Incidental finding of Ectopic Retrosternal Parathyroid Adenoma in a patient operated for Controlled toxic multinodular goiter, rare case report

Background Ectopic parathyroid adenomas represent a diagnostic challenge, since they are extremely rare in clinical practice but the incidentally detected retrosternal components are extremely rare. Case Presentation We present a case of a 51 years old female patient presented with anterior neck swelling of 15 years duration with hot intolerance, fatigue and palpitation in recent 2 years. She has no remarkable medical, surgical or family history. On examination during her initial visit, pulse rate was 96 beats/minute and there was bilateral multi nodular anterior neck swelling that moves with swallowing. Thyroid function test was suggestive of low thyroid stimulating hormone (TSH) for which she took anti-thyroid drugs for one year and optimized. While subtotal thyroidectomy was being done, there was about 5*3*3 centimeter oval retrosternal well encapsulated mass with no continuity with the thyroid tissue. The mass was removed with no significant difficulty and histopathologic examination was suggestive of Colloid goiter + Parathyroid adenoma. Clinical discussion Ectopic parathyroid adenomas represent a diagnostic challenge, since they are extremely rare in clinical practice. Most case reports shows that the incidentally detected parathyroid adenomas were at their usual anatomic location but what makes our case different is that, she was normocalcemic, the adenoma was retrosternal at anterio-superior mediastinum and very large in size (5*3*3 CM) too. Conclusion Pre-operative normocalcaemia does not preclude parathyroid disease. Any abnormally large soft tissue at the vicinity of the thyroid gland during surgery should be thoroughly evaluated and possibly excised.