Silent corticotroph adenomas have unique recurrence characteristics compared with other nonfunctioning pituitary adenomas

Abstract

Objective: The prevalence of silent corticotroph adenomas (SCAs) is not rare among nonfunctioning pituitary adenomas (NFPAs); however, it is unknown whether the clinical significance of SCAs differs from that of NFPAs without ACTH immunoreactivity (non-SCAs). Our goal was to compare the clinical characteristics and natural history between patients with SCAs and non-SCAs.

Design/patients: We reviewed the medical records of all patients who underwent transsphenoidal surgery for NFPAs from January 1990 to October 2007 at the Seoul National University Hospital.

Measurements: We analysed whether clinical manifestations at diagnosis, postoperative recurrence rate and recurrence characteristics differed between SCA and non-SCA patients.

Results: In total, 28 patients with SCAs and 134 patients with non-SCAs were analysed. The mean age at the time of diagnosis was 44 years (range, 13-67 years) in the SCA group and 50 years (18-79 years) in the non-SCA group (P = 0.026), with respective follow-up periods of 5.2 (range, 1.0-16.0 years) and 4.2 years (0.5-16.1 years) (P = 0.255). Overall recurrence rates of SCAs and non-SCAs were 25.0% and 26.9% respectively (P = 0.839). More than two recurrences (P = 0.001) and recurrence after more than 5 years (P = 0.040) were associated with SCAs. Multiple recurrences of SCAs were confined to younger patients.

Conclusion: The overall recurrence rate was similar between SCAs and non-SCAs. However, young patients with SCAs had a higher frequency of multiple and late recurrences, which showed more aggressive tumour behaviour. Therefore, we suggest that patients with SCAs, especially patients diagnosed at a young age, require careful long-term monitoring.