Endobronchial ultrasound-guided biopsy to diagnose large posterior mediastinal parathyroid adenoma prior to video-assisted thoracoscopic resection

Parathyroid Carcinoma Causing Mild Hyperparathyroidism in Neurofibromatosis Type 1: A Case Report and Systematic Review

BACKGROUND

Neurofibromatosis type 1 is an autosomal dominant disorder characterized by an increased incidence of tumors, including endocrine ones. Primary hyperparathyroidism can be rarely caused by a parathyroid carcinoma; these patients are generally characterized by severe symptoms, large neck lesions and high levels of PTH and calcium. We report a case of hyperparathyroidism due to parathyroid carcinoma in a patient affected by neurofibromatosis type 1. A systematic review of the literature was also conducted.

PATIENT FINDINGS

A 56-year-old woman was referred for a 13 mm-nodular lesion of the neck incidentally discovered on ultrasound examination and mild hyperparathyroidism. A 99mTctetrofosmin/ pertechnetate subtraction scintigraphy was negative for parathyroid disease. Given the absence of suspicious ultrasound finding, a fine-needle aspiration cytology was performed with iPTH determination in the aspirate, confirming the parathyroid origin of the lesion. The patient underwent left inferior parathyroidectomy with intraoperative monitoring of iPTH and became normocalcemic. On histopathological examination, parathyroid carcinoma presenting at the resection margin was diagnosed, thus a surgery revision was requested.

CONCLUSION

Even if literature does not support a syndromic association between neurofibromatosis type 1 and primary hyperparathyroidism, the benefit of precociously diagnosing and treating this condition may outweigh costs associated with screening. This case report moreover demonstrates that sometimes clinical, laboratory and imaging aspects suspicious for cancer may be missing. A prompt referral to a high-volume center is crucial for the management of those cases of incidental histopathological diagnosis.

Endoscopic Ultrasound-guided Transesophageal Biopsy of Parathyroid Adenoma

Parathyroid adenoma (PTA) causing hyperparathyroidism and hypercalcemia leading to pancreatitis is reported. Endoscopic ultrasound (EUS) can help in the localization of PTA. We report a case of EUS-guided fine-needle aspiration biopsy-proven PTA which is not reported in literature to our knowledge.