Cervicomediastinal Hematoma: Atypical Presentation of a Parathyroid Carcinoma.

Parathyroid carcinoma (PC) is a rare endocrine neoplasm that typically presents with osteopenia/osteoporosis, nephrolithiasis, asthenia, and neuropsychiatric symptoms. We describe the case of a 48-year-old woman, presenting with a large painful hematoma in the cervicomediastinal area. The neck ultrasound (US) demonstrated a solid lesion measuring 40 × 80 × 55 mm, markedly hypoechoic, which extended from the right thyroid lobe to the mediastinum. The blood tests showed elevated serum calcium and parathyroid hormone (PTH) concentrations, consistent with hypercalcemic primary hyperparathyroidism. The patient was rehydrated and treated with furosemide, cholecalciferol, and bisphosphonate, and underwent right lower parathyroidectomy, right hemithyroidectomy, and lymphadenectomy of the right VI cervical level. Histological examination was diagnostic for nonangioinvasive or neuroinvasive PC, and the thyroid lobe was the site of lymphocytic thyroiditis; all removed lymph nodes were benign. The postoperative course was regular. Postoperative neck US showed a hypoechoic left thyroid lobe without evidence of residual neoplasm in the right thyroid bed. Levothyroxine therapy of 50 mcg/day was started because of serum thyrotropin concentrations elevated at 18 mcIU/mL (normal reference range, 0.35-4.0 mIU/mL). Eight years after diagnosis, the patient is in good general condition, with no clinical, biochemical, or imaging evidence of disease persistence/recurrence.