Lee KM from Korea shared an interesting case in J Clin Ultrasound. The patient was a 59-year-old female with typical symptoms of hyperparathyroidism, in addition to imaging findings of right adrenal gland occupancy and two pituitary microadenomas, so there was no doubt that this patient was a type 1 multiple endocrine neoplasm. Curiously, (99m) Tc-MIBI revealed increased focal uptake of flat water in the right cervical thyroid, but ultrasound did not reveal parathyroid tumors, only multiple thyroid nodules. The major thyroid nodule then underwent a puncture biopsy, which suggested follicular lesions. Postoperative pathology revealed intra-thyroidal parathyroid carcinoma. This case demonstrates that fine needle aspiration is difficult to diagnose parathyroid cancer.