Metastatic breast cancer in elderly women: A retrospective cohort study in Morocco.

e13073 Background: Breast cancer (BC) stands as the predominant malignancy among women worldwide, presenting a significant global public health problem. In Morocco, it is the leading cause of cancer-related mortality in females. However, there exists a limited understanding of outcomes and treatment patterns for elderly patients with metastatic breast cancer (MBC) in our context. Methods: We conducted a retrospective cohort study at the Department of Medical Oncology, Hassan II University Hospital of Fez, focusing on 92 female patients aged 65 years or older diagnosed with MBC, between January 2012 and December 2016. The primary objectives were to estimate overall survival (OS) and progression-free survival (PFS), describe treatment patterns, and characterize the clinicopathological, and prognostic aspects of MBC in elderly women in Morocco. Results: The cohort’s median age was 70.88 (range, 65-88years) with 45.6% of patients aged of 65 to 69 years, 34.8% between 70 to 74 years old, and 19.6% over 75. Most patients (77.2%) had an Eastern Cooperative Oncology Group (ECOG) score of 0 to 1, and only 33.7% had comorbidities. De novo stage IV constituted 59.8% of all cases. Metastatic recurrences represent 40.2% with 16.2% having recurrence within 12 months, and 83.8% having a recurrence interval exceeding 12 months. The median time to recurrence was 45.5 months. Invasive ductal carcinoma (IDC) was the predominant histological type (81.1%), with SBR grade II (51%) and grade III (21.7%). Metastases were observed in pleuropulmonary (78.3%), bone (56.5%), lymph nodes (33.7%) and liver (30.4%). With 71.7% having metastases in fewer than three sites, while 28.3% had metastases in three or more sites. Molecular profiling showed Luminal A (38%) and Luminal B (26.1%) subtypes as the most prevalent, followed by triple-negative (17.4%) and HER2+ (15.2%). Treatment modalities included chemotherapy (50%), hormone therapy (15.2%) or a combination of the two (17.4%), and anti-HER2 targeted (14.1%). Median OS was 37 months (95% CI: 16.86 - 57.13 months), and median PFS was 33.16 ± 4.1 months. Anti-HER2 therapy showed a significant association with survival (p = 0,05). Conclusions: This study highlights the characteristics, survival, and treatment modalities of elderly patients with MBC in Morocco. Despite the predominance of luminal BC an intriguing observation was the frequent use of chemotherapy as first line modality.