Case Presentation
A 65-year-old woman was referred to our hospital because of
hypercalcemia. She had undergone total thyroidectomy for thyroid cancer
30 years prior along with left-sided parathyroid auto-transplantation in
her neck, without any family history of endocrine diseases. Physical
examination showed a surgical scar on the left side of her neck
(Fig. 1 ). Her serum calcium, phosphate, and intact parathyroid
hormone levels were 11.3 mg/dL, 3.4 mg/dL, and 170 pg/mL, respectively.
Tc-99m-MIBI demonstrated increased uptake in the autograft in the left
supraclavicular region (Fig. 2 ). Based on these findings,
primary hyperparathyroidism due to the autografted parathyroid gland was
strongly suspected. Although parathyroid tissue auto-transplantation is
useful for preventing hypoparathyroidism during thyroidectomy,
hyperparathyroidism may occur due to proliferation of the transplanted
parathyroid tissue (1, 2). This case suggests that long-term regular
monitoring of serum calcium levels may be necessary after parathyroid
auto-transplantation even in patients without multiple endocrine
neoplasia.