Meme Kanseri Vakalarında BRCA1 ve BRCA2 Varyantlarının Spektrumu: Tek Merkez Deneyimi

Year 2025, Volume: 14 Issue: 3, 628 - 634, 31.10.2025

Zeynep Esener , Seray Saray , Yakup İriağaç , Dilan Genç Akdağ , Hilmi Bolat

Abstract

Amaç: Kalıtsal meme kanserleri, tüm meme kanserlerinin yaklaşık %5 ila %10’unu oluşturur ve bu vakaların önemli bir kısmı BRCA1 ve BRCA2 genlerindeki patojenik değişimlerle ilişkilidir. Bu genlerdeki varyantların tespiti, risk değerlendirmesi ve klinik kararlar için kritiktir. Bu çalışmanın amacı meme kanseri tanısı almış hastalarda BRCA1 ve BRCA2 ilişkili kalıtsal meme kanserinin klinik spektrumu ve bölgesel varyant profili incelenerek literatüre katkı sağlamaktır. Gereç ve Yöntem: Aralık 2023 – Şubat 2025 tarihleri arasında Balıkesir Üniversitesi’nde değerlendirilen 128 meme kanseri olgusuna yeni nesil sekanslama yöntemi kullanılarak analiz edilen BRCA1 ve BRCA2 varyantları retrospektif olarak incelendi. Patojenik varyant saptanmayanlarda çoklu ligasyon bağımlı prob amplifikasyonu (MLPA) testi sonuçları değerlendirildi. Bulgular: 128 hastanın 18’inde (%14.06) BRCA1 ve BRCA2 de patojenik/olası patojenik varyantlar bulundu. 12 hastada (%9.3) patojenik/olası patojenik varyantlar eşit dağılım gösterdi. 6 hastada (%4.7) belirsiz klinik öneme sahip varyantlar saptandı. Bir hastada (0.78%) BRCA1 ekzon 8 delesyonu tespit edildi. Sonuç: Çalışmamız, BRCA varyantlarının dağılımını ulusal ve uluslararası verilerle uyumlu olarak ortaya koymaktadır. Kalıtsal meme kanseri hastalarına genetik danışmanlık verilmesi, yakın akrabaların taranması ve varyantların düzenli değerlendirilmesi erken tanı ve etkili yönetim için önemlidir.

Keywords

Meme Kanseri , BRCA1 , BRCA2

Spectrum of BRCA1 and BRCA2 Variants in Breast Cancer Cases: A Single-Center Experience

Abstract

Objective: Hereditary breast cancers comprise approximately 5–10% of all breast cancer cases, with a significant portion linked to pathogenic alterations in the BRCA1 and BRCA2 genes. Detecting these variants is critical for risk assessment and clinical decision-making. The aim of this study is to contribute to the literature by examining the clinical spectrum and regional variant profile of BRCA1 and BRCA2-related hereditary breast cancer in patients diagnosed with breast cancer. Materials and Methods: A total of 128 breast cancer patients evaluated at Balıkesir University between December 2023 and February 2025 were analyzed for BRCA1 and BRCA2 variants using next-generation sequencing retrospectively. Multiplex ligation-dependent probe amplification (MLPA) testing results were evaluated for cases without pathogenic variants. Results: Pathogenic/likely pathogenic variants in BRCA1 and BRCA2 were found in 18 patients (14.06%). Pathogenic/likely pathogenic variants were detected in 12 patients (9.3%) with equal distribution between the two genes. Variants of uncertain significance were identified in 6 patients (4.7%). One patient had a deletion in exon 8 of BRCA1. Conclusion: Our study reveals the distribution of BRCA variants consistent with national and international data. Providing genetic counseling, screening first-degree relatives, and regular re-evaluation of variants are essential for early diagnosis and effective management of hereditary breast cancer

Keywords

: Breast Cancer , BRCA1 , BRCA2

Ethical Statement

Institution: Balikesir University Ethics Committee Date: 11.03.2025 Approval no: 2025/124

Supporting Institution

No funding was received for this study.

Thanks

The authors would like to extend their sincere thanks to anyone who contributed to this study.

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