Which of the following helps in differentiation of follicular carcinoma from follicular adenoma of thyroid: (A) Huhle cell, (B) Lining of tall columnar and cuboidal cell, (C) Vascular invasion, (D) Increased mitoses
Answer is C. Ref Robbins 9/e p1094 Microscopically most follicular carcinomas are composed of uniform cells forming small follicles.follicular carcinomas may be grossly infiltrative or minimally invasive. The latter are sharply demarcated lesions on gross examination . This distinction requires extensive histologic sampling to exclude capsular or vascular invasion