Several hypotheses have been brought up to explain the development of parathyroid cysts: (i) vestigial origin and development from the third or the fourth branchial cleft cyst; (ii) coalescence of parathyroid acini; (iii) parathyroid development failure (degenerative cyst) [13] in which remaining parathyroid chief cells start secreting PTH, as seen in case 2 of this report [14, 15]; (iv) retention of secretion vesicles [6]; and finally (v) intra-adenoma hemorrhage with consecutive liquefaction of the hematoma. Here, PTH is linked to adenoma.