Publications by authors named "Christine Lefebvre"

Background: MYC-driven lymphomas are a subset of B-cell lymphomas characterized by genetic alterations that dysregulate the expression of the MYC oncogene. When overexpressed, typically through chromosomal translocations, amplifications, or other mechanisms, MYC can drive uncontrolled cell growth and contribute to cancer development. MYC-driven lymphomas are described as aggressive entities which require intensive treatment approaches and can be associated with poor prognosis.

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Challenging behaviors in young children with autism and intellectual disabilities pose significant barriers to learning and inclusion. The Prevent-Teach-Reinforce for Young Children (PTR-YC) program is an evidence-based intervention that addresses these behaviors according to Positive Behavior Intervention Support principles. It is essential to assess the social validity of an intervention, when implemented into a public service system, to ensure sustainability and relevance to stakeholders.

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Background: Pediatric cancer is associated with stressors that increase the risk for distress across family members. Psychosocial support varies and may not meet family needs and preferences. This study investigated family members' points of view regarding psychosocial service needs, as a first step of a large participative research project aiming to develop interventions grounded in key stakeholders' perspectives.

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A newborn girl had typical "blueberry muffin" skin lesions, which shows histopathologic features of monocytic leukemia cutis. The systemic leukemia was demonstrated after one month of life. She was treated by chemotherapy, including induction and three consolidation cures, according to the ELAM02 protocol, which led to complete remission.

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Cytogenetic analysis is mandatory at initial assessment of B-cell acute lymphoblastic leukemia (B-ALL) due to its diagnostic and prognostic value. Results from chromosome banding analysis and complementary FISH are taken into account in therapeutic protocols and further completed by other techniques (RT-PCR, SNP-array, MLPA, NGS, OGM). Indeed, new genomic entities have been identified by NGS, mostly RNA sequencing, such as Ph-like ALL that can benefit from targeted therapy.

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Mature T-cell and natural killer (NK)-cell neoplasms (MTNKNs) are a highly heterogeneous group of lymphomas that represent 10-15 % of lymphoid neoplasms and have usually an aggressive behavior. Diagnosis can be challenging due to their overlapping clinical, histological and immunophenotypic features. Genetic data are not a routine component of the diagnostic algorithm for most MTNKNs.

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Genetic data are becoming increasingly essential in the management of hematological neoplasms as shown by two classifications published in 2022: the 5th edition of the World Health Organization Classification of Hematolymphoid Tumours and the International Consensus Classification of Myeloid Neoplasms and Acute Leukemias. Genetic data are particularly important for acute myeloid leukemias (AMLs) because their boundaries with myelodysplastic neoplasms seem to be gradually blurring. The first objective of this review is to present the latest updates on the most common cytogenetic abnormalities in AMLs while highlighting the pitfalls and difficulties that can be encountered in the event of cryptic or difficult-to-detect karyotype abnormalities.

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Molecular analysis is the hallmark of T-cell acute lymphoblastic leukemia (T-ALL) categorization. Several T-ALL sub-groups are well recognized based on the aberrant expression of specific transcription factors. This recently resulted in the implementation of eight provisional T-ALL entities into the novel 2022 International Consensus Classification, albeit not into the updated World Health Organization classification system.

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Myelodysplastic syndromes (MDS) are hematological malignancies classically defined by the presence of cytopenia(s) and dysmorphic myeloid cells. It is now known that MDS can be preceded by a pre-malignant condition called clonal cytopenia of unknown significance (CCUS), which associates a clonality marker with cytopenia in the absence of criteria of dysplasia. However, to date, it is not clear whether chromosomal abnormalities should be considered in the definition of CCUS or if they carry a prognostic impact in CCUS patients.

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Follicular lymphoid hyperplasia induced by dasatinib is an entity recently described. It is sometimes difficult to rule out the diagnostic of small B-cell lymphoma. Usually, the node is swollen, with follicular architecture conserved, composed by germinal centers with variable size and shape, with a hight number of mitoses and tingible bodies macrophages inside.

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Introduction: Suspicion of myelodysplastic syndromes (MDS) is the most common reason for bone marrow aspirate in elderly patients. Peripheral blood neutrophil myeloperoxidase expression quantified by flow cytometric analysis might rule out MDS for up to 35% of patients referred for suspected disease, without requiring bone marrow aspiration. Yet laboratory-developed liquid antibody cocktails have practical limitations, because of lack of standardisation and poor stability.

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Article Synopsis
  • - The text discusses the role of Plasmacytoid Dendritic Cells (pDC) in immune responses and identifies two major neoplastic conditions associated with them: Blastic pDC Neoplasm (BPDCN) and Mature pDC Proliferation (MPDCP), which includes pDC-CMML and pDC-AML.
  • - BPDCN is characterized by complex karyotypes, frequent genetic rearrangements, and mutations in specific pathways like NF-kB and IFN, while pDC-AML shows fewer cytogenetic abnormalities and has a high mutation rate of a specific gene in 70% of cases.
  • - The systematic review emphasizes the importance of understanding these genomic features for differentiating
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Objectives: Acute myeloid leukemia (AML) with inv(16)/t(16;16) is among the most frequent AML subtypes. It is recognized by the detection of the fusion which confers a favorable prognosis, irrespective of the presence of secondary cytogenetic abnormalities. However, the effect of additional genetic anomalies on the behavior of inv(16) AML is debatable.

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Article Synopsis
  • R-CHOP immuno-chemotherapy is effective for treating diffuse large B-cell lymphoma (DLBCL), but a significant percentage (30-40%) of patients either don't respond or relapse.
  • Researchers have identified the protein CYCLON as a key factor linked to disease progression and treatment resistance in DLBCL, establishing it as a potential predictor of poor outcomes.
  • The study also highlights the interaction between CYCLON and NPM1, suggesting that their co-expression and specific locations within the cell could provide insights for developing more tailored treatment strategies for high-risk DLBCL patients.
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Article Synopsis
  • * The study analyzed 113 cases of del(11q) MDS, highlighting features like a predominance in females, survival rates similar to other MDS cases, and a specific genetic deletion affecting key genes associated with hematopoiesis.
  • * Findings suggest that the loss of the CADM1 gene, along with other genetic mutations, may play a significant role in the development of del(11q) MDS, indicating its potential as
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Translocation t(4;12)(q11-13;p13) is a recurrent but very rare chromosomal aberration in acute myeloid leukaemia (AML) resulting in the non-constant expression of a CHIC2/ETV6 fusion transcript. We report clinico-biological features, molecular characteristics and outcomes of 21 cases of t(4;12) including 19 AML and two myelodysplastic syndromes (MDS). Median age at the time of t(4;12) was 78 years (range, 56-88).

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Article Synopsis
  • Diffuse large B-cell lymphoma (DLBCL) is a diverse cancer type treated primarily with the R-CHOP immuno-chemotherapy regimen, but about 30% of patients do not respond or experience a relapse.
  • This study examined the expression of biomarkers like c-MYC, p53, and others in a cohort of 94 DLBCL patients to understand their correlation with patient outcomes and tumor characteristics.
  • Results showed that p53 overexpression was linked to poorer outcomes, while the “starry-sky” tissue pattern indicated better survival in certain high-risk DLBCL patients, suggesting that these biomarkers can help inform prognosis and treatment strategies.
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Follicular lymphomas (FLs) with MYC rearrangements (MYC-R) and extra copies of MYC (MYC-EC) are rare and the prognosis impact is uncertain. We conducted a retrospective study including 321 FL patients, among whom 259 (81%) had no 8q24 alterations and 62 (19%) were assigned to 8qAlt. Forty-five cases were classified as MYC-EC and six as MYC-R.

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