Adenomas of cervical maldescended parathyroid glands: pearls and pitfalls

Abstract

Background: Missed parathyroid adenoma (PTA) is the commonest cause of persistent hyperparathyroidism. Although many are subsequently found in well-described locations, some are found in unusual regions of the neck. This paper presents the combined experience of three large tertiary endocrine surgery centres with maldescended PTA (MD-PTA).

Methods: Patients were recruited from the endocrine surgical databases of three tertiary endocrine surgery units. Patients with PTA found >1 cm above the superior thyroid pole or other cervical locations as a result of abnormal or incomplete descent were included for analysis.

Results: MD-PTA was identified in 16 patients out of a total of 5241 patients who had undergone parathyroidectomies in the 7-year study period (incidence 0.3%). Seven (44%) patients had minimally invasive parathyroidectomy, while nine (56%) had bilateral neck exploration. The mean excised gland weight was 750 + 170 mg. Cure was achieved in all patients with a minimum follow-up of 6 months. The locations of MD-PTA in this study included submandibular triangle, retropharyngeal space, carotid sheath (at carotid bifurcation and intravagal), parapharyngeal space (superior to thyroid cartilage or superior thyroid pole) and cricothyroid space.

Conclusions: Despite their rare occurrence, incompletely or abnormally descended PTAs can be encountered by any surgeon who performs parathyroidectomies. It is important to develop a strategy to systematically locate these glands. High cure rates can still be achieved with minimally invasive parathyroidectomy if confident preoperative localization is available. A sound knowledge of embryology and a thorough exploration also facilitate an overall high success rate with open exploration.

Keywords: adenoma; ectopic; high cervical; hyperparathyroidism; parathyroid; parathyroidectomy; undescended.