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Dive into the research topics where Yves Chretien is active.

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Featured researches published by Yves Chretien.


Journal of Clinical Oncology | 1993

Combined radiation and chemotherapy for invasive transitional-cell carcinoma of the bladder: a prospective study

Martin Housset; C. Maulard; Yves Chretien; Bertrand Dufour; S. Delanian; Judith Huart; Francoise Colardelle; Pascale Brunel; François Baillet

PURPOSE To improve the results obtained by cystectomy alone and to determine the possibilities of conservative treatment in invasive bladder cancer, we designed a prospective study using a combination of fluorouracil (5-FU) plus cisplatin and concomitant radiation therapy, followed by either cystectomy or additional chemoradiotherapy. PATIENTS AND METHODS Fifty-four patients with stage T2 to T4 operable untreated invasive bladder cancer were entered onto the study. Treatment was begun in all patients by transurethral resection (TUR) and followed by the 5-FU-cisplatin combination with concomitant bifractionated split-course radiation therapy. A control cystoscopy was performed 6 weeks after completion of the neoadjuvant program. Patients with persistent tumor underwent cystectomy. Complete responders were treated by either additional chemoradiotherapy (group A) or cystectomy (group B). RESULTS At control cystoscopy, 40 of 54 patients (74%) had a histologically documented complete response. Four responders developed recurrent pelvic disease after a mean follow-up time of 27 +/- 12 months (three in group A and one in group B). Metastatic disease, which developed in 16 patients, occurred more frequently in the nonresponders (71%) than in responders (15%). The disease-free survival rate at 3 years was 62%; it was significantly better in responders (77%) than in nonresponders (23%). There was no difference in survival between groups A and B. CONCLUSION This neoadjuvant chemoradiotherapy combination, easy to implement and well tolerated even in elderly patients, provides a high complete response rate. It may prove to be effective in inoperable patients and may be proposed as conservative treatment in patients with a complete response to the initial course of chemoradiation.


Nature | 2010

Functionally defective germline variants of sialic acid acetylesterase in autoimmunity

Ira Surolia; Stephan P. Pirnie; Vasant Chellappa; Kendra N. Taylor; Annaiah Cariappa; Jesse Moya; Haoyuan Liu; Daphne W. Bell; David R. Driscoll; Sven Diederichs; Khaleda Haider; Ilka Arun Netravali; Sheila Le; Roberto Elia; Ethan Dow; Annette Lee; Jan Freudenberg; Philip L. De Jager; Yves Chretien; Ajit Varki; Marcy E. MacDonald; Tammy Gillis; Timothy W. Behrens; Donald B. Bloch; Deborah S. Collier; Joshua R. Korzenik; Daniel K. Podolsky; David A. Hafler; Mandakolathur R. Murali; Bruce E. Sands

Sialic acid acetylesterase (SIAE) is an enzyme that negatively regulates B lymphocyte antigen receptor signalling and is required for the maintenance of immunological tolerance in mice. Heterozygous loss-of-function germline rare variants and a homozygous defective polymorphic variant of SIAE were identified in 24/923 subjects of European origin with relatively common autoimmune disorders and in 2/648 controls of European origin. All heterozygous loss-of-function SIAE mutations tested were capable of functioning in a dominant negative manner. A homozygous secretion-defective polymorphic variant of SIAE was catalytically active, lacked the ability to function in a dominant negative manner, and was seen in eight autoimmune subjects but in no control subjects. The odds ratio for inheriting defective SIAE alleles was 8.6 in all autoimmune subjects, 8.3 in subjects with rheumatoid arthritis, and 7.9 in subjects with type I diabetes. Functionally defective SIAE rare and polymorphic variants represent a strong genetic link to susceptibility in relatively common human autoimmune disorders.


Human Mutation | 1999

Mutations of the VHL gene in sporadic renal cell carcinoma: Definition of a risk factor for VHL patients to develop an RCC

Catherine Gallou; Dominique Joly; Arnaud Mejean; F. Staroz; Natacha Martin; G. Tarlet; M.T. Orfanelli; Raymonde Bouvier; Dominique Droz; Yves Chretien; J.M. Maréchal; Stéphane Richard; Claudine Junien; Christophe Béroud

To investigate the nature of somatic von Hippel‐Lindau (VHL) mutations, we analyzed 173 primary sporadic human renal cell carcinomas for mutations of the VHL tumor suppressor gene, using polymerase chain reaction (PCR) and single‐strand conformational polymorphism analysis (SSCP) of DNA. We detected abnormal SSCP pattern in 73 samples. After sequencing, we identified microdeletions in 58% of cases, microinsertions in 17%, nonsense mutations in 8%, and missense mutations in 17%. Among these mutations, 50% correspond to new mutations. VHL mutations were found only in the nonpapillary renal cell carcinoma (RCC) subtype, as previously reported. To compare somatic and germline mutations, we used the VHL database, which includes 507 mutations. The study of mutational events revealed a significant difference between somatic and germline mutations with mutations leading to truncated proteins observed in 78% of somatic mutations vs only 37% in germline mutations (P < 0.001). We postulated that a specific pattern of VHL mutations is associated with sporadic RCC. This pattern corresponds to mutations leading mainly to truncated proteins with few specific missense mutations. We then analyzed the occurrence of RCC in VHL families, based on the nature of mutations. We observed RCC in at least one member of the VHL families in 77% of cases with mutations leading to truncated proteins versus 55% in cases with missense mutations (P < 0.05). Thus, mutations resulting in truncated proteins may lead to a higher risk of RCC in VHL patients. Hum Mutat 13:464–475, 1999.


Urology | 1997

COLOR DOPPLER-GUIDED PROSTATE BIOPSIES IN 591 PATIENTS WITH AN ELEVATED SERUM PSA LEVEL: IMPACT ON GLEASON SCORE FOR NONPALPABLE LESIONS

F. Cornud; X. Belin; D. Piron; Yves Chretien; T. Flam; Jean-Michel Casanova; O. Hélénon; Arnaud Mejean; Nicolas Thiounn; Jean-François Moreau

OBJECTIVES To compare results of color Doppler-guided ultrasonography (CDUS) versus those of systematic biopsies in 591 patients with an elevated serum PSA level and to correlate them with digital rectal examination (DRE) findings. METHODS Biopsies were directed into hypervascularized (CDUS+) or hypovascularized (CDUS-) hypoechoic peripheral zone nodules (443 cases). When transrectal ultrasound (TRUS) was normal (148 cases), biopsies were directed into hypervascular area. Six additional posterior biopsies were also performed in every patient, together with four anterior biopsies in 117 patients with normal DRE and prostate weight above 40 g. RESULTS Biopsies were positive in 339 patients (57%). Positive biopsy rate (PBR) of directed biopsies was 84% in hypervascular abnormalities (264 of 316) and 17% in hypovascular nodules (23 of 134) (P < 0.001). PBR of combined biopsies was 84% in CDUS+ patients (266 of 316) and 26% in CDUS- patients (73 of 275) (P < 0.001). Comparison of TRUS and CDUS showed a sensitivity of 0.9 and 0.78, respectively, and a specificity of 0.46 and 0.8, respectively. Of the 131 patients with a PSA level between 4 and 10 ng/mL and a normal DRE, PBR was 59% (22 of 37) when CDUS was positive and 11% (10 of 94) when it was negative, regardless of TRUS abnormalities (P < 0.001). Nonpalpable cancers with a negative CDUS showed a significantly (P < 0.001) lower Gleason score (5.5 +/- 0.9) than that of CDUS+ cancer (6.5 +/- 1.1). Eleven cancers were diagnosed by only anterior positive biopsies. All of them had a negative CDUS and a PSA level above 10 ng/mL. CONCLUSIONS CDUS does not modify prostate biopsy policy except in patients with negative CDUS, normal DRE, and PSA level between 4 and 10 ng/mL, where deferment of biopsy can be advocated. Anterior biopsies are only useful in patients with a PSA level above 10 ng/mL and a negative CDUS.


The Journal of Urology | 2000

Detection of circulating prostate derived cells in patients with prostate adenocarcinoma is an independent risk factor for tumor recurrence.

Arnaud Mejean; Giovanna Vona; Bertrand Nalpas; Diane Damotte; Nicole Brousse; Yves Chretien; Bernard Dufour; Bernard Lacour; Christian Brechot; Patrizia Paterlini-Bréchot

PURPOSE To determine whether the presence of prostate-derived cells in the peripheral blood circulation is a marker of prostate cancer and to define the clinical impact of the test. MATERIALS AND METHODS We tested the peripheral blood of 99 patients with prostate adenocarcinoma (PAC), 79 of them undergoing radical prostatectomy, and 92 controls (31 healthy volunteers, 50 patients with adenoma and 11 with prostatitis) using a highly controlled procedure including reverse-transcriptase polymerase chain reaction (RT-PCR) targeted to prostate-specific antigen (PSA) mRNA. Patients were followed for 26 +/- 12 (range: 4 to 49) months. Forty tumor tissues were analyzed by immunohistochemistry for expression of p53 and E-cadherin antigens. RESULTS Thirty three (33%) patients with PAC and 2 (2%) controls scored positive (p <0.0001) for the test. Detection of circulating prostatic cells was associated with development of metastases (p <0. 001), with relapse (p <0.001) and with a serum PSA level at diagnosis higher than 15 ng./ml. (p = 0.009). The rate of development of metastases according to time was significantly higher in patients who scored positive for the test (p <0.04). In a multivariate analysis, only the RT-PCR test was an independent risk factor associated with relapse (RR: 6.7). Finally, E-cadherin expression was significantly lower in the tumor tissues of positive patients as compared with those who scored negative for the test (p <0.01). CONCLUSIONS This RT-PCR procedure, performed at diagnosis and with appropriate controls, is a clinically useful assay in evaluating the risk of tumor recurrence after radical prostatectomy in patients with PAC.


Transplantation | 2000

HBV genotypic resistance to lamivudine in kidney recipients and hemodialyzed patients.

Hélène Fontaine; Valérie Thiers; Yves Chretien; Hervé Zylberberg; R. Poupon; Christian Bréchot; Christophe Legendre; Henri Kreis; Stanislas Pol

BACKGROUND Lamivudine is a potent inhibitor of human immunodeficiency virus reverse transcriptase and hepatitis B virus (HBV) DNA polymerase. Its overall efficiency is clearly hampered by relapse at discontinuation and by risk of genotypic resistance. We describe herein the first cases of HBV resistance to lamivudine in kidney recipients and hemodialyzed patients. METHODS We analyzed 26 HBV-infected kidney recipients and five hemodialyzed patients treated with lamivudine who became serum HBV DNA-negative (by Digene test). The biological and virological follow-up identified breakthrough as defined by the reappearance of serum HBV DNA. In two cases of breakthrough, HBV DNA was amplified and sequenced through the polymerase domain, including the YMDD motif, before the beginning of treatment and at time of breakthrough to determine genotypic mutations. RESULTS Ten breakthroughs (reappearance of serum HBV DNA) were observed after a median follow-up of 11 months in eight kidney recipients and two hemodialyzed patients after a median duration of treatment of 16.5 (from 4 to 31) months of treatment. Previous HBe/anti-HBe seroconversion was not observed in the patients who escaped. In two kidney recipients, the comparison of HBV-DNA sequences before the treatment and after the breakthrough identified in one case a mutation of the highly conserved YMDD motif (YVDD), whereas in the second case, no genotypic mutation was observed in the sequenced region. CONCLUSION We report the first cases of HBV genotypic resistance to lamivudine in kidney recipients and hemodialysis patients. Genotypic resistance is observed after 4-31 months of therapy. The YMDD mutation does not account for all cases of virological escape.


Journal of Clinical Oncology | 1998

Outpatient treatment with subcutaneous interleukin-2 and interferon alfa administration in combination with fluorouracil in patients with metastatic renal cell carcinoma: results of a sequential nonrandomized phase II study. Subcutaneous Administration Propeukin Program Cooperative Group.

Jean-Marc Tourani; C Pfister; J F Berdah; A Benhammouda; P Salze; A Monnier; B Paule; P Guillet; Yves Chretien; Y Brewer; M. Di Palma; Michel Untereiner; E Malaurie; Z Tadrist; Jean-Marc Pavlovitch; D Hauteville; Arnaud Mejean; M Azagury; D. Mayeur; Virginie Lucas; I. Krakowski; D Larregain-Fournier; H Abourachid; Jean-Marie Andrieu; C Chastang

PURPOSE We report the results of the Subcutaneous Administration Propeukin Program (SCAPP) II trial of an outpatient treatment in renal cell carcinoma using interleukin-2 (IL-2) and interferon alfa-2a (IFN-alpha) administered subcutaneously in combination with fluorouracil (5-FU). The objective of this multicenter trial was to confirm that the combination of IL-2, IFN-alpha, and 5-FU leads to a response rate greater than 20%. PATIENTS AND METHODS Patients with metastatic renal cell carcinoma were included in this study. During the induction phase of the treatment, which lasted 10 weeks, IL-2 and IFN-alpha were administered subcutaneously three times a week for 8 weeks at doses of 18 MIU and 9 MIU, respectively. During these 8 weeks, every Monday, 5-FU was administered at a dose of 750 mg by intravenous infusion over 30 minutes. After evaluation, responding patients or patients with stable disease (SD) were given maintenance treatment, until disease progression (PD) or the appearance of unacceptable toxicity. Each maintenance cycle consisted of a 2-week treatment followed by a three-week rest period. During treatment, IL-2 and IFN-alpha were administered subcutaneously three times a week at doses of 18 MIU and 9 MIU, respectively. Every Monday, 5-FU was administered at a dose of 750 mg by intravenous infusion over 30 minutes. RESULTS This trial was closed when the sixth sequential analysis showed the lack of benefit from this combination. At the end of the induction period, of 62 patients, 12 (19%; 95% confidence interval [CI], 10% to 31%) reached an objective response, including one complete response (CR), 16 presented with SD, and 27 showed PD. Twenty-seven patients (43%) developed severe toxicity that required reduction of the planned doses (13 patients), delayed treatment (eight patients), or treatment termination (six patients). Seventeen patients were given maintenance treatment. One- and 2-year survival rates were estimated at 55% and 33%, respectively. The 2-year survival rate was 15% in 11 patients who presented with three poor-prognosis factors and 41% in 51 patients who initially presented with no, one, or two poor-prognosis factors (P = .04). CONCLUSION As in other recently published studies that used 5-FU, IL-2, and IFN-alpha, the multicenter SCAPP II trial in patients with metastatic renal cell carcinoma generated severe toxicity. This sequential trial failed to confirm the favorable results previously obtained by Atzpodien and Sella with this combination of three drugs. Its efficacy, assessed on the response and survival rates, is near to the results observed in programs that used IL-2 alone given subcutaneously.


The Journal of Urology | 1996

Postoperative radiation therapy in 26 patients with invasive transitional cell carcinoma of the upper urinary tract : no impact on survival ?

C. Maulard-Durdux; Bertrand Dufour; C. Hennequin; Yves Chretien; B. Vignes; D. Droz; S. Delanian; Martin Housset

PURPOSE To evaluate the role of adjuvant radiation therapy in invasive transitional cell carcinoma of the upper urinary tract, we retrospectively reviewed a series of 26 patients who underwent radical surgery plus postoperative prophylactic irradiation for such a tumor. MATERIALS AND METHODS Between February 1980 and October 1993, 18 men and 8 women (mean age 65 +/- 9 years, standard deviation) were treated for an invasive transitional cell carcinoma of the upper urinary tract. Tumor location was the renal pelvis in 15 patients (58%). The tumor was pathological stage B in 11 patients (42%) and stage C in 15 (58%). Tumor grade was 2 in 10 patients, 3 in 15 and unknown in 1. One patient had epidermoid metaplasia of urothelial cancer and 9 had node involvement. All patients underwent surgery followed by radiation therapy to a total dose of 45 Gy. to the tumor bed (23) and/or regional nodes (18). RESULTS After a mean followup of 45 months 13 patients (50%) were alive and 11 were disease-free at analysis. Local tumor relapse, nodal recurrence and metastasis were noted in 1, 4 (15%) and 14 (54%) patients, respectively. All patients with nodal recurrence had metastasis. A secondary location was noted frequently (6 bladder, 1 contralateral renal pelvis and 1 urethral tumors). Overall 5-year survival rate and 5-year survival rate with no evidence of disease were 49% and 30%, respectively. Overall 5-year survival rates were 60% for stage B and 19% for stage C disease (p = 0.07), 49% for node-negative versus 15% for node-positive cancer (p = 0.04), and 90% for grade 2 and 0% for grade 3 tumors (p < 0.01). CONCLUSIONS In our trial using a radio-surgical approach, local control of disease and survival rates were similar to those reported previously in surgical series. Prophylactic postoperative radiation therapy is not recommended except in prospective randomized studies.


Transplantation | 2004

Renal cell carcinoma of the grafted kidney: how to improve screening and graft tracking.

Morgan Rouprêt; Marie-Noelle Peraldi; Olivier Thaunat; Yves Chretien; Nicolas Thiounn; Bertrand Dufour; Henri Kreis; Arnaud Mejean

Renal cell carcinoma of transplanted kidneys is rare. We report three such cases among 1,250 kidney grafts that were performed or followed from 1968 to 2002. A strategy to diagnose these lesions is needed because of their rarity, late detection, and therapeutic repercussions. At the least, the strategy should include annual ultrasonography of the graft throughout its lifespan. Because the risk of tumor development in another organ from the same donor is not negligible, a national registry should be established to rapidly alert graft recipients with the same donor and other transplantation centers about the risk of graft tumors.


European Urology | 1999

Mortality and Morbidity after Nephrectomy for Renal Cell Carcinoma Using a Transperitoneal Anterior Subcostal Incision

Arnaud Mejean; Benoit Vogt; Jean Emile Quazza; Yves Chretien; Bertrand Dufour

Objectives: We have reviewed our surgical experience to document intra- and postoperative mortality and morbidity in 656 patients with renal cell carcinoma who underwent nephrectomy through a transperitoneal anterior subcostal incision (TASI). Materials and Methods: From 1986 to 1997 we performed 656 nephrectomies for renal cell carcinoma using a TASI. Details of the surgical procedure are presented together with a retrospective analysis of the postoperative data concerning both the patient and the complications related to this approach. Results: The mean time of operation was 130 min and the mean discharge from hospital 11 days. An additional surgical procedure in relation with the cancer facilitated by this approach was necessary in 2.1% of cases. The rates of intra- and postoperative complications were respectively 6.4 and 29.7%. The rate of intestinal complications was 1.8% and a splenic injury occurred in 8% of left nephrectomy. The mortality rate was 0.6%. Conclusions: The TASI is a large convenient incision which allows safe control of the renal pedicle in a very large number of renal tumors, even those located in the upper pole of the kidney. The rate of gut complications is very acceptable. Splenic injury is the major problem during left nephrectomy but careful dissection and surgical experience could decrease this complication, especially in case of upper pole renal tumor. We consider the TASI to be the main radical nephrectomy incision for renal cell carcinoma.

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Dive into the Yves Chretien's collaboration.

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Bertrand Dufour

Necker-Enfants Malades Hospital

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Arnaud Mejean

Paris Descartes University

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Nicolas Thiounn

Necker-Enfants Malades Hospital

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Jean-François Moreau

Necker-Enfants Malades Hospital

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F. Cornud

Paris Descartes University

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Olivier Hélénon

École pratique des hautes études

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Cornud F

Necker-Enfants Malades Hospital

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Hélénon O

Necker-Enfants Malades Hospital

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