MKI67 and T-cell and NK-cell neoplasm: In a study by Yoshida et al (not included in Table 1  because it did not include Ki-67 LI), primary thyroid T-cell lymphoma (PTTL) also showed an indolent clinical course.[8] The authors suggested that the PTTL of Th1-cell origin might be a T-cell malignancy corresponding to a MALToma and that PTTL is a distinct T-cell neoplasm among PTCL-NOS because autoimmune thyroiditis is associated with development with MALToma by mediation of Th1-cells.