Clinicopathologic features of relapsed CD19(-) B-ALL in CD19-targeted immunotherapy: Biological insights into relapse and LILRB1 as a novel B-cell marker for CD19(-) B lymphoblasts.

INTRODUCTION: The mechanism of relapsed CD19(-) B-ALL after anti-CD19 immunotherapy (Kymriah [CART-19] and blinatumomab) is under active investigation. Our study aims to assess LILRB1 as a novel B-cell marker for detecting CD19(-) B-lymphoblasts and to analyze the clinicopathologic/genetic features of such disease to provide biological insight into relapse. METHODS: Six patients (3 males/3 females, median age of 14 years) with relapsed CD19(-) B-ALL were analyzed for cytogenetic/genetic profile and immunophenotype. RESULTS: CD19(-) B-ALL emerged after an interval of 5.8 months following anti-CD19 therapy. Five of six patients had B-cell aplasia, indicative of a persistent effect of CART or blinatumomab at relapse. Importantly, LILRB1 was variably expressed on CD19(-) and CD19(+) B lymphoblasts, strong on CD34(+) lymphoblasts and dim/partial on CD34(-) lymphoblasts. Three of six patients with paired B-ALL samples (pre- and post-anti-CD19 therapy) carried complex and different cytogenetic abnormalities, either as completely different or sharing a subset of cytogenetic abnormalities. CONCLUSION: LILRB1 can be used as a novel B-cell marker to identify CD19(-) B lymphoblasts. The emergence of CD19(-) B-ALL appears to be associated with complex cytogenetic evolutions. The mechanism of CD19(-) B-ALL relapse under anti-CD19 immune pressure remains to be explored by comprehensive molecular studies.

Prognostic impact of micromegakaryocytes in primary myelodysplastic syndromes.

Micromegakaryocytes (microMKs) are considered a myelodysplastic feature of myeloid neoplasms in adults, with an adverse prognosis connotation. However, this notion in MDS has not been well proved. In our cohort of 287 MDS, patients with microMKs showed lower overall survival (OS) (HR, 2.12; 95% CI, 1.47-3.06; p = 0.000036) and higher risk of acute myeloid leukemia (AML) evolution (HR, 4.8; 95% CI, 2.9-11.01; p = 0.00021). Results were validated with an independent cohort. In multivariate analysis, the presence of microMKs maintained its independent association with OS (HR, 1.54, 95% CI, 1.13-2.1, p = 0.0059) and AML transformation (HR, 2.28, 95% CI, 1.2-4.4, p = 0.014). Moreover, by adding 1 point to the IPSS-R score in patients with microMKs, we improved the IPSS-R accuracy. Interestingly, adding that 1-point, 29% of intermediate IPSS-R risk group patients were upgraded to the high-risk group. In summary, we confirmed that the presence of microMKs implies worse outcomes in MDS and suggested a modification improving IPSS-R.

Is acute lymphoblastic leukemia with mature B-cell phenotype and KMT2A rearrangements a new entity? A systematic review and meta-analysis.

The association between mature B-cell phenotype and KMT2A rearrangements in acute lymphoblastic leukemia is a very rare finding. It identifies a group of patients with similar clinical and biological characteristics that clearly differs from the entity B-cell lymphoblastic leukemia/lymphoma with t(v;11q23)/KMT2A-rearranged, which typically presents an immature pro B-cell phenotype. We describe the clinical-biological characteristics and disease outcome of three pediatric ALL patients with these features treated at our institution, and review 28 cases described in the literature. Most cases occur in children under 2 years-old, presenting a mature B-cell phenotype that uniformly expresses cytoplasmic and surface IgM with lambda light chain restriction, with heterogeneous co-expression of immaturity antigens. Patients do not have MYC rearrangements and all show KMT2A abnormalities, with 76% presenting t(9;11)(p21;q23)/MLLT3-KMT2A. These patients have an unfavorable clinical outcome and a 48% relapse rate. In-depth knowledge of this disease entity is needed to improve outcome.

Dichotomization of the new revised international prognostic scoring system for a better clinical stratification of patients with myelodysplastic syndromes.

In clinical practice, patients with myelodysplastic syndromes (MDS) are usually classified in low or high-risk groups to take therapeutic decisions, conservative for low-risk, whereas active for high-risk. Nevertheless, in the Revised International Prognostic Scoring System (IPSS-R) is not well stated which patients are low or high-risk. This study was aimed to ascertain in 364 MDS patients which IPSS-R threshold better dichotomized in low vs. high-risk. The best dichotomization was obtained with an IPSS-R cut-point of 3. Accordingly, 68% patients were classified as low-risk (median OS, 61.3 months) and 32% as high-risk MDS (median OS, 13.9 months) (p < .001). Interestingly, the intermediate IPSS-R risk patients presented an OS more related to the high IPSS-R than to the low IPSS-R risk group. In conclusion, an IPSS-R cut-point of 3 led to a meaningful stratification in low and high-risk that can be helpful for the clinical management of MDS patients.

Autoimmune disorders are common in myelodysplastic syndrome patients and confer an adverse impact on outcomes.

The coexistence of autoimmune disorders (AD) in patients with myelodysplastic syndrome (MDS) or chronic myelomonocytic leukemia (CMML) has been widely recognized, although with distinct results regarding their prevalence and impact on the outcomes of the underlying hematological process. This study was aimed to analyze the prevalence, clinical characteristics, and outcomes of MDS with AD in a series of 142 patients diagnosed with MDS and CMML. AD was ascertained by both the presence of clinical symptoms or compatible serological tests. In total, 48% patients were diagnosed as having AD, being hypothyroidism the most commonly reported clinical AD (8%) and antinuclear antibodies the most frequent serological parameter identified (23.2%). The presence of AD was associated with female gender, lower hemoglobin levels, and higher IPSS-R. Overall survival for patients with AD was inferior to those with no AD (69 vs. 88% at 30 months; HR 2.75, P = 0.008). Notably, clinical but not isolated immune serological parameters had an impact on the outcomes of patients with AD. Finally, in a multivariate analysis, the presence of AD (HR 2.26) along with disease risk categories (very low and low vs. intermediate, high, and very high IPSS-R; HR 4.62) retained their independent prognostic value (P < 0.001). In conclusion, AD are prevalent in MDS and CMML patients and have prognostic implications, especially in lower-risk MDS patients.

Trisomy 8, a Cytogenetic Abnormality in Myelodysplastic Syndromes, Is Constitutional or Not?

Isolated trisomy 8 is not considered presumptive evidence of myelodysplastic syndrome (MDS) in cases without minimal morphological criteria. One reason given is that trisomy 8 (+8) can be found as a constitutional mosaicism (cT8M). We tried to clarify the incidence of cT8M in myeloid neoplasms, specifically in MDS, and the diagnostic value of isolated +8 in MDS. Twenty-two MDS and 10 other myeloid neoplasms carrying +8 were studied. Trisomy 8 was determined in peripheral blood by conventional cytogenetics (CC) and on granulocytes, CD3+ lymphocytes and oral mucosa cells by fluorescence in situ hybridization (FISH). In peripheral blood CC, +8 was seen in 4/32 patients. By FISH, only one patient with chronic myelomonocytic leukemia showed +8 in all cell samples and was interpreted as a cT8M. In our series +8 was acquired in all MDS. Probably, once discarded cT8M by FISH from CD3+ lymphocytes and non-hematological cells, +8 should be considered with enough evidence to MDS.

Single nucleotide polymorphism array karyotyping: a diagnostic and prognostic tool in myelodysplastic syndromes with unsuccessful conventional cytogenetic testing.

Cytogenetic aberrations identified by metaphase cytogenetics (MC) have diagnostic, prognostic, and therapeutic implications in myelodysplastic syndromes (MDS). However, in some MDS patients MC study is unsuccesful. Single nucleotide polymorphism array (SNP-A) based karyotyping could be helpful in these cases. We performed SNP-A in 62 samples from bone marrow or peripheral blood of primary MDS with an unsuccessful MC study. SNP-A analysis enabled the detection of aberrations in 31 (50%) patients. We used the copy number alteration information to apply the International Prognostic Scoring System (IPSS) and we observed differences in survival between the low/intermediate-1 and intermediate-2/high risk patients. We also saw differences in survival between very low/low/intermediate and the high/very high patients when we applied the revised IPSS (IPSS-R). In conclusion, SNP-A can be used successfully in PB samples and the identification of CNA by SNP-A improve the diagnostic and prognostic evaluation of this group of MDS patients.

Prognostic value of trisomy 8 as a single anomaly and the influence of additional cytogenetic aberrations in primary myelodysplastic syndromes.

Trisomy 8 is the most common chromosomal gain in myelodysplastic syndromes (MDS), however, little is known about the features of MDS with isolated trisomy 8 and the influence of additional cytogenetic aberrations. We determined the characteristics and prognostic factors of 72 patients with trisomy 8 as a single anomaly and analysed also the impact of other aberrations added to trisomy 8 in another 62 patients. According to our study, MDS with isolated trisomy 8 was more frequent in men, with more than one cytopenia in most patients (62%) and having about 4% bone marrow blasts. The multivariate analysis demonstrated that platelet count and percentage bone marrow blasts had the strongest impact on overall survival (OS). The median OS for isolated trisomy 8, trisomy 8 plus one aberration (tr8 + 1), plus two (tr8 + 2) and plus three or more aberrations (tr8 + ≥3) was 34·3, 40, 23·4 and 5·8 months, respectively (P < 0·001). Trisomy 8 confers a poorer prognosis than a normal karyotype in MDS patients with ≥5% bone marrow blasts. This study supports the view that MDS with isolated trisomy 8 should be included in the intermediate cytogenetic risk group.

Intermediate dose of nonpegylated liposomal doxorubicin combination (R-CMyOP) as first line chemotherapy for frail elderly patients with aggressive lymphoma.

Doxorubicin-containing chemotherapy is the standard regimen for elderly patients with aggressive lymphoma. However, many of them cannot receive it due to severe associated comorbidities. Toxicity and efficacy of intermediate doses of nonpegylated liposomal doxorubicin (NPLD) in modified-CHOP regimen ± Rituximab were prospectively analyzed in 35 frail elderly patients (median age: 76 years) with previously untreated aggressive lymphoma with one or more severe comorbidities. NPLD at intermediate doses (30mg/m(2)) is effective and well tolerated in these patients. In addition, NT-proBNP levels > 900ng/ml at diagnosis have demonstrated to be a good predictor for OS and PFS in this cohort of patients.

Successful dexrazoxane treatment of a potentially severe extravasation of concentrated doxorubicin.

Dexrazoxane is now authorized for the treatment of anthracycline extravasations. Several clinical cases of doxorubicin extravasation treated with dexrazoxane have been reported to date, but detailed cases have not been published. We report a case of a successful dexrazoxane treatment for a potentially severe extravasation of concentrated doxorubicin. We also describe objective outcome of this treatment, drug tolerance to dexrazoxane and long follow-up. A 29-year-old man diagnosed with Hodgkin's lymphoma was prescribed a regimen including 90 mg of doxorubicin in a 50 ml infusion using a reduced occlusion infusion pump. After this infusion, the patient complained of pain around the site of injection and presented a 10x6-cm swollen area with erythema and inflammation. A significant portion of doxorubicin was extravasated. Dexrazoxane was prescribed as an antidote. Side effects of dexrazoxane were restricted to reversible hematological toxicity, nausea, and vomiting. The next day, the inflammation of the extravasation area was reduced. On day 7, a painless mild induration in the extravasated area was the only remaining sign of the extravasation. On day 40, an arm nuclear magnetic resonance image showed no focal injuries. At 6-month follow-up, the patient has no sequelae. The two risk factors that could have increased the severity of the extravasation are the use of an infusion pump and the high drug concentration. Dexrazoxane proved to be effective and moderately well tolerated. A dexrazoxane stock in oncological facilities could help to promptly handle emergencies like this. Anthracyclines can be administered using reduced occlusion infusion pumps, but it seems preferable to always administer a free-running infusion to minimize accidents like this one.

Postpolycythaemic myelofibrosis: frequency and risk factors for this complication in 116 patients.

Postpolycythaemic myelofibrosis (PPMF) is a known complication of polycythaemia vera (PV) but information regarding its incidence and predisposing factors is not well defined. In 116 subjects consecutively diagnosed with PV in a single institution (median age 62 years, range: 20-88), the probability of PPMF was analysed by the Kaplan-Meier method, followed by the log-rank test. With a mean follow-up of 8 years (95% confidence interval: 6.6-9), 17 patients had evolved into PPMF (15%). The probability of evolution to PPMF was 16% at 10 years and 34% at 15 years. Age, gender, spleen size, leucocytosis, thrombocytosis or cytoreductive treatment were not associated with an increased risk of PPMF. The actuarial probability of PPMF at 15 years was higher in those patients presenting at diagnosis with endogenous megakaryocytic colony formation (59% when present versus 10% when absent, P = 0.03), an elevated serum lactate dehydrogenase (LDH) level (69% vs. 23% in patients with normal LDH, P = 0.04), and in those who were heterozygous for the JAK2 V617F mutation (55% vs. 17% in heterozygotes, P = 0.04). In conclusion, PPMF is a frequent complication in PV patients at 15 years with the risk being higher in patients with increased LDH, endogenous megakaryocytic colony formation or a high JAK2 V617F allele burden.