CASE REPORT t(15; 17) associated with primary myelofibrosis: a case report of an unusual clinical presentation and diagnostic dilemma This article was published in the following Dove Press journal: OncoTargets and Therapy Kalyan Nadiminti 1 Margarida Silverman 1 Sharathkumar Bhagavathi 2 Praveen Vikas 1 1 Division of Hematology and Blood and Marrow Transplantation, University of Iowa Hospital and Clinics, Iowa City, IA, USA; 2 Department of Pathology, University of Iowa Hospitals and Clinics, Iowa City, IA, USA Background: primary myelofibrosis (PMF) is a myeloproliferative neoplasm which is associated with clonal molecular and cytogenetic abnormalities (CA) and varied clinical manifestations. While various CA have been previously described, t(15; 17) has not been reported in association with this condition. Case presentation: A 69-year-old male presented with constitutional symptoms, cytopenias and bone marrow biopsy revealed immature blasts with fibrosis. Cytogenetic analysis showed a t(15;17) which initially suggested a diagnosis of acute promyelocytic leukemia (APL). However, flourescence in situ hybridization (FISH) and reverse transcriptase polymerase chain reaction (RT-PCR) studies were negative for transcripts promyelocytic leukemia (PML) gene and retinoic acid receptor alpha (RARA) or PML-RARA fusion. Along with these results, a second review of bone marrow histology, flowcytometry and the detection of a calreticulin gene (CALR) mutation helped with the correct diagnosis of PMF. Patient was then treated with ruxolitinib, a JAK (Janus kinase) 1 and 2 inhibitor, and eventually proceeded to receive a matched unrelated reduced intensity conditioning (RIC) allogeneic stem cell transplantation (ASCT) and has been doing well at the 6-month follow up. Conclusions: Our case highlights two points, that the t(15;17) is diagnostic of Acute Promyelocytic Leukemia (APL) in most cases, there are exceptions and it can be associated with other malignancies without causing any APL like features, as noted in this case. Also, that t(15; 17) by itself is never sufficient to diagnose APL without confirmation by other methods and relying solely on cytogenetics without timely confirmatory tests can lead to risks of delay in diagnosis and appropriate management. Keywords: primary myelofibrosis, atypical t(15;17), cytogenetics, FISH, case report Introduction Myelofibrosis (MF) is a clonal myeloproliferative neoplasm which can manifest with a constellation of findings such as anemia, constitutional symptoms, hepatosplenome- galy or thrombosis. It can present as primary myelofibrosis (PMF) or as secondary MF progressing from polycythemia vera or essential thrombocythemia (post-PV/post ET MF). 1,2 According to the revised WHO 2016 update on myeloid neoplasms, presence of JAK2, CALR and MPL mutations, or, in their absence, other frequently seen mutations such as ASXL1, EZH2, TET2, IDH1/IDH2, SRSF2, SF3B1 are one of the essential major criteria to establish clonality. 1 Cytogenetic abnormalities (CA) are observed only in about 40–45% of the cases and although not considered essential for diagnosis, they carry prognostic significance. 3 While no disease-characteristic Correspondence: Kalyan Nadiminti; Praveen Vikas Division of Hematology and Blood and Marrow Transplantation, University of Iowa Hospital and Clinics, 200 Hawkins Dr, Iowa City 52242, IA, USA Email Nadiminti.kalyanvaraganesh@mayo. edu; Praveen-vikas@uiowa.edu OncoTargets and Therapy Dovepress open access to scientific and medical research Open Access Full Text Article submit your manuscript | www.dovepress.com OncoTargets and Therapy 2019:12 5449–5455 5449 DovePress © 2019 Nadiminti et al. This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/ terms.php and incorporate the Creative Commons Attribution – Non Commercial (unported, v3.0) License (http://creativecommons.org/licenses/by-nc/3.0/). By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms (https://www.dovepress.com/terms.php). http://doi.org/10.2147/OTT.S208290 OncoTargets and Therapy downloaded from https://www.dovepress.com/ by 54.163.42.124 on 26-May-2020 For personal use only. 1 / 1