Nonfunctional parathyroid carcinoma

Abstract

Purpose: Nonfunctional parathyroid carcinoma (PTC) is one of the rarest malignant diseases and only nine cases have been reported during the last 23 years. We present a case of nonfunctioning PTC and review the literature in an effort to provide a better understanding of this rare disorder.

Methods: One patient with nonfunctioning PTC was presented, detailing the clinical features, histologic findings, diagnosis, and treatment. Together with data from the other nine cases reported last 23 years, the related literature is also reviewed.

Results: The presented case was a 47-year-old man with a 2-month history of an enlarging painless cervical mass followed by a 2-week history of hoarseness. Clinical and laboratory evaluations failed to reveal evidence of hyperparathyroidism. Pathological analysis of the resected tumor disclosed findings consistent with PTC. The nonsecretory state of the tumor was further supported by immunoreactivity for parathyroid hormone in tissue, and normal serum levels of this peptide and calcium preoperatively and postoperatively.

Conclusion: Most nonfunctional PTC is detected late due to a paucity of symptoms, of which a palpable neck mass is the most common. Patients with nonfunctioning PTC appear to have a poorer prognosis than do those with functioning parathyroid cancers.

Fig. 1

Cervical computed tomography scan showed one solid mass of 3.6 × 2.2 cm (a) located in middle and lower portion of left thyroid (black arrow) and an enlarged lymph node (white arrow); and the solid mass of 2.3 × 1.9 cm (b) lay posterior to the inferior pole of left thyroid lobe (correspond to the left inferior parathyroid gland area)

Fig. 2

Histological appearance of nonfunctional parathyroid carcinoma. a Pseudocapsular invasion of tumor cells (black arrow) (HE stain ×40). b Vascular invasion of tumor cells in the pseudocapsule (black arrows) (HE stain ×40). c Invasion of tumor cells into thyroid gland (HE stain ×40). d Lymph node metastasis of parathyroid carcinoma (L lymph granules and T tumor) (HE stain ×40)