April 2020 Highlights Medical Corner


PNA Medical Corner: Gamma Knife and Crooke’s Cell Adenoma

jason sheehanThis month the PNA Medical Corner features a study co-authored by PNA member Dr. Jason Sheehan,a neurosurgeon with the University of Virginia. The study finds that gamma knife radiosurgery is effective in treating the rare Crooke’s cell pituitary adenoma.

World Neurosurg. 2020 Apr 3. pii: S1878-8750(20)30623-9. doi: 10.1016/j.wneu.2020.03.152. [Epub ahead of print]
Gamma Knife Radiosurgery in Patients with Crooke's Cell Adenoma.
Snyder MH, Shabo L, Lopes MB, Xu Z, Schlesinger D, Sheehan JP.
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Crooke cell adenoma (CCA), is a very rare subtype of pituitary neoplasm which is known to be clinically aggressive. They can secrete adrenocorticotropic hormone, or may be endocrinologically silent. We aim to evaluate the effect of Gamma Knife radiosurgery (GKRS) on endocrine remission and tumor control.



A total of five patients (2M/3F, median age at GKRS, 55 years, and range from 21 to 65 years) with a pathology-confirmed CCA treated with GKRS at Gamma Knife Center of the University of Virginia constituted this study. The median time interval between TSR and GKRS was 5.8 months. The median margin dose was 25Gy (range, 18Gy to 25Gy). Median treated adenoma volume was 3.12cc. The median follow-up was 107 months (range, 44 to 122 months).


Tumor control was achieved in all patients. Three patients achieved endocrine remission at the last follow-up. The median time interval to cortisol normalization when off of anti-hormone secreting medication was 12 months (range, 6 to 24 months). Newly developed or worsening endocrinopathy occurred in 3 patients at the time interval of 6, 15, and 18 months, respectively. Cranial nerve (CN) III neuropathy developed in 1 patient. Two patients required bilateral adrenalectomy at 44 months and 50 months following GKRS, respectively.


GKRS appears to be a safe and reasonably effective treatment option for CCA. Larger numbers of patients from a multicenter study are needed to verify these findings.