Although established, oncogenic PIK3CA hotspot mutations are significantly more common in parathyroid carcinoma (approximately 10%) in comparison to parathyroid adenomas (1%; Fisher exact test, p = 0.0019), adenomas are roughly 100 to 200 times more common than carcinoma, decreasing the positive predictive value of PIK3CA mutational testing in unselected cases. Here, PIK3CA is linked to parathyroid gland adenoma.