Loss of hematopoietic progenitors heterogeneity is an adverse prognostic factor in lower-risk myelodysplastic neoplasms

Myelodysplastic neoplasms (MDS) are characterized by clonal evolution starting from the compartment of hematopoietic stem and progenitors cells (HSPCs), leading in some cases to leukemic transformation. We hypothesized that deciphering the diversity of the HSPCs compartment may allow for the early detection of an emergent sub-clone that drives disease progression. Deep analysis of HSPCs repartition by multiparametric flow cytometry revealed a strong disorder of the hematopoietic branching system in most patients at diagnosis with different phenotypic signatures closely related to specific MDS features. In two independent cohorts of 131 and 584 MDS, the HSPCs heterogeneity quantified through entropy calculation was decreased in 47% and 46% of cases, reflecting a more advanced state of the disease with deeper cytopenias, higher IPSS-R risk and accumulation of somatic mutations. We demonstrated that patients with lower-risk MDS and low CD34 + CD38+HSPCs entropy had an adverse outcome and that this parameter is as an independent predictive biomarker for progression free survival, leukemia free survival and overall survival. Analysis of HSPCs repartition at diagnosis represents therefore a very powerful tool to identify lower-risk MDS patients with a worse outcome and valuable for clinical decision-making, which could be fully integrated in the MDS diagnostic workflow.

Minimal Residual Disease in Acute Myeloid Leukemia: Old and New Concepts

Minimal residual disease (MRD) is of major importance in onco-hematology, particularly in acute myeloid leukemia (AML). MRD measures the amount of leukemia cells remaining in a patient after treatment, and is an essential tool for disease monitoring, relapse prognosis, and guiding treatment decisions. Patients with a negative MRD tend to have superior disease-free and overall survival rates. Considerable effort has been made to standardize MRD practices. A variety of techniques, including flow cytometry and molecular methods, are used to assess MRD, each with distinct strengths and weaknesses. MRD is recognized not only as a predictive biomarker, but also as a prognostic tool and marker of treatment efficacy. Expected advances in MRD assessment encompass molecular techniques such as NGS and digital PCR, as well as optimization strategies such as unsupervised flow cytometry analysis and leukemic stem cell monitoring. At present, there is no perfect method for measuring MRD, and significant advances are expected in the future to fully integrate MRD assessment into the management of AML patients.

Use of a hybrid intelligence decision tree to identify mature B-cell neoplasms

BACKGROUND

Mature B-cell neoplasms are challenging to diagnose due to their heterogeneity and overlapping clinical and biological features. In this study, we present a new workflow strategy that leverages a large amount of flow cytometry data and an artificial intelligence approach to classify these neoplasms.

METHODS

By combining mathematical tools, such as classification algorithms and regression tree (CART) models, with biological expertise, we have developed a decision tree that accurately identifies mature B-cell neoplasms. This includes chronic lymphocytic leukemia (CLL), for which cytometry has been extensively used, as well as other non-CLL subtypes.

RESULTS

The decision tree is easy to use and proposes a diagnosis and classification of mature B-cell neoplasms to the users. It can identify the majority of CLL cases using just three markers: CD5, CD43, and CD200.

CONCLUSION

This approach has the potential to improve the accuracy and efficiency of mature B-cell neoplasm diagnosis.

Prognostic Impact of Unsupervised Early Assessment of Bulk and Leukemic Stem Cell Measurable Residual Disease in Acute Myeloid Leukemia

PURPOSE

Acute myeloid leukemias (AML) are clonal diseases that develop from leukemic stem cells (LSC) that carry an independent prognostic impact on the initial response to induction chemotherapy, demonstrating the clinical relevance of LSC abundance in AML. In 2018, the European LeukemiaNet published recommendations for the detection of measurable residual disease (Bulk MRD) and suggested the exploration of LSC MRD and the use of multiparametric displays.

EXPERIMENTAL DESIGN

We evaluated the performance of unsupervised clustering for the post-induction assessment of bulk and LSC MRD in 155 patients with AML who received intensive conventional chemotherapy treatment.

RESULTS

The median overall survival (OS) for Bulk+ MRD patients was 16.7 months and was not reached for negative patients (HR, 3.82; P < 0.0001). The median OS of LSC+ MRD patients was 25.0 months and not reached for negative patients (HR, 2.84; P = 0.001). Interestingly, 1-year (y) and 3-y OS were 60% and 39% in Bulk+, 91% and 52% in Bulk-LSC+ and 92% and 88% in Bulk-LSC-.

CONCLUSIONS

In this study, we confirm the prognostic impact of post-induction multiparametric flow cytometry Bulk MRD in patients with AML. Focusing on LSCs, we identified a group of patients with negative Bulk MRD but positive LSC MRD (25.8% of our cohort) with an intermediate prognosis, demonstrating the interest of MRD analysis focusing on leukemic chemoresistant subpopulations.

Twenty-four-hour intragastric acidity following early evening or bedtime administration of roxatidine in duodenal ulcer patients

AIM

To assess the usefulness of early evening administration of roxatidine 150 mg as an alternative to the traditional bedtime regimen.

METHODS

Twenty-four patients with healed duodenal ulcer were dosed according to a balanced incomplete-block design, with two of the following regimens: placebo, roxatidine 150 mg at 07.30 h (early evening) or roxatidine 150 mg at 22.00 h (bedtime). Twenty-four-hour intragastric pH-metry was started at 18.00 h on the first day of dosing. Median pH was determined for the 24-h period, and for the following time intervals: 20.00-00.00 h, 00.00-08.00 h and 08.00-18.00 h. Percentage time in the 24-h period with pH greater than 4.0 was also calculated.

RESULTS

The two roxatidine regimens proved significantly superior to the placebo, decreasing 24-h acidity for all the time intervals, except the 20.00-00.00 h period, when mean intragastric pH with the early evening regimen (4.5 +/- 1.1) proved significantly higher than after placebo (2.2 +/- 1.0) or when roxatidine was taken at bedtime (2.4 +/- 1.1).

CONCLUSION

Early evening administration of roxatidine may afford satisfactory control of 24-h acidity, offering a useful alternative to conventional bedtime administration.

Double-blind, randomized trial of roxatidine 150 mg in the early evening versus bedtime administration in the short-term treatment of duodenal ulcer

AIM

To compare the efficacy and tolerability of early evening (19.00-21.00 hours) vs. bedtime (22.00-00.00 hours) oral administration of roxatidine 150 mg in the short-term treatment of active duodenal ulcer.

METHODS

The trial was randomized, double-blind and double-dummy, with parallel groups. A total of 276 patients were recruited and randomly assigned either to roxatidine in the early evening (n = 139) or roxatidine at bedtime (n = 137).

RESULTS

After 4 weeks, 78% of patients receiving roxatidine in the early evening and 74% of those treated at bedtime had achieved complete healing, as determined by per-protocol analysis. With intention-to-treat analysis the healing rates were 70.5% and 70.8%, respectively. After 8 weeks the healing rates in the early evening and bedtime treatment groups were 92% and 95% (per-protocol analysis) and 78% and 84% (intention-to-treat analysis). Both treatments proved effective in reducing the frequency and severity of daytime and nocturnal epigastric pain, as well as other ulcer-related symptoms.

CONCLUSIONS

This study confirmed the healing and analgesic properties of roxatidine in duodenal ulcer disease. Early evening or bedtime dosing with roxatidine 150 mg resulted in similar 4- to 8-week rates of duodenal ulcer healing.

Double-blind randomized, multicenter study comparing aluminium phosphate gel with rantitidine in the short-term treatment of duodenal ulcer

The efficacy and safety of aluminium phosphate and ranitidine in the short-term treatment of duodenal ulcer were compared in a multicenter, randomized, double-blind study. A total of 304 patients with endoscopically proven active duodenal ulcer were recruited: 153 received 11 g of aluminium phosphate gel five times a day (equivalent to a daily acid buffering capacity of 182 mEq/HC1) and 151 rantitidine 300 mg once daily for 6 weeks. At the end of the treatment period, 74 out of 113 patients (65%) treated with aluminium phosphate and 84 out of 105 patients (80%) treated with rantitidine showed ulcer healing at endoscopy (p = 0.02). Ulcer symptoms, identified as frequency and intensity of daytime and nocturnal epigastric pain, were significantly reduced by both treatments, but rantitidine proved more effective than aluminium phosphate in reducing the frequency of daytime pain (p < 0.01) and its severity (p < 0.01); in contrast, no significant differences were found with regard to frequency and severity of nocturnal pain. The incidence of unwanted effects was significantly higher in the aluminium phosphate group. The main adverse event observed was constipation which, however, was hardly ever severe enough to warrant discontinuing treatment.

DNA sequencing in HydroLink matrices: extension of reading ability to greater than 600 nucleotides

All the systems for optimizing DNA sequencing published so far have introduced modifications regarding: (i) linearization of band migration via ionic strength gradients or wedge-shaped gels; (ii) automatization of band reading via introduction of fluorescent probes; (iii) direct blotting analysis; (iv) pulsed electric fields and (v) discontinuous buffer systems. In all these systems, DNA sequence reading with an accuracy of ca. 98% rarely exceeds a length of 350 bases. We have chosen, in order to increase the reading ability of a single gel, to manipulate the characteristics of the gel matrix. The Seq-HydroLink gel formation here reported allows optimal reading, from a single gel run, of at least 600 bases. In order to guarantee this reading ability in a single run, the upper and lower ends of the ladder are time-resolved, i.e. the same sample is applied to the gel matrix at three different time intervals. The present system represents an increase of at least 30% in reading ability as compared with any type of polyacrylamide gel formulation so far reported.