Endocrine Abstracts

Background: The aim of this report is to describe a fortuitely discovered association between parathyromatosis and occult sclerosing papillary carcinoma of the thyroid.

Case description: A 56-year-old woman presented with pyelic relapsed stone, bone pains and iPTH=348 ng but normal calcemia as manifestations of recurrent primary hyperparathyroidism after a right inferior parathyroid adenoma resection done elsewere 6 years ago Sonography showed a 5 mm hypo and isoechoic zone at the lower pole of the right lobe of the thyroid with irregular tracer activity at the parathyroid scan. At the operation done in a ‘hostile’ surgical field an unbounded mass was identified lateral and below the thyroid pole extending in the thyrothymic ligament together with several graytan nodules of 1–3 mm scattered on distal surface of the thyroid lobe and also in the areolar fibrofatty atmosphere of the tracheoesophageal groove. Excision and biopsy of the mass and of two main nodules showed the presence of parathyroid tissue and the intervention is finally completed with a near-total thyroid lobectomy including about 4 cm of thyrothymic ligament retrosternally. Pathology evidencied multiple poorly outlined nests of parathyroid cells but also a minute focus of papillary sclerosing thyroid carcinoma. One year after operation the patient is well-doing without any local recurrence and normal biological parameters.

Discussion: Coexistence between parathyromatosis – a rare but challenging cause of re-current hyperparathyroidism – and thyroid occult carcinoma, a more frequent encountered lesion is an entirely coincidental ocurrence. The preoperative diagnosis of both conditions particularly of the latter one – is rarely proved, these lesions being unlikely clinically significant. There is almost always a history of previous parathyroidectomy therefore in such intraoperative fortuitely findings, the resection for parathyromatosis include also an en bloc thyroid lobectomy with superior retrosternal tissue removal. The further therapy of coincidental thyroid carcinoma is conditioned by its clinical and pathological characteristics.

Conclusions: Preoperative and intraoperative evaluation for recurrent primary and renal hyperparathyroidism must be meticulous and complete considering possible coexisting thyroid lesions. Indeed to our knowledge there have been no reports in the literature mentioning this unprecedented entity the over described entity.