Hye Sung Kim, Carly Irwin, Arjun S. Ulag, Siddhartha Devarakonda
As the population of individuals with limited English proficiency (LEP) continues to rise in the United States, language barriers have become an increasingly important yet underrecognized driver of disparities in cancer care. This review aims to synthesize current evidence on how LEP affects the cancer care continuum and to offer actionable strategies to promote equity. We conducted a comprehensive review of the literature spanning communication, diagnosis, treatment, outcomes, prevention, research participation, and policy related to LEP populations in oncology. LEP is associated with poorer cancer outcomes, including delayed diagnosis, lower treatment adherence, decreased access to supportive services, and reduced quality of life. These disparities stem from multilevel communication barriers, underuse of professional interpretation, cultural discordance, and limited institutional support for language-concordant care. LEP patients are also underrepresented in cancer research due to language-based exclusion criteria, inadequate translation resources, and provider burden. A multifaceted framework is needed to address LEP-related disparities in oncology. Key strategies include expanding language-concordant care teams, improving interpreter and translation services, designing inclusive research protocols, and embedding language equity into institutional safety culture and policy. Addressing these disparities is a clinical, ethical, and public health imperative requiring systemic investment and leadership.