Gangat, Naseema

Abstract In this study, we aimed to characterize the molecular mechanisms of two very rare subtypes of AML: acute megakaryoblastic leukemia (AMKL) and acute panmyelosis with myelofibrosis (APMF). Our goal is to describe the clinical-pathologic features of APMF and explore the genomic landscape AMKL to further understand these rare malignancies. We identified 35 patients diagnosed with AMKL (n=27) and APMF (n=8) at Mayo Clinic between 1995 and 2015 by retrospective chart review. For 10 of the AMKL patients, tissue was available for whole-exome sequencing and was analyzed in comparison to a published AML reference population. The median overall survival was shorter in patients with AMKL (3.9 months, 95% CI 1.7-7.4) than in patients with APMF (14.3 months, 95% CI 0.7-NE, p = 0.026,). For both AMKL and APMF, patients who underwent allogeneic hematopoietic stem cell transplantation had better overall survival (14.3 months, 95% CI 1.9-NE) compared to those not undergoing transplantation (4.6 months, 95% CI 1.5-7.4, p = 0.003). Patients with AMKL presented more frequently with splenomegaly, with higher peripheral blood blast counts, and with higher serum lactate dehydrogenase concentrations. 9 out of 10 AMKL patients with available tissue for sequencing demonstrated variants in 22 of 35 AML driver genes, with JAK2 V617F as the most common mutation. Although our small study numbers preclude firm conclusions, it does reflect the rarity of these AML subtypes. Furthermore, inferior survival in AMKL (compared to APMF) was reflected in its proliferative disease features such as splenomegaly, high blast counts, and high lactate dehydrogenase. Interestingly, the presence of JAK2 V617F variants in 40% of the interrogated samples was higher than expected. Although JAK2 is a known molecular driver in myeloproliferative neoplasms, it is actually very rare in de novo AML (~1%). Despite improved survival with allogeneic stem cell transplant, we can conclude that treatment outcomes for AMKL and APMF with standard-of-care therapy were sobering and that patients with these rare AML subtypes should undergo molecular evaluation to qualify them for clinical trials with novel targeted therapies. Citation Format: Marissa Li, Moritz Binder, Basma Basha, Ben Zhang, Alejandro Ferrer, Yuanhan Liu, Mrinal Patnaik, David Viswanatha, Naseema Gangat. Acute megakaryoblastic leukemia is associated with poor overall survival and enriched in JAK2 variants [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr B03.

e19538 Background: Chronic neutrophilic leukemia (CNL) is a rare and aggressive myeloproliferative neoplasm with poor survival. No standard of care exists. Case reports describe allogeneic stem cell transplantation (ASCT) as the only curative therapy. Using the National Cancer Database (NCDB), we studied prognostic factors and survival outcomes of CNL. Methods: Patients diagnosed in 2004-2015 were included. 9963/3 was the ICD-O-3 code. Overall survival (OS) was analyzed using the Kaplan-Meier method. Hazard ratios (HR) with confidence intervals (CI) were calculated using Cox proportional hazards model. Variables significant in univariate analysis were included in a multivariate analysis. Data on incidence was obtained from the Surveillance, Epidemiology, and End Results Program (SEER) 21 Registries (2004-2015). The analysis was done with SEER*Stat software. Incidence was age-adjusted to the U.S. 2000 standard population. Results: A total of 121 CNL patients were in NCDB. The median age at diagnosis was 70 years (range 21-90); 74 (61%) were males and 107 (88%) were ≥ 50 years. The median follow up time was 5.8 years (interquartile range [IQR] 2.9-7.4). 32 (26%) had a Charlson Deyo score (CDS) > 1. 80 (70%) had government insurance, while 34 (30%) had private insurance. Median OS was 2.2 years (IQR 0.8-6.7). OS was 70% at 1 year, 29% at 5 years, and 11% at 10 years. The year of diagnosis was not associated with improved OS (HR: 0.95 (95% CI: 0.88-1.02), p =0.14). 71 (59%) patients received chemotherapy. The median time to chemotherapy from the day of diagnosis was 15 days (IQR 7-35). The OS of those who received chemotherapy was 71% at 1 year and 27% at 5 years versus 69% and 32% at 1- and 5- years for those who did not ( p= 0.38). 2 patients received ASCT (age 52 and 61 years) as initial therapy and both were alive at 5 years. Factors predicting inferior OS on univariate analysis were age ≥ 50 years at diagnosis ( p= 0.005), male ( p< 0.001), CDS > 1 ( p= 0.038), and government insurance ( p= 0.004). The table shows the multivariate (MV) analysis. The overall incidence of CNL was 0.1 cases/1,000,000 individuals and did not change significantly from 2004-2015. The incidences by male, female, White, Black, and American Indian/Alaska Native were also 0.1 cases/1,000,000 individuals. Conclusions: OS and incidence of CNL have not changed over the years. Age ≥ 50 years, male gender, and use of government insurance predicted inferior OS. [Table: see text]

Abstract Background Estrogen-based hormone treatment (EBHT), in the form of either oral contraceptives or hormone replacement therapy, is generally felt to be associated with an increased risk of thrombosis in women with essential thrombocythemia (ET). However, there is insufficient evidence to support or refute such a concern. Methods Data was abstracted from medical records of a consecutive cohort of women with ET seen at the Mayo Clinic. Thrombotic risk was determined by the occurrence of a major thrombotic event namely myocardial infarction, angina, cerebrovascular accident, transient ischemic attack, peripheral arterial thrombosis, pulmonary embolism, or deep venous thrombosis at or after diagnosis of ET. Results i. Information regarding EBHT at or after the diagnosis of ET The study cohort included 307 women with ET (median age, 55 years; range 16–88) with a median follow-up of 133 months from diagnosis (range, 0.2–397). EBHT at or after diagnosis was documented in 93 women (30%); 59 patients were on EBHT at time of diagnosis and treatment was initiated after diagnosis in 34 patients. Among the 59 patients who were receiving EBHT at the time of diagnosis, treatment was discontinued within one month of their ET diagnosis in 17 patients but continued in the other 42 patients for a median of 48 months (range, 2–168). In the 34 patients with EBHT that was initiated after the diagnosis of ET, median treatment period was 44 months (range, 1–144). ii. Correlation between EBHT and thrombosis at diagnosis At diagnosis, major thrombosis was documented in a total of 74 patients (24%) that included 11 of the 59 patients (19%) on EBHT and 63 of 248 patients (25%) that were not receiving such therapy at the time of diagnosis (p=0.28). iii. Correlation between EBHT and thrombosis after diagnosis A total of 95 patients (31%) experienced a subsequent (i.e. post-diagnosis) thrombotic episode during the study period. These occurred in 65 of 214 patients (30%) that were not exposed to EBHT at or after diagnosis, 5 of 17 patients (29%) in whom EBHT was discontinued with the diagnosis of ET, 13 of 42 patients (31%) in whom EBHT was continued despite the diagnosis of ET, and 12 of 34 patients (35%) in whom EBHT was started after the diagnosis of ET (p=0.95). Furthermore, duration of EBHT, using a cutoff value of 1 year, did not significantly affect the incidence of thrombotic events (p=0.67). The different comparative groups were similar in age distribution as well as frequency of other cardiovascular risk factors including smoking, diabetes mellitus, hypertension, and hyperlipidemia. Conclusion The current study addresses the important issue of safety pertaining to the use of estrogen-based hormones in women with ET and did not reveal a significant alteration of thrombosis risk as a result of hormone therapy.

Abstract Background: Leukocytosis has recently been implicated as an adverse prognostic feature for thrombosis in both ET and PV. Such an association would be therapeutically most relevant in the context of “low-risk” disease. In the current study, we sought to clarify the relationship between leukocytosis at diagnosis and the subsequent occurrence of either arterial or venous thrombosis, in “low-risk” patients with ET or PV. Methods: Data was abstracted from the medical records of a consecutive cohort of patients with WHO-defined ET or PV seen at the Mayo Clinic. Low-risk disease was defined by the absence of both thrombosis history and age 3 60 years. Cox proportional hazards model was utilized to determine the impact of clinical and laboratory variables on thrombosis-free survival (TFS). Arterial- or venous-specific TFS curves were constructed by Kaplan-Meier method. Results: i) Patient characteristics and outcome A total of 407 “low-risk” patients were studied; 153 had PV (median age 48 years; females 43%) and 254 ET (median age 42 years; females 71%). A total of 46 thrombotic events (22 arterial and 24 venous) were recorded in 41 (27%) patients with PV during a median follow up of 130 months (range 2–562 months). The corresponding figures in ET were 54 total thrombotic events (41 arterial and 14 venous) in 47 (19%) patients at a median follow up of 104 months (range 0.25–424 months). Cytoreductive therapy was avoided in the presence of &lt; 1000 x 109/L platelet count but, at the discretion of the treating physician, some patients with higher platelet counts received prophylactic cytoreductive therapy. ii) Correlation between leukocytosis and thrombosis A leukocyte count of 3 15 x 109/L at diagnosis was documented in 42 (27%) patients with PV and 21 (8%) patients with ET; 102 patients (40%) with ET had &gt; 9.4 x 109/L leukocyte count. Leukocyte count considered as either a continuous or categorical variable (using cutoff levels of 15 x 109/L for PV and either 15 x 109/L or 9.4 x 109/L for ET) was not significantly associated with either arterial or venous thrombosis (Figure 1). iii) Correlation between other risk factors and thrombosis In univariate analysis, presence of the JAK2V617F was significantly associated with arterial thrombosis in ET (p=0.049) but significance was lost during multivariable analysis that included age as a covariate. Only advanced age was found to be significantly associated with arterial thrombosis in PV (p=0.04) and higher hemoglobin level with venous thrombosis in ET (p&lt;0.0001). Conclusion: The current study does not identify leukocyte count at diagnosis as a marker of increased thrombosis risk in low-risk patients with either ET or PV. Instead, the study found an association between arterial thrombosis and advanced age in PV and venous thrombosis and higher hemoglobin level in ET. Figure Figure

Abstract Background: While currently-diagnosable hematological cancer is a potent VTE risk factor (RR range =12–32), whether undiagnosable hematological cancer is a risk factor is uncertain. Objective: To estimate the hazard of subsequent hematological cancer among incident VTE patients with no apparent active hematological cancer within ± 3 months of the VTE event. Methods: In a population-based cohort study, we followed Olmsted County, MN residents with incident VTE over the 27-year period, 1973–1999, and previously matched Olmsted County residents without VTE, who survived with no apparent active hematological cancer within ± 3 months of the VTE event or a routine medical visit date, respectively, forward in time through their complete medical records in the community for hematological cancer. Data were abstracted on baseline demographic and clinical characteristics, type and stage of hematological cancer, and any prior solid tumor treatments. For cases and controls, hematological cancer-free survival from the event date was estimated by the Kaplan Meier method, and the homogeneity of survival curves was examined by the log-rank test. Cox proportional hazards regression was used to adjust for covariates. Results: 1860 VTE cases (56% females) and 1890 controls (53% females) were followed for 16,497 and 15,320 person-years, respectively, conditional on surviving 3-months free of hematological cancer. 43 VTE cases and 24 controls developed hematological cancer at a median of 63.5 months (range 0.7 – 334 months). The median age for cases was 63.2 years compared to 67.8 years for the controls (p&lt;0.001). Hematological cancer types included non-Hodgkin’s lymphoma (n=19), chronic lymphocytic leukemia (n=11), acute myeloid leukemia (n=1), multiple myeloma (n=9), myeloproliferative disorders (n=10), and myelodysplastic syndromes (n=14). Case status was not univariately associated with subsequent hematologic cancer (HR=1.42; 95% CI: 0.85, 2.39; p=0.18). After adjusting for age, also associated with cancer, case status was significantly associated with hematological cancer (HR=1.90; 95% CI: 1.13, 3.20; p=0.015). Conclusions: Incident VTE patients have nearly a two-fold increased risk of subsequent hematological cancer. We hypothesize that VTE can be the initial manifestation of an occult hematological cancer clone.

Abstract Background: Essential thrombocythemia (ET) frequently occurs in women of childbearing age. Recently, an increased risk of pregnancy complications was reported in patients with ET carrying the JAK2V617F mutation (Passamonti et al. Blood. 2007;110:485). In the current study, we sought to validate this observation as well as identify other predictors of pregnancy loss in ET. Methods: Data was abstracted from the medical records of a consecutive cohort of patients with WHO-defined ET seen at the Mayo Clinic. Patient characteristics and pregnancy outcome are summarized using descriptive statistics. The analysis of risk factors associated with pregnancy complications was carried out by both univariate and multivariate analyses. Results: i) Patient characteristics at ET diagnosis A total of 63 pregnancies were recorded in 36 women at or after their diagnosis of ET. At diagnosis of ET, median (range) values were: age 26 years (15–36), platelet count 1350 x 109/L (683–3300), hemoglobin level 13.3 g/dL (10.5–16) and leukocyte count 9.3 x109/L (5–26.9). JAK2V617F mutation analysis was performed in 20 patients; half were positive. Only 5 patients had a history of thrombosis at diagnosis. Follow-up after ET diagnosis was for a median of 82.9 months (range, 6.5–340.8 months). ii) Outcome of first pregnancy at or after diagnosis of ET A total of 36 first pregnancies were documented at or after the diagnosis of ET. At the time, median (range) values were: time from diagnosis 25.5 months (0–155), age 28 years (20–36), platelet count 840 x 109/L (255–1998), hemoglobin 12.9 g/dl (9–16.6) and leukocyte count 8.4 x109/L (6.6–19.8). Seven of the 36 (19%) women were receiving cytoreductive therapy at time of conception: anagrelide (n=4), interferon (n=1), hydroxyurea (n=1) and radiophosphorus (n=1). Aspirin therapy was documented in 53% of the women at time of conception and in 69% during the first trimester of their pregnancy. Among the 36 first pregnancies, 61% (n=22) resulted in live birth and 39% (n=14) in fetal loss. Twelve of the 14 pregnancy losses occurred during the first trimester (10 spontaneous miscarriages, 1 ectopic pregnancy and 1 therapeutic abortion) and the remaining two during the second trimester. Maternal complications occurred in 11% (n=4) of pregnancies and included pre-eclampsia (n=1), hematoma after Cesarean-section (n=2) and post-partum hemorrhage (n=1). iii) Predictors of first pregnancy outcome in ET Pregnancy outcome, in terms of live birth versus miscarriage did not correlate with age (p=0.27), presence of cardiovascular risk factor (p=0.76), platelet count (p=0.49), leukocyte count (p=0.67) or hemoglobin level (p=0.31). Similarly, pregnancy loss was similar between JAK2V617F-positive (4 of 10 pregnancies) and JAK2V617F-negative (4 of 10 pregnancies) patients (p&gt;0.9). Furthermore, among 5 cases of 3 consecutive miscarriages, 4 were JAK2V617F-negative. Interestingly, the rate of pregnancy loss was only 21% among 24 patients receiving aspirin therapy during the first trimester as compared to 75% among the 12 patients in whom no such treatment was documented (p=0.002). iv) Second and subsequent pregnancy outcome Seventeen second pregnancies were recorded; 71% (n=12) resulted in live birth that included 8 of 9 patients with successful and 4 of 8 with unsuccessful first pregnancies (p=0.07). The trend was similar among 7 third pregnancies, which resulted in only one live birth; 5 of the 6 fetal losses occurred in women with history of first pregnancy loss (p=0.09). Conclusion: The current study does not support the recently communicated association between the presence of JAK2V617F and increased risk of pregnancy loss in ET. Instead, two parameters of potential importance for predicting pregnancy outcome in ET were identified; the occurrence of a miscarriage might be a marker for a similar event during subsequent pregnancies whereas aspirin therapy during the first trimester might be beneficial.