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Comparative Lesions Analysis Through a Targeted Sequencing Approach
Published on: November 5, 2019
CCND1 Copy Number Variation in Circulating Tumor DNA from Luminal B Breast Cancer Patients
Akiko Shimazaki1, Makoto Kubo2, Kanako Kurata3
1Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Background/Aim:
Abnormalities in the cyclin D1-CDK4/6 complex have been implicated in breast cancer proliferation and resistance to treatment. Recently, new drugs have been developed to target CDK4/6. Meanwhile, liquid biopsy has received great interest in oncology. In this study, we analyzed cyclin D1 gene (CCND1) copy number variation (CNV) in circulating tumor DNA (ctDNA) from luminal B breast cancer patients.
Patients And Methods:
This study included 31 patients with luminal B breast cancer who underwent resection. We analyzed CCND1 CNV in ctDNA by digital droplet PCR.
Results:
Of the 31 luminal B breast cancers, CCND1 CNV was positive in 5 cases. Patients with CCND1 CNV positivity had significantly shorter recurrence-free survival than patients with negative CCND1 CNV.
Conclusion:
CCND1 CNV in ctDNA was associated with poor prognosis in patients with luminal B breast cancer. This biomarker could be a useful prognostic factor.

