Surgical outcomes of medically failed prolactinomas: a systematic review and meta-analysis

Purpose In Prolactinomas, surgery or radiation are reserved for DA failure due to tumor resistance, intolerance to medication-induced side-effects, or patient preference. This systematic review and meta-analysis summarizes the currently available literature regarding the effectiveness of surgery to treat prolactinomas in patients who have failed DA therapy. Method A literature search was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for studies that reported outcomes of medically resistant and intolerant prolactinoma treated surgically. Results 10 articles (Total N = 816, Surgery N = 657) met the inclusion criteria. 38% of patients who underwent surgery following DA failure achieved remission without need for further treatment (p < 0.001, I-2 = 67.09%) with a median follow-up of 49.2 +/- 40 months. 62% achieved remission with multimodal treatment (p < 0.001, I-2 = 93.28%) with a median follow-up of 53 +/- 39.8 months. 16% of cases demonstrated recurrence after early remission (p = 0.02, I-2 = 62.91%) with recurrence occurring on average at 27 +/- 9 months. Overall, 46% of patients required reinstitution of postoperative DA therapy at last follow up (p < 0.001, I-2 = 82.57%). Subgroup analysis of macroprolactinoma and microprolactinoma has demonstrated that there is no statistical significance in achieving long-term remission with surgery stand-alone in macroprolactinoma group (p = 0.49) although 43% of patients were able to achieve remission with multimodal therapy at last follow-up in the same group (p < 0.001, I-2 = 86.34%). Conclusions This systematic review and meta-analysis revealed 38% of operated patients achieved remission, while 62% achieved remission when additional modes of therapy were implemented. Therefore, although surgery has not been initial therapeutic choice for prolactinoma, it plays a significant role in medically failed prolactinoma care.