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Head and neck cancer radiotherapy requires highly precise dose delivery to ensure tumor control while sparing nearby critical structures, but daily anatomical changes such as tumor shrinkage, weight loss, and setup variability often degrade treatment accuracy. Although cone-beam CT provides valuable daily imaging, current adaptive radiotherapy workflows remain largely manual, time-consuming, and infrequent, limiting their ability to respond to ongoing anatomical changes and often resulting in suboptimal target coverage or increased toxicity risk. To address these limitations, we propose a deep reinforcement learning framework for fully automated daily treatment adaptation using cone-beam CT and dosimetric constraints. The problem is formulated as a sequential decision-making task in which an agent adjusts beam parameters based on evolving patient anatomy, cumulative dose, and constraint satisfaction. The state includes daily imaging and dose history, the action space involves fluence or multileaf collimator adjustments, and the reward function balances target coverage, organ-at-risk sparing, and plan stability. A patient-specific simulator based on historical imaging enables training without real-time patient interaction. This framework enables continuous, personalized, and automated plan adaptation that directly responds to anatomical changes while maintaining clinical safety constraints. By leveraging long-horizon optimization, the system can outperform static planning strategies and better manage stochastic anatomical variations in head and neck cancer treatment. Overall, this approach provides a foundation for closed-loop adaptive radiotherapy that could improve treatment accuracy, reduce toxicity, and reduce reliance on manual planning.

Prolonged mechanical ventilation (PMV), affecting 5–15% of ICU patients, is associated with high mortality (30–50%), long-term disability, and substantial healthcare costs exceeding $100,000 per admission. These patients often require extended respiratory support beyond 14–21 days and consume significant ICU resources. Current weaning strategies rely on fixed spontaneous breathing trial (SBT) criteria (e.g., RSBI thresholds, oxygenation, respiratory rate), which fail to account for the heterogeneous and evolving physiology of PMV patients. This reduces weaning to discrete events rather than a continuous adaptive process. We propose reinforcement learning from human feedback (RLHF) as a superior framework for weaning, enabling AI systems to learn sequential decision-making policies from clinician preferences across patient trajectories. Traditional protocols ignore temporal dependencies such as prior SBT outcomes, sedation exposure, and respiratory muscle trends. While standard reinforcement learning supports sequential optimization, it depends on difficult-to-define reward functions. RLHF overcomes this by learning reward signals directly from clinician comparisons, aligning model behavior with real-world clinical judgment. Research should shift toward RLHF-based dynamic weaning policies rather than static prediction models. Clinical stakeholders should support data collection and prospective evaluation of RLHF-guided weaning versus standard protocols. RLHF offers a necessary advancement for personalized PMV weaning, addressing limitations of rigid protocols and improving alignment with clinical decision-making.