Background: Breast cancer (BC) is the most common type of cancer among Iranian women. BC treatment costs a lot and many families cannot afford to pay it. This study was conducted with the aim of determining the out-of-pocket (OOP) health expenditure and factors affecting it in BC patients in Shahid Jalil Hospital affiliated to Yasuj University of Medical Sciences.

Methods: This study was conducted in a cross-sectional descriptive-analytical way. Based on the inclusion criteria, the health expenditure of 82 patients with BC were collected. The data were collected using the discharge costs of patients in Shahid Jalil Hospital affiliated to Yasuj University of Medical Sciences, inpatient and outpatient data of Iran Health Insurance Organization and declared costs by patients in 2022. The study data were analyzed using descriptive statistics methods including frequency, percentage, mean and standard deviation and stepwise linear regression to investigate the effect of variables on the amount of OOP health expenditure in SPSS 21 software.

Results: The share of OOP expenses by BC patients was 32.89% of the total direct medical expenses. 47.18% of OOP costs included drug costs, 16.19% laboratory costs, 11.74% imaging costs, 11.20% visit costs, 8.40% hospitalization costs, 2.84% doctor’s services, and 2.45% related to physical therapy. Factors such as age, place of residence, occupation, education, and household income were among the factors that had a significant effect on OOP payments (p<0.05). Marital status, Housing situation, and social coverage had no significant effect on patients' OOP payments (p>0.05).

Conclusion: BC patients incur a lot of expenses, and about 32.89% of these expenses are OOP payments. Therefore, it is necessary for the insurance organizations to increase their paid share, and on the other hand, there is a need for more support from the government for BC patients in the provision of medicine and medical items needed more than ever.

Key words: Breast Cancer, Out-Of-Pocket, Health Expenditure, Factors Affecting