The clinical implications of BCOR mutations in a large cohort of acute myeloid leukemia patients: a 5-year single-center retrospective study.

To elucidate the effect of BCOR mutation (BCORmut) on clinical outcomes, we included a total of 899 consecutive AML patients in a single-center during July 2016 to December 2021. Fifty cases (5.6%) had BCOR mutations, which co-occurred with mutations of RUNX1, DNMT3A, IDH2, BCORL1, STAG2, SF3B1 and U2AF1, but were exclusive with KIT and CEBPA mutations. BCORmut was also found to be exclusive with t(8;21)(q22;q22.1) AML in all patients and MLL rearrangements in the European Leukemia Net (ELN) adverse group. In those receiving intensive chemotherapy regimens, BCORmut was associated with lower complete remission (CR) rates and worse prognosis. Subgroup analysis showed that BCORmut mainly conferred a poor prognosis in the intermediate and adverse groups of the ELN2017 risk. These results suggest that BCOR mutation is an independent prognostic parameter in AML, implying BCOR mutation as a novel marker for chemorefractory disease and inferior prognosis.

Recurrent Somatic Chromosomal Abnormalities in Relapsed Extraocular Retinoblastoma.

Most reports about copy number alterations (CNA) in retinoblastoma relate to patients with intraocular disease and features of children with extraocular relapse remain unknown, so we aimed to describe the CNA in this population. We evaluated 23 patients and 27 specimens from 4 centers. Seventeen cases had extraocular relapse after initial enucleation and six cases after an initial preservation attempt. We performed an analysis of CNA and BCOR gene alteration by SNP array (Single Nucleotide Polymorfism array), whole-exome sequencing, IMPACT panel and CGH array (Array-based comparative genomic hybridization). All cases presented CNA at a higher prevalence than those reported in previously published studies for intraocular cases. CNA previously reported for intraocular retinoblastoma were found at a high frequency in our cohort: gains in 1q (69.5%), 2p (60.9%) and 6p (86.9%), and 16q loss (78.2%). Other, previously less-recognized, CNA were found including loss of 11q (34.8%), gain of 17q (56.5%), loss of 19q (30.4%) and BCOR alterations were present in 72.7% of our cases. A high number of CNA including 11q deletions, 17q gains, 19q loss, and BCOR alterations, are more common in extraocular retinoblastoma. Identification of these features may be correlated with a more aggressive tumor warranting consideration for patient management.