Abstract 4066
Background
Breast cancer (BC) represents the most common malignancy and has the highest mortality among women, both in the world and in Kazakhstan. Approximately 20-30% of cases of hereditary breast cancer are caused by presence of BRCA1 and BRCA2 genes defects. Also, there are additional genes which can increase the risk of BC and they are still under study.The aim of this study was to identify new, detectable and objective markers of key cancer genes by next-generation sequencing (NGS) in BC patients.
Methods
The study included 194 unrelated patients (the av/age 34.25 ± 4.56) with BC. Genomic DNA was obtained from peripheral blood,next-generation sequencing was performed using TruSightCancer Kit on the MiSeq platform,studio Variant was used to annotate genetic variants.
Results
In total, 61 pathogenic variants (all in heterozygous state) were found in 56 (28.9%) patients,the vast majority of variants located in BRCA1 (n = 19/56; 33.9%), 15 in BRCA2 (26.8%). The frequency of pathogenic variants in genes TP53 (8.9%), PALB2 (5.4%), MSH6 (5.4%), CHEK2 (3.6%), SDHB (3.6%), and WRN (3.6%) were higher than those genes APC, ATM, FANCA, FANCM, MSH2, NBN, NF1, PMS1, PMS2, and XPA which include only one deleterious variants. The analysis of mutation type has revealed 28 frameshift mutations, 15 stop-gain mutations, 8 missense mutations, 8 splice site variants, 1 start lost variant, and 1 synonymous variant. In total, 43 mutations were unique, 15 of them represented novel variants. Those new mutations have not been previously mentioned in the LOVD and ClinVar databases and have not been described in publications. Population frequency of all detected pathogenic mutations in 1000G, ESP6500 and ExAC databases were less than 1%. 73.8% of the mutations were available in the dbSNP database. The most common pathogenic variants were c.5329dupC and c.5341-2delA (c.5278-2delA) in BRCA1 gene, accounting for 10.7% (n = 6/56) and 8.9% of patients (n = 5/56), respectively.
Conclusions
NGS showed frequent and novel germline mutations in BRCA1/2, CHEK2, TP53 and PALB2. After the final statistical data processing, diagnostic and prevention tools for key genes will be developed and included in the National guidelines for cancer diseases.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Kazakh Institute of Oncology and Radiology Institute of General Genetics and Cytology.
Funding
The Ministry of Healthcare of the Republic of Kazakhstan.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5383 - A pilot trial to investigate the impact of a personalised self-management lifestyle programme using mobile technology on the health and wellbeing of cancer survivors
Presenter: Mary Grace Kelly
Session: Poster Display session 3
Resources:
Abstract
5084 - The BRIGHTLIGHT national survey of the impact of specialist teenage and young adult cancer care on caregivers’ information and support needs
Presenter: Rachel Taylor
Session: Poster Display session 3
Resources:
Abstract
4328 - Life beyond cancer: Occupational health care service support in returning work experienced by cancer survivals
Presenter: Minna Nurmi
Session: Poster Display session 3
Resources:
Abstract
3337 - Investigating the factors related to primary caregivers' burden in oncology patients in Greece
Presenter: Ourania Govina
Session: Poster Display session 3
Resources:
Abstract
3387 - Factors Influencing the Level of Emotional Support from Nurses Perceived by Patients Undergoing Haematopoietic Stem Cell Transplantation in Protective Isolation
Presenter: Michela Piredda
Session: Poster Display session 3
Resources:
Abstract
935 - Progressive Muscle Relaxation and Guided Imagery Techniques and the Way of Coping of Parents of Children with Malignancies: A randomized controlled trial
Presenter: Tsitsi Theologia
Session: Poster Display session 3
Resources:
Abstract
3457 - Pharmacist and Nurse Led Melanoma Immunotherapy Clinic
Presenter: Dharmisha Chauhan
Session: Poster Display session 3
Resources:
Abstract
5160 - Measuring the impact of the Irish Cancer Society's Cancer Information Services
Presenter: Aileen McHale
Session: Poster Display session 3
Resources:
Abstract
4297 - It's Great to Talk
Presenter: Noreen Andersen
Session: Poster Display session 3
Resources:
Abstract
4444 - Impact of Burn-Out Syndrome in Oncology personnel and its improvement through specific interventions
Presenter: Inmaculada Ortega
Session: Poster Display session 3
Resources:
Abstract