Parathyroid carcinoma occurred in two glands in multiple endocrine neoplasia 1: a report on a rare case.

Primary hyperparathyroidism is the most common hormonal manifestation associated with multiple endocrine neoplasia 1 (MEN1). It is generally caused by parathyroid hyperplasia, and parathyroid carcinoma is rare. Here, we report a case of MEN1 with parathyroid carcinoma in two parathyroid glands causing primary hyperparathyroidism. A 40-year-old man with primary hyperparathyroidism due to MEN1 underwent a total parathyroidectomy. His corrected calcium and intact PTH (i-PTH) serum levels were 10.8 mg/dL and 203 pg/mL, respectively. Although three glands were successfully removed, the left upper parathyroid gland could not be detected. Since the right lower parathyroid lesion had invaded into the thyroid, right lobectomy was performed. A portion of the left lower parathyroid tissue was transplanted into his forearm. The histological findings of the left lower and the right upper parathyroid glands were consistent with hyperplasia while that of the right lower parathyroid gland was parathyroid carcinoma. Since the post-surgical i-PTH levels remained high, the intrathyroidal lesion of the left lobe, which was initally diagnosed as an adenomatous nodule, was suspected to contain parathyroid tumor. A fine needle aspiration of the tumor revealed a high concentration of i-PTH. One week after the first surgery, a left thyroid lobectomy was performed. The pathological diagnosis of the tumor was parathyroid carcinoma. After the surgery, calcium and i-PTH levels were normal. Although it is rare, parathyroid carcinoma should be considered as a cause of hyperparathyroidism in MEN1 patients. Since it is difficult to diagnose parathyroid carcinoma before surgery, intraoperative findings are important for the appropriate treatment.

Impact of "Tailored" Parathyroidectomy for Treatment of Primary Hyperparathyroidism in Patients with Multiple Endocrine Neoplasia Type 1.

BACKGROUND: Whether total parathyroidectomy (TPTX) or subtotal parathyroidectomy (SPTX) should be performed for primary hyperparathyroidism (PHPT) in patients with multiple endocrine neoplasia type 1 (MEN1) is controversial. At our institution, the parathyroidectomy strategy is based on the number of enlarged intraoperative parathyroid glands. We retrospectively analyzed our parathyroidectomy procedures. METHODS: Data of PHPT treatment in patients with MEN1 who underwent parathyroidectomy from 1982 to 2012 at our department were retrospectively collected. The data were grouped according to the surgical procedure: TPTX, SPTX, and less than SPTX (LPTX). TPTX or SPTX was selected based on the preoperative examination findings and number of enlarged intraoperative parathyroid glands. The outcomes were the disease-free survival (DFS) rate and postoperative calcium replacement rate based on Kaplan-Meier analysis for each type of surgical procedure. RESULTS: Forty-five patients were analyzed. The overall 5- and 10-year DFS was 91.7 and 55.8%, respectively. The 5- and 10-year DFS in each subgroup was 100.0 and 85.7% in the TPTX group, 89.4 and 57.3% in the SPTX group, and 91.6 and 57.3% in the LPTX group, respectively. The postoperative calcium replacement rate at 1 and 12 months was 91.7 and 58.3% in the TPTX group, 21.1 and 7.0% in the SPTX group, and 30.0 and 0.0% in the LPTX group, respectively. CONCLUSIONS: Although LPTX was not satisfactory as a standard procedure, both SPTX and TPTX are effective treatment methods for PHPT in patients with MEN1. The parathyroidectomy strategy should be based on intraoperative evaluation of the parathyroid glands.