Abstract: Thrombotic Thrombocytopenic Purpura (TTP) is a thrombotic microangiopathy syndrome resulting from decrease or absence of “a disintegrin and metalloproteinase with a thrombospondin type 1 motif member 13” (ADAMTS13). TTP has been characterized by the classical pentad of thrombocytopenia, hemolysis, fever, renal injury and neurological deficits, yet the patient may present with any atypical symptom related to microthrombi formation in the microcirculation. Here we present a rare case of a young patient with retrosternal chest pain and myocardial injury as the first manifestation of TTP.

Abstract: The detection of concurrent JAK2V617F and BCR-ABL mutations is uncommon; an incidence of 2.5% is reported in the literature. Scarce data indicate that the coexistence of JAK2V617F mutation and BCR-ABL translocation may denote an adverse prognostic factor for CML. Recently, the occurrence of novel Calreticulin (CALR) mutations in JAK2/MPL unmutated ET or PMF was reported. To our knowledge, no CALR mutations have been described so far in the context of BCR-ABL positive MPNs. We present 3 cases with molecularly defined diagnosis of another type of MPN in addition to Ph+ CML, including one patient with the novel finding of a CALR mutation in conjunction with the BCR-ABLtranslocation, and we infer a possible mechanism for the emergence of a second MPN clone upon treatment of the initial MPN. A 32 yr old female was diagnosed in 1999 with ET on the basis of marked thrombocytosis in the absence of any underlying cause. She was treated with INF-α and subsequently with anagrelide. Six years later (2005) and while the CBC was normal, cytogenetic and molecular studies disclosed the presence of Ph1 chromosome in 4/20 metaphases and BCR-ABL transcripts (7.2% IS, e15a2). Imatinib was initiated and after 3 months CCyR and MMR were achieved. Due to an increasing platelet count one year later, a trephine biopsy was performed that was compatible with ET. Hydroxyurea (HU) was added to treatment. No JAK2V617F mutation was detected. Fifteen years after the initial presentation, a CALR exon 9 mutation was retrospectively detected in all available samples since diagnosis of CML. The mutant allele burden has remained stable during follow-up, while patient being in MR4 with regard to CML. A 50 yr old woman was diagnosed with PV in 1998. Cytogenetic studies were normal and BCR-ABL was undetectable. JAK2V617F homozygous mutation was present on retrospective testing. A complete hematologic remission was achieved with phlebotomy and HU. Ten years later, re-evaluation due to an increasing WBC disclosed the presence of Ph1 chromosome in 20/20 metaphases and BCR-ABL transcripts (38.4% IS, e15a2). Interestingly, JAK2V617F was not detected. After 4 months of treatment with TKI plus HU, a 2-log BCR-ABL reduction was noted, while JAK2V617F was detected again at a heterozygous state. She received sequentially all 3 first available TKIs due to intolerance. Upon TKI treatment for 9 months, CCyR and MMR were achieved in parallel with emergence of JAK2V617F homozygosity. After achieving MR4 for more than 2 years, the TKI was discontinued and, 3 months later, the patient remains in MR4 with persistent JAK2V617F homozygosity. Due to splenomegaly and increased Hct, treatment with HU is continuously required. An 80 yr old female was diagnosed with chronic phase CML [Ph1+, BCR-ABL (35.5% IS, e15a2)]. She achieved mCyR and 1-log reduction of BCR-ABL levels after 6 months on imatinib. Due to imatinib failure, she was switched to nilotinib at 9 months. Two years after initial diagnosis, while CML was in MMR, an increase in Hct and platelets was noticed and JAK2V617F heterozygosity was detected. Retrospective analysis did not reveal JAK2V617F mutation at diagnosis and on the 3-month sample, while low level of mutant V617F allele was detected on the 6-month sample. Increasing levels of mutant versus wild type allele were detected in all subsequent samples. The patient was treated with phlebotomy, HU and ASA in addition to nilotinib. She died 4 years after initial diagnosis from an unrelated cause while in MR4 for CML and complete hematologic remission for PV. Despite these cases seem to be uncommon, they raise intriguing issues regarding the clonal origins of distinct molecular types of MPNs present in the same patient. They may also challenge the traditional hypothesis of evolution of one type of MPN to another. Instead of perceiving clinical and genetic features of second MPN as simple evolution of a precedent MPN, our cases suggest an alternative explanation based on pre-existence of two different MPN clones. Treatment for the initial MPN, especially with highly-efficient targeted agents (like TKIs for Ph+ CML) may facilitate the emergence of a second clone and vice versa. In conclusion, any divergent manifestations in a patient with MPN may warrant further investigation of genetic markers suggestive of an additional MPN entity. A high level of suspicion for the possibility of coexistence Ph+ and Ph- MPN may result in a more comprehensive treatment approach and optimal outcome. Disclosures No relevant conflicts of interest to declare.

Abstract: As conventional microbiological documentation of invasive aspergillosis (IA) is difficult to obtain, serum fungal biomarkers are important adjunctive diagnostic tools. Positivity rates and the kinetic profiles of galactomannan (GM), 1,3-β-D-glucan (BDG) and Aspergillus DNA (PCR) were studied in high-risk patients with hematologic malignancies. GM, BDG and PCR data from serial serum specimens (n = 240) from 93 adult hematology patients with probable (n = 8), possible (n = 25) and no (n = 60) IA were retrospectively analyzed. Positivity rates and sensitivity/specificity/positive/negative predictive values (NPV) of each fungal biomarker alone and in combination were estimated. The three markers were compared head-to-head and correlated with various biochemical, demographic and patient characteristics. The positivity rates for patients with probable/possible/no IA were 88%/8%/0% for GM (X2 = 55, p 〈 0.001), 62%/46%/35% for BDG (X2 = 2.5, p = 0.29), 62%/33%/27% for PCR (X2 = 3.9, p = 0.15), 50%/4%/0% for GM + BDG and GM + PCR (X2 = 31, p 〈 0.001), 50%/8%/22% for BDG + PCR (X2 = 6.5, p = 0.038) and 38%/4%/0% for GM + BDG + PCR (X2 = 21, p 〈 0.001). Higher agreement (76%) and negative correlation (rs = −0.47, p = 0.0017) was found between GM index and PCR Ct values. The sensitivity and NPV was 45–55% and 90–92% when biomarkers assessed alone and increased to 75–90% and 93–97%, respectively when combined. Weak significant correlations were found between GM, PCR and BDG results with renal/liver function markers (r = 0.11–0.57) with most GM+ and PCR+ samples found in the first and second week of clinical assessment, respectively and BDG later on. Different positivity rates, time profiles and performances were found for the three biomarkers advocating the combination of GM with PCR for the early diagnosis of IA, whereas the high NPV of combined biomarkerscould help excluding IA.

Abstract: Data concerning the incidence of invasive aspergillosis (IA) in high-risk patients in Greece are scarce, while the impact of the revised 2020 EORTC/MSGERC consensus criteria definitions on the reported incidence rate of IA remains unknown. A total of 93 adult hematology patients were screened for IA for six months in four tertiary care Greek hospitals. Serial serum specimens (n = 240) the sample was considered negative by PCR were collected twice-weekly and tested for galactomannan (GM) and Aspergillus DNA (PCR) detection. IA was defined according to both the 2008 EORTC/MSG and the 2020 EORTC/MSGERC consensus criteria. Based on the 2008 EORTC/MSG criteria, the incidence rates of probable and possible IA was 9/93 (10%) and 24/93 (26%), respectively, while no proven IA was documented. Acute myeloid leukemia was the most (67%) common underlying disease with most (82%) patients being on antifungal prophylaxis/treatment. Based on the new 2020 EORTC/MSGERC criteria, 2/9 (22%) of probable and 1/24 (4%) of possible cases should be reclassified as possible and probable, respectively. The episodes of probable IA were reduced by 33% when GM alone and 11% when GM + PCR were used as mycological criterion. The incidence rate of IA in hematology patients was 10%. Application of the 2020 EORTC/MSGERC updated criteria results in a reduction in the classification of probable IA particularly when PCR is not available.

Abstract: Background: The currently used prognostic systems for myelodysplastic syndromes (MDS) do not consider the prognostic role of monocytopenia, although monocytes may participate in the prognosis of the disease as part of the host immunity. Aim: We studied the prognostic significance of monocytopenia in patients with MDS registered in the Hellenic National MDS registry. Methods: We analyzed clinicopathological data from patients with MDS recorded in a large retrospective national registry. Patients with MDS/MPN were excluded, while patients treated with allogeneic hematopoietic cell transplantation were censored for overall survival (OS) and leukemia-free survival (LFS). IBM SPSS statistics, version 23.0 (IBM Corporation, North Castle, NY, USA) was used for the analysis of the results. Kaplan-Meier survival analysis and Cox regression analysis were performed for LFS and OS. Results: The study comprised 1719 patients with MDS per the 2008 WHO classification for MDS. The main characteristics of the patients are shown in Table 1. At the time of data cut-off, 818 patients were deceased and the median follow-up for the remaining 901 patients was 23.0 months. The median absolute monocyte count (AMC) was 0.30 x 109/L (0.00 - 0.99 x 109/L). Patients with excess blasts (RAEB1/2) tended to have lower AMCs (median 0.19 versus 0.32 for patients without excess blasts, p 〈 0.0001) and lower AMCs were found in higher IPSS-R categories (very low, 0.37 x 109/L; low, 0.30 x 109/L; intermediate, 0.25 x 109/L; high, 0.16 x 109/L; very high, 0.20 x 109/L) while there was a highly significant difference between lower risk (very low and low) and higher risk (intermediate, high, very high) MDS (0.33 x 109/L vs 0.21 x 109/L, p 〈 0.0001). In univariate analysis, patients with AMCs below 0.2 x 109/L had a median OS of 34.0 months vs 63.0 months for patients with higher AMCs (p 〈 0.0001) with a hazard ratio (HR) for death of 1.57 (95% CI 1.37 - 1.81, p 〈 0.0001). In a multivariate Cox regression model including hemoglobin below 10 g/dL, absolute neutrophil count (ANC) below 1.0 x 109/L, and platelet count below 100 x 109/L (all of them being prognostic for OS in univariate analysis), monocytopenia retained its prognostic significance (HR, 1.16; 95% CI, 1.00 - 1.36, p=0.049). There was a positive correlation between the AMC and the ANC (Pearson Correlation 0.393, p 〈 0.0001). Nevertheless, in a model comprising of AMC and ANC, both variables were independently correlated to OS. Moreover, in a model including AMC below 0.2 x 109/L, the cytogenetic risk score per the IPSS-R, the number of cytopenias, and bone marrow blasts (categorized per the IPSS-R), no additional prognostic impact was found for AMC (HR, 1.01; 95% CI, 0.86 - 1.17; p=0.957). After stratification per the IPSS-R categories, low AMC was prognostic for low OS only in patients with low IPSS-R (median OS, 57 months for patients with low AMC vs 75 months for those with high AMC, p=0.039), but there was no additional prognostic impact after multivariate analysis. Moreover, AMC was prognostic for LFS, since patients with low AMCs ( 〈 0.2 x109/L) had a median LFS of 57.0 months, while the median LFS for patients with higher AMCs was not reached (HR, 2.47, 95% CI, 2.01 - 2.47, p 〈 0.0001). In a Cox regression model including the above stated factors (cytopenias, bone marrow blasts, cytogenetic risk, and AMC), AMC retained its prognostic significance for LFS (HR, 1.27; 95% CI, 1.02 - 1.58; p=0.031). In a subgroup of 162 patients treated with hypomethylating agents (HMAs), monocytopenia was not predictive or response to treatment, but low AMC was correlated to a shorter median progression free survival (27.0 months vs not reached for patients with higher AMC, p=0.001). This correlation was not translated into a survival benefit (survival after HMA initiation, 27.0 vs 28.0 months respectively, log rank p=0.213). Conclusions: Based on a large patient cohort, we found that patients with MDS with excess blasts as well as higher risk patients per the IPSS-R have low AMCs. Moreover, we showed that low AMCs are prognostic of lower OS in univariate analysis and of lower LFS in both univariate and multivariate analysis, highlighting a possible pathogenetic role for AMCs in MDS. Further analysis is needed to define the exact prognostic role of AMC in MDS. Disclosures Pappa: Amgen: Research Funding; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene / GenesisPharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Honoraria, Research Funding; Abbvie: Research Funding; Novartis: Honoraria, Research Funding, Speakers Bureau; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Kotsianidis:Celgene: Research Funding. Symeonidis:MSD: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Research Funding; Tekeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding. Vassilakopoulos:Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; WinMedica: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene / GenesisPharma: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Abstract: Introduction: Less than 5% of patients with MDS present with thrombocytopenia as an isolated abnormality (MDS-IT). There have been few systematic studies on MDS-IT and data regarding its course and prognosis are conflicting. Previous studies have defined MDS-IT based on the IPSS thresholds (Hb ≥10 g/dL; ANC ≥1.8×10 9/L; PLT & lt;100×10 9/L). However, these were developed for prognostic, not diagnostic purposes which means that mild anemia and/or neutropenia might be present concomitantly with "isolated" thrombocytopenia. We aimed to investigate the characteristics, overall survival (OS), and leukemia-free survival (LFS) of patients with MDS-IT. Methods: We identified patients who had PLT & lt;150 ×10 9/L, Hb & gt;13 g/dL (men) or & gt;12 g/dL (women), and ANC ≥1.8 ×10 9/L, registered in the Hellenic National Registry of Myelodysplastic and Hypoplastic Syndromes which includes 2792 patients (analysis cut-off date; July 7, 2016). Patients were divided into 4 groups: group 1 had PLT 149-100 ×10 9/L; group 2, 99-50 ×10 9/L; group 3, & lt;50 ×10 9/L; and group 4, & lt;25 ×10 9/L. We also collected data from the Hellenic National ITP Registry which includes 1317 adult patients with ITP. Results: A total of 77 patients (45 men; 32 women) with MDS-IT were identified (2.9% of total MDS cohort). Of these, 28.6% were classified in group 1; 49.4% in group 2; 14.3% in group 3; and 7.8% in group 4. Median PLT count was 87 ×10 9/L (12-139 ×10 9/L), WBC count 4.6 ×10 9/L, and Hb 13.6 g/dL. Bone marrow (BM) blasts ranged from 0-9% (median, 2%). Median follow-up was 51.0 months (41.6-60.4), during which 15 (19.5%) patients died. AML developed in 9 patients (11.7%). Histologically, MDS with multilineage dysplasia (MLD) was seen in 77.6% whereas MDS with excess blasts (EB) and MDS with single lineage dysplasia (SLD) comprised 10.7% and 11.9% of cases, respectively. Most patients (73.5%) had lower-risk MDS on the IPSS-R (i.e. IPSS-R ≤3.5). Of the 59 patients with cytogenetic data, 83.1% had favorable, 13.5% intermediate, and 3.4% poor risk cytogenetics. Most (40) had a normal karyotype followed by isolated del(20q) (6). All patients with del(20q) showed a characteristic set of clinical features: age & gt;60 years, blasts 0-3%, bilineage (erythroid/megakaryocytic) dysplasia, and increased reticulin fibrosis. There were no significant differences between any of the 4 PLT groups regarding age, sex, IPSS-R, cytogenetics, BM blasts, and histology. Median OS was 109 months (95% CI 103-115) and LFS 108 months (101-115). Our results showed no significant difference in OS (P=0.891) and LFS (P=0.871) between the 4 PLT groups. As compared with total MDS cohort, MDS-IT occurred at younger age (64.7 vs. 72.4 years, P & lt;0.001). In a Kaplan-Meier analysis, patients with MDS-IT had markedly longer OS and LFS than patients in the total MDS cohort, even after adjustment for age, sex, IPSS-R, blasts, and PLT (P=0.013 for OS; P=0.017 for LFS) (Figure 1A). There were no differences in the top causes of death: infection was the commonest cause followed by disease progression and cardiovascular disease. Major bleeding comprised 10.3% of deaths in MDS-IT vs. 12.7% in total MDS cohort (P=0.217). In comparing MDS-IT with ITP, the median age at diagnosis was 66.0 years for MDS-IT and 49.0 years for ITP (P & lt;0.001).MDS-IT was uncommon in patients & lt;50 or & gt;80 years. Its incidence reached a peak between the ages of 70-79 years, whereas ITP occurred at a more constant level over time (Figure 1B). Women predominated in ITP and men in MDS-IT (P=0.007). Overall, ITP was associated with more marked thrombocytopenia than MDS-IT (15.0 ×10 9/L vs. 87.0 ×10 9/L) (P & lt;0.001). Median WBC count was higher in ITP (7.6 ×10 9/L vs. 4.6 ×10 9/L; P & lt;0.001). Median Hb was similar in the 2 groups. Patients with ITP had longer OS than MDS-IT (P & lt;0.001). Conclusions: In one of the largest reported series, we conclude that MDS-IT is associated with MDS-MLD, favorable cytogenetics, lower-risk IPSS-R, high survival rate, and a low risk of AML evolution. Our data suggest that the superior prognosis in MDS-IT than general MDS may have intrinsic genomic underpinnings as survival curves remained unchanged after correcting for age, sex, blasts and IPSS-R. Importantly, no significant differences in OS and LFS were noted between the 4 PLT subgroups, suggesting that the degree of thrombocytopenia does not correlate with mortality in MDS-IT. From the diagnostic standpoint, age & lt;50 or & gt;80 years and PLT & lt;25 ×10 9/L favored a diagnosis of ITP over MDS-IT. Figure 1 Figure 1. Disclosures Viniou: Sandoz: Research Funding; Takeda: Research Funding; Novartis: Honoraria, Research Funding; Sanofi: Research Funding; Janssen: Honoraria, Research Funding; Pfizer: Research Funding; Abbvie: Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; Roche: Research Funding; Astellas: Research Funding; Celgene: Research Funding. Vassilakopoulos: Dr. Reddy's: Research Funding; Amgen: Honoraria, Research Funding; GlaxoSmithKline: Honoraria, Other: Travel; AbbVie: Consultancy, Honoraria; Integris: Honoraria; Pfizer: Research Funding; Roche: Consultancy, Honoraria, Other: Travel; Takeda: Consultancy, Honoraria, Other: Travel, Research Funding; Genesis Pharma: Consultancy, Honoraria, Other: Travel; Merck: Honoraria, Research Funding; Novartis: Consultancy, Honoraria; Karyopharm: Research Funding; AstraZeneca: Honoraria. Hatzimichael: Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; MSD: Consultancy, Honoraria; Gilead: Honoraria; Janssen Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Genesis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria; Pharmathen- Innovis: Honoraria; GSK: Honoraria; Bristol Myersr Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees. Symeonidis: Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi/Genzyme: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Demo: Research Funding; MSD: Consultancy, Research Funding; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; WinMedica: Research Funding; Astellas: Consultancy, Research Funding; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GenesisPharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.