Category: Calcium/Bone Disorders

Monitor: 27


Friday, Apr 26
12:30 PM – 1:00 PM

Objective :

A rare case of a parathyroid adenoma presenting with characteristics of a parathyroid carcinoma.
64-year-old Hispanic woman with past medical history of Hashimoto’s thyroiditis and nephrolithiasis who presents with symptoms of fatigue, generalized weakness, unintentional weight loss, polyuria and polydipsia.  Initial Calcium 13.9 mg/dl and PTH level 783 ng/DL and Creatinine levels 2.3mg/dl. Urinary Calcium levels: 380mg/24-hour. Sestamibi Scinthigraphy with persistent concentration throughout the left lobe in favor of a large left parathyroid adenoma. Thyroid sonogram showed left thyroid lobe nodule measuring 0.4 cm with left posterior neck lymphadenopathy.  On physical examination with left posterior neck adenopathy. Left parathyroidectomy was performed.  Preoperative calcium 14.2 mg/dl.  Intraoperative PTH level 1400 ng/dl and post resection a PTH 130 ng/dl confirming removal of the hyperactive gland. Intraoperative pathology report showed that the left parathyroid specimen resected was consistent with a parathyroid adenoma. After resection, patient presented with hypocalcemia secondary to hungry bone syndrome for which patient was treated with calcium supplements and calcitriol. 1 year later after left parathyroidectomy patient is asymptomatic, normocalcemic and PTH levels are within normal limits.

Methods : n/a

Results :


Discussion : The diagnosis of parathyroid carcinoma is typically dependent on the patient’s clinical presentation, laboratory studies, imaging, and lastly histopathology. Preoperative calcium levels greater than 14 mg/dL and parathyroid hormone levels >3 times the normal value are reasons for suspicion of parathyroid carcinoma. In this case, the patient presented with symptoms characteristic of parathyroid carcinoma, elevated serum calcium, elevated PTH level more than 10 times the normal range, elevated urinary calcium, impaired renal function and imaging presenting with a large left parathyroid adenoma suspicious for malignancy. Histopathological examination ultimately proved to be different from what it was expected to be ruling out malignancy and in favor of parathyroid adenoma as the final diagnosis.

Conclusion : Parathyroid carcinoma is a rare cause of primary hyperparathyroidism. It is difficult to distinguish from parathyroid adenoma based on preoperative evaluation. Awareness of the different presentations of a parathyroid adenoma is crucial for appropriate diagnoses, prompt management and patient orientation of this condition especially when its presentation is suspicious for malignancy.  Parathyroidectomy in these circumstances is the preferred method for diagnosis and treatment.


Karol Sanchez Marrero

Endocrinology fellow
San Juan City Hospital
Carolina, Puerto Rico

Karol Sanchez -Marrero is an endocrinology fellow currently completing her first year of endocrinology fellowship at San Juan City Hospital in San Juan, Puerto Rico. She completed her bachelor’s degree at University of South Florida in Tampa, FL and then completed her medical education at Ponce Health Sciences University in Ponce, PR in 2013. Her career journey continued in Damas Hospital in Ponce, Puerto Rico where she completed one year as a Transitional resident in 2015 and her Internal Medicine Residency in 2018. Dr. Karol Sanchez-Marrero is American Board Certified in Internal Medicine as of 2018.

Karol Sanchez

Endocrinology Fellow
San Juan City Hospital, San Juan, PR

Yanerys Agosto

Michelle Mangual