Immunohistochemical Profile of Breast Cancer: A Retrospective Study in the Democratic Republic of Congo

Background: The management of breast cancer increasingly requires molecular classification based on immunohistochemistry. As breast cancer is a heterogeneous disease characterized by the accumulation of multiple molecular alterations that give each tumour its own phenotype and evolutionary potential, immunohistochemistry, as a complementary technique to morphological examination, determines the status of hormone receptors and on protein in tumour cells, which are predictive and prognostic markers of breast cancer. This technique is often little used in the Democratic Republic of Congo (DRC), as this study shows. The under-use of this technique due to a lack of equipment and/or human skills explains the paucity of epidemiological data available to date. Objective: Determine the immunohistochemical profile of breast cancer. Methodology: This is a retrospective study carried out in the Anapath Department of the NGANDA Hospital from January 1, 2020 to December 31, 2022, i.e. a 3-year period. Result: A total of 736 patients were registered in the hospitalization register of the Oncology Department of CH NGANDA for the period corresponding to the present study. Breast cancer was diagnosed in 110 patients, representing 14.9% of all cases. The mean age of the patients was 58.4 ± 8.2 years, with extremes ranging from 30 to 76 years. Breast nodules were the most common reason for diagnosis in 56.3% of cases, with Luminal A dominating in 17.3%. Conclusion: Breast cancer is a major public health problem. Worldwide, it is the most frequently diagnosed cancer in women and the leading cause of cancer-related death in women. In the Democratic Republic of Congo, because of the delay in consulting our patients and the weakness of systematic screening, patients are seen at an advanced stage of the disease. Treatment is multidisciplinary, involving surgery, radiotherapy, chemotherapy (including targeted therapies) and hormone therapy. Patient awareness and screening campaigns will contribute to a considerable reduction in the delay in diagnosis and the morbidity and mortality associated with breast cancer.