Pituitary macroadenoma with persisting dense lymphocytic infiltration in a young male patient.
BACKGROUND
Lymphocytic anterior hypophysitis in association with a pituitary adenoma was reported previously. In rare instance, inflammatory infiltration was confined to adenoma tissue itself, excluding anterior pituitary.


METHODS
The patient - a 27-year-old male - presented with visual field defect. Further examination revealed a pituitary mass with suprasellar extension. Hormonal evaluation indicated mild hyperprolactinemia (42 ng/ml, normal < 19). After transsphenoidal resection, a pituitary adenoma showing cytoplasmic immunoreactivity to prolactin was identified. Dense and diffuse lymphocytic infiltration was seen within the tumor. At 15th month, a second transsphenoidal operation was necessary because of rapid development of visual compromise and headache. Excised surgical specimen consistent with previously resected adenoma showed diffuse lymphocytic infiltration composed of B and T cells within the adenoma tissue again.


CONCLUSIONS
Presence of dense, hypophysitis-like lymphocytic infiltration within pituitary adenoma tissue obtained by two consecutive operations may reflect an host-mediated immune reaction to tumor. This rare finding could be challenging in terms of differential diagnosis and follow-up course.
Department of Pathology, Department of Neurosurgery and Department of Medicine, Division of Endocrinology, Istanbul University, Istanbul Medical Faculty, Istanbul, Turkey.
E
E
Cakir
C
C
Bayindir
P A
PA
Sabanci
M
M
Imer
N C
NC
Ozbey
D000236:Adenoma; D003937:Diagnosis, Differential; D006801:Humans; D007018:Hypopituitarism; D008297:Male; D010900:Pituitary Diseases; D010911:Pituitary Neoplasms