Blastoid Cells Research Articles

The Value of Sysmex White Precursor Cell Channel in Distinguishing Circulating Large Blastoid Lymphoma Cells from Blasts

Abstract Background There are rare cases of lymphoma presenting with circulating large blastoid cells mimicking blasts. These abnormal cells usually are medium to large in size with high nucleus-to-cytoplasmic ratio, fine to slightly condensed chromatin, prominent nucleoli, and scant to moderate amount of cytoplasm. Distinguishing them from real blasts is challenging, and although flow cytometry provides a definitive answer, pathologists may feel compelled to offer a quick preliminary assessment to the clinical team, particularly during weekends when flow cytometry is not accessible. We have recently replaced the old CBC instrument with Sysmex XN-9100 which incorporates a new white precursor cell channel (WPC). WPC channel is triggered only when Sysmex differential channels (WDF+WNR) produce a combined flag of “blasts/abnormal lymphocytes?”. The WPC will then separate this into a specific flag for either cell type or remove the flag if it is normal. Our study aims to explore the effectiveness of the WPC Channel in distinguishing blastoid lymphoma cells from true blasts. Method Between October 2023 and January 2024, we identified four lymphoma cases exhibiting circulating large blastoid cells. For comparative analysis, we included the most recent seven cases of acute myeloid leukemia (AML) and one case of acute lymphoblastic leukemia (ALL), all featuring medium to large-sized blasts. We collected results from initial testing (WDF+WNR) and WPC reflex testing. The reference for our analysis included manual differentials assisted by CellaVision, pathologist reviews, and immunophenotyping results. Results Within four blastoid lymphoma cases, two were diagnosed as blastoid high-grade B-cell lymphomas, one as diffuse large B-cell lymphoma, and another as chronic lymphocytic leukemia with many blast-like cells observed on the cytospin slide (no smear available). Pathologists reviewed the smears and slides of all four cases, categorizing them as blasts or blast-like cells before flow was run. All cases were initially flagged with “Blasts/Abnormal Lymphocyte?” on Sysmex differential channels but were subsequently flagged only with abnormal lymphocytes after the WPC reflex. For comparison, in 7 AML and 1 ALL cases, the WPC channel flagged blasts in 7 out of the 8 cases following the reflex of initial “Blasts/Abnormal Lymphocyte?” flag. The only case flagged with abnormal lymphocytes but not blasts was a case of AML with monocytic differentiation, characterized by many promonocytes and rare blasts. Conclusion The WPC channel accurately characterized the challenging large blastoid lymphoma cells as abnormal lymphocytes in all four cases, where morphology characterization was difficult. The study’s limitation lies in its small sample size. We are actively accumulating additional cases with circulating blastoid lymphoma cells, alongside control leukemia cases, to further assess the efficacy of the WPC channel.

Clinical and pathological characteristics of blastoid mantle cell lymphoma: a single institution experience.

Blastoid mantle cell lymphoma (B-MCL) is a rare aggressive lymphoma. It is characterized by blastoid morphology with high proliferation and inconsistent immunohistochemistry (IHC), making it a diagnostic challenge for the pathologist. This is a retrospective analytical cohort study. We reviewed biopsy confirmed cases of B-MCL diagnosed over a period of 10 years (January 2012 to December 2022). The clinical presentation, histopathological and IHC findings, treatment received, and survival outcomes were studied. Randomly selected cases of classic MCL (n=12), diagnosed during the same period served as controls. A total of 12 cases were studied. Four cases were transformed from previously diagnosed MCL; 8 cases arose de novo. Mean age was 61.17 years and the male: female ratio was 5:1. Half of the cases showed extra nodal extension and 81.8% had bone marrow involvement. Gastrointestinal tract was the most common site of extra nodal involvement. Histopathological examination showed diffuse involvement of the lymph node with medium sized cells. On immunohistochemistry, one of the cases showed loss of CD5 expression while the other had aberrant CD10 expression. Mean Ki-67 index was 58.09% in the cases and 16.33% in controls and was statistically significant ( p=0.005). The median overall survival (OS) for cases was 2 years vs 8 years in controls. The p53 over expression (>30% nuclear positivity) was seen in 66.6% cases (4/6). There are several factors that contribute to the aggressiveness of B-MCL, and new treatment approaches might be required to improve patient outcomes.

A diagnostic dilemma: distinguishing a sulfasalazine induced DRESS hypersensitivity syndrome from a CD30 + lymphoma in a young patient

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe hypersensitivity reaction characterized by cutaneous rash, lymphadenopathy, fever, eosinophilia, leukocytosis, and life-threatening organ dysfunctions. We describe the case of a 26 year old patient admitted to the Emergency Department for DRESS syndrome after sulfasalazine treatment for rheumatoid arthritis in the right knee. Whole body computer tomography showed multiple neck, chest, and abdominal lymphadenopathy with splenomegaly, massive ascites and severe hepatic cytolysis. Serology results for Epstein-Barr Virus (EBV), influenza, measles, rubella, hepatitis A and B were negative. The histologic analysis of skin, lymph node and bone marrow biopsies could not indicate a classical Hodgkin’s Disease or iatrogenic immunodeficiency/EBV-associated lymphoproliferative disorder (LPD), Hodgkin type. The relatively small caliber of the CD30 + immunoreactive blastoid cells in the lymph nodes suggested reactive immunoblasts rather than Hodgkin cells. The morphologic aspects of the lymph node biopsies with predominance of T-cells were compatible with the diagnosis of a sulfasalazine-induced DRESS syndrome as the patient had a high RegiSCAR score for DRESS. [DRESS Syndrome Foundation: Diagnosis and Treatment. (2023)] The patient’s complex clinical course, marked by two hospital admissions, highlights the challenges in diagnosing and managing DRESS. This case underscores the need for individualized care, close patient monitoring, and further research to better understand DRESS’s underlying mechanisms and optimal therapeutic strategies.

Clinical and pathological characteristics of blastoid mantle cell lymphoma: a single institution experience

Background Blastoid mantle cell lymphoma (B-MCL) is a rare aggressive lymphoma. It is characterized by blastoid morphology with high proliferation and inconsistent immunohistochemistry (IHC), making it a diagnostic challenge for the pathologist. Methods This is a retrospective analytical cohort study. We reviewed biopsy confirmed cases of B-MCL diagnosed over a period of 10 years (January 2012 to December 2022). The clinical presentation, histopathological and IHC findings, treatment received, and survival outcomes were studied. Randomly selected cases of classic MCL (n=12), diagnosed during the same period served as controls. Results A total of 12 cases were studied. Four cases were transformed from previously diagnosed MCL; 8 cases arose de novo. Mean age was 61.17 years and the male: female ratio was 5:1. Half of the cases showed extra nodal extension and 81.8% had bone marrow involvement. Gastrointestinal tract was the most common site of extra nodal involvement. Histopathological examination showed diffuse involvement of the lymph node with medium sized cells. On immunohistochemistry, one of the cases showed loss of CD5 expression while the other had aberrant CD10 expression. Mean Ki-67 index was 58.09% in the cases and 16.33% in controls and was statistically significant (p=0.005). The median overall survival (OS) for cases was 2 years vs 8 years in controls. The p53 over expression (>30% nuclear positivity) was seen in 66.6% cases (4/6). Conclusion There are several factors that contribute to the aggressiveness of B-MCL, and new treatment approaches might be required to improve patient outcomes.

Genetic and prognostic analysis of blastoid and pleomorphic mantle cell lymphoma: a multicenter analysis in China.

Blastoid or pleomorphic mantle cell lymphoma (B/P-MCL) is characterized by high invasiveness and unfavorable outcomes, which is still a challenge for treating MCL. This retrospective study was performed to comprehensively analyze the clinical, genomic characteristics and treatment options of patients with B/PMCL from multicenter in China. Data were obtained from 693 patients with B/PMCL from three centers in China between April 1999 and December 2019. Seventy-four patients with BMCL (n = 43) or PMCL (n = 31) were included in the analysis. The median age of the cohort was 60.0years with a male-to-female ratio of 2.89:1. The 3-year progression-free survival (PFS) and overall survival (OS) rates were 44.1% and 46.0%, respectively. Mutations of TP53, ATM, NOTCH1, NOTCH2, NSD2, SMARCA4, CREBBP, KMT2D, FAT1, and TRAF2 genes were the most common genetic changes in B/P-MCL. Progression of disease within 12months (POD12) could independently predict the poor prognosis of patients with blastoid and pleomorphic variants. Patients with POD12 carried a distinct mutation profile (TP53, SMARCA4, NSD2, NOTCH2, KMT2D, PTPRD, CREBBP, and CDKN2A mutations) compared to patients with non-POD12. First-line high-dose cytosine arabinoside exposure obtained survival benefits in these populations, and BTKi combination therapy as the front-line treatment had somewhat improvement in survival with no significant difference in the statistic. In conclusion, B/P-MCL had inferior outcomes and a distinct genomic profile. Patients with POD12 displayed a distinct mutation profile and a poor prognosis. New therapeutic drugs and clinical trials for B/P-MCL need to be further explored.

Atypical Morphological Presentation of Neoplastic Plasma Cells: A Series of Five Cases

The diagnosis of Multiple Myeloma (MM) is made by demonstration clonal plasma cells in Bone Marrow (BM) aspiration/biopsy, in addition to assessing serum biochemical parameters, conducting radiological examinations, and considering the clinical presentation. In most cases, predominantly mature plasma cells are observed, along with scattered immature forms in the BM. Several morphological variants of plasma cells have been reported, including Auer rod-like inclusions, small lymphocyte-like cells, hairy cell-like cells, anaplastic variants, promonocyte-like cells, crystal-storing histiocytes, Burkitt-like cells, and blastoid cells. In this series of five cases, most showed a typical clinical presentation and laboratory findings suggestive of plasma cell dyscrasia. However, the morphology of each case exhibited unusual morphological variants, posing diagnostic challenges. These variants included Auer rod-like inclusions, small lymphocytes/lymph-plasmacytoid cells, hairy-like cells, multilobulated nuclei, and anaplastic variants mimicking dysplastic megakaryocytes, leading to various differential diagnoses. The age range of these cases was 57-76 years. Most of the cases presented with generalised dull aching body pain. Imaging studies revealed lytic lesions involving various parts of the bone, including the skull, ribs, vertebrae, and femur. Biochemical assays suggested the possibility of plasma cell dyscrasia. Two of the cases had primary Plasma Cell Leukaemia (PCL), which is a rare and highly aggressive plasma cell neoplasm. The anaplastic variant is associated with a poor prognosis, aiding in predicting treatment responses. However, due to the unusual morphological presentation, the diagnosis of MM or PCL was made after conducting ancillary studies such as Serum Protein Electrophoresis (SPEP), serum free light chain assay, Immunofixation Electrophoresis (IFE), and immunophenotyping through Immunohistochemistry (IHC) or flow cytometry

Advanced Pediatric-Type Follicular Lymphoma, Consequences of a Late Presentation in a Resource-Poor Setting: Case Report and Literature Review

AbstractPediatric-type follicular lymphoma (PFL) is a rare, nonaggressive, slow-growing (indolent), non-Hodgkin lymphoma that is typically seen in males as a localized disease with excellent outcomes. It is largely different from follicular lymphoma (FL). Few published studies on PFL are case series in developed nations. We report on a patient with advanced PFL, a 14-year-old female with 5-year history of neck swellings, abdominal distension for a month, and pericardial effusion, among others. The swellings waxed and waned; and involved all the peripheral lymph nodes. Tuberculosis (TB) GeneXpert and human immunodeficiency virus (HIV) screening were negative. She received anti-TB drugs prior to presentation in our hospital where nodal histopathology showed effaced architecture with diffuse follicles and abundant blastoid cells as well as negative CD5 and BCL2, and positive CD10 and CD20. Diagnosis of PFL (stage 3) was made. She completed six courses of cyclophosphamide, doxorubicin, vincristine, and prednisolone and is well 9 months after therapy. The PFL usually presents with stage 1 or 2 disease unlike in the index female case that was also complicated by effusion and ascites due to late presentation. It responded to chemotherapy and has not reoccurred; in contrast to classic FL and reactive follicular hyperplasia (RFH) which should be differentiated from PFL. Although RFH can be caused by TB or HIV, they are not causes of malignant lymphadenopathy. Physicians should be aware of PFL which may present in high clinical stages, but still retain its good prognosis, for the purposes of counseling.

Genomic and Transcriptomic Profiles of Blastoid and Pleomorphic Mantle Cell Lymphoma Are Distinct from Classic Histology Mantle Cell Lymphoma

Introduction - Patients (pts) with mantle cell lymphoma (MCL) with blastoid (B-MCL) and pleomorphic (P-MCL) histology are traditionally considered as high risk; however, there is a paucity of information regarding the differences between P-MCL and B-MCL compared to classic MCL (C-MCL) histology. In this study, we present a comprehensive genomic and transcriptomic portrait of B-MCL and P-MCL. Methods - We conducted comprehensive molecular profiling using whole exome (WES) and bulk RNA sequencing (RNA seq) among the evaluable pt samples (n=260) from our center (MDA cohort) and previously reported cohorts from Bea et al ( PNAS 2013) (n=29) and Agarwal et al ( Nature Medicine 2019) (n=15) respectively. Pts with WES were (n=195) including n=151, n=29 and n=15 for MDA, Bea and Agarwal respectively while 175 pts underwent RNA sequencing (all MDA). This cohort study was conducted under an IRB approved protocol for MCL patients at our center. Patient characteristics, somatic mutation profiles, copy number abnormalities and gene expression profiles (GEP) were analysed. Lymph node, bone marrow, blood samples and any other tissue biopsies were utilized. DNA and RNA were extracted from FFPE sections from lymph nodes and non-nodal tissues. Joint WES and RNA-seq mutation calling, GEP, and transcriptomic cell deconvolution were performed using the BostonGene automated pipeline. WES and bulk RNA sequencing were performed with Illumina HiSeq4000 using a 76bp paired end configuration. Results - Among the 195 pts with WES, the distribution of tissue types was 133 nodal, 33 bone marrow, 25 blood, 4 spleen and other tissues. Mutation distribution and copy number analysis was performed for 99 C-MCL , 72 B-MCL, and 20 P- MCL pts. In the mutation profile, we found that the percentage of ATM mutations was comparable among the 3 pt groups (51%/50%/39%). The frequency of TP53 mutations was significantly lower in C-MCL (23%) compared to B-MCL (51%) and P-MCL (39%) (p < 0.001; Figure 1). NOTCH2 gain of function mutations were found in 11% of B-MCL and 4.6% of C-MCL but not detected in P-MCL. The NFkBIE Y254Sfs*13 mutation was exclusively found in B-MCL. Blastoid samples were enriched with CCND1 E36K mutations (7 of 16 CCND1 mut), while C-MCL had 2 of 16. P-MCL had a higher prevalence of SMARCA4 and DNMT3A mutations compared to B-MCL and C- MCL. We further observe that P-MCL pts exhibited higher polyploidy and aneuploidy than B-MCL and C-MCL ( p < 0.001; Figure 2), indicating that compared to C-MCL, genomic instability decreased from P-MCL to B-MCL. The most frequent arm level amplifications in P-MCL compared to B-MCL were 8q (=MYC) (38%) and 18q (=BCL2) (38%). In C-MCL and B-MCL the 3q (=BCL6) was frequently amplified (28% and 30%). MALT1, Bcl2 and CARD11 gene amplifications were highest in P-MCL. These differences were further supported when the data were compared at the gene level. Comparison of the deletion frequencies revealed that 9p (CDKN2A/B) and 17p (TP53) were frequently lost in B and P-MCL (~40%). Del8p, 6q, 10q, and 16q were frequently deleted in P-MCL compared to B-MCL. At the segmental level, mostly altered segments included del9p21.1-24.3, del13q14.2-14.3, and del17p12-13.3 that span genes like CDKN2A/B, miR15A, and TP53. Next, we performed GSEA analysis using RNA-seq data. The metabolic reprogramming pathway was upregulated in both B and P-MCL compared to C-MCL (p = 0.0096). The proportion of pts with an immune desert (D) “cold” tumor microenvironment associated with refractory disease was higher in P-MCL (50%) than in C or B-MCL. Conclusions -B and P-MCL exhibit a distinct molecular profile compared to C-MCL. P and B-MCL have the highest degree of aneuploidy and exhibit an immune cold tumor microenvironment. Further studies are ongoing to refine the molecular differences among B and P-MCL compared to C-MCL.

Outcomes of patients with blastoid and pleomorphic variant mantle cell lymphoma

AbstractMantle cell lymphoma (MCL) is a B-cell non-Hodgkin lymphoma; data indicate that blastoid and pleomorphic variants have a poor prognosis. We report characteristics and outcomes of patients with blastoid/pleomorphic variants of MCL. We retrospectively studied adults with newly diagnosed MCL treated from 2000 to 2015. Primary objectives were to describe progression-free survival (PFS) and overall survival (OS). Secondary objectives included characterization of patient characteristics and treatments. Of the 1029 patients with MCL studied, a total of 207 neoplasms were blastoid or pleomorphic variants. Median follow-up period was 82 months (range, 0.1-174 months); median PFS was 38 months (95% confidence interval [CI], 28-66) and OS was 68 months (95% CI, 45-96). Factors associated with PFS were receipt of consolidative autologous hematopoietic transplantation (auto-HCT; hazard ratio [HR], 0.52; 95% CI, 0.31-0.80; P < .05), MCL International Prognostic Index (MIPI) intermediate (HR, 2.3; 95% CI, 1.2-4.3; P < .02) and high (HR, 3.8; 95% CI, 2.0-7.4; P < .01) scores, and complete response to induction (HR, 0.29 (95% CI, 0.17-0.51). Receipt of auto-HCT was not associated with OS (HR, 0.69; 95% CI, 0.41-1.16; P = .16) but was associated with MIPI intermediate (HR, 5.7; 95% CI, 2.5-13.2; P < .01) and high (HR, 10.8; 95% CI, 4.7-24.9; P < .01) scores. We report outcomes in a large cohort of patients with blastoid/pleomorphic variant MCL. For eligible patients, receipt of auto-HCT after induction was associated with improved PFS but not OS. Higher MIPI score and auto-HCT ineligibility were associated with worse survival.

Skin Involvement by Hematological Neoplasms with Blastic Morphology: Lymphoblastic Lymphoma, Blastoid Variant of Mantle Cell Lymphoma and Differential Diagnoses.

Hematological neoplasms sharing a blastic morphology may involve the skin. The skin may be either the primary site of occurrence of hematological malignancies with blastic features or cutaneous lesions are the first manifestation of an underlying systemic malignancy. The assessment of skin biopsies of hematological neoplasms with blastic features poses diagnostic problems and requires expert hematopathologists considering a wide range of differential diagnoses. The precise diagnosis of diseases sharing blastic features but with different outcomes and requiring distinct therapies is essential for patient management. The present paper mainly focuses on cutaneous involvement of the blastoid variant of mantle cell lymphoma and lymphoblastic lymphoma of B-cell or T-cell origin. The relevant literature has been reviewed and the clinical aspects, pathological features, prognosis, and therapy of both blastoid mantle cell lymphoma and lymphoblastic lymphoma involving the skin are discussed. A focus on other hematological entities with blastic features, which may involve the skin, to be taken into consideration in differential diagnosis is also given.

Blastoid and Pleomorphic Mantle Cell Lymphoma Demonstrate Distinct Clinicopathologic and Genetic Features.

The blastoid (B) and pleomorphic (P) variants of mantle cell lymphoma (MCL) are associated with aggressive clinical behavior. In this study, we collected 102 cases of B-MCL and P-MCL from untreated patients. We reviewed clinical data, analyzed morphologic features using an image analysis tool (ImageJ) and we assessed mutational and gene expression profiles. The chromatin pattern of lymphoma cells was assessed quantitatively by the pixel value. Cases of B-MCL showed a greater median pixel value with lower variation compared with P-MCL, indicating a homogeneously euchromatin-rich pattern in B-MCL. In addition, the Feret diameter of the nuclei was significantly smaller (median 6.92 vs. 8.49µm per nucleus, P <0.001) and had a lesser degree of variation in B-MCL compared with P-MCL, indicating that B-MCL cells have smaller cells with a more monomorphic appearance. B-MCL showed a significantly higher median Ki-67 proliferation rate (60% vs. 40%, P =0.003), and affected patients had poorer overall survival compared with those with P-MCL (median overall survival: 3.1 vs. 8.8y, respectively, P =0.038). NOTCH1 mutation was significantly more frequent in B-MCL compared with P-MCL (33% and 0%, respectively, P =0.004). Gene expression profiling showed 14 genes overexpressed in B-MCL cases and gene set enrichment assay for the overexpressed genes showed significant enrichment in the cell cycle and mitotic transition pathways. We also report a subset of MCL cases that has blastoid chromatin but a higher degree of pleomorphism in nuclear size and shape, designated here as hybrid MCL. Hybrid MCL cases had a similar Ki-67 proliferation rate, mutation profile, and clinical outcome to B-MCL and distinct from P-MCL. In summary, these data suggest biological differences between B-MCL and P-MCL cases justifying their separate designation when possible.

Role of Morphology in the Diagnosis of Acute Leukemias: Systematic Review

AbstractThe role of hematopathologists in the diagnosis of acute leukemia (AL) starts with the morphological examination of either peripheral blood smear or bone marrow. The morphological hallmark for the myeloblast includes “Auer rods” and “Phi bodies.” The addition of cytochemical stains such as myeloperoxidase, Sudan Black B, periodic acid-Schiff stain, nonspecific esterase, and Perls' stain acts as an important adjunct to the morphological classification in the resource-constrained settings. The recent World Health Organization classification still endorses the utility of morphology which requires the presence of either ≥ 20% lymphoblasts or myeloblasts/or its equivalents (monoblasts, promonocytes, or megakaryoblasts) and integrates it with the clinical features, immunophenotyping (IP), and molecular genetics for making the diagnosis of AL. Morphology can give clue to the specific diagnosis of acute myeloid leukemia (AML) with t(8:21), t(15:17), t(16:16), or inv(16) and this diagnosis can be made irrespective of blasts count if such translocations are demonstrated by molecular tests. There are some interesting findings such as blasts with “hand-mirror” morphology, nuclear cleavage, prominent cytoplasmic vacuoles, pseudo-Chediak-Higashi granules, cup-like nucleus, and other dysplastic features helping in differentiating lymphoid and myeloid leukemias. Transient abnormal myelopoiesis in Down syndrome and hypoplastic AL can be picked up on morphological examination. Bone marrow biopsy would be greatly beneficial and complementary to aspirate smears and is required for diagnosing exact cellularity, topography of cells, dyspoiesis, myelonecrosis, gelatinous marrow transformation, myelofibrosis, and IP can be performed using immunohistochemistry. Morphological examination in AL is not only helpful for diagnosis but also useful for predicting the prognosis in posttherapy cases, AML with myelodysplasia-related changes, therapy-related myeloid neoplasms, and mixed phenotype AL. Hematogones, blastoid mantle cell lymphoma, high grade B cell lymphoid with blastoid morphology, Burkitt leukemia, prolymphocytes in prolymphocytic leukemia, hairy cell leukemia variant, plasmablasts especially in plasmablastic leukemia, or plasma cell leukemia can mimic AL and IP is useful in these situations. Hence, morphology should be considered as a kind of “gold-standard” starting point for the analysis of AL cases. Morphological examination cannot be replaced and advanced tests cannot be used as surrogate for morphology.

Blastoid B-Cell Neoplasms: Diagnostic Challenges and Solutions.

Blastoid B-cell neoplasms mainly include B-lymphoblastic leukemia/lymphoma (B-ALL), blastoid mantle cell lymphoma, and high-grade B-cell lymphoma with blastoid morphologic features (blastoid HGBL). Distinguishing blastoid HGBL from B-ALL can be challenging and we previously developed six-point flow cytometry-focused and three-point immunohistochemistry-focused scoring systems to aid in differential diagnosis. However, the six-point scoring system was derived from bone marrow cases and occasional cases may have a misleading score using either system. In this study, we assessed 121 cases of blastoid-HGBL (37 BM and 84 extramedullary) to validate the six-point scoring system in all tissue types and to further compare the two scoring systems. Compared with 47 B-ALL cases enriched for CD34-negative neoplasm, the 121 blastoid-HGBL cases showed distinctive pathologic features. The six-point scoring system showed a sensitivity of 100%. A comparison of the two scoring systems in blastoid HGBL (n = 64) and B-ALL (n = 37) showed a concordance score rate of 88%. Thirteen cases showed misleading scores, including five HGBL and eight B-ALL, and the diagnosis was further validated by gene transcriptome profiling. Twelve of thirteen cases had discordant scores between the two scoring systems. Simultaneous employment of both scoring systems improved the accuracy of classification of blastoid B-cell neoplasms to 99%. In conclusion, the previously defined six-point scoring system showed an excellent performance regardless of the tissue origin. Using both scoring systems together improves the accuracy of classification of blastoid B-cell neoplasms. Cases with discordant scores between the two scoring systems were extremely challenging neoplasms and classification required correlation with all available clinical and genetic features.

The Therapeutic Synergy of Selinexor and Venetoclax in Mantle Cell Lymphoma Through Induction of DNA Damage and Perturbation of the DNA Damage Response.

Introduction: Mantle cell lymphoma (MCL) can be stratified into blastoid and classical subtypes based on morphological features, with the former subtype having a poorer prognosis. Despite recent advances in targeted approaches, including multiple bruton tyrosine kinase inhibitors which yield impressive clinical responses and improve prognoses, MCL remains an incurable disease with frequent relapses. Additional therapeutic interventions are therefore unmet medical needs for the management of patients with MCL. Methods: Cell viability and apoptosis assays were employed to analyze the therapeutic interaction of venetoclax combined with selinexor in MCL cells. Western blot was used to investigate the potential mechanism of action for the synergy of venetoclax in combination with selinexor in MCL cells. Results: In this study, we revealed that both blastoid and classical MCL cells were vulnerable to the cytotoxic effects of selinexor, a well-established XPO1 inhibitor, manifested by loss of cell viability and induction of cell apoptosis. Moreover, our data indicated that the addition of venetoclax to selinexor showed synergistically decreased cell viabilities and increased cell deaths in blastoid and classical MCL cells compared to each single drug treatment. Either selinexor or venetoclax treatment alone decreased MCL1 expressions and increased BAX levels in MCL cells, and these effects were further enhanced by their combined regimen. Mechanistically, our findings demonstrated that induction of DNA damage and inactivation of DNA damage response were involved in the synergistic interaction of the drug combination regimen. Conclusion: Collectively, this study might provide a potential attractive therapy option for the treatment of MCL. However, the conclusion needs additional experimental validation in in vivo models and clinical evaluations are mandatory.

Genetic and Prognostic Analysis in Blastoid and Pleomorphic Mantle Cell Lymphoma: A Multicenter Analysis in China

Blastoid and pleomorphic mantle cell lymphoma (B/PMCL), which are characterized by more highly aggressive features and an unfavorable outcome, are still a diagnostic and therapeutic challenge in MCL. In this study, we aimed to integrated analysis of clinical, genomic characteristics and treatment options of patients with blastoid/pleomorphic mantle cell lymphoma in China from multicenter. Second generation sequencing was performed in evaluable biopsy specimens. Seventy-four patients with blastoid (n=43) and pleomorphic (n=31) were included in the analysis. Median age of the cohort was 60.0 years with a male-to-female ratio of 2.89:1. 3-year progression free survival (PFS) and overall survival (OS) rates were 37.6% and 46.0%, respectively. The most common gene mutations in blastoid/pleomorphic MCL were TP53, ATM, NOTCH1, NOTCH2, NSD2, SMARCA4, CREBBP, KMT2D, FAT1, TRAF2. Progression of disease within 12 months (POD12) can distinguish the worst prognosis in blastoid and pleomorphic variants. Which carried a distinct mutation profile (TP53, SMARCA4, NSD2, NOTCH2, KMT2D, PTPRD, CREBBP and CDKN2A mutations) compared with non-POD12 patients. Gene with POD≤12 was enriched in BCR signaling while gene with POD>12 were enriched in TRAF3-dependent IRF activation pathway. First-line high dose cytarabine exposure obtained survival benefits in these population, and BTKi-combined treatment in front-line had somewhat improvement in survival with no significant difference in statistic. In conclusion, B/P MCL have inferior outcomes and distinct genomic profile, patients with POD12 display a distinct mutation profile and worst prognosis, new therapeutic drugs and clinical trials need to be further explored in B/P MCL. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

A Rare Case of Therapy Related Monoblastic Leukemia with t(8;16)(p11.2;p13.3)/KAT6A-CREBBP Fusion and Hemophagocytosis

Abstract Introduction/Objective Therapy related leukemias are often myeloid and occur as a late complication of cytotoxic therapy or radiotherapy. Most common etiologies are alkylating agents and topoisomerase II inhibitors leading to inaccurate base pairing and chromosomal breakages resulting in complex karyotypes. We describe an extremely rare case of therapy related monobalstic leukemia with t(8;16)(p11.2;p13.3)/KAT6A-CREBBP Fusion and hemophagocytosis. Methods/Case Report An 81-year-old female with history of mixed cellularity Hodgkin’s lymphoma status post chemotherapy with AVD (Adriamycin, Vinblastine and Dacarbazine) and in remission presented with a complaint of newly developed skin rash on her chest. Punch biopsy showed a diffuse infiltrate of blastoid mononuclear cells with a component of monocytic differentiation present throughout the dermis. Complete blood count revealed bicytopenia (Hemoglobin 8.4 g/dl, platelets 32 x 109 per liter) and peripheral blood smear examination showed 54% blasts. Bone marrow biopsy was remarkable for infiltration by 79.2% blasts with monocytic differentiation and prominent hemophagocytosis. Immunophenotypic analysis was notable for weak positivity for p53 and a Ki67 proliferation index of 20%. These results led to the diagnosis of monobasic leukemia with hemophagocytosis. Cytogenetic analysis was abnormal with 19 out of 20 metaphases showing t(8;16)(p11.2;p13.3). Interestingly, FISH revealed the rare KAT6A- CREBBP fusion gene. The patient was hospitalized for induction chemotherapy and started on Decitabine. Her hospital course was complicated with acute kidney injury and pulmonary edema with rapid deterioration along with persistent elevation of blasts in the blood. The patient opted for hospice due to lack of improvement and died thereafter. Results (if a Case Study enter NA) NA. Conclusion AML with t(8,16) is an extremely rare entity accounting for 0.2 to 0.4% of AML cases. AML with t(8,16)/KAT6-CREBBP is frequently associated with monocytic or myelomonocytic differentiation, leukemia cutis and hemophagocytosis. While spontaneous remission can occur in a subset of neonatal t(8;16)(p11.2;p13.3), the majority of cases are therapy-related and carry a poor prognosis as seen in our patient.

Hematogones: The Supreme Mimicker and a Cytomorphological Confounder in Acute Lymphoblastic Leukemia.

Objective B-lymphocyte progenitors, namely the hematogones (HGs), may pose problems in morphological assessment of bone marrow, not only during the diagnostic workup but also while evaluating bone marrow for remission status following chemotherapy. Here, we describe a series of 12 cases of acute lymphoblastic leukemia (ALL) that included both B-ALL and T-ALL cases, which were evaluated for remission status and revealed blast-like mononuclear cells in bone marrow in the range of 6 to 26%, which on immunophenotypic analysis turned out to be HGs. Materials and Methods This is a case series of 12 ALL cases who were undergoing treatment at the Army Hospital (Referral and Research), New Delhi. All these cases were under workup for post-induction status (day 28) and to check for suspected ALL relapse. Bone marrow aspirate (BMA), biopsy, and immunophenotyping were performed. Multicolored flow cytometry was performed using CD10, CD20, CD22, CD34, CD19, and CD38 antibodies panel. Results BMA assessment of 12 cases revealed a maximum of 26% blastoid cells and a minimum of up to 6%, raising the suspicion of hematological relapse. However, on clinical assessment, these patients were well preserved, with preserved peripheral counts. Hence, marrow aspirates were subjected to flow cytometry using the CD markers panel, as discussed above, which revealed HGs. These cases were followed by minimal residual disease (MRD) analysis that revealed MRD-negative status, further confirming our findings. Conclusion This case series highlights the importance of morphology and bone marrow immunophenotyping in unveiling the diagnostic dilemma in post-induction ALL patients.

AML-479 An Atypical Cause for Hearing Loss and Syncope: Leukemia Cutis of the Ear Secondary to Acute Myelomonocytic Leukemia

Leukemia cutis is the invasion of leukemic cells into the skin, resulting in identifiable cutaneous lesions. Leukemia cutis is associated with decreased overall survival and may signify the need for more intensive treatment of leukemia. Herein, we present a case of a patient who presented with syncope and hearing loss and was found to have leukemia cutis in his ear. A 42-year-old man with a past medical history of acute myelomonocytic leukemia in remission presented after an unwitnessed fall. He experienced hearing loss from the left ear for two weeks prior to presentation. His oncologic history of acute myelomonocytic leukemia was intermediate risk, NPM1 positive, FLT3 negative, and TKD positive; he received 7 + 3 induction chemotherapy two years prior, followed by high-dose cytarabine (HIDAC), and then maintenance midostaurin. His physical exam was notable for left sided ptosis and facial droop. His laboratory findings were notable for mild leukocytosis with neutrophilia. A CT scan of his head showed a large infiltrative mass, 6 cm by 5 cm by 10 cm, in the left skull base. Pathology demonstrated clusters of atypical monocytic and blastoid cells with irregular nuclei consistent with leukemic cutis. The blastoid cells were positive for CD33, CD4, and CD68 and negative for CD34 and MPO. He experienced acute worsening of vision, and ultimately blindness, over one week. He was evaluated by ophthalmology who performed a dilated fundus exam with findings of retinal hemorrhages at varying levels consistent with leukemic retinopathy. He experienced severe agitation and delirium as a result of losing his vision and hearing. His family ultimately decided to pursue comfort care, and he was discharged to inpatient hospice. Leukemia cutis is an extramedullary manifestation of leukemia and can commonly be confused with other cutaneous lesions. The diagnosis of leukemia cutis requires biopsy. It most commonly occurs in acute myeloid leukemia and typically presents with papules or nodules. The rapid progression of our patient's visual loss and hearing loss highlights the acuity of this manifestation of leukemia and the need for urgent treatment. Further studies on leukemia cutis are warranted to elucidate this aggressive malignancy.

HOW I TREAT DOUBLE-HIT LYMPHMOMA AND HGBL, NOS

The new world health organization (WHO) classification on lymphoid neoplasms, the WHO-HAEM5, renames the former group that double-hit lymphomas were in as “diffuse large B-cell lymphoma/high-grade B-cell lymphoma with MYC and BCL2 rearrangements (DLBCL/HGBL-MYC/BCL2)”. This is mainly to highlight that the presence of MYC and BCL2 rearrangements form a unique phenotype, different than the MYC and BCL6 rearrangements (present in the former classification). Those lymphomas are composed of large or intermediate or blastoid cells, with aggressive clinical course and tendency to be resistant to standard chemotherapy. It's a group ideal for new therapies, such as the bispecifics and CAR T-cells, but lack data to support this since are underrepresented in clinical trials. Retrospective studies, with its inherit bias, consistently points to worst prognosis and poor outcomes with standard RCHOP treatment. How to best approach this hard-to-treat lymphoma is still a matter of debate. Roughly 65% of patients with DLBCL are cure with 6 cycles of RCHOP. When considering this regimen for HGBL, event-free survival (EFS) has been reported as low as 20% in 3 years. More intensive regimens, like R-DA-EPOCH and R-CODOX/M-IVAC, could increase this response, based on retrospective studies, with EFS 3y close to 80%. The role of autologous transplant as consolidation is controversial, and it's not routinely indicated. However, there are data that patients treated with RCHOP could increase progression-free survival (PFS) with this strategy, perhaps eliminating the difference between more intensive regimens. The lack of a direct comparison in a randomize phase 3 study between RCHOP or more intensive protocols precludes a firm conclusion. In the Alliance/CALGB 50303 study, that compared RCHOP with R-DAEPOCH in patients with DLBCL and PMBCL, there were no differences in 2y PFS between arms. But the number of patients with MYC rearrangement was too small to any conclusion regarding HGBL. Dunleavy et al conducted a phase 2 study with R-DA-EPOCH in 53 patients with MYC-rearranged DLBCL (24 were double-hit). EFS 4y was 71% and overall-survival (OS) 4y was 77%. Although this looks pretty good compared to the historic RCHOP, it's not a randomize study. New therapies have emerged as possible rescue in the relapsed/refractory DLBCL population, a group of patients with a dismal prognosis. The chimeric antigen receptor (CAR) T-cells have become a new standard of care for those patients, when available. Albeit with a small number of patients, the three main products (axi-cell, tisa-cell and liso-cell), used for rescue of DLBCL patients, had shown activity against HGBL. That holds true in latter lines and as a first salvage treatment, as the recent trials comparing with autologous transplant. The zuma-12 is a phase 2 study with axi-cell as first-line of treatment with high-risk DLBCL patients, a population enriched with HGBL. Early reports are impressive, with nearly 80% of complete remissions. However, long term follow-up will be necessary to see with the responses are durable. Bispecifics are other very important players on that field, with the first reports of high activity in high-risk DLBCL, even after CAR T-cell failure. HGBL is an aggressive form of lymphoma, with tendency of a worst prognosis with conventional treatment. Intensive regimens seem to fare better than RCHOP, although with more toxicity and no randomize studies supporting this indication. New treatments, mainly CAR T-cells and bispecifics, are very promising and possibly will became standard of care for such patients but were in the therapy algorithm is still to be decide.

ALL-473 Dilemma of Diagnosing and Treating BPDCN; Case Report With Clinicopathological Correlation

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is an aggressive hematological malignancy with a rare incidence with poor outcome. Usually, it presents by skin infiltration then dissemination and only 10% may present first by bone marrow (BM) infiltration. It has overlapping features with acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) clinically and pathologically, and there are many diseases to be differentially diagnosed from them. There is no consensus for treating BPDCN, but there are some novel therapies that have emerged in the field for treating this group of patients. A case report of 47-year-old diabetic male, presented to the hematology unit of Oncology Center of Mansoura University with a large, elevated scalp mass on the anterior part near the forehead with overlying pressure necrosis of the skin and face edema and with similar lesions on the back. There were enlarged cervical and inguinal lymph nodes. Skin biopsy revealed infiltration by monomorphous medium-sized blastoid cells, with fine chromatin and scanty cytoplasm, pannicular extension, and no detected epidermotropism. Immunohistochemistry revealed diffuse membranous immunoreactivity for CD4, CD56, and BCL2. Ki-67 proliferation index was about 90%. CD117, MPO, CD34, CD20, CD5, CD3, ALK, CD79a, and CD30 showed negative immunoreactivity in the tumor cells. BM examination showed infiltration by 80% large blastoid cells with basophilic cytoplasm and fine chromatin. Multi-color-flowcytometry (MCF) revealed low CD45 expression (located in the blast pocket) and positive CD123, a spectrum of CD56 (moderate to negative), dim CD4, CD43, partial dim CD33, CD38, CD81, and partial CD36 (predominantly negative), and was negative for the rest of the panel. The patient received Hyper-CVAD protocol (cyclophosphamide, vincristine sulfate, doxorubicin hydrochloride, and dexamethasone) and skin lesions showed marvelous response after 1st cycle of chemotherapy. BM and FDG -PET/CT evaluation was free from abnormal cell infiltration. Now he is completing his chemotherapy and planned for allogenic stem cell transplantation (SCT). The diagnosis and management of such cases are challenging at all levels from the beginning of the disease, through the steps of diagnosis and finally in choosing the appropriate treatment protocol. We recommend ALL-based chemotherapy protocols especially Hyper-CVAD then allogenic SCT for better response and overall survival.