Head and neck cancer patients often experience severe side effects during treatment, which for many subside over time. However, some continue to suffer from persistent late toxicity, sig- nificantly diminishing their quality of life. To better anticipate these outcomes, we analyzed data from a weekly symptom-reporting questionnaire called the MDASI-HN, collected both during and after treatment. Using advanced deep learning methods, specifically Long Short-Term Memory (LSTM) networks, we addressed the challenges of missing responses and subjective symptom rat- ings to predict late toxicity 12 months post-treatment. We then combined these predictions with other clinical information to build a “Symptom Burden Model”, ultimately improving our ability to predict overall survival outcomes. Our findings show that incorporating patient-reported symptom data into survival models substantially enhances prediction accuracy, highlighting the potential of patient-centered data to improve treatment decisions and long-term care for head and neck cancer patients.