Left supraclavicular parathyroid carcinoma: diagnostic difficulties through a case report.

Parathyroid carcinoma is a very rare malignant tumour of the parathyroid gland, accounting for less than 0.005% of all cancers, and less than 1% of the aetiologies of primary hyperparathyroidism. This case report aims to describe the incidental discovery of a non-secreting parathyroid carcinoma in a left supraclavicular location and to report on the diagnostic difficulties encountered, together with a review of the literature and current management issues. A 43-year-old female presented with a left supraclavicular swelling with no associated signs. Imaging revealed left supra-clavicular adenopathy (Troisier lymph node) associated with a hetero-multi-nodular goiter classified EU-TIRADS 5. The abdominopelvic region was strictly normal. The patient underwent a total thyroidectomy with a left mediastino-recurrent curage and a homolateral laterocervical functional curage. Pathological examination was consistent with parathyroid carcinoma in the left supraclavicular region.