Patients with cancer often spend several hours on a single day attending ambulatory care appointments, including clinic visits, lab tests, imaging, and infusions. A study conducted at an urban cancer center found that the median time spent on ambulatory care, including clinic time, travel, and parking, was 197 minutes (143-287 minutes). For example, a lab-only visit took about 99 minutes, while a visit involving a clinician, labs, and infusion took 278 minutes. These findings highlight the substantial time burden of cancer care, which can be considered "lost days" due to the time required for multiple services and travel. The study used real-time location system data to track clinic times and estimated travel and parking times. The results emphasize the need to account for these time burdens in healthcare systems, as they significantly impact patients' daily lives and may affect employment and financial stability. The study also suggests that improving care coordination, using telehealth, and reducing unnecessary trips could help alleviate these time burdens. The findings support the inclusion of ambulatory care days in the measurement of overall healthcare contact days. The study had limitations, including its single-center design and potential underestimation of travel times. Overall, the results underscore the importance of addressing time-related challenges in cancer care to improve patient outcomes and quality of life.Patients with cancer often spend several hours on a single day attending ambulatory care appointments, including clinic visits, lab tests, imaging, and infusions. A study conducted at an urban cancer center found that the median time spent on ambulatory care, including clinic time, travel, and parking, was 197 minutes (143-287 minutes). For example, a lab-only visit took about 99 minutes, while a visit involving a clinician, labs, and infusion took 278 minutes. These findings highlight the substantial time burden of cancer care, which can be considered "lost days" due to the time required for multiple services and travel. The study used real-time location system data to track clinic times and estimated travel and parking times. The results emphasize the need to account for these time burdens in healthcare systems, as they significantly impact patients' daily lives and may affect employment and financial stability. The study also suggests that improving care coordination, using telehealth, and reducing unnecessary trips could help alleviate these time burdens. The findings support the inclusion of ambulatory care days in the measurement of overall healthcare contact days. The study had limitations, including its single-center design and potential underestimation of travel times. Overall, the results underscore the importance of addressing time-related challenges in cancer care to improve patient outcomes and quality of life.