“Ideal” parathyroid hormone in erythropoietin‐stimulating agents‐resistant anemia

Abstract Erythropoietin‐stimulating agents (ESAs) have revolutionized anemia treatment in end‐stage renal disease (ESRD), but ESA resistance is increasingly identified. Secondary hyperparathyroidism (SHP) is one cause of ESA resistance. We describe a patient with ESA‐resistant, transfusion‐dependent anemia and mild SHP with remodeling and reticulin fibrosis on bone marrow biopsy, all of which resolved with stricter SHP management. We identified 64 patients with anemia, ESRD, and bone marrow biopsy. The parathyroid hormone (PTH) range for bony remodeling was 183–16,161.9 pg/ml versus 90.8–3283 pg/ml. The PTH range for fibrotic changes was 183–2487 pg/ml versus 90.8–16,161.9 pg/ml. We found no clear PTH range predictive for bone marrow changes

Hepatitis C Infection Associated with Acquired Pure Red Cell Aplasia

Acquired pure red cell aplasia is a rare bone marrow failure disorder characterized by many underlying etiologies. The hallmark bone marrow feature is the near absence of erythroid precursors that otherwise exhibit normal cellularity, which has been attributed to both immune- and cellular-mediated mechanisms. Besides being merely speculative and considering the rarity of the disorder, the description of acquired pure red cell aplasia clinical associations represents a unique occasion to improve our current clinical knowledge of the disease, reveal clues on its pathogenesis, and guide therapeutic decisions. The varied clinical scenarios and common acquired pure red cell aplasia associated conditions (i.e., thymoma, T cell/NK-cell large granular lymphocyte leukemia, B cell dyscrasia) suggest a heterogeneity of pathogenic routes. Viral etiologies must always be considered and worked up in the initial assessment of newly diagnosed acquired pure red cell aplasia patients. In this report, we present two cases of hepatitis-C-related acquired pure red cell aplasia and successful use of anti-viral strategies in the achievement of a complete response

Parafoveal acute middle maculopathy (PAMM) in sickle cell disease after discontinuation of hydroxyurea

Purpose: Paracentral acute middle maculopathy (PAMM) is a rare ophthalmologic emergency involving the intermediate and deep retinal capillary plexus that supply the retina's middle layers. This case report describes an episode of PAMM in a patient with sickle cell disease (SCD) to demonstrate the importance of early diagnosis, review potential pathophysiologic mechanisms, and finally discuss appropriate management in this patient population. Observations: A 33-year-old black female with SCD, who had recently discontinued disease-modifying therapy with hydroxyurea, presented with a central scotoma of the left eye. Examination showed superficial opacification and whitening of the temporal perifoveal macula. After an initial diagnosis of central retinal artery occlusion she was admitted for a stroke workup. MRI was negative for stroke, and the patient was discharged after undergoing a red blood cell exchange (RBCX). Follow-up exam and optical coherence tomography (OCT) findings were more consistent with PAMM. Conclusions and Importance: To our knowledge, this is the first report of PAMM after discontinuation of hydroxyurea in preparation for pregnancy. It highlights the importance of a multidisciplinary approach when treating peripartum patients with SCD and the need for further research regarding vaso-occlusive prophylactic agents and their effects in pregnancy to minimize morbidity during family planning

Distinct Clinical and Biological Implications of Various DNTMT3A Mutations in Myeloid Neoplasms

Abstract DNMT3A, a member of the DNA methyltransferases family along with DNMT1 and DNMT3B, is located on chromosome 2p23. Recurrent somatic mutations in DNMT3A are typically heterozygous and found mostly in non-CBF AML, less frequently in MDS and MPN. DNMT3A mutations are reported with other common myeloid mutations including NPM1, FLT3 and IDH1/2. The most canonical DNMT3A mutations are missense alteration in the R882 codon, accounting for >60% of all DNMT3A mutations and they imply dominant negative consequences. Overall, DNMT3A mutations carry a poor prognosis compared to the AML or MDS with wild type (WT) DNMT3A, although data within different subgroups (e.g., incorporating cytogenetic profiles) are conflicting. We hypothesized that molecular consequence of R882 mutations will differ from those of other somatic alterations of DNMT3A and may also result in distinct clinical features and outcomes. To test this theory, we analyzed a cohort of 1174 patients with myeloid neoplasias including 32% AML, 33% MDS, 13% MDS/MPN, 6% MPN and 16% other bone marrow failure disorders. These cases were subjected to multiamplicon targeted deep NGS including all ORFs of DNMT3A and other recurrently mutated genes. After application of various bioanalytic algorithms, confirmatory sequencing and thus stringent exclusion of all artifacts and germline alterations, we identified 140 somatic mutant cases (12% of the cohort), including 89 missense mutations (53 at R882, 19 at R693 and 17 other non-canonical missense alterations) and 51 truncations/frame shifts (all heterozygous). There was an age-related increase in the incidence of DNMT3A mutations, with the peak occurrence at 35-40 yrs. of age. Mutations in DNMT3A were most common in AML (54% in primary (p) AML, 8% in secondary (s) AML) followed by MDS (28%), MDS/MPN (4%), MPN (3%) and other bone marrow failure disorders (3%). Mutation in the R693 codon and truncating mutations were most commonly associated with MDS (p=.013) and sAML (p=.0013) whereas mutation occurring in codon R882 and other non-canonical missense mutations were frequently associated with pAML (p=.00001). For the whole cohort, DNMT3A mutations were most frequently associated with NPM1 (21% vs 8%, p=.014), FLT3 (24% vs. 2%, p=.0001), and IDH1/2 (26% vs. 8%, p=.001), compared to wild type DNMT3A. However, PRC2 complex mutations were less likely to occur in the context of DNMT3A mutations (6% vs. 24%, p=.0006). Canonical R882 mutation was commonly associated with FLT3 (p=.03) mutations, while truncating mutations were not (p=.03). Analyses of clonal hierarchy by ranking of VAF values demonstrated that 53% of DNMT3A mutations were dominant (mean VAF 39%, range 5-93%) (n=74/140). When DNMT3A mutations were dominant, IDH 1/2 (14%), TET2 (9%), ASXL (5%), PRC2 complex (3%) and BCOR (3%) mutations were common secondary events. In subgroup analyses, 55% of mutations in the R693 codon were dominant compared to 45% in R882 and 47% in truncating mutations. TET2 mutations were the most common associated secondary hits in dominant R693 mutations (n=10) compared to truncating (n=24) and R882 mutations (n=23) (40% vs. 8% vs. none, p=.0001). When DNMT3A mutations are secondary (mean VAF 34%, range 1-60%), as in 47% of our cases (n=66/140), then the common first hits were TET2 (10%), U2AF1 (8%) and cohesin complex (RAD21, SMC3, STAG2) mutations (6%). Dominant DNMT3A mutations correlated with MDS/MPN (60%, p=.007), while secondary DNMT3A mutations correlated with sAML (73%, p=.001). DNMT3A mutant myeloid neoplasms showed worse survival (p<.0001) compared to WT cases. Among different subgroups, there was significant difference in OS between R882, R693, truncating and other non-canonical missense mutations (p=.013). The R882 mutations had worse survival compared to other DNMT3A mutations (p=.003). Non-canonical mutations (truncating and other missense) vs. canonical mutations (R882 and R693) had better survival (p<.04). Survival for mutant R882 DNMT3A was worse compared to truncating mutations (p=.005) while there was no difference between R693 and truncating mutations. Among AML cases, R882 mutations vs. other mutations had worse survival (p=.01) while in MDS and MDS/MPN there was no significant difference in OS. DNTMT3A mutations often occur as founder lesion in AML. Our study shows that different types of mutations other than canonical R882 alterations may have a differential impact on OS and distinct clinical features. Disclosures Carraway: Celgene Corporation: Research Funding, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees; Baxalta: Speakers Bureau; Amgen: Membership on an entity's Board of Directors or advisory committees; Incyte: Membership on an entity's Board of Directors or advisory committees

Clonal Dynamics of Refractory Aplastic Anemia in Patients Treated with Eltrombopag

Abstract Despite documented success of immunosuppressive therapy (IST) in the treatment of AA, a minority of patients remain refractory, most responses are incomplete, and use of hematopoietic cell transplantation (HCT) is limited in older patients or those with significant comorbidities. While the introduction of the cMpl agonist eltrombopag (EPG) as salvage therapy or in conjunction with IST has revolutionized treatment for refractory AA. It may be effective in improving primary response rates to IST, engaging growth factor receptors with agonistic therapeutics (such as EPG) and also has the potential to promote evolution/expansion of mutant clones, thereby increasing the rate of progression to secondary myelodysplastic syndromes (MDS), a serious complication of AA occurring in 10-20% of patients. Clonogenic somatic mutations typical of MDS in patients with AA and PNH may increase the risk of progression to MDS. DNA from marrow samples of primary refractory AA patients was subjected to analysis before and after initiation of EPG to evaluate clonal expansion or evolution using a targeted multi-amplicon deep NGS panel of all ORFs of the top 60 most commonly mutated genes in MDS. In addition to the EPG treatment group, a case control cohort matched for age and duration from AA diagnosis to last clinical follow up (who did not receive EPG), was studied. Among 210 AA patients treated at Cleveland Clinic, we identified 26 who were treated with EPG for IST-refractory AA; median duration of treatment was 56 wks. The overall response rate after 12 weeks of therapy was 58% (15/26), while 31% of patients (8/26) showed stable disease with intermittent transfusions (one of whom underwent HCT). In 3 non-responders, one developed PNH, one had refractory AA/PNH, and one progressed to AML (see below). Expansion of PNH granulocytes after EPG treatment was observed in 23% of patients (6/26). In addition, 15% (4/26) had atypical subclonal chromosomal abnormalities. Prior to EPG, at least a single somatic event was found in 31% of patients (8/26), with 2 patients harboring 2 mutations. Events included CEBPA, EZH2, BCOR/BCORL1, ASXL1, U2AF1/2, TET2, and DNMT3A mutations. Following EPG therapy, acquisition of new somatic mutations was observed in 23% of cases, including RUNX1, U2AF1, BCOR, RIT1, and CEBPA. In cases with pre-existing clones, 6 clones expanded (e.g., BCOR or ASXL1 from VAF of 8 to 21% and 9 to 29%, respectively) despite clinical hematologic response, while in 2 cases clones disappeared (e.g., U2AF2 and BCORL1). In 54% of cases (14/26), we found detectable levels of a PNH clone at the time of diagnosis. Six of those cases had PNH clonal expansion post-EPG treatment, of which two developed clinically significant PNH clonal burden requiring eculizumab therapy. In the case-control cohort, 26 AA patients who received IST but were not treated with EPG, were followed for comparable time periods, and no evidence of progression to MDS was recorded. One patient was noted to have trisomy 15 on cytogenetics at diagnosis. "MDS type" molecular mutations were present in 10 patients similar to EPG cohort. Among these patients, 3 had persistent clones of U2AF1, DNMT3A, and STAT3 over one year without acquisition of any new molecular mutations. . PNH granulocytes expanded in 50% of AA cases, decreased in 30% and stayed stable in 20%. Thus, we did not observe any difference in expansion of PNH clones between those treated and untreated with EPG (p=0.73). Unlike for PNH clones, accounting for both new evolution and expansion of preexisting molecular mutations, the frequency of these clonal events was significantly higher in the EPG treated group (p=0.009). In conclusion, we observed occasional expansion of clones with potentially leukemogenic mutations during treatment with EPG in pts with AA. While higher rates of MDS evolution were not observed in this cohort of EPG treated patients, we found that serial evaluation of somatic mutations can inform clonal evolution and can potentially be used as abiomarker for evaluation of risk for post-AA MDS. Continued use of EPG in such patients should be judicious. Disclosures Carraway: Celgene: Research Funding, Speakers Bureau; Baxalta: Speakers Bureau; Incyte: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Sekeres:Millenium/Takeda: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees