Subjects without adenomas or cancer at a previous examination which had visualised the rectosigmoid underwent a fibre endoscopy every three years. Endoscopic data and population characteristics were collected prospectively. RESULTS: A total of 450 subjects fulfilled the selection criteria; 287 (64%) underwent at least two examinations, and 163 had three or more. At the second examination, with a mean delay of 39 months, the incidence rate of rectosigmoïd adenomas was 1.50% per patient year. The rate was 1.75% per patient year (95% CI 0.80-3.33) at the third endoscopy with an additional mean delay of 38 months. The cumulative incidence rate at six years was 7.3% (95% CI 4.3-10.3), representing a mean of 1.2% per patient year. This rate increased with age and was higher for men than for women after age adjustment (p< 0.03). CONCLUSIONS: The incidence rates are very low compared with those of patients with prior adenomas. These results should be considered in establishing rectosigmoid adenoma screening strategies.

Adenomatous Polyps↗
PubMed1999

Keratinocyte-melanocyte co-cultures and pigmented reconstructed human epidermis: models to study modulation of melanogenesis.

Normal human melanocytes were amplified and cultured in a new defined culture medium without phorbol esters or cholera toxin. The medium decreased considerably the doubling time and increased the possible passage number. Melanocytes were co-seeded with normal human keratinocytes into 24 well culture dishes to screen potentially active modulators of melanogenesis. For the assay, the co-cultures were exposed to the compounds under investigation in the presence of 14C-thiouracil and 3H-leucine. Control cultures contain L-tyrosine or kojic acid, modulators which served as internal calibration standards. Changes in the rate of melanin synthesis were measured on the basis of 14C-thiouracil incorporation into newly synthesized melanin. A reduction or increase in 3H-leucine incorporation was taken as an indication of cytotoxicity or induction of proliferation, respectively. The NHK-NHM co-culture screening assay provides a useful tool to compare the activity of known modulators of melanogenesis and to perform structure-activity studies with newly identified modulators to improve their activity. The efficacy of particularly interesting new compounds was further evaluated on reconstructed pigmented epidermis after repeated topical application. The same model was used to assess the anti-pigmenting effect of sunscreens on UV-induced pigmentation. Integration of melanocytes from different ethnic origin resulted in pigmented epidermis reflecting different skin phenotypes, Caucasian, Asian and African.

1-Methyl-3-isobutylxanthine↗
PubMed1998

p53 protein accumulation and response to adjuvant chemotherapy in premenopausal women with node-negative early breast cancer.

PURPOSE: Thirty percent of women with node-negative breast cancer will have a recurrence within 10 years after diagnosis. Molecular markers may identify those patients and predict whether they benefit from adjuvant therapy. The European Organization for Research and Treatment of Cancer (EORTC) conducted a randomized trial (EORTC 10854) to compare perioperative treatment with one course of fluorouracil, doxorubicin, and cyclophosphamide (FAC) versus no further therapy. We studied tumors from premenopausal patients with node-negative breast cancer randomized in this trial to determine whether p53 accumulation, c-erbB-2 expression, percentage of Ki-67-positive cells, estrogen receptor (ER-immunoassay [IA]), progesterone receptor (PR-IA), and angiogenesis could be used as prognostic factors and predictors of responsiveness to adjuvant chemotherapy. PATIENTS AND METHODS: Paraffin-embedded tumor specimens from 441 premenopausal women with node-negative breast cancer were collected from the larger EORTC trial. Paraffin sections from the tumors were analyzed for immunohistochemical expression of p53, c-erbB-2, Ki-67, ER, PR, and angiogenesis. RESULTS: Patients with p53-negative tumors showed a significant benefit from perioperative chemotherapy (P < .01), whereas patients who had p53-positive tumors did not (P = .80). At a median follow-up time of 49 months, univariate analyses for disease-free survival (DFS) failed to show prognostic value for p53, c-erbB-2 and angiogenesis. Both univariate and multivariate results showed Ki-67 positivity, ER-IA negativity, and a younger age to be associated with a worse prognosis. CONCLUSION: p53 accumulation was associated with a poor response to one perioperative course of FAC chemotherapy. Ki-67, ER-IA, and age are important prognostic factors in premenopausal women with node-negative breast cancer.

Adult↗
PubMed1997

Increased hyaluronidase levels in breast tumor metastases.

Hyaluronidase, a matrix-degrading enzyme, was assayed in extracts from breast primary tumors and regional metastases using a pool of human sera as a standard. Optimal activities of tumor extracts and serum were found for concentrations of 0.15-0.20 M NaCl in pH 3.8-4.0 buffer. In evaluating contamination by serum due to vascular proliferation, we expressed our results as the ratio of the entire activity (mU/l extract) on serum albumin content of tumors (g/l). Median (interquartile range) activities were 9.02 (6.04-14.34) for primary tumors and 37.36 (24.06-99.63) mU/g albumin for metastases. The difference was significant. Zymographic analysis showed that 3 bands of activity were detected which corresponded to 68, 53 and 49 kDa for tumoral hyaluronidase. The same pattern was observed for cellular extracts of breast cancer cell line CAL51, demonstrating that hyaluronidase detected in tumor extracts had mainly a cellular origin. Our results suggest that hyaluronidase may be involved in the metastatic process.

Breast Neoplasms↗
PubMed1997

The origin of hyaluronectin in human tumors.

The origin of tumor stroma hyaluronectin (HN), a glycoprotein that binds to hyaluronan (HA), has long remained unknown. Histological observations of human tumors suggest that tumor HN could originate from stroma fibroblasts, and in some cases from inflammatory cells. The fibroblast origin was confirmed by the discovery of HN-like antigen along with hyaluronan in culture medium of tumor-derived fibroblasts. An HA-binding protein was characterized in the culture medium of peripheral blood mononuclear cells (PBMC) in both normal subjects and tumor-bearing patients and was found to be human HN. Cultivated monocytes did not produce HA. HN was not related to the HA-binding site CD44. Sequencing of brain HN-derived peptides demonstrated that each determined peptide sequence was similar to a sequence of the proteoglycan PG-M/versican, suggesting that HN is the HA-binding moiety of the proteoglycan. One probe was synthesized from human PBMC by polymerase chain reaction with primers derived from HN sequences also found in versican. Northern blots were positive only with HN-producing cells. The main RNAs were in the 6-8 kb range, and there was a limited proportion of smaller RNA, which was compatible with the size expected from the HN molecular mass. Southern blotting of monocytes and tumor cells demonstrated that the gene was limited to a unique band. We conclude that HN, an extracellular component of brain, connective embryonic, inflammatory and tumoral tissues, is a PG-M/versican-derived molecule. Our results suggest that tumor HN, which originates from fibroblasts and monocytes of tumor stroma, is a molecular component of the host-tumor relationship and could play a role in the regulation of HA activity in oncogenesis.

Adenocarcinoma↗
PubMed1996

Expression of Bcl-2 in node-negative breast cancer is associated with various prognostic factors, but does not predict response to one course of perioperative chemotherapy.

The aim of this study was to assess relationships between Bcl-2 expression, response to chemotherapy and a number of pathological and biological tumour parameters in premenopausal, lymph node-negative breast cancer patients. Expression of Bcl-2 was determined using immunohistochemistry on paraffin-embedded sections in a series of 441 premenopausal, lymph node-negative breast cancers of patients randomised to receive perioperative chemotherapy (5-fluorouracil, doxorubicin, cyclophosphamide) or no perioperative chemotherapy. Immunohistochemistry of Bcl-2 was evaluated by scoring both staining intensity (0-3) and number of positive cells (0-2). Using these scores tumours were grouped into categories 0-6. It was found that 9.2% of the tumours were completely negative (0), 17.2% weakly (1 + 2), 41.6% moderately (3 + 4) and 31.9% strongly positive (5 + 6) for Bcl-2. A positive correlation was found between high Bcl-2 expression and oestrogen (P < 0.001) and progesterone receptor positivity (P < 0.001) and low tumour grade (P < 0.001), whereas high Bcl-2 expression was negatively correlated with p53 (P < 0.001) and c-erb-B-2 positively (P < 0.001), high Ki-67 index (P < 0.001), mitotic index (P < 0.001) and large tumour size (P = 0.006). Patients with tumours expressing high levels of Bcl-2 (overall score 3-6) had a significantly better disease-free (P = 0.004) and overall (P = 0.009) survival. However, in a multivariate model this association no longer remained significant. There was a trend for an effect of adjuvant chemotherapy on disease-free survival both for patients with Bcl-2-positive (HR-0.61, 95% CI 0.35-1.06, P = 0.07) and negative (HR = 0.55, 95% CI 0.27-1.12, P = 0.09) breast tumours at a median follow-up of 49 months. The level of Bcl-2 expression does not seem to predict response to perioperative chemotherapy in premenopausal, lymph node-negative breast cancer patients. High levels of Bcl-2 are preferentially expressed in well-differentiated tumours and are associated with favourable prognosis. However, Bcl-2 expression is not an independent prognostic factor in this patient series.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1995

Scavenger effect of vitamin E and derivatives on free radicals generated by photoirradiated pheomelanin.

The free radical scavenger properties of vitamin E (DL-alpha-tocopherol), a natural antioxidant, and derivatives were studied using an original in vitro method consisting of free radical production by photoirradiation of pheomelanin and direct detection of the free radicals by a physical, specific technique, electron spin resonance. Validation of this method has been realized using well-known biological free radical scavengers, superoxide dismutase and reduced glutathione. DL-alpha-Tocopherol, tocopheryl acetate, tocopheryl linoleate, and tocopheryl polyoxyethylene (POE) succinate induced a significant diminution of the free radical production. In order of efficiency, tocopheryl POE succinate was the best scavenger (37.6% inhibition at 0.25%) followed by tocopheryl linoleate (25.6% inhibition at 1%) and tocopheryl acetate (23.9% inhibition at 0.5%) and finally DL-alpha-tocopherol (16.2% inhibition at 0.05%). The results reported a decrease of the inhibitory effect for high concentrations of DL-alpha-tocopherol (0.1%) and tocopheryl acetate (1%), showing a tendency of this compound to act as a prooxidant. Used in optimal concentrations in cosmetologic or dermatologic formulations, Vitamin E and these derivatives should prevent or reduce the harmful activity of free radicals in the skin.

Animals↗
PubMed1995

Discordant malignant lymphoma synchronous or successive high-grade B lymphoma associated with Hodgkin's disease. A clinico pathologic and immunophenotypic study of 4 cases.

We report in 4 patients the rare association of Hodgkin's disease and high grade B malignant lymphoma. In 2 cases, both tumours were disclosed at the same time but in different tissues from the same region. In the 2 other patients, the second tumour was found 11 months and 12 months after the first respectively. In all cases Hodgkin's disease was of the nodular sclerosing type, the tumour cells expressing CD 30 and CD 15. The high grade lymphomas were of the polymorphic centroblastic (large non cleaved) type and expressed the B markers. One (case 4) was secondary to a follicular lymphoma. In 2 cases (2 and 4) the search for a latent EBV infection was negative in both tumours. In case 1, only the Reed-Sternberg cells were positive with both techniques. Such an association is different from so-called composite lymphomas, and can be called "discordant lymphoma". Different related conditions are discussed. This association is distinct from lymphomas or Hodgkin's disease complicating the treatment of Hodgkin's disease or malignant lymphomas.

Adult↗
PubMed1994

LAZ3 rearrangements in non-Hodgkin's lymphoma: correlation with histology, immunophenotype, karyotype, and clinical outcome in 217 patients.

We have recently shown that an evolutionary conserved gene LAZ3, encoding a zinc finger protein, is disrupted and overexpressed in some B-cell lymphomas (mainly with a large cell component) that show chromosomal rearrangements involving 3q27. Because the breakpoints involved in these rearrangements are focused in a narrow major translocation cluster (MTC) on chromosome 3, we used genomic probes from this region to study the molecular rearrangements of LAZ3 in a large series of patients (217) with non-Hodgkin's lymphoma (NHL). Southern blot analysis showed LAZ3 rearrangement in 43 patients (19.8%). Rearrangement was found in 11 of the 84 patients (13%) with follicular lymphoma but was most frequent in aggressive lymphoma (diffuse mixed, diffuse large cell, and large cell immunoblastic subtypes), in which 31 of the 114 patients (27%) were affected. The highest proportion of LAZ3 alteration was observed in B-cell aggressive lymphoma (26 of 71 cases, 37%). Eleven of the 32 patients with 3q27 chromosomal abnormality had no LAZ3 rearrangement, suggesting the possibility of LAZ3 involvement outside the MTC. On the other hand, 18 of the 39 patients with LAZ3 rearrangement and available cytogenetic results did not have visible chromosomal break at 3q27, suggesting that almost a half of the rearrangements are not detectable by cytogenetic methods. No statistical association could be found between LAZ3 status and initial features of the disease or clinical outcome in either follicular or aggressive lymphomas. We conclude that LAZ3 alteration is a relatively frequent event in B-cell lymphoma, especially in those of aggressive histology. It could be used as a genomic marker of the disease, and further studies are needed to clarify clinical implications of these alterations.

Blotting, Southern↗
PubMed1994

Expression of opioid peptides in cells and stroma of human breast cancer and adenofibromas.

The expression of beta-endorphin, Met-enkephalin and Leu-enkephalin was studied in 63 malignant and benign human breast tumors using immunohistochemical methods. Among invasive ductal carcinomas, 93% were positive for beta-endorphin, 87% for Leu-enkephalin and 90% for Met-enkephalin, in both the tumor stroma and the cell bodies. Enkephalin was predominant in cells, whereas endorphin was predominant in stroma. Nearly the same distribution was found in adenofibromas. In pericancerous normal tissue, neuropeptides were predominantly expressed in the stroma. Although the neuropeptide expression is not cancer-specific, it could be cancer-related, since the results suggest that the neuropeptide expression could reflect the host response to cancer cells and not only the cancer cell activity. The possibility of a direct action of the nervous system on stroma reaction and then on cancer cells is discussed.

Adenofibroma↗