Large parathyroid tumors have an increased risk of atypia and carcinoma

BackgroundRisk for atypia and carcinoma in large parathyroid tumors is not known. Atypia and carcinoma were determined in small (<2 g) and large (≥2 g) tumors in patients undergoing parathyroidectomy for primary hyperparathyroidism.MethodsThe study was a retrospective analysis of a 5-year prospective database. Tumor weight, histopathology, age, gender, calcium, and parathyroid hormone levels were registered. Patients with 4-gland disease were not included.ResultsAmong 353 parathyroid tumors, 313 weighed <2 g and 40 weighed ≥2 g. There was no difference in age between groups. Patients with large tumors were more frequently men and had higher calcium and parathyroid hormone levels. Atypia was found in 4 of 313 (1.3%) and 7 of 40 (17.5%) small and large tumors, respectively (P < .05). Corresponding figures for carcinoma were 1 of 313 (.3%) and 2 of 40 (5.0%) (P < .05).ConclusionsLarge parathyroid tumors have increased risk for atypia and carcinoma. Even so, most large parathyroid tumors are benign.