Introduction

Cancer is the fifth leading cause of death for young adults (20–39 years) in the United States [1–3]. Young adults experience longer delays in diagnosis than children and older adults [4–11], and these delays are associated with diminished quality of life, increased burden of co-morbidities, and poorer survival outcomes [1, 10, 12–16]. Communication interventions hold potential to reduce these delays, but a clear understanding of the factors driving delays is essential for developing effective strategies. Due to limited routine screening for asymptomatic cancer in young people, most young adults are diagnosed only after presenting to a medical provider with symptoms [4, 17]. This reliance on individuals to recognize symptoms and seek care highlights a critical opportunity to promote earlier help-seeking through targeted communication. However, little is known about the psychological, behavioral, and structural factors that influence how young adults interpret symptoms and navigate the diagnostic process. To address this gap, we used the Model of Pathways to Treatment [18, 19] to examine cancer diagnosis delays among young adults and identify targets for earlier diagnosis and improved outcomes.

Research about young adult cancer diagnosis delays

Although research on diagnostic delays in this age group is limited, several potential barriers to timely diagnosis have been identified, including structural, provider-level, and individual-level factors. Among structural determinants, living in a rural (versus metro) location and being uninsured or underinsured are associated with young adult delays [20–30]. Medical providers’ lack of awareness that symptoms could be cancer, or attribution of symptoms to lifestyle causes, may also lengthen diagnosis timelines [31, 32].

Individual-level factors can contribute to prolonged diagnostic journeys; however, most research had been conducted outside the US where healthcare access conditions differ. For example, a study in the United Kingdom (UK) found that 27% of adolescents and young adults who were diagnosed with cancer waited more than one month to seek help for their symptoms [6]. In several qualitative studies, young adults with cancer believed their pre-diagnosis lack of cancer symptom knowledge and feeling of invincibility contributed to not seeking medical care sooner [31, 33–35]. Additional UK-based research identified practical and emotional barriers to timely care-seeking, including challenges of missing school or work for appointments, competing priorities with family, and worries or fears associated with talking to a doctor [36–38]. US-based research on care-seeking and diagnosis delay in this population remains scarce, though one study examining a related construct, time to treatment, found that young adults with Hodgkin lymphoma experienced longer delays than adolescents, attributed in part to the competing work and family responsibilities characteristic of this life stage [39].

While these findings provide useful insights into young adult behavior in other countries and contexts, and some US-based research has explored how older adults make decisions to seek care, little is known about how these processes unfold specifically for young adults in the US. This gap warrants further investigation given the key developmental, psychological, and situational differences between young adults and older populations. Moreover, young adults aged 20–39 represent a distinct subgroup within the broader adolescent and young adult (AYA) population (ages 15–39), as they differ from adolescents in cancer type distribution and in their need to navigate adult medical systems [11]. Distinct characteristics of young adulthood, such as emerging autonomy [25], growing education, work and family responsibilities [40], and increased reliance on online health information [41], may influence how symptoms are interpreted and when care is sought.

The model of pathways to treatment

The Model of Pathways to Treatment [18, 19] divides the pathway to diagnosis into four time periods. The appraisal interval begins when an individual detects a bodily change (e.g., vision changes, blood in stool, etc.) and involves assessing whether that change represents a normal fluctuation or an abnormal symptom, sometimes drawing on non-clinical sources such as online searches or conversations with others. The interval ends when the individual perceives the symptom as warranting consultation with a healthcare provider, though some may dismiss symptoms as nonserious or attempt to self-manage them before reaching that point. The help-seeking interval begins when an individual perceives a need for consultation with a healthcare provider and involves making decisions about contacting a provider to discuss symptoms. Challenges such as lack of insurance, inability to miss work, or absence of a routine provider may prolong this interval or motivate a return to symptom self-appraisal. The diagnostic interval begins at the point of first discussion with a healthcare provider and continues until a formal, accurate disease diagnosis is made. This interval encompasses all provider encounters, referrals, misdiagnoses, and provider-recommended symptom management strategies that may occur before a diagnosis is reached. The final interval, pre-treatment, is outside the scope of diagnosis delay research.

The Model of Pathways to Treatment is well suited to guide the present analysis because it outlines general events and stages that can be applied to any disease or population and has been well established for studying cancer diagnosis delays [42–46]. The model’s intervals and processes are supported with empirical findings. A UK study of 7,543 adults used the Model of Pathways to Treatment to help identify several significant barriers to medical care seeking for potential cancer symptoms during COVID-19 [47]. Another study used the model to identify predictors of delayed breast cancer diagnosis and treatment in South African women [42]. A nationally representative assessment of US adults’ reasons for avoiding medical care found multiple barriers consistent with processes and factors outlined in the Model of Pathways to Treatment [48].

Study aims

We asked three research questions about delays in time to diagnosis (i.e., the time from detecting a bodily change to disease diagnosis) for young adult cancer survivors:What prolongs the appraisal interval? Specifically, what appraisal and self-management processes and determining disease, patient, and health care system factors contribute to delays between noticing bodily changes and perceiving the need to consult a healthcare provider?What prolongs the help-seeking interval? Specifically, what decision-making processes and determining disease, patient, and health care system factors contribute to delay between perceiving the need to consult a healthcare provider and consulting a healthcare provider for the first time?What prolongs the diagnostic interval? Specifically, what health care experiences and determining disease, patient, and health care system factors contribute to delay between first healthcare provider consultation and formal cancer diagnosis?

Understanding young adult experiences within each of these three intervals will highlight potential opportunities for shortening the total time to diagnosis duration through communication interventions.