While head and neck cancer (HNC) is highly curable, primary radiation treatment (RT) is nonetheless challenging. Despite intensive, high-quality, multidisciplinary symptom management of HNC patients during radiation, up to 80% of HNC patients experience moderate to severe levels of oral microsites making it nearly impossible to drink sufficient fluids and necessitating opioid care for pain. Our data show that 27-32% of HNC patients are admitted to inpatient or emergency room (ER) units during RT. Those admissions related to dehydration (and the accompanying costs) are largely preventable, provided at-risk patients can be identified early for intravenous fluid rehydration. Currently, given standard of care for HNC patients undergoing RT, clinicians assess patients only once per week during standard clinic visits. However, the physiological changes underlying the onset of dehydration can develop rapidly, often between clinic visits. In the proposed project, we focus on this missed opportunity for prevention by testing the efficacy of a novel method for home- based dehydration assessment and early intervention to reduce dehydration risk. This project will assess the efficacy of a coordinated dehydration prevention program using a system (CYCORE) that links home-based monitoring sensors-that collect biometric and self-reported symptom data-to a cyber-infrastructure (CI) and sends these data daily to the patient's healthcare team, who in turn monitor the patients for early signs of dehydration and provide earlier clinical intervention, whenneeded. It is based on our successful pilot study that evaluated the feasibility of CYCORE use in HNC patients and their radiology healthcare team. The patients reported high acceptability of the system, while clinicians perceived the data as valuable and useful in providing additional information regarding patient's at-home dehydration status. We will randomize a total of 192 HNC patients receiving RT at MD Anderson Cancer Center (MDACC) to either standard care or CYCORE. We hypothesize that patients randomized to CYCORE will experience fewer hospitalizations and ER admissions (and fewer associated costs) due to dehydration compared with patients in the standard care arm. To the best of our knowledge, the application of a system such as CYCORE has not been explored in the HNC population. Objective, home-based monitoring may be an optimal method of capturing data critical to early evaluation of dehydration risk; other methods, such as patient self-report, are limited by the patient's ability o accurately recall symptoms. MDACC is an ideal environment for conducting the proposed study; more HNC patients are treated with RT at MDACC compared with any other center in Texas, and it is possible to track outcomes and cost-related data, given that HNC patients receive all of their RT-related care, including related hospitalization and ER admissions, at one center. If our efficacy study proves successful, this dehydration prevention model can potentially be applied to other health conditions and in other settings.