171 Background: Serious mental illness (SMI), defined as a mental, behavioral, or emotional disorder resulting in serious functional impairment, that substantially interferes with or limits one or more major life activities, includes schizophrenia, bipolar disorder, and major depression. Patients with SMI and cancer have poor survival rates attributed to inequities in cancer care. Such patients are often diagnosed at an advanced stage and are more likely to have their cancer care interrupted. This study surveyed the general practices oncologists apply to integrate mental health and cancer care in their clinical practice. The study also surveyed perspectives on personalized collaborative care intervention to improve cancer outcomes in patients with SMI while identifying the barriers to adapting such intervention in clinical settings. Methods: In February and March 2024, US-based hematologists/oncologists convened at live meetings to discuss abstracts presented at the 2023 ASCO Quality Care Symposium. An online premeeting survey was used to collect participants’ demographics. Participants’ approach to mental health care for patients with cancer were captured via an audience response system during the live meetings. Responses were aggregated and analyzed using descriptive statistics. Results: Among 125 participants, 77% were community providers. The majority of participants (60%) reported frequently discussing mental health with their patients with cancer. Respondents support the mental health needs of their patients with cancer by utilizing in-house social workers (52%) or in-house counseling services (31%), or by referring to in-house clinical psychologist (40%) or an external psychiatrist (41%). They identified challenges to integrating mental health care into cancer treatment: lack of dedicated staff (54%), high patient volume (44%), and lack of available psychosocial tools (40%). Additionally, a subset of participants was asked about their perspectives on collaborative care intervention for cancer care of patients with SMI, and while most participants were encouraged, they also reported that mental health services should be coordinated primarily through either a psychiatrist (25%) or a social worker (25%). Interestingly, limited access to psychiatric care (78%) and lack of resources to screen patients for SMI (56%) were the primary barriers to adapting a personalized and collaborative care approach in the real-world setting. Conclusions: Participants were inclined to incorporate personalized mental health assessments into routine clinical care for their patients with cancer, however they face several barriers to implementation. Further research is needed to address those modifiable barriers and assess the impact of a personalized and collaborative care approach on timely diagnosis and mitigating inequities in cancer care to improve cancer outcomes in patients with SMI.