Fig. 2
A. Histopathological macroscopic findings. The thyroid gland was flat and atrophic although its area was wide. B.C.D. Histopathological microscopic findings. Diffuse hyperplasia of the thyroid gland and hyperplastic thyroid follicles with papillary infoldings was observed on histopathological image. Tall follicular cells with papillae lacked fibrovascular cores and peripheral scalloping was present (red arrow). On the other hand, a part of the thyroid area showed a dense lymphoplasmacytic infiltrate, accompanied by follicles containing germinal centers (red triangle). In addition, a destroyed pattern of lymphoid follicle was observed (black arrow)