ATYPICAL PARATHYROID ADENOMA. SERIES OF 3 CASES OF SURGICALLY INTERVENED HYPERPARATHYROIDISM

AUTHORS:
B. Gómez Molina (Cartagena (Murcía), Spain) , C. Gijón Román (Cartagena (Murcía), Spain) , M.D. Balsalobre Salmerón (Cartagena (Murcía), Spain) , M.A. García López (Cartagena (Murcía), Spain) , P. Rodríguez García (Cartagena (Murcía), Spain) , E. Crespo Álvarez (Cartagena (Murcía), Spain) , J. García Urban (Cartagena (Murcía), Spain) , J.L. Vázquez Rojas (Cartagena (Murcía), Spain)
Background:
Primary hyperparathyroidism is caused bythe presence of parathyroid adenoma(80%), parathyroid hyperplasia(15%),carcinoma(1.3%) and atypicaladenoma(<1%). It is defined as "adenoma with characteristics ofcarcinoma, lacking invasive growth", presents with elevated calcium levels. It isa challenge, especially when itcomes todifferentiating it from parathyroid carcinoma.
Methods:
We present a series of3 cases, in which patients presented with symptomatic hypercalcemia and hyperparathyroidism; thestudy was completed with cervical ultrasound and scintigraphy with adenomaparathyroid pattern. They underwent scheduled surgery, performing selective parathyroidectomy and in one of them hemithyroidectomy dueto suspected malignancy. In all cases theintraoperative PTH values decreased after gland extraction. The pathological anatomy result describes fibroustracts, with nests of cells in the capsule and adjacent adipose tissue, as wellas absence of invasive growth. The patients had a favorable evolution, with normalization of analyticalvalues.
Results:
Atypical parathyroid adenoma shares clinicaland histological characteristics with parathyroid carcinoma, however, itpresents a benign course of the disease and lacks invasive growth. The diagnosis is made with blood tests(hypercalcemia and elevated PTH)and imaging tests to guide thelocation. During surgery, the enlargedparathyroid is located and itsexcision is performed; it usually appears as a soft, enlarged gland. The pathological anatomy describes the presence of capsular fibrous invasion with bands fibrotic with trabecular growth without evidence of malignancy due to the absenceof invasive growth, which is suggestive of atypical adenoma. Postoperative follow-up using analytical andultrasound monitoring is recommended(3% recurrence).
Conclusions:
Atypical parathyroid adenoma isan entity to take into account in cases ofhypercalcemia. Diagnostic imaging with cervical ultrasound, scintigraphy orPET-CT, is essential, as well as appropriate surgical treatment. It is important to make adifferential diagnosis with parathyroid cancer.