Medical expulsive therapy (MET) with the alpha blocker tamsulosin improves passage of large distal ureteral stones, researchers in China concluded.
The finding is based on a double-blind, placebo-controlled study that included 3296 patients with distal ureteral stones. Patients were randomly assigned to receive tamsulosin (0.4 mg) or placebo for 4 weeks. Overall, tamsulosin-treated patients had a significantly higher stone expulsion rate than placebo recipients (86% vs 79%). Among patients with stones larger than 5 mm in maximum diameter, the stone expulsion rate was 87% in the tamsulosin arm compared with 75% among placebo recipients, a significant between-group difference, Zhangqun Ye, MD, of Huazhong University of Science and Technology, Wuhan, China, and colleagues reported online in European Urology. The investigators found no significant difference between tamsulosin and placebo among patients with 5 mm or smaller stones (88% vs 87%). The incidence of adverse events were similar between the groups.
In addition, among patients with stones larger than 5 mm, the average expulsion time was significantly shorter in the tamsulosin-treated patients compared with the placebo group (152.5 vs 299.5 hours).
“We demonstrated that the use of tamsulosin was safe and clinically effective in patients with distal ureteral stones and renal colic,” the investigators wrote. “A subgroup analysis identified a specific clinical benefit of tamsulosin for expulsion of distal ureteral stones >5 mm. Our findings add to the evidence of tamsulosin as a promising and useful treatment for large distal ureteral stones.”
Investigators used computed tomography (CT) to determine distal ureteral stone location and size and to confirm stone expulsion. Patients underwent weekly CT scans over the 28-day surveillance period of the trial.
In an accompanying editorial, Philipp Dahm, MD, and Shyam Sukumar, MD, of Minneapolis VA Medical Center and the University of Minnesota in Minneapolis, and John Hollingsworth, MD, of the University of Michigan Medical School in Ann Arbor, said the results of the trial “need to be placed in the context of the entire body of evidence from other well-designed, placebo-controlled trials … However, it is likely that such meta-analyses will confirm that if stone size and location are known, treatment is effective in patients with larger stones in the lower ureter. For this question, the verdict is in and no further trials are required. In these patients, the benefits appear to clearly outweigh the harms.”
They pointed out that in many countries, CT imaging of patients presenting with typical symptoms of renal colic is not the norm. “In that setting, the trade-offs for MET may be less clear cut, given that many stones presenting as renal colic are small in size,” they wrote.
Ye Z, Zeng G, Yang H, et al. Efficacy and safety of tamsulosin in medical expulsive therapy for distal ureteral stones with renal colic: A multicenter, randomized, double-blind, placebo-controlled trial. Eur Urol 2017; published online ahead of print.
Dahm P, Sukumar S, Hollingsworth JM. Medical expulsive therapy for distal ureteral stones: The verdict is in. Eur Urol 2017; published online ahead of print.