Abstract 522P
Background
BRAF mutations have been functionally categorized into 3 different classes that have variable levels of RAS dependency. Prevalence and prognosis varied significantly across different tumor types and histology. In attempt to explore clinical characteristics, co-mutation situation and prognosis of patients with solid tumors associated with different BRAF mutations in our database.
Methods
In the retrospective study, genomic profiling was performed on tissue and plasma samples of 26115 patients, using NGS from Feb 2019 to Dec 2023. 183 patients with NGS-detected haboring BRAF V600E mutations were included in the study. Baseline of patients, tumor, NGS, co-mutation at enrolment, and treatment and outcome data at routine follow up.
Results
• BRAF mutation rate in patients with malignant solid tumors was 0.70% (183/26115). Cancer types consisted of lung cancer (n = 136, 74.3%), colorectal cancer (n = 20, 10.9%), thyroid cancer(n=9, 4.9%), malignant melanoma (n = 6, 3.3%), biliary tract cancer (n = 3, 1.6%), and others (n=9, 4.9%). • BRAF mutations include 92 class I (50.3%, 92/183), 42 class II (22.9%, 42/183), 34 class III (18.6%, 34/183). In addition, 8 cases (4.4%, 8/183) remained unclassified. • The overall survival (OS) of class I was 58.21 (± 6.30, 95% CI) months, class II was 37.00 (± 0.99, 95% CI) months, and class III was 41.95 (± 2.95, 95% CI) months, respectively. • Furthermore, the most common co-mutation is TP53 (19.64%, 33/168), EGFR (8.93%, 15/168), promoter TERT mutations (8.93%, 15/168), and PIK3CA (7.74%, 13/168). Patients with TP53 co-mutation demonstrate shorter OS benefit (35.43±2.56 months vs 65.86±3.03 months, p=0.066).
Conclusions
This study captures precision oncology data enable further insights into clinical decision making, BRAF class I mutations have the highest proportion of mutations, also best overall survival. TP53 is the most common co-mutation, following by EGFR, TERT and PIK3CA. Our study indicates that the class of the BRAF mutation may have clinical implications and genomic profiling which should be defined in the clinical practice and used to guide therapeutic decisions.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.