Advancing Education, Research, and Quality of Care for the Head and Neck oncology patient.
Background: Previous research indicates that the odds of permanent hypoparathyroidism decrease with increasing surgeon total thyroidectomy experience, identifying 25 thyroidectomies per year as a key threshold for reducing these odds. However, parathyroid hormone levels alone may not represent the most clinically relevant outcome due to postoperative fluctuations and factors such as vitamin D status and outpatient calcium supplementation. Moreover, prior studies that examine annual thyroidectomy volume may fail to capture the early learning curve. To address these limitations, we examined patients' need for permanent postoperative calcium supplementation after total thyroidectomy and defined surgeon experience as the cumulative number of total thyroidectomies for each surgeon up to the date of each patient's surgery. This approach aims to determine the number of total thyroidectomies needed for clinically meaningful improvements and to better capture the impact of early career experience after fellowship.
Methods: All patients who underwent total thyroidectomy between January 2010 and June 2024 at our institution were identified using associated CPT codes (38742, 60240, 60252, 60271). The main outcome was permanent oral calcium supplementation (present >365 days after surgery). Surgeon experience, performing surgeon, surgical indication, and patient demographics and comorbidities were collected. Generalized Additive Models (GAM) were fitted to examine the association of surgeon experience with rates of permanent calcium supplementation. The optimal surgeon experience was defined as the point at which the GAM curve intersected with y=0, where the relative odds of requiring permanent calcium supplementation shift from positive to negative. A subset of two surgeons who began their careers at our institution was analyzed to assess the impact of early career experience. A quadratic term for surgeon experience was included to test the hypothesis that early-career surgeons would exhibit a steeper slope in the relationship between surgeon experience and odds of calcium supplementation compared to the all-surgeons dataset.
Results: A total of 2,914 patients and 13 surgeons (513 patients and 2 surgeons in the subset) were identified. The GAM plots demonstrated that increasing surgeon experience significantly reduced the odds of permanent calcium supplementation, with relative odds approaching zero after 1,500 cumulative thyroidectomies. The quadratic term for surgeon experience was not statistically significant in the all-surgeons dataset (p=0.625) but was significant in the subset (p=0.001). Taken together, these data suggest that the risk of permanent hypocalcemia decreases more rapidly with experience in early career among fellowship-trained thyroid surgeons.
Conclusion: Our findings demonstrate that 1,500 cumulative total thyroidectomies mark the experience level at which the relative odds of requiring permanent calcium supplementation approach zero. Although our early career surgeon data are limited, fellowship-trained thyroid surgeons appear to have a rapid decrease in permanent hypocalcemia rates early in their career. To our knowledge, this is the first investigation of early-career surgeon experience on the probability of permanent calcium supplementation after total thyroidectomy and could be used to inform future training policies.