Characterizing breast cancer in Myanmar: Insights from receptor status and tumor staging

Abstract

Breast cancer is a significant global health challenge, with regional variations in its clinical and molecular characteristics. Understanding the interplay between tumor features and molecular subtypes in Myanmar is crucial for improving local breast cancer control strategies. This study investigates the relationship between tumor subtypes and tumor, node, and metastasis staging in a cohort of 184 biopsy- confirmed breast cancer patients diagnosed between January 2022 and December 2023. The mean age at diagnosis was 53 years, with 12% patients under 40. T2 was the most prevalent tumor stage, whereas N0 was the most common nodal status. M1 was identified in 22% of cases. Triple-negative breast cancer (TNBC) subtype showed significant associations with advanced T (p=0.002) and N (p=0.021) stages. In contrast, estrogen receptor-and progesterone receptor-positive tumors were more likely to be diagnosed at earlier stages (p<0.0001 and p=0.006, respectively). No statistically significant relationship was observed between receptor status and M stage or between human epidermal growth factor receptor 2 (HER2) status and component of tumor staging. These findings highlight the aggressive nature of TNBC and the more indolent course of hormone receptor-positive cancers within the studied population. The absence of a correlation between HER2 positivity and staging challenges existing global patterns and suggests population-specific dynamics that warrant further investigation. Overall, the study underscores the urgent need for improved early detection strategies and targeted therapies in Myanmar, particularly for patients with TNBC and those at risk of advanced-stage presentation.

Keywords

Breast cancer / Myanmar / Receptor status / Tumor staging

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