# Optimizing breast cancer screening strategies for women with different BMI levels in Ghana: A simulation-based study on BMI-dependent tumor growth model

## TL;DR

The study finds that biennial mammography screening is optimal for all BMI levels in Ghana, but obese women may need more frequent screenings to detect breast cancer earlier.

## Contribution

The novelty lies in using a BMI-dependent tumor growth model and simulation to optimize breast cancer screening strategies for different BMI groups in Ghana.

## Key findings

- Biennial screening intervals yielded the best outcomes for all BMI levels compared to annual and triennial strategies.
- Obese individuals may benefit from shorter screening intervals (14-18 months) due to higher risk of interval-detected cancers.
- Women with normal body weight are more likely to be detected through screening rather than between screenings.

## Abstract

Breast cancer is a disease in which abnormal cells in the breast tissue grow out of control to form tumors and can spread to other parts of the body. While it can affect both men and women, it poses a greater risk to women, and it is a leading cause of cancer-related deaths worldwide. This study aimed to examine different mammography screening interval strategies using a body mass index (BMI)-dependent tumor growth model and a simulation approach. The goal was to identify the optimal screening strategy for various BMI levels by investigating the association between BMI and tumor growth rate, and further examine the relationship between BMI and screening outcomes, using a continuous growth model and Cox regression, respectively. Our results indicated that a biennial screening interval yielded the best outcomes for all BMI levels compared to annual and triennial strategies. Obese individuals may require higher screening sensitivity and are likely to benefit from shorter screening intervals than those with other body weights within the screening age range of 30 to 65 years. Additionally, obese individuals have a slightly higher risk of being diagnosed with interval-detected cancers rather than screen-detected cancers. In contrast, women with a normal body weight have a greater chance of being detected through screening rather than at intervals. These findings suggest that breast cancers may become symptomatic more quickly in obese individuals than in those with lower body weights. Consequently, the standard two-year screening interval may not be optimal for this group, indicating that more frequent screenings (14-18 months) could be necessary. This underscores the potential impact of improved screening practices to enhance the treatment and management of breast cancer.

Breast cancer, a disease that affects both women and men, is a significant global health concern. It is a leading cause of cancer-related deaths worldwide, with women facing a significantly higher risk. In 2020, it accounted for nearly one in eight cancer cases globally, making it the most concerning type of cancer for women. The year saw approximately 2.3 million new cases of breast cancer and around 685,000 deaths. By 2040, these numbers are estimated to rise to about 3 million new cases and 1 million deaths, underscoring the urgent need for effective screening strategies. In this study, we focused on incorporating body mass index into the tumor growth sub-model of the continuous growth model, and used a simulation approach to evaluate different strategies for mammography screening intervals and further examine BMI category association with screening outcomes. Our results showed that biennial screening is the most beneficial approach for all BMI levels, surpassing annual and triennial strategies. Furthermore, it was found that obese individuals, due to their increased need for screening sensitivity, may benefit from more frequent screenings than those with other body weights within the 30 to 65-year screening age range. It is important to note that obese individuals have a slightly higher risk of being diagnosed with interval-detected cancers rather than screen-detected cancers. In contrast, women with normal body weight are more frequently identified during screenings than between screenings. These findings suggest that breast cancers may become symptomatic more quickly in obese individuals than in those with lower body weights, indicating the necessity for more frequent screenings (14-18 months). This underscores the importance of the research findings and their potential implication for screening policies.