Treatment of non-functioning pituitary adenoma with cabergoline: a systematic review and meta-analysis

Purpose: To make a systematic review and meta-analysis of studies evaluating the effect of cabergoline (CBG) in the treatment of non-functioning pituitary adenomas (NFPAs).

Methods: The primary outcome was tumor shrinkage, using as cut-off a reduction of at least 20% of the NFPA size from baseline. The secondary outcomes were prevention of tumor progression, clinically required additional interventions and adverse events (AE). Search strategies were applied to MEDLINE, EMBASE, LILACS and CENTRAL. Independent reviewers assessed the study eligibility, extracted data, and evaluated risk of bias. Random meta-analysis for the proportion of tumor shrinkage, prevention of tumor progression, clinically required additional interventions and frequency of AE were conducted.

Results: Five studies were included. The meta-analysis of proportion was 19% for tumor shrinkage (95% CI 8-38%, 4 studies, 108 participants), 50% for prevention of tumor progression (95% CI 35-64%, 5 studies, 187 participants), 14% for clinically required additional interventions (95% CI 6-30%, 4 studies, 128 participants) and 2% for adverse events (95% CI 1-6%, 3 studies, 157 participants).

Conclusions: Effect of CBG to promote tumor shrinkage in NFPAs was low, while prevention of tumor progression after surgery was seen in half of the cases, with a low frequency of adverse events.

Systematic review registration: PROSPERO CRD42020206778.