Comparison between patients with hypocalcemia (n = 51) and normocalcemia (n = 125) on postoperative day 1 demonstrated that there were significant differences in male ratio (7.84% vs. 28.57%, p=0.004), PTH level reduction (86.19% vs. 53.01%, p < 0.001), tumor diameter (1.30 vs. 0.90 cm, p=0.028), and preoperative serum Ca levels (2.32 vs. 2.36 mmol/l, p=0.034; Table 2). Here, PTH is linked to Hypocalcemia.