Impact of age on financial toxicity among breast cancer patients with resectable invasive breast cancer: A systematic review.

e23194 Background: Financial toxicity (FT), the detrimental effect of treatment-related expenses on patient outcomes, is a significant issue related to breast cancer diagnosis and treatment. The rising incidence of breast cancer among young adults (YA) age ≤ 40 has amplified concerns over FT in this demographic. Despite this, the degree to which YA status impacts FT is unclear. This systematic review sought to clarify the association between age and FT as a first step in understanding how FT may affect age-based health disparities. Methods: This systematic review queried PubMed, Embase, Web of Science, Sociological Abstracts, PsychINFO, CINAHL, and EconLit for full-text English language articles published between 2010-2024 reporting FT using validated patient-reported outcome metrics among patients with stage I-III breast cancer. Given that FT is a multidimensional construct, studies that assessed cancer-related costs alone without consideration for financial hardship, distress, or anxiety were excluded. As chemotherapy, a primary driver of cancer-related costs, is not routinely indicated for stage 0 disease, studies incorporating these patients were excluded. Two independent reviewers screened and extracted data between June-September 2024. Variables of interest included age and treatment-related adverse events. Quality was assessed using National Heart, Lung, and Blood Institute assessment tools. Results: Of 4,023 articles screened, 66 were included for full text review. Sixty-four were further excluded for including in situ or metastatic disease, multiple cancer subtypes, or if FT was assessed as a parameter of a larger scale without published precedent for stand-alone use. While no studies compared FT among YA versus non-YA women, the two remaining studies demonstrated that younger age was associated with worse FT. One of these compared those ≥65 to < 65 years old using the COST scale and the other considered age as a continuous variable and assessed FT using The Psychological Sense of Economic Hardship Scale. The latter also found that symptoms of breast cancer or its treatment were associated with greater FT after adjusting for age. Conclusions: In this systematic review, no study identified the multidimensional domain of FT as a primary outcome among YA versus non-YA women with non-metastatic invasive breast cancer. Although limited, two studies did show younger age to be associated with greater FT. Inconsistencies in age classification, use of validated outcome metrics, and criteria for FT limit our current understanding of how FT impacts YA with breast cancer. Further investigations exploring age as a social determinant of health are needed to support policy efforts that prevent sub-optimal outcomes for younger patients, including deviations from standard treatment related to affordability of care.