MKI67 and differentiated thyroid carcinoma: For thyroid tumours, it has been shown that anaplastic tumours have higher Ki67 indices than well-differentiated thyroid tumours (Carr et al, 1993), and that Hürthle cell carcinomas of the thyroid have higher Ki67 indices than benign Hürthle cell adenomas (Erickson et al, 2000).