2024-03-28T23:57:55Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/856222022-11-17T02:08:08Zhdl_2115_20040hdl_2115_121Aleukemic Extramedullary Blast Crisis as an Initial Presentation of Chronic Myeloid Leukemia with E1A3 BCR-ABL1 Fusion TranscriptMiyashita, NaokiOnozawa, MasahiroSuto, KeitoFujisawa, ShinichiOkazaki, NanaseHidaka, DaisukeOhigashi, HiroyukiYasumoto, AtsushiSugita, JunichiHashimoto, DaigoMatsuno, YoshihiroTeshima, Takanorie1a3extramedullary blast crisisPhiladelphia (Ph) chromosomeBCR-ABL1490Right neck swelling and pain occurred in a 49-year-old man. A Blood count showed a slight increase in platelet count without leukemoid reaction. After a biopsy of the cervical mass and bone marrow aspiration, a diagnosis of extramedullary blast crisis (EBC) of chronic myeloid leukemia (CML) was made. Fluorescence in situ hybridization (FISH) analysis showed a BCR-ABL1 fusion signal, but results of real-time polymerase chain reaction (RT-PCR) for major and minor BCR-ABL1 transcripts were negative. We identified a rare e1a 3 BCR-ABL1 fusion transcript. Administration of dasatinib resulted in disappearance of the extramedullary tumor. This is the first reported case of CML-EBC with e1a3 transcript. An aleukemic extramedullary tumor can be the initial presentation of CML.日本内科学会(The Japanese Society of Internal Medicine)Journal Articlehttp://hdl.handle.net/2115/856220918-2918Internal medicine617104910542022-04-01enginfo:doi/10.2169/internalmedicine.8319-21none