Correlations between parathyroid hormone level, adenoma size, and serum calcium level in patients with primary hyperparathyroidism

Abstract

Aim: The main goal of this study is to determine the association of preoperative parathyroid hormone (PTH) levels with parathyroid gland adenoma sizes and serum calcium levels in patients with primary hyperparathyroidism caused by single-gland adenoma. Methods: We included all patients with single parathyroid gland adenoma who were admitted to and underwent parathyroidectomy at Security Forces Hospital in Riyadh during a period of 10 years from January 1, 2000 to October 30, 2011. PTH level and serum corrected calcium were recorded 1 day before surgery. Adenoma size was recorded from pathology reports for all patients. Results: In 35 cases of parathyroid adenoma including 12 males (34.3%) and 23 females (65.7%) with an average age of 48.94 years (±13.52), the average PTH level 1 day preoperatively was 769.94 pg/mL (±793.27), the average largest dimension (LD) of parathyroid adenoma was 2.18 cm (±1.38), and the average calcium level 1 day preoperatively was 2.71 mmol/L (±0.3). The mean PTH level in males was 1098.5 pg/mL compared to 598.5 pg/mL in females (P = 0.068), mean LD of parathyroid adenoma in males was 2.34 cm versus 2.09 cm in females (P = 0.72), and mean calcium level in males was 2.70 mmol/L compared to 2.72 mmol/L in females (P = 0.46). A positive correlation was found between PTH level and adenoma size, with a correlation coefficient of 0.29 (P = 0.095). The correlation between PTH level and calcium level was negative, with a correlation coefficient of −0.033 (P = 0.85). Negative correlation was also found between adenoma size and calcium level, with a correlation coefficient of −0.033 (P = 0.85). Conclusion: Based on the findings of this study, preoperative PTH level or serum calcium level cannot be used to predict adenoma size. Further prospective studies with larger sample sizes are recommended.