Molecular subtypes of breast cancer in Libyan women and their clinicopathological associations: A retrospective observational study from eastern Libya

Breast cancer (BC) is the most commonly diagnosed cancer among women globally, with significant regional variations in its molecular subtypes, clinical presentation, and management. Despite advancements in oncology, limited data exist on the molecular and clinical characteristics of BC in Libya. This study aims to analyze the prevalence of molecular subtypes, clinicopathological features, and treatment patterns among Libyan women with BC at Tobruk Medical Center. This retrospective observational study included BC patients diagnosed between January 2019 and December 2020 at Tobruk Medical Center. Demographic, clinical, pathological, and treatment-related data were extracted from medical records. Molecular subtyping was based on immunohistochemical assessment of estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2 (HER2), and Ki-67. Statistical analyses were performed using SPSS version 28 (IBM Corp., Armonk). Among 115 patients analyzed, the median age at diagnosis was 46 years. Invasive ductal carcinoma accounted for 89.6% of cases, with grade II tumors being the most common (69.6%). Luminal B was the predominant molecular subtype (67.8%), followed by luminal A (14.8%), HER2-enriched (10.4%), and triple-negative BC (7.0%). Advanced-stage diagnoses (stage III and IV) were observed in 57.4% of cases. Hormone receptor positivity was detected in 82.6%, and HER2 positivity in 25.2% of cases. This study highlights the high prevalence of advanced-stage BC and the predominance of the aggressive luminal B subtype in Libya. Targeted early detection programs and improved treatment access are urgently needed to address these challenges.