U028

A Difficult Case of Hypercalcaemia

D Shrestha, R Banerjee, F Palazzo, J Anderson, D Ravichandran

Luton and Dunstable Hospital.

Abstract:

A fifty year old female presented with primary hyperparathyroidism in 2010. At presentation her corrected serum calcium was 3.61 (2.1 – 2.6)mmol/l, PTH 70.8 (1.5 – 7.7) pmol/l and 24 hours urine calcium 25.5 (2.5 – 7.5) mmol/l.

Sestamibi and Ultrasound (US) scans were not helpful in the localisation of abnormal parathyroid gland but US showed bilateral thyroid enlargement with a suspicious nodule in the left lobe. US guided FNA was reported as THY4, suggesting co-existing thyroid carcinoma. She underwent total thyroidectomy and central compartment neck dissection. The left thyroid mass was adherent to oesophagus and was mobilised. Three normal parathyroid glands were identified and preserved but one left sided parathyroid was not identified.  Histology (confirmed by a second opinion) showed parathyroid carcinoma arising in an adenoma with lymphovascular invasion; 5 lymph nodes were negative. Postoperatively the serum calcium normalised. The case was discussed in the local MDT and was also referred to a tertiary centre for second opinion and the decision was just to offer follow-up.

After 2 years of uneventful follow-up both her calcium and PTH were found to be raised. Neck examination was normal and loco-regional recurrence in the neck was ruled out by imaging (US, MIBI, MRI and CT). However they revealed bilateral lung nodules suggestive of metastatic disease. She was discussed in local and tertiary centre MDT’s again and was started on cinacalcet for hypercalcaemia. However, serum calcium became too difficult to control despite maximum dose of cinacalcet. A repeat CT showed an increase in the size of pulmonary nodules. She was referred to a thoracic surgeon for consideration of metastasectomy. She underwent bilateral metastasectomies, first on the left side followed by the right 5 months later. Wedge resections of all palpable lung nodules were performed. Following this the calcium normalised briefly but started to increase after 2 months. CT done 3 months after the last metastacectomy showed further nodules in the lung. However the calcium is now easily controlled by cinacalcet. Further metastacectomy or radiofrequency ablation of the lung metastases would be considered if it becomes more difficult to control.

This lady is now over 2-years post-diagnosis of metastatic parathyroid carcinoma and is relatively very well and is still working. This case illustrates the challenges in the diagnosis and management of parathyroid carcinoma and the role of metastasectomy in the control of intractable hypercalcaemia from metastatic disease.