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Biomedical subjects

C Lasset

Publications and source records attributed to C Lasset.

At least 37 records · Page 2Linked to original sources
PubMed1998

Multifactorial analysis of differences between sporadic breast cancers and cancers involving BRCA1 and BRCA2 mutations.

BACKGROUND: We have previously demonstrated that breast cancers associated with inherited BRCA1 and BRCA2 gene mutations differ from each other in their histopathologic appearances and that each of these types differs from breast cancers in patients unselected for family history (i.e., sporadic cancers). We have now conducted a more detailed examination of cytologic and architectural features of these tumors. METHODS: Specimens of tumor tissue (5-microm-thick sections) were examined independently by two pathologists, who were unaware of the case or control subject status, for the presence of cell mitosis, lymphocytic infiltration, continuous pushing margins, and solid sheets of cancer cells; cell nuclei, cell nucleoli, cell necrosis, and cell borders were also evaluated. The resulting data were combined with previously available information on tumor type and tumor grade and further evaluated by multifactorial analysis. All statistical tests are two-sided. RESULTS: Cancers associated with BRCA1 mutations exhibited higher mitotic counts (P = .001), a greater proportion of the tumor with a continuous pushing margin (P<.0001), and more lymphocytic infiltration (P = .002) than sporadic (i.e., control) cancers. Cancers associated with BRCA2 mutations exhibited a higher score for tubule formation (fewer tubules) (P = .0002), a higher proportion of the tumor perimeter with a continuous pushing margin (P<.0001), and a lower mitotic count (P = .003) than control cancers. CONCLUSIONS: Our study has identified key features of the histologic phenotypes of breast cancers in carriers of mutant BRCA1 and BRCA2 genes. This information may improve the classification of breast cancers in individuals with a family history of the disease and may ultimately aid in the clinical management of patients.

Adult↗
PubMed1998

Iatrogenic risks of endometrial carcinoma after treatment for breast cancer in a large French case-control study. Fédération Nationale des Centres de Lutte Contre le Cancer (FNCLCC).

Since tamoxifen is widely used in breast cancer treatment and has been proposed for the prevention of breast cancer, its endometrial iatrogenic effects must be carefully examined. We have investigated the association between endometrial cancer and tamoxifen use or other treatments in women treated for breast cancer in a case-control study. Cases of endometrial cancer diagnosed after breast cancer (n = 135) and 467 controls matched for age, year of diagnosis of breast cancer and hospital and survival time with an intact uterus were included. Women who had received tamoxifen were significantly more likely to have endometrial cancer diagnosed than those who had not (crude relative risk = 4.9, p = 0.0001). Univariate and adjusted analyses showed that the risk increased with the length of treatment (p = 0.0001) or the cumulative dose of tamoxifen received (p = 0.0001), irrespective of the daily dose. Women who had undergone pelvic radiotherapy also had a higher risk (crude relative risk = 7.8, p = 0.0001). After adjusting for confounding factors, the risk was higher for tamoxifen users (p = 0.0012), treatment for more than 3 years (all p < 0.03) and pelvic radiotherapy (p = 0.012). Women who had endometrial cancer and had received tamoxifen had more advanced disease and poorer prognosis than those with endometrial cancer who had not received this treatment. Our results suggest a causal role of tamoxifen in endometrial cancer, particularly when used as currently proposed for breast cancer prevention. Pelvic radiotherapy may be an additional iatrogenic factor for women with breast cancer. Endometrial cancers diagnosed in women treated with tamoxifen have poorer prognosis. Women who receive tamoxifen for breast cancer should be offered gynaecological surveillance during and after treatment. A long-term evaluation of the risk-benefit ratio of tamoxifen as a preventive treatment for breast cancer is clearly warranted.

Adenocarcinoma↗
PubMed1998

Recombinant human interleukin-2, recombinant human interferon alfa-2a, or both in metastatic renal-cell carcinoma. Groupe Français d'Immunothérapie.

BACKGROUND: Recombinant human interleukin-2 (aldesleukin) and recombinant human interferon alfa can induce notable tumor regression in a limited number of patients with metastatic renal-cell carcinoma. We conducted a multicenter, randomized trial to determine the effect of each cytokine independently and in combination, and to identify patients who are best suited for this treatment. METHODS: Four hundred twenty-five patients with metastatic renal-cell carcinoma were randomly assigned to receive either a continuous intravenous infusion of interleukin-2, subcutaneous injections of interferon alfa-2a, or both. The main outcome measure was the response rate; secondary outcomes were the rates of event-free and overall survival. Predictive factors for response and rapid progression were identified by multivariate analysis. RESULTS: Response rates were 6.5 percent, 7.5 percent, and 18.6 percent (P<0.01) for the groups receiving interleukin-2, interferon alfa-2a, and interleukin-2 plus interferon alfa-2a, respectively. At one year, the event-free survival rates were 15 percent, 12 percent, and 20 percent, respectively (P=0.01). There was no significant difference in overall survival among the three groups. Toxic effects of therapy were more common in patients receiving interleukin-2 than in those receiving interferon alfa-2a. Response to treatment was associated with having metastasis to a single organ and with receiving the combined treatment. The probability of rapid progression of disease was at least 70 percent for patients with at least two metastatic sites, liver metastases, and a period of less than one year between the diagnosis of the primary tumor and the appearance of metastases. CONCLUSIONS: Cytokines are active in a few patients with metastatic renal-cell carcinoma. The higher response rate and longer event-free survival obtained with a combination of cytokines must be balanced against the toxicity of such treatment.

Adjuvants, Immunologic↗
PubMed1998

Multivariate analysis of risk factors in stage 4 neuroblastoma patients over the age of one year treated with megatherapy and stem-cell transplantation: a report from the European Bone Marrow Transplantation Solid Tumor Registry.

PURPOSE: The European Bone Marrow Transplantation (EBMT) Solid Tumor Registry (STR) contains detailed information on children with advanced neuroblastoma who, after standard-dose induction chemotherapy and surgery, received myeloablative megatherapy (MGT) followed by stem-cell transplantation (SCT). This data base was analyzed to identify factors that predict event-free survival (EFS). PATIENTS AND METHODS: Eligibility criteria were stage IV neuroblastoma, age over 1 year at diagnosis, and no relapse before MGT/SCT. Between February 1978 and July 1992, 549 patients were registered by 36 European transplant centers. The median age at diagnosis was 36 months (range, 13 to 216 months) and the male-female ratio was 1:45. Before MGT, 157 patients were in complete remission (CR), 156 in very good partial remission (VGPR), and 208 in partial remission (PR), whereas 24 had had only a minor response (MR). One hundred ten of 546 patients had undergone two successive MGT procedures. The median observation time was 60 months (range, 12 to 187 months). RESULTS: Actuarial EFS is 26% at 5 years. Multivariate analysis by the Cox proportional hazards regression model included 529 patients with complete data sets. After adjustment for treatment duration before MGT and double MGT procedures, two adverse, independent risk factors that influenced EFS were identified: (1) persisting skeletal lesions before MGT as defined by technetium (99TC) scans and/or meta-iodobenzylguanidine (mIBG) scans (P = .004) and (2) persisting bone marrow involvement before MGT (P = .03). CONCLUSION: After induction treatment, persisting skeletal disease as defined above and persisting bone marrow involvement may be predictive of a particularly poor outcome. Physicians may consider this an additional important tool to decide the patient's management.

Adolescent↗
PubMed1998

[The role of the medical corps in a mass screening program for cervical cancer. The program "Female Health Action in 3 urban districts of Lyons].

A pilot study of cervical cancer screening has been initiated in three districts of Lyons suburbs. This campaign aims to increase women participation, specially for high risk groups, helped by an intensive collaboration of general practitioners and gynecologists. Despite several campaign of information, a low rate of participation (13%) was noted. A survey has been performed on the medical population, notably for their participation, eventual changes, encountered problems and perception of such a screening. At time of survey, only half of the general practitioners and 75% of gynecologist still participated. Complexity of administrative procedures, involvement in an epidemiologic survey, lack of time or non-gynecological practice were important obstacles. Volunteer practitioners, enhanced value of public health and university formation of doctors could be necessary in the future for such mass screening.

Adult↗
PubMed1997

Germline hMSH2 and hMLH1 gene mutations in incomplete HNPCC families.

Hereditary non-polyposis colon cancer (HNPCC) is a common hereditary disease characterized by a predisposition to an early onset of colorectal cancer. The majority of the HNPCC families carry germline mutations of either hMSH2 or hMLH1 genes, whereas germline mutations of hPMS1 and hPMS2 genes have rarely been observed. Almost all of the germline mutations reported so far concern typical HNPCC families. However, there are families that display aggregations of colon cancer even though they do not fulfil all HNPCC criteria (incomplete HNPCC families) as well as sporadic cases of early onset colon cancers that could be related to germline mutations of these genes. Therefore, we screened germline mutations of hMSH2 and hMLH1 genes in 3 groups of patients from France and Turkey: typical HNPCC (n = 3), incomplete HNPCC (n = 9) and young patients without apparent familial history (n = 7). By in vitro synthesis of protein assay, heteroduplex analysis and direct genomic sequencing, we identified 1 family with hMSH2 mutation and 5 families with hMLH1 mutations. Two of the 3 HNPCC families (66%) displayed hMLH1 germline mutations. Interestingly, 4 of 9 families with incomplete HNPCC (44%) also displayed mutations of hMSH2 or hMLH1 genes. In contrast, no germline mutation of these genes was found in 7 young patients. Our results show that germline mutations of hMSH2 and hMLH1 genes contribute to a significant fraction of familial predisposition to colon cancer cases that do not fulfil all diagnostic criteria of HNPCC.

Adaptor Proteins, Signal Transducing↗
PubMed1997

Screening for neuroblastoma in France: methodological aspects and preliminary observations.

A pilot study of neuroblastoma mass screening was initiated in January 1990 in the Rhône French district. The expected number of births per year is 26,000. The study is designed for a 5-year period with three major goals: 1) measurement of the compliance rate of a voluntary test at 4 months of age; 2) evaluation of the technical value of high-pressure liquid chromatography (HPLC) as a screening method; and 3) detailed biological characterization of all detected tumors. 61,551 children were screened between May 1, 1990 and December 31, 1993. Participation was 69% in 1990, 81.5% in 1991, and over 83% in 1992. HPLC was a satisfactory assay method. The number of clinical examinations required for positive tests as defined in the protocol is 1 per 3,621 tests. The false positive rate is 1 per 3,583 tests. Eight neuroblastomas were discovered by-screening (one stage I, three stage II, one stage III, three stage IVs). All are alive and well but were good prognosis cases according to the main prognostic factors. Five patients were discovered before screening (so called Halo effect): one stage I, one stage III, three stage IVs. One died of disease and four are alive in complete remission after treatment. Two patients were false negative (one stage III with N-myc amplification, one stage IV with bad prognosis features) and three cases of neuroblastoma were missed because of noncompliance with the screening program. This pilot study concludes on the feasibility of a mass screening program in France. The estimated cumulative incidence of neuroblastoma at 3 years is 1 per 4,375 living births and overdiagnosis is probable. All the detected cases were of good prognosis and the false negative ones were poor prognosis cases.

Child, Preschool↗
PubMed1997

Clinical relevance of CD44 cell surface expression and MYCN gene amplification in neuroblastoma.

This multicentric analysis of tumours obtained from 140 patients with neuroblastoma confirms that the lack of CD44 expression is a highly significant factor of poor prognosis and, as previously published in multivariate analysis of the four factors, i.e. MYCN amplification, CD44 expression, age and tumour stage, CD44 expression and tumour stage were the only independent prognostic factors of event-free survival (Combaret et al., J Clin Oncol 1996, 14, 25-34). Furthermore, CD44 analysis affords significant prognostic discrimination in subgroups of patients with or without MYCN amplified tumours, both in low-stage neuroblastomas and high-grade neuroblastomas. In the subgroup of patients with low-stage neuroblastoma and the stage 4 subgroup, CD44 was the only independent prognostic factor for the prediction of event-free survival in a multivariate analysis. In conclusion, CD44 is one of the most powerful factors for predicting clinical outcome in neuroblastoma at the time of initial staging.

Age Factors↗
PubMed1997

1070 myeloablative megatherapy procedures followed by stem cell rescue for neuroblastoma: 17 years of European experience and conclusions. European Group for Blood and Marrow Transplant Registry Solid Tumour Working Party.

1070 myeloablative procedures followed by stem cell rescue for neuroblastoma are reviewed. These 1070 procedures are part of the European Group for Blood and Marrow Transplant (EBMTG) registry from the last 17 years (in 4536 patients). In 1070 neuroblastoma patients, survival at 2 years was 49%, at 5 years, 33% and relapses were observed as late as 7 years post-BMT (bone marrow transplant). However, 5-year survivors after megatherapy with BMT for stage 4 disease do have an 80% chance of becoming a long-term survivor. When BMT had been used in first complete response (CR1) no salvage was possible, whereas 15% survivors may be seen if BMT is used for the first time at relapse. Infants with stage 4 neuroblastoma had a 17% toxic death rate and indication in this group is exceptional and not recommended. In a matched cohort (17 allogeneic and 34 autologous), autologous stem cell rescue (SCR) was shown to be at least equal to allogeneic SCR. Multivariate analysis of clinical prognostic factors in children with stage 4 disease over 1 year showed that event-free survival was mainly influenced by two adverse factors before the megatherapy procedure: persisting skeleton lesions (99Tc and/or mIBG scan positive) as well as persisting bone marrow (BM) involvement.

Adolescent↗
PubMed1997

Clinical relevance of TRKA expression on neuroblastoma: comparison with N-MYC amplification and CD44 expression.

TRKA expression was evaluated on 122 untreated neuroblastomas by immunohistochemistry using an antibody with predetermined specificity. This procedure is simple and reliable for protein detection at cellular level in a routine clinical setting. Fourteen tumours were classified as benign ganglioneuroma with a restricted expression of TRKA on ganglion cells; these patients were excluded from the following analysis. A total of 108 tumours were classified as neuroblastoma or ganglioneuroblastoma; 74 expressed TRKA protein, which strongly correlated with low stage, absence of N-MYC amplification, age (<1 year), CD44 expression and favourable clinical outcome. In a univariate analysis including tumour stage, age, histology, N-MYC amplification, CD44 and TRKA expression, all parameters had significant prognostic value. The absence of TRKA expression on CD44-positive or N-MYC non-amplified tumours permits the characterization of a subgroup of patients with intermediate prognosis. However, in a multivariate analysis taking into consideration the prognostic factors mentioned above, CD44 and tumour stage were the only independent prognostic factors for the prediction of patients' event-free survival.

Analysis of Variance↗
PubMed1997

Correlation between clinical response to interleukin 2 and HLA phenotypes in patients with metastatic renal cell carcinoma.

HLA phenotypes were characterized for 79 patients with metastatic renal cell carcinoma treated with interleukin 2 (IL-2). HLA-A32 was associated with a clinical response (P = 0.025). The frequency of HLA-A3 and/or A32 was higher among responders than non-responders (P = 0.008). Thus, these results suggest that, in vivo, IL-2 may enhance cellular-mediated immunity against a tumour antigen and that some MHC molecules are more efficient than others for endogenous tumour antigen presentation.

Adult↗
PubMed1997

Response rate accuracy in oncology trials: reasons for interobserver variability. Groupe Français d'Immunothérapie of the Fédération Nationale des Centres de Lutte Contre le Cancer.

PURPOSE: We evaluated the impact of an evaluation committee (EC) on patients' overall response status in a large multicenter trial in oncology. We identified reasons for disagreements between investigators and the EC. MATERIALS AND METHODS: The Cancer Renal Cytokine (CRECY) study was a French multicenter trial that tested cytokine therapy in 489 patients with metastatic renal cell carcinoma. Objective response (OR) evaluation included medical imaging and was studied according to international guidelines. A blinded peer review of all responders and litigious cases was performed by an EC. RESULTS: Major disagreements occurred in 40% and minor disagreements in 10.5% of the reviewed files. The number of significant tumor responses was reduced by 23.2% after review by the EC. Reasons for disagreements included errors in tumor measurements, errors in selection of measurable targets, intercurrent diseases, and radiologic technical problems. These reasons for disagreements are analyzed and discussed. CONCLUSION: We conclude that all therapeutic trial results should be reviewed by peer analysis of all presumed responders by an EC. International guidelines for response evaluation should be updated by including more reliable methods of measurements and definition of minimal imaging procedures.

Clinical Trials as Topic↗
PubMed1996

A 5-year (1990-1994) neuroblastoma screening feasibility study in France. Methodology and preliminary observations.

INTRODUCTION: Following the pioneering Japanese experience, several European and North American groups implemented pilot studies on screening infants for neuroblastoma, considering the possibility of demonstrating a decrease in mortality rate. In France, a 5-year (1990-1994) feasibility study on neuroblastoma screening at the age of 4 months was initiated in the Rhône district (1.5 M inhabitants, 26,000 births per year). METHODS: Vanillylmandelic (VMA) and homovanillic (HVA) acids were measured by HPLC, and creatinine (Cr) by the Jaffé's kinetic method on Technicon RA-XT. VMA and HVA were expressed as microgram/mg of Cr. The method was assessed with both a daily intra-laboratory control and a sample of urine obtained from a national quality control organism. RESULTS AND DISCUSSION: The overall participation rate for the 5-year period was 82.2%. Out of 105,293 infants tested from 128,126 births, 12 NB cases were discovered with screening (screened cases) and 1 case was discovered with a late performed test (at 13 months of age). Six neuroblastomas were found clinically before the age of 4 m. Two cases were missed because the parents did not perform the test. Three children with normal tests at screening were false-negative cases: two of them were found secreting at diagnosis, while one remained non-secretory at diagnosis and later on. Otherwise, thirty-five false-positive tests were found. Biochemical observations are discussed. It is too early to reach clinical conclusions from this screening program on neuroblastomas as it is presently being followed up.

Chromatography, High Pressure Liquid↗