Parathyroid carcinoma in multiple endocrine neoplasm type 1 syndrome: case report and systematic literature review

The aim of this report was to illustrate a case of parathyroid carcinoma (PC) in a patient with multiple endocrine neoplasia type 1 (MEN1) along with a comprehensive literature review. A 61-year-old man presented with 9-cm PC causing primary hyperparathyroidism (PHPT). His pre-operative corrected calcium and intact PTH serum levels were 2.92 mmol/L and 391.7 pg/mL, respectively. The neoplastic gland was removed in bloc with thyroid and central compartment lymph nodes. A literature review was run by searching PubMed MEDLINE from 1977 to 2018 for studies of all types, in the English language only, using the terms "Parathyroid, carcinoma, Multiple endocrine neoplasia, type 1, (MEN1)." Pathology confirmed PC. Post-operative calcium and PTH levels were normal. A diagnosis of MEN1 was established post-operatively. Seventeen cases of PC in patients with MEN1 have been reported in the literature. 59% of patients were men, and median age at diagnosis was 50 years, with median serum PTH of 379 pg/mL and median serum calcium level of 3.2 mmol/L. The occurrence of PC in the context of MEN1 is extremely rare. Diagnosis and treatment may represent a challenge, so opportune identification or suspicion of malignancy and adoption of correct surgical approach may offer affected patients the best outcome.