MKI67 and triple-negative breast carcinoma: Furthermore, in a study of 1951 cases of primary breast cancer at a hospital in Pakistan in 2019, triple-negative breast cancer was found to have the highest number of cases with high Ki-67 expression (>45%) while the Luminal A subtype had the lowest number of cases, Furthermore, metaplastic breast cancer was determined to possess a higher Ki-67 level compared to ductal carcinoma [8].