Endocrine Abstracts

Introduction: Brown tumors are bone lesions that arise due to osteoclastic activity and may mimic a true neoplasm. We encountered an unusual case of hyperparathyroidism with multiple brown tumors that mimicked metastatic bone tumor due to false positive results on computed tomography (CT).

Case: 60 year old gentleman presented to the medicine out patient department with complains of fever, cough and right chest pain. Due to severe chest infection he was admitted, and CT scan was done. CT scan showed multiple lytic lesion in bilateral ribs with some areas of cortical breach suggestive of metastasis/multiple myeloma/enchondroma along with multiple calcifications in bilateral kidneys. With all the differentials in mind patient was evaluated. M Band was negative with high corrected calcium. Intact PTH was very high (3050 pg/ml: normal 9–55 pg/ml). On neck examination 3×2 cm nodule was palpable.With the report of high PTH and high calcium diagnosis of primary hyperparathyroidism was made with the doubt whether it’s a palpable parathyroid carcinoma with bone metstasis. USG neck revealed hypoechoic lesion posterior to left inferior lobe of thyroid of 3.6 cm. As no MIBI scan was available in the vicinity, we went ahead with exploration. 4×3 cm lesion was found adherent to thyroid. Therefore enbloc excision was done with hemithyroidectomy. After resection, the patient’s serum levels of calcium, alkaline phosphatase, and intact-PTH normalized Postoperatively patient developed clinical and biochemical hypocalcemia and managed with calcium infusion. Histopatholgy turned out to be parathyroid adenoma.

Conclusion: Palpable parathyroid tumor, advanced skeletal and very high serum calcium with parathyroid hormone levels are considered strong predictors of parathyroid carcinoma. Most of these features are common in Indian primary hyperparathyroidism (PHPT) patients although only few have Parathyroid carcinoma [1].

Reference: [1] Agarwal G, Prasad KK, Kar DK, Krishnani N, Pandey R, Mishra SK. Indian primary hyperparathyroidism patients with parathyroid carcinoma do not differ in clinicoinvestigative characteristics from those with benign parathyroid pathology. World J Surg. May 2006 30(5):732–42.