Molecular annotation of extramedullary acute myeloid leukemia identifies high prevalence of targetable mutations.

BACKGROUND: Genomic landscape of extramedullary acute myeloid leukemia (EM-AML), including myeloid sarcoma (MS) and leukemia cutis (LC), is not well characterized. The potential utility of next-generation sequencing (NGS) using EM tissue is not established. METHODS: In this multicenter retrospective study, clinical and NGS data were collected on patients with EM-AML. All statistical analyses were performed in SPSS Statistics (v 26). RESULTS: Our study included 58 patients with EM-AML. The median age at diagnosis was 62 years; 59% of patients had MS and 33% had LC. EM-AML was isolated (i.e., without blood or marrow involvement) in 31% and was first noted at relapse in 60% of patients. Median overall survival in our cohort was 18.2 months overall, with 19.1 months and 11.6 months in the newly diagnosed and the relapsed/refractory patients, respectively. At least one targetable or potentially targetable alteration was present in 52% of patients with EM-site NGS, with 26% IDH1, 21% NPM1, 11% IDH2, 6% FLT3, and 13% KMT2A-PTD. Mutations in IDH1 were significantly more prevalent on NGS from EM tissue than non-EM (blood or marrow) samples (26% vs. 3%; p = .030). Three of four patients treated with IDH inhibitors based on EM-site NGS experienced a complete response. CONCLUSIONS: Targetable mutations are frequent in EM-AML and EM-site NGS is warranted for selecting potential targeted therapies for patients with EM-AML.

Clonotypic VDJ rearrangements in Mixed Phenotype Acute Leukemia can be Successfully Utilized to Track Minimal Residual Disease (MRD).

INTRODUCTION: Multiplex polymerase chain reaction (PCR) and next-generation sequencing (NGS) can both be used to identify a neoplastic clonotype by targeting CDR3 and assessing rearrangements in IgH, IgK, IgL, TCR-ß, and TCR-gamma loci. The clonotypic sequence can be robustly used to track minimal residual disease (MRD). The ability to track MRD by NGS in mixed phenotype acute leukemia (MPAL) is unknown and warrants investigation. METHODS: Institutional Review Board (IRB) approval was obtained. Central Moffitt Cancer Center (MCC) database was searched to locate any patients with MPAL from over 600,000 entries. Patient charts were manually curated to identify those with clonoSEQ data, and clinical data was procured from the electronic medical record (EMR). RESULTS: Twenty-nine patients with MPAL were identified. Only 2 patients with clonoSEQ testing were found. Both demonstrated a B/myeloid phenotype, and both were bilineal. NGS (clonoSEQ) identified 4 dominant (IGH) (patient A; 8/2019) and 2 dominant sequences (patient B; 10/2019), respectively. In both patients, clonoSEQ testing successfully tracked minimal residual disease and mirrored clinical disease burden. CONCLUSIONS: This report is the first to confirm the utility of NGS-based MRD tracking in patients with MPAL and shows increased sensitivity of NGS over MRD flow cytometry.

Sclerotic marginal zone lymphoma: A case report.

BACKGROUND: Marginal zone lymphoma (MZL) is an indolent non-Hodgkin B cell lymphoma with various architectural pattern including perifollicular, follicular colonization, nodular, micronodular, and diffuse patterns. A sclerotic variant has not been previously reported and represents a diagnostic pitfall. CASE SUMMARY: A 66-year-old male developed left upper extremity swelling. Chest computed tomography (CT) in September 2020 showed 14 cm mass in left axilla. Needle core biopsy of axillary lymph node showed sclerotic tissue with atypical B lymphoid infiltrate but was non-diagnostic. Excisional biopsy was performed for diagnosis and showed extensive fibrosis and minor component of infiltrating B cells. Flow cytometry showed a small population of CD5-, CD10-, kappa restricted B cells. Monoclonal immunoglobulin heavy chain and light chain gene rearrangement were identified. Upon being diagnosed with MZL, patient was treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone and achieved complete remission by positron emission tomography/CT. CONCLUSION: This is an important case report because by morphology this case could have easily been overlooked as non-specific fibrosis with chronic inflammation representing a significant diagnostic pitfall. Moreover, this constitutes a new architectural pattern. While sclerotic lymphomas have rarely been described (often misdiagnosed as retroperitoneal fibrosis), we do not know of any cases describing this architectural presentation of MZL.

Sex Disparities in Myelodysplastic Syndromes: Genotype, Phenotype, and Outcomes.

Introduction/Background The impact of biological sex on the clinical phenotype, genotype, and outcomes among patients with MDS is not well characterized. Materials and Methods We retrospectively reviewed the clinical and genomic data from male and female patients included in our institutional MDS database at Moffitt Cancer Center. Results Among 4580 patients with MDS, 2922 (66%) were men and 1658 (34%) were women. Women were younger (mean age 66.5 vs. 69 years for men, P < .001) at diagnosis. There were more Hispanic/black women than men (9% vs. 5%, P =<.001). Women had lower hemoglobin and higher platelet counts than men. More women had del 5q/monosomy 5 abnormalities compared to men (P =<.001). Therapy related MDS were more common in women than men (25% vs.17%, P=<.001). On assessment of molecular profile, SRSF2, U2AF1, ASXL1, and RUNX1 mutations were more frequent in men. The median overall survival (mOS) was 37.5 months (mo) for females compared to 35 monthsfor males, (P = .002). The mOS was significantly prolonged for women in lower-risk MDS, but not in higher-risk MDS. Women were more likely to respond to immunosuppression with ATG/CSA than men (38% vs. 19%, P= 0.04).Conclusion Ongoing research is needed for understanding the impact of sex on phenotype, genotype, and outcomes in patients diagnosed with MDS.

Clinical characteristics and outcomes of EZH2-mutant myelodysplastic syndrome: A large single institution analysis of 1774 patients.

EZH2 mutations in myeloid neoplasms are loss of function type, and have been linked to poor overall survival (OS) in patients with myelodysplastic syndrome (MDS). However, the specific determinants of outcomes in EZH2-mutant (mut) MDS are not well characterized. In this single-center retrospective study, clinical and genomic data were collected on 1774 patients with MDS treated at Moffitt Cancer Center. In our cohort, 83 (4.7%) patients had a pathogenic EZH2 mutation. Patients with EZH2mut MDS were older than EZH2-wild type (wt) group (median age- 72 vs. 69 years, p = 0.010). The most common co-occurring mutation in EZH2mut MDS was ASXL1, with a significantly higher frequency than EZH2wt (54% vs. 19%, p < 0.001). Patients with EZH2mut MDS had lower response rates to hypomethylating agents compared to EZH2wt MDS (26% vs. 39%; p = 0.050). Median OS of patients with EZH2mut MDS was 30.8 months, with a significantly worse OS than EZH2wt group (35.5 vs. 61.2 months, p = 0.003) in the lower-risk IPSS-R categories. Among patients with EZH2mut MDS, co-presence of ASXL1 or RUNX1 mutations was associated with inferior median OS compared to their wt counterparts (26.8 vs. 48.7 months, p = 0.031). Concurrent chromosome 7 abnormalities (12%) were also associated with significantly worse OS (median OS- 20.8 vs. 35.5 months, p = 0.002) in EZH2mut MDS. Future clinical trials should explore the potential role of novel targeted therapies in improving outcomes in patients with EZH2mut MDS.

Interrogation of molecular profiles can help in differentiating between MDS and AML with MDS-related changes.

A subset of AML with myelodysplastic syndrome (MDS)-related changes (MRCs) occurs without a documented MDS phase. We studied genomic profile of 646 patients: 310 with MDS, 167 with AML without (w/o) MRC, 99 with primary (p) AML-MRC, and 70 with secondary (s) AML-MRC and sought to find differences in mutational patterns. Among the 32-myeloid associated genes studied, SF3B1 (p ≤ .001) was significantly mutated in higher proportion of patients with MDS, compared to other categories. NPM1 (p < .001), FLT3 ITD (p = .08), and NRAS (p = .02) mutations showed trend toward significance for AML w/o MRC, compared to other categories. In pAML-MRC, TP53 (p < .001) was significantly mutated in higher proportion of patients. Similarly, SETBP1 (p = .001), RUNX1 (p = .004), and SRSF2 (p = .04) mutations were more commonly seen in sAML-MRC. While these signatures may not be diagnostically discriminatory, they may help in disease categorization when other data are absent or in challenging cases.

Genetic Landscape of Acute Myeloid Leukemia Interrogated by Next-generation Sequencing: A Large Cancer Center Experience.

BACKGROUND/AIM: Acute myeloid leukemia (AML) represents a heterogeneous disease with varying morphologic, immunophenotypic, and genetic features, along with varying patient outcomes. The genomic tractability of AML makes it amenable for targeted next-generation sequencing (NGS) testing clinically. MATERIALS AND METHODS: One hundred eights-seven unique patients with a diagnosis of acute myeloid leukemia between May 2011 and Oct 2014 and with mutational analysis by NGS were included in this study. The distribution of gene mutations was investigated in different subcategories of AML. RESULTS: Most patients in this study (n=182) received Genoptix testing (either 5-gene panel or 21-gene panel). In 130/187 (70%) cases, there was an average of 2.3 mutations per case (range=0-7 mutations). We specifically mention mutations in 32 genes, their significance and co-occurrence as detected in different types of AML. CONCLUSION: The genetic heterogeneity of AML signifies the importance of taking a personalized-medicine approach to the management of patients with AML.