Parathyroid Adenomas with Pronounced Lymphocytic Infiltration: No Evidence of Autoimmune Pathogenesis

Abstract

Pronounced lymphocytic infiltration in parathyroid adenoma is rare, with only six previously reported cases in the literature. The aims of this study are to review the features and investigate the pathogenesis of this rare entity. Two solitary parathyroid adenomas having this feature were reported, and the clinicopathologic features of all the documented cases were reviewed. The nature of the lymphoid infiltrate and the presence of Epstein-Barr virus (EBV) were analyzed to unveil the pathogenesis of this infiltrate. One adenoma was found in a 70-yr-old woman with primary hyperparathyroidism and valvular heart disease. The other was an autopsy finding in a 48-yr-old man who had presented with hypercalcemic crisis. The lymphoid cell population within the tumors was composed of B cells and different subsets of T cells. EBV was not detected in the infiltrates. The lymphocytic infiltrate in parathyroid adenoma is an unusual histologic entity. Its presence is unlikely to imply an autoimmune disorder. We hypothesize that the lesion may be a result of local tissue response to parathyroid adenoma.

Functional and genetic studies of isolated cells from parathyroid tumors reveal the complex pathogenesis of parathyroid neoplasia

“…These findings support the hypothesis that the adaptive immune response influences the behavior of human tumors. However, lymphocytic infiltration in parathyroid adenoma is rarely reported (27), which suggests that our current findings may represent a newly recognized histologic feature. Because we found lymphocytes in both normal and adenomatous parathyroid glands, the role of these T cells is still unclear.…”

Parathyroid Adenoma with Prominent Lymphocytic Infiltrate

“…Its presence is not likely to imply an autoimmune disorder. The main hypothesis is that the lesion may be a result of local tissue response [2]. Another study suggested that the histological picture is consistent with an autoimmune process directed against the adenomas, indicating that this reaction had, in part, been successful in reducing the abnormal cell population [3].…”

Parathyroid Chief Cell Adenoma Associated with Massive Chronic Parathyroiditis in a Woman with Hyperparathyroidism

“…In addition, one of the patients had breast cancer and one had nodular goiter. Lam et al [8] examined one surgery-obtained parathyroid adenoma and one autopsy-obtained parathyroid adenoma and noted pronounced lymphocytic infiltration within the tumors. These authors claimed that the inflammation might have been due to local tissue response to the parathyroid adenoma.…”