A CONCURRENT FINDING OF A GROWTH HORMONE-PRODUCING PITUITARY ADENOMA AND A RADIOLOGICALLY- CONFIRMED SYMPTOMATIC RATHKE’S CLEFT CYST

Abstract

BACKGROUND
We present a case report describing a rare finding of concurrent growth hormone (GH)-producing pituitary adenoma and a radiologically confirmed symptomatic Rathke’s cleft cyst (RCC) in a 65-year-old female patient.

CASE
Hormonal studies showed elevated insulin-like growth factor (IGF) [43.3 nmol/L, reference range (RV) 6.2-24 nmol/L and 51.3 nmol/L] taken two months apart. Other assays were normal (PRL 213 mIU/L, RV <700; 1000H cortisol 222 nmol/L, RV 14-690; TSH 1.3 mIU/L, RV 0.27-4.2; FT4 12 pmol/L, RV 12-22 pmol/L). OGTT revealed a failure to suppress serum GH to <1 μg/L, with nadir GH 2.3 μg/L. Pituitary meatus magnetic resonance imaging scan showed a 6.5 mm x 9 mm non-enhancing cyst in the pituitary sella which appeared to be displacing the normal pituitary tissue superiorly and slightly posteriorly. The optic chiasm was preserved, with no supra- or parasellar extension. After transphenoidal surgery, histolopathologic studies revealed a strongly GH-positive adenoma, also positive for PIT1, SF1; and Ki67 1-2%. PRL, FSH and LH staining were negative.

CONCLUSION
Clinicians are reminded about increasing evidence of the concurrent occurrence of symptomatic RCC(s) and pituitary adenoma(ta). More explanations beyond case reports or case series evidence are needed to explain their seeming concurrence.