El adenoma de célula madre acidófila es un tumor hipofisario parcialmente diferenciado derivado del precursor común de células productoras de hormona de crecimiento y prolactina. Son poco frecuentes y clínicamente pueden presentarse como no uncionantes o asociar hiperprolactinemia.
Se analizaron los hallazgos clínicos, inmunohistoquímicos y ultrastructurales de 3 casos de este tipo de adenoma hipofisario. Dos de ellos (2 varones, casos 1 y 3), comenzaron con clínica de compresión local y panhipopituitarismo, y el restante (mujer, caso 2), con amenorrea secundaria. Eran 3 macroadenomas hipofisarios, y en el caso 3 había invasión del seno cavernoso. En todos se detectó hiperprolactinemia y sólo en 1 (caso 3) se asociaba acromegalia. Dos de los pacientes fueron intervinenidos con abordaje transesfenoidal con extirpación completa, y no existió recidiva tumoral en el seguimiento posterior. El estudio inmunohistoquímico y la microscopia electrónica confirmaron el diagnóstico.
La presentación clínica de nuestros casos es eterogénea. La extirpación completa del adenoma, si es posible, es el principal factor pronóstico.
Acidophil stem cell adenoma is an incompletely differentiated pituitary neoplasm consisting of a single cell type, assumed to be a common progenitor of somatotropes and lactotropes. These tumors are uncommon and may appear clinically as non-functioning adenomas; varying degrees of hyperprolactinemia are present in most cases.
In this series, clinical, histopathological, immunohistochemical and ultrastructural characteristics of three cases of stem cell adenoma are described.
Two patients (two males, cases 1 and 3) presented with symptoms of local compression and panhypopituitarism. In the remaining patient (female, case 2) the pituitary tumor was detected because of secondary amenorrhea. The tumors consisted of three pituitary macroadenomas with invasion of the cavernous sinus only in case 3.
Hyperprolactinemia was present in all three patients. Acromegaly was evident in one patient (case 3).
Complete transsphenoidal removal was achieved in two patients who have shown no evidence of tumoral recurrence in subsequent follow-up. The diagnosis was confirmed by electron microscopy and immunohistochemical characteristics.
In our series, the clinical features of the tumors were heterogeneous. If is possible, complete surgical removal confers a better prognosis.