Abstract 3364
Background
RAS mutational status is an essential criterion to guide first-line treatment in metastatic colorectal cancer (mCRC). MORE-RAS was a multicenter, multicountry, observational, ambispective (retrospective + prospective) study conducted in the Middle East and North Africa (MENA) region to assess RAS testing practices and tumor characteristics in newly diagnosed patients (pts) with mCRC. Results of the retrospective analysis are presented here.
Methods
Eligible pts included adults aged ≥18 with mCRC who had already initiated first-line therapy, had at least 1 post-baseline visit for disease evaluation, and had available survival data. Pts with incomplete and unavailable data or presence of other coexisting malignancies were excluded. Data from eligible pts were retrospectively analysed 2 years back from the day of patient consent.
Results
A total of 495 pts (median age: 57 y) were enrolled; majority were male (55.6%), with adenocarcinoma histology, stage IV disease (86.8%) and left-sided tumors (79%). Primary tumor site was sigmoid (40.9%), followed by rectal (26.1%), ascending (17.2%), descending (12.1%), and transverse (3.8%) colon. RAS testing was requested in 417 (78%) pts; reasons for not prescribing included test unavailability, financial/medical decision, or other. Testing samples were mostly paraffin-embedded (91.7%) primary tumors (92.5%); sequencing was the most common test method used. RAS testing found that 33.9% of tumors harbored mutations and 66.1% carried wild-type (WT) sequences. The most common mutation was KRAS (94.1%), occurring largely in Exon2-Codon12 (70.5%). RAS testing was typically prescribed after initiation of first-line treatment, significantly more in pts with stage IV disease (p < 0.005), resulted in addition of targeted therapy (41.8% anti EGFR, 30.2% anti VEGF) in WT mCRC, and significantly impacted treatment strategy of left-sided tumors (p = 0.037).
Conclusions
RAS testing for mCRC in the MENA region was often performed after first-line treatment. The dominance of WT RAS in this region is distinct from the mutational pattern reported in Western countries.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Amgen.
Funding
Amgen.
Disclosure
M. Oukkal: Advisory / Consultancy, Speaker Bureau / Expert testimony: Amgen; Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (self): Roche; Advisory / Consultancy: Novartis; Advisory / Consultancy: Pfizer; Speaker Bureau / Expert testimony: Bayer; Speaker Bureau / Expert testimony: Ipsen. H. Mahfouf: Advisory / Consultancy, Speaker Bureau / Expert testimony: Amgen; Advisory / Consultancy, Speaker Bureau / Expert testimony: Roche; Advisory / Consultancy, Speaker Bureau / Expert testimony: Merck; Advisory / Consultancy, Speaker Bureau / Expert testimony: Bayer; Advisory / Consultancy: Ipsen. A. Ouamer: Full / Part-time employment: Amgen. L. Bashir: Full / Part-time employment: Amgen. All other authors have declared no conflicts of interest.
Resources from the same session
5295 - Predictive factors and survival outcomes with stereotactic body radiation therapy in treatment of oligometastases in colorectal cancer
Presenter: Vibhay Pareek
Session: Poster Display session 2
Resources:
Abstract
5887 - Factors of importance in procuring tumoroids from colorectal liver metastasis biopsies for precision medicine.
Presenter: Lars Henrik Jensen
Session: Poster Display session 2
Resources:
Abstract
2196 - FUSAFE individual patient data meta-analysis (MA) to assess the performance of dihydropyrimidine dehydrogenase (DPD) gene polymorphisms for predicting grade 4-5 fluoropyrimidine (FP) toxicity
Presenter: Marie-Christine Etienne-Grimaldi
Session: Poster Display session 2
Resources:
Abstract
2859 - Treatments (tx) after progression to first-line FOLFOXIRI + bevacizumab (bev) in metastatic colorectal cancer (mCRC) patients (pts): A pooled analysis of TRIBE and TRIBE-2 studies by GONO.
Presenter: Daniele Rossini
Session: Poster Display session 2
Resources:
Abstract
3888 - Randomized phase III study of sequential treatment with capecitabine or 5-fluorouracil (FP) plus bevacizumab (BEV) followed by the addition with oxaliplatin (OX) versus initial combination with OX+FP+ BEV in the first-line chemotherapy for metastatic colorectal cancer: The C-cubed study
Presenter: Takeshi Nagasaka
Session: Poster Display session 2
Resources:
Abstract
1065 - Early tumour shrinkage (ETS), depth of response (DpR) and associated survival outcomes in patients (pts) with RAS wild type (WT) metastatic colorectal cancer (mCRC) classified according to Köhne prognostic category: retrospective analysis of the panitumumab (Pmab) PRIME study
Presenter: Andrea Sartore-Bianchi
Session: Poster Display session 2
Resources:
Abstract
1702 - Randomized phase II trial of CAPOX with planned oxaliplatin stop-and-go strategy as adjuvant chemotherapy after curative resection of colon cancer (CCOG-1302 study)
Presenter: Hiroyuki Yokoyama
Session: Poster Display session 2
Resources:
Abstract
5104 - A metabolomic recurrence score for risk-stratification of elderly patients (pts) with early colorectal cancer (eCRC)
Presenter: Samantha Di Donato
Session: Poster Display session 2
Resources:
Abstract
5285 - RAS mutant allele fraction in plasma predicts benefit to anti-angiogenic based first line treatment in metastatic colorectal cancer
Presenter: Giulia Martini
Session: Poster Display session 2
Resources:
Abstract
1790 - Impact of prophylactic systemic antibiotics (SA) on outcome of patients (pts) with RAS-wildtype (RAS-wt) metastatic colorectal carcinoma (mCRC) treated with cetuximab-based first-line therapy. Subgroup analysis of the german non-interventional study ERBITAG
Presenter: Stephan Sahm
Session: Poster Display session 2
Resources:
Abstract