The use of Artificial Intelligence (AI) in healthcare is expanding rapidly, including in oncology. Although generic AI development and implementation frameworks exist in healthcare, no effective governance models have been reported in oncology. Our study reports on a Comprehensive Cancer Center's Responsible AI governance model for clinical, operations, and research programs. We report our one-year AI Governance Committee results with respect to the registration and monitoring of 26 AI models (including large language models), 2 ambient AI pilots, and a review of 33 nomograms. Novel management tools for AI governance are shared, including an overall program model, model information sheet, risk assessment tool, and lifecycle management tool. Two AI model case studies illustrate lessons learned and our "Express Pass" methodology for select models. Open research questions are explored. To the best of our knowledge, this is one of the first published reports on Responsible AI governance at scale in oncology.