Purpose To prospectively assess the clinical impact of expert review of lymphoma diagnosis in France. Materials and Methods From January 2010 to December 2013, 42,145 samples from patients with newly ...diagnosed or suspected lymphomas were reviewed, according to the 2008 WHO classification, in real time by experts through the Lymphopath Network. Changes in diagnosis between referral and expert review were classified as major or minor according to their potential impact on patient care. Results The 42,145 reviewed samples comprised 36,920 newly diagnosed mature lymphomas, 321 precursor lymphoid neoplasms, 314 myeloid disorders, and 200 nonhematopoietic neoplasms, with 4,390 benign lesions. There were 4,352 cutaneous and 32,568 noncutaneous lymphomas. The most common mature noncutaneous lymphomas were diffuse large B-cell lymphomas (32.4%), follicular lymphomas (15.3%), classic Hodgkin lymphomas (13%), peripheral T-cell lymphomas (6.3%) of which angioimmunoblastic T-cell lymphomas (2.3%) were the most frequent, and mucosa-associated lymphoid tissue lymphomas (5.8%). A diagnostic change between referral and expert review occurred in 19.7% of patients, with an estimated impact on patient care for 17.4% of patients. This rate was significantly higher for patients sent with a provisional diagnosis seeking expert second opinion (37.8%) than for patients sent with a formal diagnosis (3.7%). The most frequent discrepancies were misclassifications in lymphoma subtype (41.3%), with 12.3% being misclassifications among small B-cell lymphoma entities. Fewer than 2% of changes were between benign and malignant lymphoid conditions. Minor changes (2.3%) mostly consisted of follicular lymphoma misgrading and diffuse large B-cell lymphoma subtype misclassification. Conclusion To our knowledge, this study provides the largest ever description of the distribution of lymphoma entities in a western country and highlights how expert review significantly contributes to a precise lymphoma diagnosis and optimal clinical management in a proportion of patients.
TET1 genomic breakpoints and clinical features of MLL-TET1 rearrangements have been described in 13 acute leukemia cases, 11 in AML, 2 in B cell-precursor ALL. The incidence of this rare ...translocation was evaluated to 0.3% of MLL rearranged AML cases (5 out of 1590 MLL Meyer C. Leukemia 2013). Although those cases are very uncommon, their study can improve our current understanding of leukemogenesis. We report here the first t(10;11) MLL-TET1 positive case of lymphoblastic T lymphoma occurring in a 31 years old male patient, with a subsequent transformation to AML.
The patient was referred for a large mediastinal mass and right pleural effusion. Mediastinal and bronchus biopsies led to the diagnosis of a precursor-T cell lymphoblastic lymphoma, expressing CD3, CD5, CD4, CD8, CD10 antigens, without any expression of CD34 or CD79.
Molecular analyses of the malignant T-cells showed a clonal TCR gamma-chain gene rearrangement together with HOXA10 overexpression. FISH analysis showed a MLL breakage. The partner gene, TET1, was identified using RP11-9E13 and RP11-314J18 BACs, corresponding to the recurrent translocation t(10;11)(q22;q23). MLL-TET1 fusion transcript was detected (intron 8 of TET1 fused to exon 8 of MLL), as well as its reciprocal transcript.
The patient was treated following the (GELA) LL03 protocol, and was considered in complete remission after induction and consolidation phases. Fourteen months after the diagnosis, a bone marrow examination was performed for thrombopenia (6 G/L) which revealed a myelomonocytic acute leukemia with trilineage dysplasia.
At this time, The MLL-TET1 fusion transcript as well as HOXA10 overexpression was still present but the TCR rearrangement was not detected. A non-familial donor allogeneic bone marrow transplant was performed in CR after intensive chemotherapy, that was complicated by a grade IV acute graft-versus-host disease. The patient died 54 days after the transplant of bacterial sepsis leading to multi-organ failure.
MLL-TET1 fusions have been described in 13 cases in the literature, mainly in AMLs (11/13 cases, mostly AML M4 or M5 cases) and in B-ALLs (2/13 cases). The case reported here presents two interesting features. Firstly, this patient harbors the first MLL-TET1 fusion reported to date in T-ALL, and secondly this case presented a lymphoid to myeloid phenotype switch during the time course of the disease.
This strongly suggests that the translocation occurred very early during hematopoietic differentiation, prior to the lymphoid/myeloid commitment. As described for the Ph1 chromosome rearrangement, the t(10;11) translocation may arise in hematopoietic stem cell rather than in committed progenitors. These features are also described in 8p11 stem cell syndrome that involves FGFR1. In both cases, genetic rearrangements arise in myeloid or lymphoid neoplasms with possible subsequent transformation.
TET family enzymes convert 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) and play a key role in active DNA demethylation. TET1 and TET2 are also the key enzymes responsible for the presence of 5hmC in mouse embryonic stem cells (ESCs) (Koh KP., Cell Stem Cell 2011), and TET1 functions to regulate the lineage differentiation potential of ESCs. In addition to its role in DNA demethylation, TET1 interacts physically with NANOG and NANOG/TET1 co-occupy genomic loci of genes associated with both maintenance of pluripotency and lineage commitment in embryonic stem cells (Costa Y., Nature 2013). Taken together, these observations enlighten possible mechanism of the lineage switch observed in this case, and may be a rationale for using demethylating agents in MLL-TET1 neoplasms.
No relevant conflicts of interest to declare.
Peliosis is a rare vascular lesion that is usually found in the liver, and less frequently in other hematolymphoid organs. We report a case of isolated splenic peliosis discovered in a 65-year-old ...man with an erysipelas and a thrombocytopenia. The computed tomography abdominal scan revealed an heterogen multinodular splenic mass. Splenectomy was performed and platelet counts returned to normal levels. The histopathologic examination revealed dilations of sinuses in the red pulp. The endothelial cells lining cavities stain for CD8 and CD31 but not for CD34. Splenic peliosis is a rare benign disease of unknown aetiology, which belongs to the group of vascular neoplasms of the spleen. The final diagnosis is based on the pathology examen. We review the histologic and immunohistochemical arguments of this diagnostic and expose the differential diagnoses.
Primary myelofibrosis (PMF) is accompanied by an increase in the bloodstream circulation of some adult progenitor cells. Extramedullary hematopoiesis observed in this setting might remind some ...features related to foetal hematopoiesis.
We looked for evidence in favour of this hypothesis in blood samples of a small cohort of untreated patients with PMF (4 pre-fibrotic (PF) and 4 fibrotic (F), defined according to the WHO and Thiele's histopathology score (Blood, 2011)). Patient baseline characteristics are shown below.
IDSexAgePhaseV617F JAK2Hemoglobin (g/dL)Platelets (x109/L)WBC (x109/L)Spleen (cm)General signsIPSSP1M53F+7.282.420+2P2M83PF+11.844755.810-2P4M70F+8.31385.423-3P5M63F-12.918625.418-2P6M64F+8.21460.025+4P7F65PF+12.59058.321-1P8M64PF-8.852324.722+2P9M64PF-9.756633.118-3
We performed a) flow-cytometric analysis for cell subsets related to VSEL, PEC, MPC, HPC; b) RT-PCR for embryonic transcriptional factors NANOG, OCT4, SOX2, LIN28 from MNC fraction (positive control hES, negative control CPRE2 c) in-vitro development of embryonic stem like cells (ESlC) under specific culture conditions. In addition we looked for SRSF2 mutations in order to better characterize PMF stages.
As expected we detected high numbers of circulating CD34+ cells (HPC) (mean 233083±307148/ml (range 4600-783000), with similar numbers in PF- (231125±289553/ml) and F-PMF (235040 ±369156/ml). We were able to detect small numbers of the following cell subsets related to VSEL (size 2-4m) (Fig 1)
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Lin-/CD45-/CD34+ (mean 124±239/ml), Lin-/CD45-/CD133+ (mean 1178±971/ml), Lin-/CD45-/CXCR4+ (mean 1572±1622/ml). Lin-/CD45-CD34+AC133+CXCR4+ cells were detected in 6 of 8 patients (mean 186±375/ml) with F-PMF patients showing higher numbers (279±416/ml) than PF-PMF (63±71/ml). NANOG and OCT4 expression was detected by RT-PCR in all the patients tested. Mean OCT4 expression was about 50% the level of hES, but F-PMF showed higher levels. NANOG expression was similar to that of hES, whereas Sox2 and Lin28 were not expressed in most patients. We failed to observe the in-vitro development of ESlC in the 2 tested patients. PEC (Lin-/CD45-CD34+AC133+KDR+) were detected in all the PF-PMF (185±332/ml) and in 1 of 4 F-PMF (mean 9±18/ml). MPC (Lin-/CD45-CD90+CD105+) were detected in higher numbers in PF-PMF (mean 413±528/ml) than in F-PMF (mean 157±216/ml). We were not able to detect mutations in the hot spot of SRSF2 (codons 93,94,95).
Small numbers of cell subsets displaying morphologic and immunophenotypic features of VSELs were detected in PMF patients. However, we are not able to define these as fully specific VSELs according to previous works that defined them (Kucia, Leukemia 2006). Interestingly Lin-/CD45-CD34+AC133+CXCR4+ cells were observed in higher numbers in F-PMF, supporting in part our hypothesis that PMF evolution can be associated to the recruitment and circulation of some primitive progenitors (dormant in the adult life) as it can be observed during the foetal period. This recruitment also involves HPC. Moreover although all patients expressed OCT4 and NANOG, OCT4 expression was higher in F-PMF. As expected PEC circulate in higher numbers in PF-PMF compared to F-PMF. Interestingly both F-PMF and PF-PMF were associated to the circulation of significant numbers of MPC but higher numbers observed in PF-MFP might be interpreted either as a necessary recruitment to establish extra-medullary stroma or due to the exit from bone marrow of highly proliferative MPC. Whether all these different circulating progenitor cells, are clonally or not clonally related to the PMF pathogenesis or to unspecific mobilisation secondary to bone marrow microenvironment injury cannot be determined from these preliminary results.
No relevant conflicts of interest to declare.
Summary
The World Health Organization Classification of Lymphoid Neoplasms identifies Burkitt's lymphoma/leukaemia (BL) as a single entity, characterized by unique clinical and genetic features that ...require specific high intensity chemotherapy regimens. Although remarkable successes in the treatment of the disease have been observed, when compared with paediatric patients, adults are less likely to reach stable complete remission. We investigated 32 BL cases, composed in equal part by adults and children that were treated with the French LMB regimen, for factors that may be implicated in chemoresistance. Immunohistochemical detection of procaspase‐8, caspase‐3a, survivin, p53, CD95, c‐Flip and Phospho‐RelA (Ser536) was investigated on paraffin‐embedded tissues. The expression of c‐Flip was found highly related to a poor prognosis, mostly characterized by adults with a chemoresistant disease, resulting in a high death rate within the first year of diagnosis. The 2‐year overall survival with c‐Flip expression was 24% compared with 93% in the absence of this marker (P = 0·04). All c‐Flip‐positive BL cases presented a nuclear Phospho‐RelA (Ser536) localization, suggesting the presence of an active nuclear factor (NF)‐κB transcription pathway. These findings show that c‐Flip could be a reliable prognostic factor in BL, suggesting new therapeutic approaches that target the NF‐κB pathway.
Panels of immunological markers are useful in refining diagnosis in view of certain variability between B‐cell leukaemias. A statistical multivariate approach was used on 100 B leukaemias ...(preliminary sample) to explore the potential value of the combination of CD43, and the classical markers CD5, CD23, CD79b, FMC7, CD22 and surface immunoglobulin to differentiate chronic lymphoid leukaemia (CLL) from lymphoma (non‐CLL). CD43 was highly effective (P < 0·00001) and its inclusion in the panels improved the accuracy of discrimination in a ‘control’ sample of 74 B leukaemias to 98·6%. Inclusion of CD43 facilitates the diagnosis of B‐lymphoproliferative disorders and improves their classification.
Multivariate analysis classification of chronic lymphocytic leukemia (CLL) and lymphoma (non-CLL) disorders is investigated in 299 patients by an extended panel of surface markers, and compared with ...Matutes classical scoring proposal. Diagnosis was based on clinical features, cell morphology, node or bone marrow histology, and immunological scoring system. Results are obtained on directly labeled tumoral cells by flow cytometry gating. Patients included 154 CLL, 2 Richter transformation, and 143 lymphoma (26 follicular, 49 lymphocytic, 18 other low-grade, 7 Waldenström macroglobulinemia, 13 mantel, 11 diffuse large-cell, 6 Burkitt, 4 marginal zone-cell, 5 hairy-cell leukemia, 2 MALT, 1 prolymphocytic leukemia, 1 SLVL). For CD43, FMC7, CD23, CD5, CD79b (% stained cells) and CD20, CD22 surface antigen intensities Chi-Square values indicate very high probability of correct classification (varing from 621 to 94.9; p<0.0000). If, alternatively, % of CD22, CD20, CD19 and intensities of CD79b, CD5, CD19, CD43, CD23 and kappa/lamba chains are employed, Chi-Square yields values of lower significance (varing from 65 to 0.1; p<0.0000 to 0.6573). Using classical panel scoring with CD79b, 82.4 % of patients were correctly classified, compared to 84.5% after replacing CD79b by CD22 intensity. If CD43 is added, correct classification increased to 89.6% and 88.1% of patients, respectively; this improvement is due to better allocation of CLL. In discriminant analysis 91.3% of patients are correctly classified with the panel including CD79b, and 90.9% with CD22 intensity. CD43 enhances the allocation of either one to 94.3%. Using our previous discriminant analysis with CD79b (Jung G, et al. Br J Haematol. 2003; 120:496–499), this blind analysis correctly classified the population in 87.1%, compared to 91.3% with the new one. By adding CD43, it moved from 92.4% up to 94.3%. In order to find the optimal combination of the selected best markers, a stepwise probit discrimination was performed. Using CD43 and FMC7 yields a correct classification of 90.3%; after addition of CD5, CD79b, CD23, and CD22 intensity, efficiency increased to 94.6%. Further added markers don't improve classification. Efficiency of this panel was further confirmed by hierarchical cluster and principal components analysis. Cluster analysis with squared Euclidian distances separated CLL from non-CLL patients with low overlaps: 86.6% of cases are correctly identified. Separated points in the plot representing patients with CLL and non-CLL, obtained by principal components analysis of surface markers, confirm the high predictive potential of this panel. The same analysis of surface marker positions for non-CLL suggests use of: % of CD79b, FMC7, and CD22 intensity, and for CLL: % of CD5, CD23, CD43. So, the addition of CD43 improves as well the discriminant function as the scoring system. Our selected panel of best markers is useful in distinguishing CLL from non-CLL and offers a better distinction by discriminant analysis. Furthermore quantitative expression of each marker and its predictive value improve diagnosis and classification.
The progressive deterioration of the neuromuscular axis is typically observed in degenerative conditions of the lower motor neurons, such as amyotrophic lateral sclerosis (ALS). Neurodegeneration in ...this disease is associated with systemic metabolic perturbations, including hypermetabolism and dyslipidemia. Our previous gene profiling studies on ALS muscle revealed down-regulation of delta-9 desaturase, or SCD1, which is the rate-limiting enzyme in the synthesis of monounsaturated fatty acids. Interestingly, knocking out SCD1 gene is known to induce hypermetabolism and stimulate fatty acid beta-oxidation. Here we investigated whether SCD1 deficiency can affect muscle function and its restoration in response to injury. The genetic ablation of SCD1 was not detrimental per se to muscle function. On the contrary, muscles in SCD1 knockout mice shifted toward a more oxidative metabolism, and enhanced the expression of synaptic genes. Repressing SCD1 expression or reducing SCD-dependent enzymatic activity accelerated the recovery of muscle function after inducing sciatic nerve crush. Overall, these findings provide evidence for a new role of SCD1 in modulating the restorative potential of skeletal muscles.
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