Is There a Regular Pattern in the Recovery of Parathyroid Function After Thyroid Cancer Surgery?

PURPOSE: To investigate whether there is a pattern of recovery of parathyroid function after thyroid cancer surgery. PATIENTS AND METHODS: The study included 183 patients with papillary thyroid cancer (PTC) who underwent “total thyroidectomy (TT)” plus “unilateral central lymph node dissection (UCLND)” or “bilateral central lymph node dissection (BCLND)”. The intact parathyroid hormone (iPTH) and serum calcium (sCa) were analyzed several times within 1 month after surgery to explore the recovery pattern of parathyroid gland function. Then, these 183 cases were divided into group A (97 cases) with UCLND and group B (86 cases) with BCLND to analyze whether the impairment and recovery of parathyroid function were different between the two subgroups. RESULTS: Postoperative hypoparathyroidism was seen in 115 out of 183 cases. iPTH values decreased significantly on postoperative day (POD) 1 compared with preoperative values, dropped to the lowest point on POD 3, showed an increasing trend on POD 5 and 14, and increased to 85.0% of preoperative values at POD30, whereas changes in sCa differ from changes in iPTH, which showed the lowest sCa value on POD1, and rebounded on the POD3 with the intervention of calcium supplementation, and continued to rise on the POD5 and POD14, and the sCa value reached 96.6% of the preoperative level at POD30. Subgroup analysis showed that temporary hypoparathyroidism was more pronounced in group B than in group A. SCa and iPTH levels in both subgroups showed the same trend of first decrease and then increase. CONCLUSION: The recovery of hypocalcemia and hypo-iPTHemia in the first month after thyroid cancer surgery shows a trend of decreasing and then increasing, and knowing the recovery of parathyroid function at different time points is of great value to surgeons and patients alike.