Abstract 124P
Background
BRAF V600E is identified approximately 5-9% of colorectal cancer (CRC) patients. Non-V600E BRAF mutation is characterized a rare molecular subtype. The clinical characteristics and prognostic impact of non-V600 BRAF mutants are not well defined.
Methods
We recruited 829 patients with CRC from our institution. Tissue samples were molecularly tested. Clinical data was retrospectively reviewed and analyzed using Chi-square and t-test. Overall survival (OS) was compared by log-rank test.
Results
All BRAF mutation was detected in 50 (6%) patients including 24 (3%) patients with non-V600 mutations. Patient characteristics and BRAF testing technique were not significantly different based on BRAF status and it was comparable between BRAF V600E and non-V600 groups. There were significantly more ALL RAS and PIK3CA mutations in non-V600 mutant patients. Patients with non-V600 mutation had median OS of 82 months which was longer than BRAF WT, 66 months, and 31 months of BRAF V600E group, respectively (P=0.067). OS according to treatment with anti-EGFR in metastatic CRC patients was not significantly different in both V600E and non-V600 BRAF mutant groups. Table: 124P
| BRAF-MT (n=50) | |||||||
| BRAF-WT (n=779) | BRAF-MT (n=50) | p-value | V600 (n=26) | non-V600 (n=24) | p-value | ||
| Age | 63 (18 - 93) | 65 (19-85) | 66 (19 - 85) | 65 (24 - 83) | |||
| Sex | |||||||
| Male | 471 (60) | 32 (64) | 0.62 | 15 (58) | 17 (71) | 0.333 | |
| Female | 308 (40) | 18 (36) | 11 (42) | 7 (29) | |||
| Sidedness | |||||||
| Left | 591 (76) | 33 (66) | 0.289 | 12 (70) | 15 (62) | 0.878 | |
| Right | 168 (22) | 15 (30) | 7 (27) | 8 (33) | |||
| non-specify | 20 (3) | 2 (4) | 1 (4) | 1 (4) | |||
| Technique | |||||||
| NGS | 547 (70) | 38 (76) | 0.466 | 18 (69) | 20 (83) | 0.26 | |
| Pyrosequencing | 84 (11) | 6 (12) | 5 (19) | 1 (4) | |||
| PCR | 148 (19) | 6 (12) | 3 (12) | 2 (12) | |||
| All RAS mutation | 418 (54) | 8 (16) | <0.001 | 0 | 8 (33) | 0.001 | |
| PIK3CA mutation | 94 (12) | 9 (18) | 0.218 | 1 (4) | 8 (33) | 0.009 | |
| Recur/Met | (n=575) | (n=35) | (n=19) | (n=16) | |||
| Anti-VEGF | 105 (18) | 7 (20) | 0.796 | 2 (11) | 5 (31) | 0.207 | |
| Anti-EGFR | 162 (28) | 6 (17) | 0.156 | 3 (16) | 3 (19) | 1 |
Conclusions
Non-V600 BRAF mutation may indicate better prognosis. The difference in treatment effect was not demonstrated in patients with BRAF mutation.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Faculty of medicine Ramathibodi Hospital.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
472P - Risk of recurrence and optimal adjuvant treatment in invasive lung adenocarcinomas manifesting as radiological part-solid nodules
Presenter: Yang Wo
Session: Poster Display
Resources:
Abstract
473P - Treatment (tx) patterns in resectable stage IA–IIIA non-small cell lung cancer (NSCLC) in China: Subgroup analysis of a global real-world (rw) study
Presenter: Chih-Chi Yang
Session: Poster Display
Resources:
Abstract
474P - The efficacy of image guided coil localisation for surgical resection of undiagnosed solitary lung nodule
Presenter: Jun Rey Leong
Session: Poster Display
Resources:
Abstract
475P - 5-year overall survival and disease free survival outcome between lobectomy and segmentectomy for early stage lung cancer in a mixed Asian population
Presenter: Jianye Chen
Session: Poster Display
Resources:
Abstract
478P - Peri-operative risks in curative lung resection of early stage primary lung cancer patients above 70 years old in a mixed Asian population
Presenter: Ian Goh
Session: Poster Display
Resources:
Abstract
480P - Aumolertinib as adjuvant therapy for resectable stage I-III EGFR-mutant NSCLC: Also effective in EGFR co-mutation
Presenter: Lin Wu
Session: Poster Display
Resources:
Abstract
481P - Comparative analysis of three NGS platforms assessing tumor mutational burden and mutational landscape in resectable non-small cell lung cancer
Presenter: Jii Bum Lee
Session: Poster Display
Resources:
Abstract
482P - Prevalence of EGFR mutations (EGFRm) and its subtypes in patients (pts) with resected stage I-III NSCLC: Results from EARLY-EGFR Singapore cohort
Presenter: Puey Ling Chia
Session: Poster Display
Resources:
Abstract
483P - Genetic profiles and evolutionary trajectory of early stage lung adenocarcinoma (AAH, AIS, MIA and IAC) revealed by multiplex sequecing
Presenter: lixuan lin
Session: Poster Display
Resources:
Abstract
484P - Treatment (tx) patterns and outcomes in resectable early-stage EGFR-mutated (EGFRm) NSCLC in South Korea: Subgroup analysis of a global real-world (rw) study
Presenter: Myung-Ju Ahn
Session: Poster Display
Resources:
Abstract