Unlocking Predictive Power: Quantitative Assessment of CAR-T Expansion with Digital Droplet Polymerase Chain Reaction (ddPCR).

Flow cytometry (FCM) and quantitative PCR (qPCR) are conventional methods for assessing CAR-T expansion, while digital droplet PCR (ddPCR) is emerging as a promising alternative. We monitored CAR-T transcript expansion in 40 B-NHL patients post-infusion of CAR-T products (axi-cel; tisa-cel; and brexu-cel) with both His-Tag FCM and ddPCR techniques. Sensitivity and predictive capacity for efficacy and safety outcomes of ddPCR were analyzed and compared with FCM. A significant correlation between CAR-T counts determined by FCM and CAR transcripts assessed by ddPCR (p < 0.001) was observed. FCM revealed median CD3+CAR+ cell counts at 7, 14, and 30 days post-infusion with no significant differences. In contrast, ddPCR-measured median copies of CAR-T transcripts demonstrated significant lower copy numbers in tisa-cel recipients compared to the other products at day 7 and day 14. Patients with a peak of CAR transcripts at day 7 exceeding 5000 copies/microg gDNA, termed "good CAR-T expanders", were more likely to achieve a favorable response at 3 months (HR 10.79, 95% CI 1.16-100.42, p = 0.036). Good CAR-T expanders showed superior progression-free survival at 3, 6, and 12 months compared to poor CAR-T expanders (p = 0.088). Those reaching a peak higher than 5000 copies/microg gDNA were more likely to experience severe CRS and ICANS. DdPCR proves to be a practical method for monitoring CAR-T expansion, providing quantitative information that better predicts both treatment outcomes and toxicity.

Inflammation and acute cardiotoxicity in adult hematological patients treated with CAR-T cells: results from a pilot proof-of-concept study.

AIMS: Chimeric Antigen Receptor-T (CAR-T) cell infusion is a rapidly evolving antitumor therapy; however, cardiovascular (CV) complications, likely associated with cytokine release syndrome (CRS) and systemic inflammation, have been reported to occur. The CARdio-Tox study aimed at elucidating incidence and determinants of cardiotoxicity related to CAR-T cell therapy. METHODS: Patients with blood malignancies candidate to CAR-T cells were prospectively evaluated by echocardiography at baseline and 7 and 30 days after infusion. The study endpoints were i) incidence of cancer therapy-related cardiac dysfunction (CTRCD), CTRCD were also balanced for any grade CRS, but CTRCD occurred of Cardiology Guidelines on Cardio-Oncology (decrements of left ventricular ejection fraction (LVEF) or global longitudinal strain (GLS) and/or elevations of cardiac biomarkers (high sensitivity troponin I, natriuretic peptides) and ii), correlations of echocardiographic metrics with inflammatory biomarkers. RESULTS: Incidence of CTRCD was high at 7 days (59,3%), particularly in subjects with CRS. The integrated definition of CTRCD allowed the identification of the majority of cases (50%). Moreover, early LVEF and GLS decrements were inversely correlated with fibrinogen and interleukin-2 receptor levels (p always ≤ 0.01). CONCLUSIONS: There is a high incidence of early CTRCD in patients treated with CAR-T cells, and a link between CTRCD and inflammation can be demonstrated. Dedicated patient monitoring protocols are advised.

PlentiPlex™ MYD88 Waldenström lymphoma qPCR assay: A highly sensitive method for detection of MYD88 L265P mutation.

INTRODUCTION: Agarose gel-based conventional and real-time allele-specific polymerase chain reaction (AS-PCR) assays are currently used for sensitive detection and quantification of MYD88 L265P mutation. Visual inspection of an agarose gel can often be ambiguous. We propose a new allele-specific quantification PCR (AS-qPCR) assay, PlentiPlex™ MYD88 Waldenström lymphoma qPCR assay, that uses Intercalating Nucleic Acid (INA®) technology for increased affinity and specificity. METHODS: This study compares PlentiPlex™ MYD88 Waldenström lymphoma qPCR assay with conventional AS-PCR. We included a total of 102 peripheral and bone marrow blood samples from 94 patients with a lymphoproliferative disorder. Droplet digital PCR (ddPCR) was used as a third method in case of discrepancy. RESULTS: A positive percent agreement of 100% (95% CI 0.92-1.0) and a negative percent agreement of 98% (95% CI 0.90-1.0) were found between the conventional AS-PCR and the AS-qPCR methods. Including the ddPCR results to validate the discrepant cases, the sensitivity and specificity of PlentiPlex™ MYD88 Waldenström lymphoma qPCR Assay were 1.0 (95% CI 0.97-1.0) and 1.0 (95% CI 0.96-1.0), respectively. CONCLUSION: Our data demonstrate that PlentiPlex™ MYD88 Waldenström lymphoma qPCR assay is a fast, highly sensitive, and specific method for the detection of MYD88 L265P compared with conventional AS-PCR.

Multicolor flow cytometry on pericardial effusion for a prompt diagnosis and treatment of hematological malignancies with heart involvement.

Background: Malignancies represent 15-50% of total causes of pericardial effusions (PE). Routine analyses recommended to be performed on pericardial fluid include general chemistry, cytology, polymerase chain reaction, and microbiological cultures. Multicolor flow cytometry (FC) is a laboratory test that already proved to be useful in the detection of lymphoproliferative and metastatic malignancies in pleural and peritoneal effusions, but current guidelines do not mention its use on PE to reach a diagnosis. Methods: Our institutional protocol foresees to routinely perform a multicolor FC analysis on pericardial fluid samples obtained by pericardiocentesis, in addition to other guidelines-recommended analyses. A sample of 15-30 ml is analyzed using a lyse and wash staining method using combination panels of antibodies, allowing to detect specific cellular subpopulations, analyzing tens to hundreds of thousands of cells in few seconds. The present manuscript aims to report our single-center experience with this diagnostic tool in patients presenting with PE requiring pericardiocentesis. Results: Routine use of multicolor FC on pericardial fluid samples in our institution allowed to reach a definite diagnosis of cardiac lymphomas in two patients presenting with otherwise unexplained severe PE. This resulted in immediate start of combined immunotherapy, with patients' clinical improvement. At 6 months follow-up both patients are alive and presented a complete disease regression. Conclusion: Preliminary evidence from routine use of multicolor FC on PE support that this is a promising tool to reach a rapid diagnosis of hematological malignancies with heart involvement, leading to a prompt initiation of targeted therapies.

PD-L1 expression in peripheral blood granulocytes at diagnosis as prognostic factor in classical Hodgkin lymphoma.

Hodgkin lymphoma (HL) is a neoplastic disease in which the inflammatory microenvironment plays a pivotal role in the tumorigenesis. Neutrophilia is a typical finding in HL at diagnosis and, in particular, in association with lymphocytopenia, is a negative prognostic factor. As the immune checkpoint Programmed Death (PD)-L1/PD-1 has become an important therapeutic target, we were interested in the expression of PD-L1 in peripheral blood (PB) leukocytes using flow cytometry and RT-PCR in patients with HL and healthy controls. Granulocytes were the major PB cell fraction expressing PD-L1. PD-L1 expression on granulocytes was higher in patients with HL than in controls and correlated with lower T-cell numbers in PB. We analyzed for associations between PD-L1 expression in PB granulocytes at the time of diagnosis with patient characteristics and outcome in 126 patients with HL treated with standard chemotherapy adriamycin, bleomycin, vinblastine, and dacarbazine. Increased PD-L1 expression in PB associated with advanced disease, systemic symptoms, positive interim positron emission tomography, and inferior progression-free survival (PFS). PFS at 4 years was 81% (95% C.I., 71-87%) in patients with normal PD-L1 expression and 56% (95% C.I., 35-72%) in patients with higher-than-normal PD-L1 expression (p = 0.002). In conclusion, PD-L1 expression in PB could become a potentially actionable prognostic factor in HL.

Expression of PD-L1 in peripheral blood reflects disease burden and predicts interim PET result and prognosis in classical HL.

Cytomorphology of normal, reactive, dysmorphic, and dysplastic megakaryocytes in bone marrow aspirates.

This paper aims to emphasize the importance of applying international consensus guidelines to detect qualitative and quantitative abnormalities of megakaryocytes on smears of bone marrow aspirates (BMA) for a shared and harmonized diagnostic path between different laboratories. Careful evaluation of megakaryocytes on BMA smears represents a cornerstone in the diagnosis of most clonal and nonclonal hematological diseases. Images associated with the detailed morphologic description of normal, reactive, abnormal, and dysplastic megakaryocytes are also reported together with examples of similar cells that, if not promptly identified, can lead to a morphological misdiagnosis.

SARS CoV 2 infection in chronic myelogenous leukemia: Severe hematological presentation.

Infection with SARS-CoV-2, the cause of coronavirus infectious disease-19 (COVID-19), has caused a pandemic. Few data are available about the risk of COVID-19 infection in persons with hematological cancer, but controversy whether these persons have the same clinical signs and outcomes. We describe a case of life-threatening COVID-19 infection complicated by severe anemia in patients affected also by chronic myelogenous leukemia. The screening for RBC antibodies and the direct antiglobulin test (DAT) turned positive. The identification of the antibodies, showed the presence of an alloantibody with anti-Lewis b specificity, which was reactive at room temperature, in the anti-human globulin phase (AGH) and with papain-treated red blood cells. At the same time hemophagocytic lymphohistiocytosis (HLH), on the basis of major laboratory findings including hyperferritnemia, increase of triglicerides levels and according to the HLH score was suspected. Patients received antiviral therapy, steroids and intravenous immunoglobulins. Hemolysis resolved and ferritin dramatically decreased after administration of Ig and a Afull recovery was achieved after viral infection resolution.This case highlights the novel and multifaceted hematological findings during sever COVID 19 infection. COVID 19-related pneumonia is mediated by hyper activation of effector T cells and excessive production of inflammatory cytokines, such as IL-6, IL-1, interferon-gamma, and TNF. This inflammatory process called "cytokine storm" is a life-threatening complication of COVID 19 infection. In this case severe immunohematological consequences are reported for the first time and recognition of this complications are probably underestimated.