Clinical characteristics and outcomes of patients operated for primary hyperparathyroidism at Tampere University Hospital in 2017–2018

Background and objective: Studies on the outcomes of parathyroid surgery are scarce. The aim was to report the outcomes and to study the association between pre- and peri-operative information with the outcomes of patients operated for primary hyperparathyroidism. Methods: This was a retrospective, descriptive study with unselected patients treated surgically for primary hyperparathyroidism from a catchment population of 704,500 in Finland. Data were acquired from the electronic hospital registers based on parathyroid surgery procedure codes between 1 January 2017 and 31 December 2018. Preoperative data, surgical data, preoperative and postoperative laboratory values, histopathological findings, and postoperative clinical data were recorded. Results: During the 2-year study period, 149 patients with primary hyperparathyroidism were treated surgically with a 97% remission rate. Surgical complications included postoperative bleeding in two patients (1%) and vocal cord paralysis in one patient (0.6%). No postoperative infections were reported. Three patients (2%) developed postoperative hypoparathyroidism necessitating the use of alfacalcidol more than 1 month after surgery. Ionized calcium measured 0–1 days after surgery was not statistically significantly associated with remission or postoperative hypoparathyroidism. Serum parathyroid hormone (PTH) assessed 0–1 days postoperatively was associated with persistent disease, but not with postoperative hypoparathyroidism. The histopathological diagnosis was adenoma or hyperplasia in 112 patients (75%), atypical adenoma in 28 patients (19%), and carcinoma in five patients (3%). Patients with parathyroid carcinoma had higher preoperative ionized calcium and PTH values than those with adenoma or hyperplasia. Conclusions: Most patients who were operated due to primary hyperparathyroidism achieved normocalcemia after surgery, and the frequency of complications was low. Ionized calcium taken 0–1 days after surgery was not associated with remission of hyperparathyroidism or postoperative hypoparathyroidism. High postoperative serum PTH predicted persistent disease.