In oncogenesis, cell proliferation is one of the most essential biological processes and may therefore be a strong predictive and prognostic marker.2 Ki‐67 is a nuclear marker that is present in all phases of the cell cycle but absent in resting cells (G0 phase).3 Therefore, Ki‐67 is an ideal marker to quantify the relative amount of proliferative neoplastic cells within tumour tissue, defined as the Ki‐67 proliferation index (Ki‐67 PI). The gene discussed is MKI67; the disease is neoplasm.