Doble adenoma ectópico de paratiroides inferior derecha como causa de hiperparatiroidismo primario

Abstract

Introduction and objective: To describe a case of double ectopic adenoma of the right lower parathyroid gland whose existence was unknown preoperatively as a cause of primary hyperparathyroidism and a potential cause of recurrence if it remains unnoticed Method: A 47-year-old woman affected by primary hyperparathyroidism case with surgical criteria established by our Thyroid and Parathyroid Pathology Committee, with a positive locator study by 99mTc SESTAMIBI SPECT-CT and ultrasound at the level of the lower pole posterior to the gland juxtaesophageal thyroid is reported. Selective parathyroidectomy was planned by the Thyroid Pathology Unit of the Otorhinolaryngology Service, identifying a tumor compatible with the adenoma in the aforementioned region. Results: During surgical dissection, a virtual fibrous resistance and traject were observed t towards a second tumour of similar size in a more retroesophageal location. En bloc extraction with the first neoplasm was performed. A decrease in 15´PTH to 20 pg/ml (>50% of the baseline level of 626) was observed intraoperatively after excision was completed. The postoperative period occurred without complications. The patient has not experienced a recurrence in 36 months. Both tumors were reported as parathyroid adenoma. Retrospectively, all the available imaging tests were analyzed and in a Nuclear Magnetic Resonance performed for another reason, the second tumor seemed to be intuited, although it was not conclusively demonstrated. Discussion: During parathyroidectomy for primary hyperparathyroidism, the discovery of an enlarged or multiple parathyroid gland or "innocent adhesion" creates a dilemma regarding the need for further exploration with the consequent added risk, especially if it is in an ectopic location and if the location studies do not reflect this eventuality. Although the iPTH test can contribute to solve this problem out in theory, the literature shows that by itself it is not reliable to rule out the existence of multiple or bilobed adenomas. The use of additional detection systems, such as nuclear or autofluorescence based methods, may be useful, although their availability is not universal. Some indices, such as the Wisconsin index, which relate PTH to gland weight, have been proposed to determine the risk of a second occult adenoma, although their usefulness has yet to be studied. In our patient, the key was a meticulous, careful and gentle dissection. This procedure revealed an adherence and resistance that, like a minimal isthmus, led us to the second tumor. We do not know for sure if they were two ectopic adenomas or a bilobed adenoma since, although they constitute two completely intact and apparently independent spheres with a virtual union , their close proximity and the existence of that minimal threadlike path seem to reflect a certain relationship between them, and therefore a double adenoma diagnosis was given. Conclusions: The presence of multiple or lobulated adenomas constitutes a source of recurrence or persistence of postoperative primary hyperparathyroidism. To minimize this risk, adequate pre-surgical localization study, intraoperative if available, adaptation of the surgical technique, with a meticulous and gentle exploration to avoid leaving fragments and second adenoma are recommended.