Parathyroid adenoma is composed mainly of chief and oxyphil cells. In rare cases during histopathological examination there may be found lymphoid tissue within parathyroid adenoma in form of germinal centers. In the literature there are only 11 cases of such atypical parathyroid adenomas. Clinical significance of parathyroid infiltration with lymphoid tissue remains unknown. We present 12th in the world case of parathyroid adenoma with germinal centers described during histopathological examination of excised parathyroid gland.

53 year old woman underwent parathyroidectomy because of primary hyperparathyroidism. After obtaining unusual histopathological result we have searched pubmed database. Additional immunohistochemistry examination was performed on specimen.

We have found only 11 similar cases with lymphoid tissue infiltration within parathyroid adenoma in the worldwide literature. There are two patterns of such infiltrations described: one diffused and one focalized. Our patient fits in focalized pattern with organized germinal centers. Thorough patients history reevaluation rules out any history of family hereditary endocrine or autoimmune diseases. Patient did not have any sign of inflammatory process or autoimmune disease although not other specific blood test were performed.

Rarely histopathological image of excised parathyroid adenoma may be unlike routinely found pattern. Despite scarcity of representative group for drawing out statistically significant clinical conclusions similar patterns we believe that this finding does not change typical disease course and parathyroidectomy is definitive treatment.