Allogeneic transplantation in advanced cutaneous T-cell lymphomas (CUTALLO): a propensity score matched controlled prospective study.

BACKGROUND: Advanced-stage cutaneous T-cell lymphomas (CTCLs) are rare, usually refractory, and fatal diseases. Case series have suggested that allogeneic haematopoietic stem cell transplantation (HSCT) might improve the prognosis of advanced-stage CTCLs. The objective of this study was to investigate the effect of allogeneic HSCT compared with non-HSCT therapy on the outcome of individuals with advanced-stage CTCLs. METHODS: In this prospective, multicentre, matched controlled trial, conducted at 30 hospitals, participants with advanced CTCLs were allocated treatment: if they had an available compatible related donor they were assigned to allogeneic HSCT, or if not they were allocated to non-allogeneic HSCT therapy. Key inclusion criteria were participants aged 18-70 years, with advanced stage mycosis fungoides or Sézary syndrome, and at least one poor prognostic criteria. Participants were excluded if they were not in complete or partial remission of the disease. Propensity score 1:1 matching with replacement (ie, that each participant treated with HSCT was matched to the participant with the closest propensity score treated with non-HSCT therapy, even if they had already been matched) was used to handle confounding factors, with the balance of covariate distribution between HSCT and non-HSCT groups assessed using standardised mean differences. The primary endpoint was progression-free survival in the matched intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02520908), and is currently active but not recruiting. FINDINGS: From June 1, 2016, to March 3, 2022, total of 99 participants were enrolled at 17 centres in France. Participants with a sibling or matched unrelated donor were assigned to allogeneic HSCT (HSCT group, n=55 [56%]) and participants without a donor were assigned to non-allogeneic HSCT treatment (non-HSCT group, n=44 [44%]). The median follow-up among survivors was 12·6 months (IQR 11·0-35·2). In the HSCT group, 51 participants (93%) were 1:1 matched to participants from the non-HSCT group. In the intention-to-treat analysis, median progression-free survival was significantly longer in the HSCT group (9·0 months [95% CI 6·6-30·5]) than in the non-HSCT group (3·0 months [2·0-6·3]), with a hazard ratio of 0·38 (95% CI 0·21-0·69; p<0·0001). In the per-protocol population, 40 participants (78%) in the HSCT group had 101 serious events and 29 participants (67%) in the non-HSCT group had 70 serious adverse events. The most common serious adverse event other than graft-versus-host disease in both groups was infections, occurring in 30 participants (59%) in the HSCT group and in 19 participants (44%) in the non-HSCT group. INTERPRETATION: Allogeneic HSCT was associated with significantly longer progression-free survival in participants with advanced-stage CTCLs. These results indicate that allogeneic HSCT treatment should be made available to individuals with high-risk, advanced-stage mycosis fungoides or Sézary syndrome who achieve pre-transplant disease remission. FUNDING: French Ministry of Health, National Cancer Institute, Programme Hospitalier de Recherche Clinique en Cancérologie.

Machine learning-based improvement of MDS-CBC score brings platelets into the limelight to optimize smear review in the hematology laboratory.

BACKGROUND: Myelodysplastic syndromes (MDS) are clonal hematopoietic diseases of the elderly characterized by chronic cytopenias, ineffective and dysplastic haematopoiesis, recurrent genetic abnormalities and increased risk of progression to acute myeloid leukemia. A challenge of routine laboratory Complete Blood Counts (CBC) is to correctly identify MDS patients while simultaneously avoiding excess smear reviews. To optimize smear review, the latest generations of hematology analyzers provide new cell population data (CPD) parameters with an increased ability to screen MDS, among which the previously described MDS-CBC Score, based on Absolute Neutrophil Count (ANC), structural neutrophil dispersion (Ne-WX) and mean corpuscular volume (MCV). Ne-WX is increased in the presence of hypogranulated/degranulated neutrophils, a hallmark of dysplasia in the context of MDS or chronic myelomonocytic leukemia. Ne-WX and MCV are CPD derived from leukocytes and red blood cells, therefore the MDS-CBC score does not include any platelet-derived CPD. We asked whether this score could be improved by adding the immature platelet fraction (IPF), a CPD used as a surrogate marker of dysplastic thrombopoiesis. METHODS: Here, we studied a cohort of more than 500 individuals with cytopenias, including 168 MDS patients. In a first step, we used Breiman's random forests algorithm, a machine-learning approach, to identify the most relevant parameters for MDS prediction. We then designed Classification And Regression Trees (CART) to evaluate, using resampling, the effect of model tuning parameters on performance and choose the "optimal" model across these parameters. RESULTS: Using random forests algorithm, we identified Ne-WX and IPF as the strongest discriminatory predictors, explaining 37 and 33% of diagnoses respectively. To obtain "simplified" trees, which could be easily implemented into laboratory middlewares, we designed CART combining MDS-CBC score and IPF. Optimal results were obtained using a MDS-CBC score threshold equal to 0.23, and an IPF threshold equal to 3%. CONCLUSIONS: We propose an extended MDS-CBC score, including CPD from the three myeloid lineages, to improve MDS diagnosis on routine laboratory CBCs and optimize smear reviews.

A hierarchical approach in the diagnostic workflow of chronic myelomonocytic leukemia: Pivotal role of the "Mono-dysplasia-score" combined with flow cytometric quantification of monocyte subsets.

INTRODUCTION: Monocytosis is a frequent trigger for blood smear review in a routine hematology laboratory whereas chronic myelomonocytic leukemia (CMML) is infrequent and arises mostly in elderly patients. In order to define the best workflow for monocytosis, we studied three diagnostic approaches: the classical morphology approach (blood smear review), the flow cytometry assay (quantification of monocyte subsets as described by Selimoglu-Buet et al in 2015), and the "mono-dysplasia-score" also referred to as "Monoscore (as described by our team in 2018 using the structural parameters of the Sysmex XN™ analyzers). METHODS: Studying a multicentric cohort of 196 nonclonal monocytoses and CMML patients aged over 50 years, we compared the diagnostic performance of the three approaches alone and in combination to propose a diagnostic decision tree. RESULTS: In patients presenting with additional criteria for slide review to monocytosis (37% of our cohort), we propose to sequentially combine morphology, Monoscore, and flow cytometry. On the contrary, for patients with isolated monocytosis (63%), slide review is not mandatory and we suggest performing flow cytometry depending on the Monoscore value. Using the proposed algorithm, 98% of CMML patients would have been correctly identified, slide review rate drastically reduced, and flow cytometry would have been carried out in 44% of patients. CONCLUSION: We have shown that implementation of Monoscore is a useful input filter to significantly reduce slide reviews without losing sensitivity and that flow cytometry is a performant technique in the second step of the diagnostic workup of CMML.

Regression of splenic lymphoma with villous lymphocytes after treatment of hepatitis C virus infection.

BACKGROUND: Some epidemiologic studies suggest a link between hepatitis C virus (HCV) infection and some B-cell non-Hodgkin's lymphomas. We undertook this study after a patient with splenic lymphoma with villous lymphocytes had a hematologic response after antiviral treatment of HCV infection. METHODS: Nine patients who had splenic lymphoma with villous lymphocytes and HCV infection were treated with interferon alfa-2b (3 million IU three times per week) alone or in combination with ribavirin (1000 to 1200 mg per day). The outcomes were compared with those of six similarly treated patients with splenic lymphoma with villous lymphocytes who tested negative for HCV infection. RESULTS: Of the nine patients with HCV infection who received interferon alfa, seven had a complete remission after the loss of detectable HCV RNA. The other two patients had a partial and a complete remission after the addition of ribavirin and the loss of detectable HCV RNA. One patient had a relapse when the HCV RNA load again became detectable in blood. In contrast, none of the six HCV-negative patients had a response to interferon therapy. CONCLUSIONS: In patients with splenic lymphoma with villous lymphocytes who are infected with HCV, treatment with interferon can lead to regression of the lymphoma.

Paris-Trousseau syndrome : clinical, hematological, molecular data of ten new cases.

Paris-Trousseau syndrome (PTS) is an inherited disorder characterized by mild hemorragic tendency associated with 11q chromosome deletion. Here we report ten new patients (5 boys, 5 girls) with complete clinical history, biological data, ultra-structural and molecular investigations. Thrombocytopenia is chronic in all the patients except two boys in whom it disappeared during the two first years of life. On Romanovsky stained peripheral blood smears, abnormal platelets with giant granules were detected in all the children and confirmed by electron microscopy (EM). On bone marrow smears, dysmegakaryopoiesis with many micromegakaryocytes was constantly observed. Abnormal alpha-granules were virtually absent from bone marrow and cultured megakaryocytes, while EM detected numerous images of granule fusion within blood platelets. Molecular analyses evidenced that the fli-1 gene is deleted in all the patients except one confirming the crucial role of the transcription factor FLI-1 in megakaryopoiesis. In summary, this study documents ten new cases of PTS with characteristic alpha-granule abnormalities, and shows the putative pathogenic role of fli-1 gene in the pathophysiology of this syndrome.

Unusual evolution of Waldenström's macroglobulinemia into osteolytic myeloma.

We report the unusual transformation of a case of Waldenström's macroglobulinemia (WM) into IgM multiple myeloma (MM). The initial clinical and biological presentation of the disease was typical smouldering WM, with lymphocytic infiltration of the bone marrow. Five years later, signs of transformation appeared: the patient presented with diffuse osteolytic bone lesions without organomegaly, and the bone marrow was infiltrated with characteristic malignant plasma cells. Electron microscopy (EM) examination showed that the endoplasmic reticulum (ER) of the dysmorphic plasma cells contained monoclonal IgM. Immunolabeling for calreticulin, a resident protein of the ER, demonstrated unequivocally that the characteristic intranuclear inclusions were indeed part of ER. Flow cytometry revealed an MM profile for the cellular proliferation. Molecular biology performed on the final marrow could only retrieve a single cellular clone. In conclusion, this is the first documented description of the transformation of typical WM into an aggressive form of MM.

Platelet shape change and subsequent glycoprotein redistribution in human stenosed arteries.

Shear stress encountered in stenosed human arteries is able to induce a certain range of platelet activation. In order to determine the extent of platelet shape change induced by high shear rate conditions, we used electron microscopy (EM) and immuno-EM to study platelet ultrastructure from blood flowing in vivo through stenosed arteries. Then it was compared with platelets from healthy controls exposed in vitro to a shear rate of 4000 s(-1). Six patients with stenosed arteries (iliac, femoral and renal) were investigated at the time of transcutaneous angiography. Blood was harvested from the same catheter in the stenosed artery and in the abdominal aortic artery (control sample), each patient being its own control. The percentage of platelets with shape changes (loss of discoid form, pseudopod emission, organelle centralisation) significantly increased in samples from stenosed arteries. Shape change was concomitant with the membrane glycoprotein IIb-IIIa distribution at the pseudopod extremities. These activated platelets had not completed secretion and were maintained in a reversible activation state. Similar results were obtained on platelets from healthy donors submitted in vitro to a high shear rate. In conclusion, this study shows that the high shear rate encountered in human stenosed arteries is able to induce shape change and reversible activation of platelets in vivo.