Background and purpose

Multigland disease represents a challenging group of patients with primary hyperparathyroidism. Additional lesions may be missed on imaging because they are not considered or are too small to be seen. The aim of this is study was to identify 4D-CT imaging and biochemical predictors of multigland disease.

Materials and methods

This was a retrospective study of 155 patients who underwent 4D-CT and successful surgery with a biochemical cure that compared patients with multigland and single-gland disease. Variables studied included the size of the largest lesion on 4D-CT, the number of lesions prospectively identified on 4D-CT, serum calcium levels, serum parathyroid hormone levels, and the Wisconsin Index (the product of serum calcium and parathyroid hormone levels). Imaging findings and the Wisconsin Index were used to calculate a composite multigland disease scoring system. We evaluated the predictive value of individual variables and the scoring system for multigland disease.

Results

Thirty-six patients with multigland disease were compared with 119 patients with single-gland disease. Patients with multigland disease had significantly lower Wisconsin Index scores, smaller lesion size, and a higher likelihood of having either multiple or zero lesions identified on 4D-CT (P ≤ .01). Size cutoff of <7 mm had 85% specificity for multigland disease, but including other variables in the composite multigland disease score improved the specificity. Scores of ≥4, ≥5, and 6 had specificities of 81%, 93%, and 98%, respectively.

Conclusions

The composite multigland disease scoring system based on 4D-CT imaging findings and biochemical data can identify patients with a high likelihood of multigland disease. Communicating the suspicion for multigland disease in the radiology report could influence surgical decision-making, particularly when considering re-exploration in a previously operated neck or initial limited neck exploration.

Background and purpose

Patients with multigland primary hyperparathyroidism are at higher risk for missed lesions on imaging and failed parathyroidectomy. The purpose of this study was to prospectively validate the ability of previously derived predictive score systems, the composite multigland disease score, and the multiphase multidetector contrast-enhanced CT (4D-CT) composite multigland disease score, to identify patients with a high likelihood of multigland disease.

Materials and methods

This was a prospective study of 71 patients with primary hyperparathyroidism who underwent 4D-CT and successful parathyroidectomy. The size and number of lesions identified on 4D-CT, serum calcium levels, and parathyroid hormone levels were collected. A composite multigland disease score was calculated from 4D-CT imaging findings and the Wisconsin Index (the product of the serum calcium and parathyroid hormone levels). A 4D-CT multigland disease score was obtained by using the CT data alone.

Results

Twenty-eight patients with multigland disease were compared with 43 patients with single-gland disease. Patients with multigland disease had a significantly smaller lesion size (P < .01) and a higher likelihood of having either ≥2 or 0 lesions identified on 4D-CT (P < .01). Composite multigland disease scores of ≥4, ≥5, and 6 had specificities of 72%, 86%, and 100% for multigland disease, respectively. 4D-CT multigland disease scores of ≥3 and 4 had specificities of 74% and 88%.

Conclusions

Predictive scoring systems based on 4D-CT data, with or without laboratory data, were able to identify a subgroup of patients with a high likelihood of multigland disease in a prospectively accrued population of patients with primary hyperparathyroidism. These scoring systems can aid in surgical planning.