MKI67 and mature T-cell and NK-cell non-Hodgkin lymphoma: To our knowledge, 22 cases of indolent PTCL with low Ki-67 LI have been reported in the literature, which are summarized in Table 1 .[2–6] These 22 cases included 11 men and 11 women (M: F = 1: 1) with an average age of 53.5 years (range: 15–82).