SAT-252 A Rare Case of Crooke’s Adenoma

BACKGROUND: Crooke’s cell adenoma is a rare variant of ACTH-secreting corticotroph adenomas (<1%). These are aggressive macroadenomas and usually invade the cavernous sinus producing visual symptoms. Clinical Case: A 48-year old male presented with acute right eye and right temple pain, and diplopia that started 6 days prior. Past medical history included hypertension, type 2 diabetes, hyperlipidemia, traumatic brain injury, CSF leak with bacterial meningitis s/p sphenoid repair and palsy of the right III, V and VI cranial nerves. Head CT showed a 1.9 x 2.1 x 1.5 cm soft tissue-density mass medial to the right cavernous carotid artery extending into the sphenoid sinus. There was expansile bony change to the floor and right dorsum of the sella. The mass showed mild contrast enhancement and abutted the superior orbital fissure. A brain MRI was not obtained due to history of a left cochlear implant. He did not have any cushingoid features on exam. Neuro-ophthalmology exam revealed, severe sixth cranial nerve palsy, bilateral optic disc pallor and a mild right superotemporal visual field defect. Pre-operative pituitary function tests revealed ACTH 103 pg/ml (7–63), cortisol 14 ug/dl (6.0–18.4), FSH 2.7 mIU/ml (1.5–12.4), LH 3.8 mIU/ml (1.7–8.6), prolactin 17.6 ng/ml (4–15.2), total testosterone 175 ng/dl (249–836), TSH 1.10 uIU/ml (0.27–4.20), free T4 0.67ng/dl (0.8–1.8) and IGF-1 208 ng/ml (69–224). He underwent successful endoscopic trans-sphenoidal resection of a 4.2 x 2.5 x 0.5 cm mass. Pathology revealed hyaline deposits in the cytoplasm and perinuclear cytokeratin in more than 50% of the adrenocorticotroph cells consistent with Crooke’s cell adenoma. Post-operatively, his right eye pain and abduction deficit improved, and diplopia returned to baseline. He was placed on a short hydrocortisone taper. Due to high risk of recurrence, he received 54Gy in 30 fractions to the sella. Six and 12-month follow-up head CTs revealed stable residual enhancing tissue. Pituitary function tests done 9 months post-surgery were normal and no hormone replacement was needed. He was clinically stable 12 months after surgery. Conclusion: We described a rare case of invasive Crooke’s cell pituitary adenoma with visual disturbances that was managed with resection and radiotherapy. The patient remained free of recurrence 1 year later. However, lifetime surveillance is necessary due to high incidence of recurrence. Reference: 1. Crooke’s Cell Tumors of the Pituitary. Neurosurgery, Volume 76, Issue 5, May 2015, Pages 616–22