The evolution of financial toxicity in patients with lung cancer.

e19406 Background: Financial toxicity (FT), or the cost-related side effect of cancer therapy, has been linked to poor clinical outcomes, greater symptom burden, and worse quality of life. While the repercussions of FT have been thoroughly explored, the longitudinal patient relationship with FT in the initial course of therapy is unknown. Methods: Patients with stage II – IV lung cancer were recruited in a prospective longitudinal non-interventional study between July 2018 and January 2020. FT was measured via the COST score, a validated questionnaire for benchmarking FT, at a) the time of cancer diagnosis and then later at b) 6-month follow up (6MFU). In this model, a lower COST score indicates increased financial hardship. Completed 6MFU data was compared to corresponding baseline data for each patient. Linear regression analysis was used to compare patient characteristics with baseline COST (COSTbase) and 6-month COST (COST6M) scores. Results: At the time of analysis, 209 patients were screened and 194 (95.1%) patients agreed to participate and complete the baseline survey. Subsequently, 93 patients completed the 6MFU survey, 32 patients had died, and 7 patients were lost to follow up. The remaining 62 patients have not met the study end point to date. Of the 93 patients that completed the 6MFU and baseline survey, the median age was 65 (range 35-89), 50.5% were male, and 76.3% were Caucasian. Over the first six months of therapy 36.5% overestimated OOP expenses by > $1000 and 22.5% reported a decrease in total monetary savings, but only 4.3% of patients made decisions about health care based on cost of care. FT was present at both time points but was worse at diagnosis than at 6MFU (median COSTbase 25 [range 1-44] vs. median COST6M 27 [range 0-44]; p = 0.04). Linear regression correlated risk factors with FT at baseline ( < 1 month monetary savings, employed but on sick leave, and inability to afford basic necessities; all p < 0.001) that were different from risk factors at 6MFU (paying much more than expected OOP and sacrificing spending to meet medical costs; p < 0.001). There was no significant difference between estimated OOP costs at baseline (median $2550 [range $0 - $500,000]) and actual OOP costs (median $2496 [range $0 – 25,900]; p = 0.25). Conclusions: FT toxicity is pervasive at both diagnosis and at 6-month follow up, however, the magnitude of toxicity changes with time. Few patients are willing to sacrifice medical care regardless of the cost. Risk factors for FT evolve, suggesting that different groups may benefit from financial intervention at diagnosis versus 6MFU.