Left parathyroid carcinoma with secondary hyperparathyroidism: a case report.

backgroundParathyroid carcinoma is a rare disease with a frequency of 0.005% of all malignancies [1, 2]. Various aspects of its pathogenesis, diagnosis, and treatment remain poorly understood. Furthermore, cases with secondary hyperparathyroidism are fewer. In this case report, we describe a case of left parathyroid carcinoma with secondary hyperparathyroidism. CASE PRESENTATION: The patient was a 54-year-old woman who had been on hemodialysis since the age of 40 years. At 53 years of age, her calcium levels were high, and she was diagnosed with drug-resistant secondary hyperparathyroidism and was referred to our hospital for surgical treatment. Blood tests revealed calcium levels of 11.4 mg/dL and intact parathyroid hormone (PTH) levels of 1007 pg/mL. Neck ultrasonography revealed a 22-mm large round hypoechoic mass, partially indistinct margins, and D/W ratio > 1 at the left thyroid lobe. Computed tomography scans revealed a 20-mm nodule at the left thyroid lobe. No enlarged lymph nodes or distant metastases were noted.

conclusionsWe report a case of left parathyroid carcinoma associated with secondary hyperparathyroidism. Concomitant secondary hyperparathyroidism may cause mild hypercalcemia compared to parathyroid carcinoma alone due to the added modification of dialysis. Although our patient also presented with mild hypercalcemia, a D/W ratio > 1 on preoperative echocardiography and presence of recurrent nerve palsy on laryngoscopy led to the suspicion and treatment of parathyroid carcinoma preoperatively.