%0 Journal Article %A IOANNIS PANAGOPOULOS %A LUDMILA GORUNOVA %A KRISTIN ANDERSEN %A MARIUS LUND-IVERSEN %A HANNE REGINE HOGNESTAD %A INGVILD LOBMAIER %A FRANCESCA MICCI %A SVERRE HEIM %T Chromosomal Translocation t(5;12)(p13;q14) Leading to Fusion of High-mobility Group AT-hook 2 Gene With Intergenic Sequences From Chromosome Sub-Band 5p13.2 in Benign Myoid Neoplasms of the Breast: A Second Case %D 2022 %R 10.21873/cgp.20331 %J Cancer Genomics - Proteomics %P 445-455 %V 19 %N 4 %X Background/Aim: Recently, we reported a myoid hamartoma carrying a t(5;12)(p13;q14) karyotypic aberration leading to fusion of the high-mobility group AT-hook 2 (HMGA2) gene with a sequence from chromosome sub-band 5p13.2. We describe here another benign myoid tumor of the breast with identical genetic aberrations. Materials and Methods: A mammary leiomyomatous tumor found in a 45-year-old woman was studied using cytogenetics, fluorescence in situ hybridization, RNA sequencing, reverse transcription-polymerase chain reaction and Sanger sequencing. Results: The karyotype of the tumor cells was 46,XX,t(5;12) (p13;q14)[14]. Fluorescence in situ hybridization showed rearrangement of HMGA2, RNA sequencing detected fusion of HMGA2 with a sequence from 5p13.2, whereupon reverse transcription-polymerase chain reaction together with Sanger sequencing verified the HMGA2-fusion transcript. The results were identical to those obtained by us previously in a myoid hamartoma of the breast. Conclusion: The translocation t(5;12)(p13;q14) and fusion of HMGA2 with sequences from sub-band 5p13.2 appear to be recurrent events in benign mammary myoid neoplasms. %U https://cgp.iiarjournals.org/content/cgp/19/4/445.full.pdf