Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Jan 6:12:1092201.
doi: 10.3389/fonc.2022.1092201. eCollection 2022.

Molecular profiling of male breast cancer by multigene panel testing: Implications for precision oncology

Affiliations

Molecular profiling of male breast cancer by multigene panel testing: Implications for precision oncology

Virginia Valentini et al. Front Oncol. .

Abstract

Introduction: Compared with breast cancer (BC) in women, BC in men is a rare disease with genetic and molecular peculiarities. Therapeutic approaches for male BC (MBC) are currently extrapolated from the clinical management of female BC, although the disease does not exactly overlap in males and females. Data on specific molecular biomarkers in MBC are lacking, cutting out male patients from more appropriate therapeutic strategies. Growing evidence indicates that Next Generation Sequencing (NGS) multigene panel testing can be used for the detection of predictive molecular biomarkers, including Tumor Mutational Burden (TMB) and Microsatellite Instability (MSI).

Methods: In this study, NGS multigene gene panel sequencing, targeting 1.94 Mb of the genome at 523 cancer-relevant genes (TruSight Oncology 500, Illumina), was used to identify and characterize somatic variants, Copy Number Variations (CNVs), TMB and MSI, in 15 Formalin-Fixed Paraffin-Embedded (FFPE) male breast cancer samples.

Results and discussion: A total of 40 pathogenic variants were detected in 24 genes. All MBC cases harbored at least one pathogenic variant. PIK3CA was the most frequently mutated gene, with six (40.0%) MBCs harboring targetable PIK3CA alterations. CNVs analysis showed copy number gains in 22 genes. No copy number losses were found. Specifically, 13 (86.7%) MBCs showed gene copy number gains. MYC was the most frequently amplified gene with eight (53.3%) MBCs showing a median fold-changes value of 1.9 (range 1.8-3.8). A median TMB value of 4.3 (range 0.8-12.3) mut/Mb was observed, with two (13%) MBCs showing high-TMB. The median percentage of MSI was 2.4% (range 0-17.6%), with two (13%) MBCs showing high-MSI. Overall, these results indicate that NGS multigene panel sequencing can provide a comprehensive molecular tumor profiling in MBC. The identification of targetable molecular alterations in more than 70% of MBCs suggests that the NGS approach may allow for the selection of MBC patients eligible for precision/targeted therapy.

Keywords: clinically actionable genetic variants; copy number variations (CNVs); male breast cancer (MBC); microsatellite instability (MSI); precision oncology; targeted gene panel sequencing; tumor mutational burden (TMB); tumor profiling.

PubMed Disclaimer

Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

Figure 1
Figure 1
Number of somatic pathogenic variants identified in MBCs using TruSight Oncology 500. (A) Number of somatic pathogenic variants identified, by gene. (B) Number of somatic pathogenic variants identified, by sample.
Figure 2
Figure 2
Percentage of MBCs with DNA Copy Number Variations (CNVs), by altered gene.
Figure 3
Figure 3
TMB (mut/Mb) and MSI (%) of MBCs analyzed. (A) Distribution of TMB (y-axis), by sample. (B) Distribution of MSI (y-axis), by sample. NA, not available.
Figure 4
Figure 4
Somatic non-synonymous variants in 15 MBCs. Mutated genes are represented as rows, and individual patients are represented as columns. Clinical data, tumor histology and molecular biomarkers investigated are indicated by the horizontal bars.

Similar articles

Cited by

References

    1. Ottini L. Male Breast cancer: a rare disease that might uncover underlying pathways of breast cancer. Nat Rev Cancer (2014) 14(10):643. doi: 10.1038/nrc3806 - DOI - PubMed
    1. Chen Z, Xu L, Shi W, Zeng F, Zhuo R, Hao X, et al. . Trends of female and male breast cancer incidence at the global, regional, and national levels, 1990-2017. Breast Cancer Res Treat (2020) 180(2):481–90. doi: 10.1007/s10549-020-05561-1 - DOI - PubMed
    1. Zelli V, Silvestri V, Valentini V, Bucalo A, Rizzolo P, Zanna I, et al. . Transcriptome of Male breast cancer matched with germline profiling reveals novel molecular subtypes with possible clinical relevance. Cancers (2021) 13(18):4515. doi: 10.3390/cancers13184515 - DOI - PMC - PubMed
    1. Hassett MJ, Somerfield MR, Baker ER, Cardoso F, Kansal KJ, Kwait DC, et al. . Management of Male breast cancer: ASCO guideline. J Clin Oncol (2020) 38(16):1849–63. doi: 10.1200/JCO.19.03120 - DOI - PubMed
    1. Gnerlich JL, Deshpande AD, Jeffe DB, Seelam S, Kimbuende E, Margenthaler JA. Poorer survival outcomes for male breast cancer compared with female breast cancer may be attributable to in-stage migration. Ann Surg Oncol (2011) 18(7):1837–44. doi: 10.1245/s10434-010-1468-3 - DOI - PMC - PubMed