Other Oncogene Mutations for Anti-EGFR Efficacy in Patients With Left-sided RAS-wild Type Metastatic Colorectal Cancer

In total, the study plans to include 355 patients diagnosed with unresectable metastatic colorectal cancer with a left-sided localization of the primary tumor, who have not previously received systemic therapy for metastatic disease, have wild-type KRAS/NRAS/BRAF, or have wild-type KRAS/NRAS with unknown BRAF status in no contraindications to targeted therapy (cetuximab/panitumumab/bevacizumab). Patients meeting the inclusion criteria will be randomized 1:1 into Cohort A (n ≈ 177) or Cohort BC (n ≈ 177). Cohort A is the control: patients receive combination chemotherapy with FOLFOX plus anti-EGFR therapy (panitumumab or cetuximab) based on RAS/BRAF wild-type data, according to clinical guidelines. Next, this cohort, after completion of the protocol, undergoes extended profiling, according to the results of which it is divided into cohorts A1 and A2. Cohort A1 includes patients without changes in alternative oncogenes (N ≈ 120), cohort A2 includes patients with changes (N ≈ 40). The BC cohort begins FOLFOX chemotherapy and simultaneously undergoes extensive molecular genetic profiling. Further, the BC cohort, depending on the profile, is divided into cohort B - patients without changes in alternative oncogenes, and cohort C - with changes in alternative oncogenes. The expected cohort ratio is 3:1 (\~120 and \~40 patients). Cohort B begins to receive anti-EGFR therapy in addition to chemotherapy, and the potentially resistant cohort C continues to receive chemotherapy alone or begins to receive bevacizumab if there are no contraindications.