Endocrine Abstracts

A 50-year-old woman was admitted to hospital feeling unwell.

Biochemistry: Calcium 3.46 (2.15–2.6),PO4 0.42 (0.8–1.5), AlkalinePhosphatase 259 (30–95). She had been diagnosed 3 years ago with Carcinoma breast and had undergone surgery,chemotherapy and radiotherapy. Regular follow-up had not shown any recurrence.

No breast lump or bony tenderness was recorded.

Further biochemistry: PTH 30 (0–6.4), PTHrp <0.7 (<1.8) and Vit D 21.5 (6–40). Ultrasound neck did not show parathyroid lump or adenoma. Sestamibi scan showed a focus of increased uptake-posterior to left lower lobe thyroid. Calcium stayed elevated between 3.4–3.9 inspite of fluids, Pamidronate infusion and frusemide. Parathyroidectomy of Right upper,lower and Left parathyroid was undertaken (no adenoma noted). No other PTH tissue noted after extensive neck exploration.

Liver function subsequently deranged and an ultrasound abdomen showed a 2.5 cm lesion near the portal vein- confirmed on CT scan. Clinical examination showed a sternal mass. Biopsy showed a metastatic lesion with possible breast primary. Calcium stayed elevated (3.75), she was transferred to oncology and started on chemotherapy and steroids. Biochemistry: Ca 3.77, PO4 0.58, PTH 48.9; Vit D 16.2.

Repeat sestamibi: increased activity in lower mediastinum at level of base of heart. CT chest did not reveal any ectopic parathyroid tissue. Calcium stayed resistant to treatment (3.78) and she was started on Cinacalcet 30 mg. Further assessment showed her sternal mass and liver lesion to have to have resolved.

She was further admitted to hospital with tetany (Ca 1.73). Cinacalcet was stopped and she was started on Calcichew D3 tablets. At present, she continues to be under endocrine and oncological review.

We present a rare case of possibly true PTH secreting breast metastasis. This patient’s calcium settled as soon as her recurrence was treated. The raised PTH prompting the search for a parathyroid adenoma and parathyroidectomy was possibly due to the tumor itself.