TURKISH JOURNAL OF ONCOLOGY 2017 , Vol 1 , Num 3
The Frequency and Management of TP53 Mutation Carriers in Turkish Patients with BRCA-Negative Breast Cancer Under 50 Years of Age
Taha Reşid ÖZDEMİR1,Özge ÖZER KAYA1,Mustafa EMİROĞLU2,Kadri Murat ERDOĞAN1,Mustafa DEĞİRMENCİ3,Merve SAKA GÜVENÇ1,Gönül DEMİR4,Altuğ KOÇ1,Berk ÖZYILMAZ1,Özgür KIRBIYIK1
1Health Sciences University İzmir Tepecik Training and Research Hospital, Genetic Diagnostic Center, İzmir-Turkey
2Department of General Surgery, Health Sciences University İzmir Tepecik Training and Research Hospital, İzmir-Turkey
3Department of Medical Oncology, Health Sciences University İzmir Tepecik Training and Research Hospital, İzmir-Turkey
4Department of Radiation Oncology, Health Sciences University İzmir Tepecik Training and Research Hospital, İzmir-Turkey
DOI : 10.5505/tjo.2020.2107 OBJECTIVE
Germline mutations in the TP53 gene cause Li-Fraumeni Syndrome (LFS). Breast cancer (BC) is the most common cancer that is seen in young women with LFS. The majority of BC in LFS occurs between 15 and 44 age of years. The present study aims to determine the frequency of TP53 gene germline mutation carriers in Turkish patients with BRCA-negative BC under 50 years of age as the first study from Turkey, to our knowledge, and to emphasize the importance of management in TP53 gene mutation carriers.

METHODS
One hundred patients with BRCA-negative BC younger than 50 years old were evaluated concerning mutations in the TP53 gene between 2016 and 2017 years. Sequencing analysis using targeted next-generation sequencing (NGS) and deletion/duplication analysis using multiplex ligation-dependent probe amplification (MLPA) method were performed in TP53 gene in all patients.

RESULTS
Five variants were identified in five of 100 patients (5%) in this study. Four of them were evaluated as known as pathogenic/likely pathogenic (4%; 4/100). One variant was evaluated as a variant of uncertain clinical significance (VUS).

CONCLUSION
The patients with BRCA-negative BC younger than 50 years old should be evaluated concerning TP53 gene mutations because of increased lifetime risk of various developing cancer. Appropriate genetic counseling should be given to patients with TP53 gene mutations, and the follow-up of these patients should be provided multidisciplinary. Keywords : BRCA-negative breast cancer; early-onset; Li-Fraumeni syndrome; molecular analysis; TP53 gene