title: Silent corticotroph adenomas after stereotactic radiosurgery: a case-control study.
abstract: OBJECTIVE
  To investigate the safety and effectiveness of stereotactic radiosurgery (SRS) in patients with a silent corticotroph adenoma (SCA) compared with patients with other subtypes of non-adrenocorticotropic hormone staining nonfunctioning pituitary adenoma (NFA).
  
  
  METHODS
  The clinical features and outcomes of 104 NFA patients treated with SRS in our center between September 1994 and August 2012 were evaluated. Among them, 34 consecutive patients with a confirmatory SCA were identified. A control group of 70 patients with other subtypes of NFA were selected for review based on comparable baseline features, including sex, age at the time of SRS, tumor size, margin radiation dose to the tumor, and duration of follow-up.
  
  
  RESULTS
  The median follow-up after SRS was 56 months (range, 6-200 months). No patients with an SCA developed Cushing disease during the follow-up. Tumor control was achieved in 21 of 34 patients (62%) in the SCA group, compared with 65 of 70 patients (93%) in the NFA group. The median progression-free survival (PFS) was 58 months in the SCA group. The actuarial PFS was 73%, 46%, and 31% in the SCA group and was 94%, 87%, and 87% in the NFA group at 3, 5, and 8 years, respectively. Silent corticotroph adenomas treated with a dose of ≥17 Gy exhibited improved PFS. New-onset loss of pituitary function developed in 10 patients (29%) in the SCA group, whereas it occurred in 18 patients (26%) in the NFA group. Eight patients (24%) in the SCA group experienced worsening of a visual field deficit or visual acuity attributed to the tumor progression, as did 6 patients (9%) in the NFA group.
  
  
  CONCLUSIONS
  Silent corticotroph adenomas exhibited a more aggressive course with a higher progression rate than other subtypes of NFAs. Stereotactic radiosurgery is an important adjuvant treatment for control of tumor growth. Increased radiation dose may lead to improved tumor control in SCA patients.
authors.affiliation: Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia.
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia.
authors.forename: Scott
authors.initials: S
authors.lastname: Ellis
authors.affiliation: Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia.
authors.forename: Cheng-Chia
authors.initials: CC
authors.lastname: Lee
authors.affiliation: Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Starke
authors.affiliation: Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia; Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia.
authors.forename: David
authors.initials: D
authors.lastname: Schlesinger
authors.affiliation: Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia; Department of Internal Medicine, University of Virginia, Charlottesville, Virginia.
authors.forename: Mary
authors.initials: M
authors.lastname: Lee Vance
authors.affiliation: Division of Neuropathology, University of Virginia, Charlottesville, Virginia.
authors.forename: M Beatriz
authors.initials: MB
authors.lastname: Lopes
authors.affiliation: Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia; Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia. Electronic address: jsheehan@virginia.edu.
authors.forename: Jason
authors.initials: J
authors.lastname: Sheehan
mesh_terms: D049913:ACTH-Secreting Pituitary Adenoma / Q000378:metabolism / Q000601:surgery*; D000236:Adenoma / Q000378:metabolism / Q000473:pathology / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007018:Hypopituitarism / Q000209:etiology; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000378:metabolism / Q000601:surgery*; D016634:Radiosurgery / Q000009:adverse effects / Q000379:methods*; D011879:Radiotherapy Dosage; D014792:Visual Acuity / Q000528:radiation effects; D014794:Visual Fields / Q000528:radiation effects; D055815:Young Adult