185 Background: Adolescents and Young Adults (AYAs) with cancer are at risk for poor psychosocial outcomes, in part because cancer may disrupt developmental processes such as spiritual questioning. Indeed, spirituality may enable hope, meaning, and purpose, in turn facilitating the adjustment to cancer. The need to address spirituality has been established among adult patients, how to do so in an AYA age-appropriate manner has not been described. We aimed to better understand the language and perspectives of AYAs regarding spirituality. Methods: AYA patients (ages 14-25 years) were eligible if they had been diagnosed with cancer within the past 60 days. Demographic surveys including self-reported spirituality and religiousness were completed at the time of enrollment. Semi-structured, 1:1 interviews were conducted at the time of enrollment, 6-12, and 12-18 months later. Verbatim transcripts were coded by three independent coders using directed content analysis for instances of spirituality, religiosity, hope, and fear. Additional deductive analyses used a priori coding themes defined from prior conceptualizations of AYA hope: forced effort, personal possibilities, expectations of a better tomorrow, and anticipation of a better tomorrow Results: Seventeen patients completed 44 interviews with > 100 hours of transcript-data. Their mean age was 17.1 (±2.7); 8 (47%) were male, their diagnoses were sarcoma (n = 8), acute leukemia (n = 6), and lymphoma (n = 3). At enrollment 10 (58%) & 6 (35%) endorsed personal spirituality and religiousness in surveys, respectively, few verbal narratives included explicit self-identification of either construct. Further, while many AYAs denied spiritual beliefs, all of them endorsed hopes, often as a source of strength, meaning, or self-expression. Longitudinal analyses suggested an evolution of spiritual beliefs and self-identities, even when patients selected other language to describe such processes. Conclusions: AYAs with cancer are trying to work-through complex existential beliefs and questions. Often, instead of defining themselves as spiritual or religious or using explicit spiritual language, they articulate their existential feelings with the language of hope.