Effectiveness of palliative photodynamic therapy for unresectable biliary cancer. Systematic review and meta-analysis

Abstract

A systematic review and meta-analysis was aimed to assess the effectiveness of palliative photodynamic therapy for unresectable malignant tumors of the biliary system in order to justify the feasibility of including photodynamic therapy (PDT) in the complex treatment of this category of patients. Publications in the databases PubMed Central, the bibliographic database of scientifi citations of the RSCI, and the Cochrane library were considered. Heterogeneity was assessed graphically using forest plots and statistically using tau2 and I2 statistics. A meta-analysis of 5-year survival revealed a statistically signifiantly longer pooled estimate of the survival period in groups where PDT was used – 339±161 days (95% CI 25-710; p < 0.001) compared to groups where PDT was not used – 83±16 days (95% CI 33-100; p < 0.001). Heterogeneity among studies was found to be statistically insignifiant (I2 = 29%, p = 0.23). A meta-analysis of the risk difference for adverse events revealed a statistically signifiantly lower risk (-0.2306; 95% CI -0.3917-0.0696; p = 0.005) of adverse events after PDT compared with the comparison group. Heterogeneity among studies was found to be statistically insignifiant (I2 = 0%, p = 0.35). There were no signifiant publication biases in either meta-analysis. The presented meta-analysis demonstrated that PDT may be the method of choice in the palliative complex treatment of patients with unresectable cholangicarcinomas, increasing the ˝ve-year survival of patients along with the absence of increased risks of postoperative complications in comparison with other methods of palliative surgical treatment.