Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Sophie Dalac is active.

Publication


Featured researches published by Sophie Dalac.


American Journal of Clinical Pathology | 2005

Blastic NK-cell lymphomas (agranular CD4+CD56+ hematodermic neoplasms): a review.

Tony Petrella; Martine Bagot; Rein Willemze; M. Beylot-Barry; Béatrice Vergier; Michèle Delaunay; Chris J. L. M. Meijer; Philippe Courville; Pascal Joly; F. Grange; Anne de Muret; L. Machet; Anne Dompmartin; Jacques Bosq; Anne Durlach; Philippe Bernard; Sophie Dalac; Pierre Dechelotte; M. D’Incan; Janine Wechsler; Michael A. Teitell

Blastic natural killer (NK) cell lymphoma (also termed CD4+CD56+ hematodermic neoplasm) is a recently described entity, with the first case reported in 1994. It was suggested initially that the disease originates from NK cells. Since 1994, single cases and a few small series have been published. In this review, data from the literature and a series of 30 cases from the French and Dutch study groups on cutaneous lymphomas are discussed. The major clinical, histopathologic, and phenotypic aspects of the disease and diagnostic criteria and data suggesting a plasmacytoid dendritic cell origin for the tumor cells are provided.


The American Journal of Surgical Pathology | 2002

'Agranular CD4+ CD56+ hematodermic neoplasm' (blastic NK-cell lymphoma) originates from a population of CD56+ precursor cells related to plasmacytoid monocytes

Tony Petrella; Michael R. Comeau; Marc Maynadié; Gérard Couillault; Anne de Muret; Charles R. Maliszewski; Sophie Dalac; Anne Durlach; Laurent J. Galibert

In 1999, we reported seven cases of an unusual hematologic malignancy with primary cutaneous presentation that appeared as a distinct clinicopathologic entity characterized by medium-sized tumor cells with a peculiar CD3− CD4+ CD56+ CD43+ HLA-DR+ cell surface phenotype. Because the origin of tumor cells was not clear and they exhibited a nonlineage-specific phenotype, we hypothesized that such tumors likely originated from hematologic–myeloid precursor cells and were tentatively assigned the designation “agranular CD4+ CD56+ hematodermic neoplasms.” In the present study we report 14 cases (seven already reported and seven additional cases) of these tumors, and simultaneously we present now a rare population of cells that we have identified in the peripheral blood of healthy volunteers treated with Flt3 ligand. These cells express all the characteristic markers of CD4+ CD56+ hematodermic neoplasms. This population appears to be related to plasmacytoid monocytes because they also expressed CD68 and bright levels of CD123. To confirm the relationship between these normal cells and CD4+ CD56+ hematodermic neoplasms, we conducted an extensive comparative phenotypic study. Results show that these two cell types are indeed related because they share many phenotypic features, including the presence of CD4, CD56, CD43, CD68, and HLA-DR and the absence of other T, B, NK, or myelomonocytic markers. More importantly, we found that the bright expression of CD123 by immunohistochemistry is a distinctive characteristic of CD4+ CD56+ hematodermic neoplasms because all (n = 14) cases expressed this marker, whereas only two specimens in a control panel comprising 30 samples of related tumors expressed comparable levels of CD123. We therefore propose that oncogenic transformation of NCAM-expressing plasmacytoid monocyte-like cells may lead to “agranular CD4+ CD56+ hematodermic neoplasm.”


The American Journal of Surgical Pathology | 1999

CD4+ CD56+ cutaneous neoplasms : A distinct hematological entity ?

Tony Petrella; Sophie Dalac; Marc Maynadié; Francine Mugneret; Elisabeth Thomine; Philippe Courville; Pascal Joly; Bernard Lenormand; Laurent Arnould; Janine Wechsler; Martine Bagot; Claire Rieux; Jacques Bosq; Marie-Françoise Avril; Alain Bernheim; Thierry Molina; Alain Devidas; Marie-Hélène Delfau-Larue; Philippe Gaulard; Lambert D

We report seven cases of particular cutaneous tumors selected from the register of the French Study Group on Cutaneous Lymphomas. The patients (three men, four women) were aged 37-86 years. They initially presented with cutaneous nodules or papules. Three cases presented with regional lymph nodes. Stagings were negative, except for one patient with bone marrow involvement. Histological features were relevant with pleomorphic medium T-cell lymphoma, but these cells exhibited a distinguishing phenotype. They were positive for CD4, CD56, and also CD45, CD43, and HLA-DR. All other T-cell and B-cell markers were negative. The myelomonocytic markers (CD13, CD14, CD15, CD33, CD117, myeloperoxidase, and lysozyme) were negative excepted CD68, which was clearly positive in four cases and weakly in two cases. Others natural killer cell markers (CD16, CD57, TiA1, granzyme B), TdT, and CD34 were negative. Polymerase chain reaction studies did not detect any B or T clonal rearrangement. The cytogenetic studies, performed in five cases, showed a del(5q) in two cases. All patients were treated successfully by polychemotherapy, but relapsed quickly in the skin, between 4 and 28 months. Five patients developed bone marrow involvement, with leukemia in three cases, and they died in 5-27 months. One patient died at 17 months with skin progression. The seventh patient is alive at 33 months, with cutaneous progression. The origin of these cells is unclear. Despite expression of CD4 or CD56, we failed to demonstrate a T-cell, natural killer cell origin. However, CD4 and CD56 are not specific for T or natural killer lineages. Although these two markers are also known to be expressed by monocytic cells, classic myeloid antigens were negative. These seven cases, together with other rare similar cases already reported, seem to represent a distinct entity likely developed from hematological precursor cells.


International Journal of Cancer | 2000

Delays in diagnosis and melanoma prognosis (I): The role of patients

Marie Aleth Richard; Jean Jacques Grob; Marie Françoise Avril; Michèle Delaunay; Johany Gouvernet; Pierre Wolkenstein; Pierre Souteyrand; Brigitte Dreno; Jean Jacques Bonerandi; Sophie Dalac; L. Machet; Jean Claude Guillaume; J. Chevrant-Breton; Catherine Vilmer; F. Aubin; Bernard Guillot; M. Beylot-Barry; C. Lok; Nadia Raison-Peyron; Philippe Chemaly

A prospective survey was conducted to assess the role of patients in the melanoma prognosis. Consecutive patients with primary melanoma were interviewed and examined using a comprehensive questionnaire including a psychological instrument. Main outcome measures were the delay before medical intervention and the tumor thickness. Of 590 melanomas, 70.8% were detected by patients and this proportion was higher in females. Relatives were involved in the detection of half of the cases. Median delays before the patient realized he had a suspicious lesion, before this lesion was seen by a doctor, and before the melanoma was removed were 4 months, 2 months, and 1 week, respectively. Delays up to several years were observed in some cases. The rate of self‐detection tended to be lower, the delays before seeking medical advice to be longer, and the tumor thickness to be higher in old people, in males, in lower‐educated individuals, in those living out of towns, and in people with a low awareness about melanocytic tumors than in other cases. Conversely, individuals with a high number of atypical nevi, those who were aware to be at risk, and those who regularly visited a dermatologist tended to detect their melanoma more rapidly. No specific psychological traits were associated with a late reaction, although negligence and anxiety tended to prolong the delays. Knowledge about melanoma was poor in many patients, especially in males, and wrong beliefs were widespread. This study provides the targets of future education programs. Int. J. Cancer 89:271–279, 2000.


American Journal of Clinical Pathology | 2004

TCL1 and CLA Expression in Agranular CD4/CD56 Hematodermic Neoplasms (Blastic NK-Cell Lymphomas) and Leukemia Cutis

Tony Petrella; Chris J. L. M. Meijer; Sophie Dalac; Rein Willemze; Marc Maynadié; L. Machet; Olivier Casasnovas; Béatrice Vergier; Michael A. Teitell

Agranular CD4/CD56 hematodermic neoplasm (CD4/CD56 HN), also termed blastic natural killer cell lymphoma, is characterized by a peculiar immunophenotype and high skin tropism. The lineage of origin is not known, and a plasmacytoid dendritic cell derivation has been proposed. CD4/CD56 HN generally is diagnosed by using tumor skin biopsy, with the most important differential diagnosis being myelomonocytic leukemia cutis. We evaluated the expression of 2 plasmacytoid dendritic cell antigens, T-cell leukemia 1 (TCL1) and cutaneous lymphocyte-associated antigen (CLA), in 29 cases of CD4/CD56 HN and 18 cases of myelomonocytic leukemia cutis. TCL1 and CLA were expressed in 26 (90%) of 29 CD4/CD56 HN cases vs TCL1 expression in 3 (17%) and CLA expression in 14 (78%) of 18 leukemia cutis cases. Furthermore, CLA antiserum displays a peculiar small-dot staining pattern in CD4/CD56 HN. These results suggest that TCL1 and CLA are good markers for CD4/CD56 HN tumor cells and add support for a plasmacytoid dendritic cell origin. The high skin tropism of CD4/CD56 HN might be related to the skin-homing property of CLA.


The American Journal of Surgical Pathology | 1998

Statistical evaluation of diagnostic and prognostic features of CD30+ cutaneous lymphoproliferative disorders : A clinicopathologic study of 65 cases

Béatrice Vergier; M. Beylot-Barry; K. Pulford; P. Michel; Jacques Bosq; A. De Muret; Claire Beylot; Michèle Delaunay; Mf Avril; Sophie Dalac; C. Bodemer; Pascal Joly; Alexis Groppi; A. De Mascarel; Martine Bagot; Dy Mason; Janine Wechsler; Jean Philippe Merlio

Several clinical and histopathologic features of 65 CD30+ cutaneous lymphoproliferations were evaluated for their diagnostic value between CD30+ primary versus secondary cutaneous lymphomas and for their prognostic significance. Primary cutaneous disease, spontaneous regression, and absence of extracutaneous spreading (but not age < or =60 years) were associated with a better prognosis. Epithelial membrane antigen, BNH9, CD15 or CBF.78 antigen were expressed in all types of cutaneous lymphoproliferations. However, epithelial membrane antigen immunoreactivity was more frequently expressed in CD30+ secondary cutaneous large-cell lymphoma. Among CD30+ primary cutaneous large-cell lymphoma, CD15 expression was only seen in localized skin lesions. P53 expression was not associated with spontaneous regression, extracutaneous spreading, or survival. Nested reverse transcriptase-polymerase chain reaction allowed the detection of NPM-ALK transcripts in 10 of 26 CD30+ primary and in 3 of 11 secondary cutaneous large-cell lymphomas. The ALK protein was detected in only 1 of 50 primary and in 4 of 15 secondary cutaneous CD30+ lymphoproliferations. In CD30+ primary cutaneous lymphoproliferation, NPM-ALK transcripts might be expressed by very rare normal or tumoral cells that are undetectable by immunohistochemistry. However, the expression of either NPM-ALK transcripts or ALK-protein was not correlated with prognosis or age in CD30+ cutaneous lymphoproliferations.


International Journal of Cancer | 2000

Delays in diagnosis and melanoma prognosis (II): The role of doctors

Marie Aleth Richard; Jean Jacques Grob; Marie Françoise Avril; Michèle Delaunay; Johany Gouvernet; Pierre Wolkenstein; Pierre Souteyrand; Brigitte Dreno; Jean Jacques Bonerandi; Sophie Dalac; L. Machet; Jean Claude Guillaume; J. Chevrant-Breton; Catherine Vilmer; F. Aubin; Bernard Guillot; M. Beylot-Barry; C. Lok; Nadia Raison-Peyron; Philippe Chemaly

A prospective survey was conducted to assess physician responsibility in melanoma prognosis. Consecutive patients with primary melanoma were interviewed and examined using a standardized questionnaire. Main outcome measures were medical components of the delay before tumor resection and tumor thickness. Of 590 melanomas, 29.1% were coincidentally detected by physicians and their tumor depth was lower than in melanomas detected by patients (p < 0.001). Physician sensitivity for melanoma diagnosis was evaluated at 86%. Median time intervals to propose resection and to perform removal of melanoma were short: 0 (mean 103) and 7 (mean 68) days, respectively. Melanomas were managed in an inappropriate way in 14.2% of cases. Location on acral areas and absence of pigmentation were associated with longer medical delays and more frequent inappropriate medical attitudes. Melanomas located on hardly visible areas were less frequently detected by physicians than those on visible areas. Medical delays were shorter, doctors attitude was more frequently appropriate, and melanoma thickness was lower (p < 0.001) when the patient visited a dermatologist (54.7%) than when he or she visited a general practitioner (33.4%). Our study shows that doctor responsibility accounts for only a small part of the total delay before melanoma removal. However, systematic total examination and better training of doctors, especially about unusual forms of melanoma, could still improve melanoma detection. Int. J. Cancer 89:280–285, 2000.


The Journal of Infectious Diseases | 2002

Prognostic Value of Quantitative Kaposi Sarcoma–Associated Herpesvirus Load in Posttransplantation Kaposi Sarcoma

Claire Pellet; Sylvie Chevret; Camille Frances; Sylvie Euvrard; Mylène Hurault; Christophe Legendre; Sophie Dalac; Dominique Farge; Corinne Antoine; Christian Hiesse; Marie-Noelle Peraldi; Philippe Lang; Didier Samuel; Yvon Calmus; Félix Agbalika; P. Morel; Fabien Calvo; Celeste Lebbe

Organ transplant recipients have a higher risk of Kaposi sarcoma (KS). A quantitative real-time polymerase chain reaction assay was developed to evaluate KS-associated herpesvirus (KSHV) as a prognostic tool in transplant recipients with KS. Forty-three patients who developed KS after transplantation were included in a cross-sectional study to correlate virus load with transplantation or KS parameters. Seventeen patients (40%) had KSHV viremia (>100 copies/microg of DNA; median, 6067 copies/microg of DNA). Factors associated with these levels of viremia by univariate analysis were progression of KS (P=.00002), time from KS diagnosis (P=.0007), actual stage of KS (P=.006), initial stage of KS (P=.22), graft loss (P=.013), and time from transplantation (P=.0246). Disease progression remained associated with KSHV viremia in a multivariate analysis (P=.01). Thus, quantification of KSHV load in peripheral blood mononuclear cells could represent a useful tool for monitoring transplant recipients with KS.


The Journal of Pathology | 1998

Value of clonality studies of cutaneous T lymphocytes in the diagnosis and follow-up of patients with mycosis fungoides

Marie-Hélène Delfau-Larue; Tony Petrella; Chantal Lahet; Christelle Lebozec; Martine Bagot; F. Roudot-Thoraval; Sophie Dalac; Jean-Pierre Farcet; Janine Wechsler

Histological features of early mycosis fungoides (MF) can simulate numerous inflammatory lesions and histological confirmation of MF is often delayed, compared with clinical diagnosis. Recently, using molecular techniques, the detection of a dominant T‐lymphocyte clone has been reported in cutaneous lesions of MF. The aim of the present study was to determine the diagnostic value of a dominant T‐lymphocyte clone as assessed by PCR‐DGGE in early MF. Histopathological and molecular analyses were performed on cutaneous lesions from 104 patients clinically suspected as having MF. In this population, the positive predictive value of a PCRγ(+) was 0·86. In addition, four of six patients whose lesions were PCRγ(+) (detectable dominant T‐cell clone) but not histologically MF progressed to MF within 2–48 months. In order to evaluate the relevance of PCRγ–DGGE in MF follow‐up, serial biopsies were performed in 24 patients. In 89 per cent of cases, the presence or absence of a PCRγ(+) was constant during the course of the disease. When present, the DGGE imprint of PCR products was case‐specific. These data demonstrate the diagnostic value in MF of T‐lymphocyte clonality assessed by PCRγ–DGGE on cutaneous lesions and show that the technique can be used in MF follow‐up to evaluate residual disease with high specificity.


American Journal of Clinical Pathology | 2011

Histologic and Immunohistologic Characterization of Skin Localization of Myeloid Disorders

Claire Bénet; Aurélie Gomez; Claire Aguilar; Claire Delattre; Béatrice Vergier; M. Beylot-Barry; Sylvie Fraitag; A. Carlotti; Pierre Déchelotte; M. D’Incan; Valérie Costes; Olivier Dereure; Nicolas Ortonne; Martine Bagot; Liliane Laroche; Astrid Blom; Sophie Dalac; Tony Petrella

A retrospective analysis of 173 skin biopsy specimens of myeloid leukemia cutis (MLC) was performed to determine histologic and immunophenotypic criteria that could distinguish the varied myeloid disorders from one another. For the study, 11 relevant histologic items were scored and 12 antigens were studied (CD68 [KP1], CD163, CD14, CD4, myeloperoxidase [MPO], CD33, CD117, CD34, CD56, MIB-1, CD303, and CD123). Underlying myeloid disorders were essentially acute myeloid leukemias (65.3%), chronic myelomonocytic leukemias (11.0%), and refractory anemia (10.4%). Skin lesions were de novo in 7.5%, concurrent in 26.6%, and subsequent in 60.7%. Several morphologic characteristics (density, size of tumor cells, inflammatory background) were statistically useful in distinguishing between varied myeloid disorders. De novo MLCs displayed a specific morphologic profile. Association of CD68, CD33, and MPO could diagnose 100% of the cases of MLC. However, the immunohistochemical panel could not distinguish between the varied underlying myeloid disorders, with the exception that CD123 was particularly powerful in recognizing chronic myelomonocytic leukemia and also permitted reclassification of 4 cases as blastic plasmacytoid dendritic cell neoplasm.

Collaboration


Dive into the Sophie Dalac's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Bernard Guillot

University of Montpellier

View shared research outputs
Top Co-Authors

Avatar

F. Aubin

University of Franche-Comté

View shared research outputs
Top Co-Authors

Avatar

Tony Petrella

Hôpital Maisonneuve-Rosemont

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

L. Machet

French Institute of Health and Medical Research

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge