103 Background: Community health centers’ (CHCs) patients newly diagnosed with cancer often experience barriers to accessing timely treatment. Patient navigation decreases barriers to cancer screening and diagnostic care, but the exact impact on cancer treatment is unclear. We implemented patient navigation to provide underserved patients with support to access and adhere to cancer treatment. The goal of our study is to determine the effect of patient navigation on missed appointment rates, treatment adherence, and health outcomes among an underserved patient population. Here, we present preliminary data about program implementation. Methods: Utilizing a population health registry, TopCare, and referrals from CHCs physician champions, newly diagnosed cancer patients from Massachusetts General Hospital CHCs were referred to the Cancer Center, identified and verbally consented to participate in the study’s intervention. Patients are randomized either to receive in-person patient navigation or enhanced usual care, which consists of two reminder phone calls prior to each oncology appointment. Adherence to treatment, healthcare utilization, patient satisfaction with cancer care and patient navigation, patient engagement, financial burden, symptom burden, health-related quality of life, and psychosocial care are longitudinally assessed. Our primary outcome is missed appointment rate to oncology appointments. Results: The trial started in November 2017 and as of April 2021, we have identified 349 eligible patients and enrolled 261 (82% consent rate for reached patients). Of 261 enrolled patients, 50% were women, 38% identified as non-White, 25% identified as Hispanic or Latino, and 28% did not speak English. The most frequent cancer types enrolled include genitourinary (n=67), thoracic (n=47), gastrointestinal (n=47), and breast (n=46). Patients had 6257 visits and 195 were missed (3.1%). Navigators performed 4553 interventions. There were 152 emergency department visits and 127 unplanned hospital admissions. Of 120 referrals to supportive care, 54 were to social work, 38 to palliative care and 28 to Psychiatric Oncology or behavioral health. Conclusions: Patient navigation is feasible for underserved CHC patients newly diagnosed with cancer. Our current missed appointment rate is 3.1%, including the time period of the COVID-19 pandemic. After trial completion in July 2021, we will compare the outcomes in patients who received in-person patient navigation to patients who were randomized to enhanced usual care. Clinical trial information: NCT03226405.