Synchronous intrathyroidal parathyroid carcinoma and thyroid carcinoma: case report and review of the literature

Abstract

Background Parathyroid carcinoma is a rare endocrine malignancy, rarer when synchronous with a non medullary well differentiated thyroid carcinoma. Parathyroid carcinoma accounts of 0.005% of all malignant tumors and it is responsible for less than 1% of primary hyperparathyroidism. The intrathyroidal localization of a parathyroid gland is not frequent with a reported prevalence of 0.2%. Carcinoma of parathyroids with intrathyroidal localization represents an even rarer finding, reported in only 16 cases described in literature. The rare constellation of synchronous parathyroid and thyroid carcinomas has prompted us to report our experience and perform literature review. Case presentation We herein report a case of a 63-years-old man with multinodular goiter and biochemical diagnosis of hyperparathyroidism. Total thyroidectomy with radio-guide technique using gamma probe after intraoperative sesta-MIBI administration and intraoperative PTH level was performed. The high radiation levels in the posterior thyroid lobe discovered an intrathyroidal parathyroid. Microscopic examination revealed a parathyroid main cell carcinoma at the posterior thyroidal left basal lobe, a classic papillary carcinoma at the same lobe and follicular variant of papillary carcinoma at the thyroidal right lobe. To the best of our knowledge, this is the first case documenting a synchronous multicentric non medullary thyroid carcinomas and intrathyroidal parathyroid carcinoma. Conclusions Our experience was reported and literature review underlining challenging difficulties in diagnostic workup and surgical management was carried out.

Synchronous parathyroid carcinoma and papillary thyroid carcinoma

“…Synchronous parathyroid and nonmedullary thyroid carcinomas are extremely rare with only 15 previous cases reported in literature, 1,5–7,13–23 and no correlation, up to date, has been discovered between these entities 24 . Twelve patients (84%) were females with relatively young age (mean age of 56 years).…”

“…15 The lowest serum calcium level reported in the literature with parathyroid carcinoma has been 12.2 mg/dl, and the lowest reported PTH level associated with parathyroid carcinoma has been 159 pg/ml in conjunction with a serum calcium level of 13.3 mg/dl. 1 Most of the reported cases with active parathyroid tumor had severe hypercalcemia and elevated PTH levels to up 100 times normal levels. The average size of the parathyroid carcinoma was 3.2 cm (maximum >5 cm) with two cases of concomitant hyperplasia or parathyroid adenoma.…”

“…Although parathyroid carcinoma is not a usual cause of primary hyperparathyroidism, 1,2,9 its incidence is increasing due to increased incidence of diagnosed primary hyperparathyroidism 10 . Many presenting features of parathyroid hormone‐dependent hypercalcemia that should suggest the etiology of parathyroid carcinoma are shown in Table 2 11 .…”

“…Parathyroid carcinoma is a rare endocrine malignancy, rarer when synchronous with a nonmedullary well‐differentiated thyroid carcinoma 1 . Parathyroid carcinoma (PC) accounts of 0.005% of all malignant tumors, and it is responsible for less than 1% of primary hyperparathyroidism 2,3 …”

“…Parathyroid carcinoma is a rare endocrine malignancy, rarer when synchronous with a nonmedullary well-differentiated thyroid carcinoma. 1 Parathyroid carcinoma (PC) accounts of 0.005% of all malignant tumors, and it is responsible for less than 1% of primary hyperparathyroidism. 2,3 The initial manifestation of parathyroid carcinoma is usually quite acute, and the serum calcium and parathyroid hormone (PTH) levels are often higher than with parathyroid adenoma.…”