The COVID-19 pandemic and concomitant lockdown across the US has forced sudden and unplanned changes in cancer patient care. A majority of cancer patients are older and immunocompromised while undergoing treatment, which presents a difficult challenge for oncologists and surgeons trying to decide how to continue the best care for their patients while minimizing the risk of infection with SARS-CoV-2. Simultaneously, the ability of patients to adhere to treatment recommendations, and to deal with cancer treatment induced side effects and various co-morbidities, has also been severely affected by the consequences of the COVID-19 pandemic. Many patients lost their usual infrastructure to handle their care, and many may have altered their behaviors towards treatment due to fear, lack of resources, or financial instability. The overall impact of ongoing changes in cancer treatment patterns, and changes in patient adherence to ongoing treatment due to COVID19 is yet to be defined. Early numbers from the American Cancer Society Cancer Action Network show that close to 80% of patients in active treatment for cancer experienced a delay in their healthcare, including 17% that reported to their cancer therapy. We propose to evaluate the impact of the COVID-19 pandemic on cancer care delivery among diverse populations, particularly those mostly affected by this outbreak, which include Blacks and Hispanics. We propose to identify and evaluate the impact of ongoing changes in cancer treatment, and changes in patient adherence to treatment among diverse populations, with the long-term goal of learning from this experience to better serve cancer patients moving forward as this pandemic continues its course. The pandemic imposed changes in cancer treatment protocols and survivorship follow-up to accommodate stay-at-home requirements, new hospital protocols to reduce infection rates, and for the protection of vulnerable cancer patients. Many of these changes may prove to be as effective as the standard of care, some may not. We propose to conduct a mixed-methods study within the Norris Comprehensive Cancer Center (NCCC) clinics, focusing on two of the priority cancers for our catchment area with high volume in our clinics: breast (BrCa) and lung cancer (LCa), focusing on identifying changes in cancer treatment for these two cancers from the start of the COVID-19 pandemic in March 2020 until September 2020, in comparison with the same time period in 2019 (Aim 1). We propose to identify treatment changes and evaluate their impact on short-term outcomes 12 months post-treatment. Given the diversity of our patient population, we are uniquely positioned to identify disparities in cancer treatment outcomes and adherence to treatment among minority populations, particularly Hispanics who constitute ~40% of our patient population. To enhance our reach and understanding of the impact of COVID-19 among Black cancer patients, we are leveraging the Florida-California Cancer Research Education and Engagement (CaRE2) Health Equity Center Community Outreach Core, which is focused on community outreach and engagement among Blacks and Hispanics in Florida and California, and will allow us to include a large Black patient population.