Postoperative injections of 5-FU may reduce surgical failures and intraocular pressure at one year in the primary trabeculectomy group and high-risk group. Complications may be more common after 5-FU injections. The methodological quality of the trials was not high.
Systematic review 1
Low-quality evidence exists that mitomycin may be more effective in achieving long-term lower intraocular pressure than 5-Fluorouracil «Cabourne E, Clarke JC, Schlottmann PG ym. Mitomyci...»1
Systematic review 2
This update of a Cochrane review, first published in 2000, and updated in 2009 and 2014, assessed the effects of both intraoperative application and postoperative injections of 5-FU in eyes of people undergoing surgery for glaucoma at one year. Search methods: CENTRAL, Ovid MEDLINE, Ovid OLDMEDLINE, EMBASE, mRCT, ClinicalTrials.gov, and ICTRP by July 2013. RCTs of intraoperative application and postoperative 5-FU injections were compared with placebo or no treatment in trabeculectomy for glaucoma. Standard methodological procedures expected by The Cochrane Collaboration were used. Trial investigators were contacted for missing information.
The participants were divided into three separate subgroup populations (high risk of failure, combined surgery and primary trabeculectomy) and the interventions were divided into three subgroups of 5-FU injections (intraoperative, regular dose postoperative and low dose postoperative). Twelve trials, which randomised 1319 participants, were included in the review. As far as can be determined from the trial reports, the methodological quality of the trials was not high, including a high risk of detection bias in many. Of note, only one study reported low-dose postoperative 5-FU and this paper was at high risk of reporting bias. All studies were a minimum of one year long.
A significant reduction in surgical failure in the first year after trabeculectomy was detected in eyes at high risk of failure and those undergoing surgery for the first time receiving regular-dose 5-FU postoperative injections (RR 0.44, 95% confidence interval (CI) 0.29 to 0.68 and 0.21, 0.06 to 0.68, respectively). No surgical failures were detected in studies assessing combined surgery.
No difference was detected in the low-dose postoperative 5-FU injection group in patients undergoing primary trabeculectomy (RR 0.93, 95% CI 0.70 to 1.24). Peroperative 5-FU in patients undergoing primary trabeculectomy significantly reduced risk of failure (RR 0.67, 95% CI 0.51 to 0.88). This translates to a number needed to treat for an additional beneficial outcome of 4.1 for the high risk of failure patients, and 5.0 for primary trabeculectomy patients receiving postoperative 5-FU.
Intraocular pressure was also reduced in the primary trabeculectomy group receiving intraoperative 5-FU (mean difference (MD) -1.04, 95% CI -1.65 to -0.43) and regular-dose postoperative 5-FU (MD -4.67, 95% CI -6.60 to -2.73). No significant change occurred in the primary trabeculectomy group receiving low-dose postoperative 5-FU (MD -0.50, 95% CI -2.96 to 1.96). Intraocular pressure was particularly reduced in the high risk of failure population receiving regular-dose postoperative 5-FU (MD -16.30, 95% CI -18.63 to -13.97). No difference was detected in the combined surgery population receiving regular-dose postoperative 5-FU (MD -1.02, 95% CI -2.40 to 0.37).
Whilst no evidence was found of an increased risk of serious sight-threatening complications, other complications are more common after 5-FU injections. None of the trials reported on the participants' perspective of care.
Authors' conclusions: Postoperative injections of 5-FU are now rarely used as part of routine packages of postoperative care but are increasingly used on an ad hoc basis. The small but statistically significant reduction in surgical failures and intraocular pressure at one year in the primary trabeculectomy group and high-risk group must be weighed against the increased risk of complications and patient preference «Green E, Wilkins M, Bunce C ym. 5-Fluorouracil for...»2.