Background: Uterine leiomyosarcomas are rare tumors with adverse prognosis. Recently, it has been suggested that a possible genetic subgroup of these tumors might be characterized by bi-allelic deletions of the RB1 locus. Here we report another uterine leiomyosarcoma with bi-allelic deletion of RB1 along with other genetic alterations.
Case report: A 52-year-old patient was admitted to the hospital for surgical removal of a polyp-like lesion in the uterine cavity. Histological examination revealed a grade 1 leiomyosarcoma with atypical mitoses and areas corresponding to a leiomyoma with bizarre nuclei.
Results and conclusion: This is the third case of a uterine leiomyosarcoma revealing bi-allelic RB1 deletions. Thus, in the absence of monosomy 14 and/or mutations of MED12, this genetic alteration seems, indeed, to constitute a separate entity of these tumors. Histological analysis of the tumor along with its genetic intratumoral heterogeneity suggests its origin to be from a leiomyoma with bizarre nuclei. Furthermore, of considerable interest in the case presented here, is the identification of a large segment of chromosome 22 showing uniparental disomy. Along with the case presented here, recent data show that a genetic classification of all uterine leiomyosarcomas is recommended to reveal more information about clinical correlations of their different genetic subtypes. Due to array-based methods these analyses can be well-carried out using paraffin-embedded samples.
Keywords: LOH; RB1; UPD; Uterine leiomyosarcoma; deletion; genetic alterations; loss of heterozygosity; uniparental disomy.
Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.