Recurrence in silent corticotroph adenomas after primary treatment: A systematic review and meta-analysis.

CONTEXT

2017 WHO Classification of Pituitary Tumors grades silent corticotroph adenomas (SCAs) as "high-risk adenomas" due to their aggressive clinical behavior (high probability of recurrence). However, studies comparing recurrence rates of SCAs with other non-functioning pituitary adenoma (NFPAs) subtypes have provided conflicting results.

OBJECTIVE

Estimate recurrence rates of SCAs after primary treatment (surgery±radiotherapy) and recurrence rate ratios (RRR) between SCAs and other NFPA subtypes.

METHODS

Systematic review of published literature reporting on outcomes of SCAs up to October 31, 2017 was conducted. Recurrence rates, RRRs, 95% confidence intervals (CIs) were estimated from each study and pooled using random effects meta-analysis model.

RESULTS

For determination of SCAs recurrence rates, 14 studies (low risk of bias, 297 patients) were selected; recurrence rate was 5.96 (95% CI, 4.3-7.84) per 100 person-years. Based on studies with mean follow-up <5 or ≥5 years, 25% (cumulative incidence 0.25; 95% CI, 0.13-0.38) and 31% (cumulative incidence 0.31; 95% CI, 0.23-0.40) of SCAs had recurrence, respectively. Recurrence rates after surgery or surgery+radiotherapy were 5.41 (95% CI, 3.28-7.96) and 4.88 (95% CI, 0.67-11.54) cases per 100 person-years, respectively. Analysis of 10 eligible studies (moderate risk of bias, 244 SCAs, 1622 NFPAs) showed no significant RRR (1.44; 95% CI, 0.9-2.33, p=0.130) between the groups. Focus on tumors treated solely by surgery also revealed no significant RRR (1.17; 95% CI, 0.79-1.75, p=0.429).

CONCLUSIONS

Based on studies with mean follow-up ≥5 years, 31% of SCAs have recurrence. No evidence supporting higher recurrence risk of SCAs compared with other NFPA subtypes was found.