Testing the Use of BRAF-Targeted Therapy After Surgery and Usual Chemotherapy for BRAF-Mutated Colon Cancer

Inclusion Criteria: * PRE-REGISTRATION (STEP 0) ELIGIBILITY CRITERIA: * BRAF V600 mutational status may be determined either locally or by central testing. This testing is mandatory prior to registration to determine eligibility. Tissue submission should be initiated as soon after surgery as possible. For tumors evaluated at local laboratories, formalin-fixed paraffin-embedded (FFPE) tumor tissue must still be submitted for central confirmation of BRAF status * REGISTRATION (STEP 1) ELIGIBILITY CRITERIA: * Histologically-proven stage III (any T \[Tx, T1, T2, T3, or T4\], N1-2M0; includes N1C) or high-risk (pT4) stage II colon adenocarcinoma. Tumors must be deemed to originate in the colon including tumors that extend into/involve the small bowel (e.g. those at the ileocecal valve) and must have been completely resected * BRAF V600E mutation * MMR proficient (pMMR) or microsatellite stable (MSS) tumor * Histologic documentation: adenocarcinoma * Stage: III (any T \[Tx, T1, T2, T3, or T4\], N1-2M0; includes N1C) or high-risk II (pT4) * Tumor site: colon * Patients must have received at least 3 months of adjuvant chemotherapy with either leucovorin calcium, fluorouracil, and oxaliplatin (FOLFOX) (minimum of 5 cycles) or capecitabine and oxaliplatin (CAPOX) (minimum of 3 cycles) * Adjuvant therapy must be completed at most 8 weeks prior to registration * No other prior medical therapy (chemotherapy, immunotherapy, biologic, or targeted therapy) or radiation therapy for the curre…