The Seroprevalence of Toxoplasma gondii in Chinese Population With Cancer: A Systematic Review and Meta-analysis

Toxoplasmosis is fatal in the immunocompromised individuals such as cancer patients with chemotherapy. Clinical toxoplasmosis in cancer patients is a great public health concern in China. We performed this meta-analysis to assess the seroprevalence and odds ratios (ORs) of Toxoplasma gondii in Chinese population with cancer compared with those without. A methodical literature search was conducted with the help of the PubMed, Web of Knowledge, Embase, Chinese Web of Knowledge, Wanfang, and Chongqing VIP database. Case-control studies published from their inception until April 2015, reporting the seroprevalence of T. gondii in Chinese population with cancer, were covered as well. The nonweighted prevalence, pooled random-effects estimates of ORs, and 95% confidence intervals (CIs) were all calculated. Nineteen studies including 4493 cases and 6797 controls were incorporated in the meta-analysis. The overall seroprevalence of T. gondii was higher in population with cancer compared with those without ((20.59% vs 6.31%, P < 0.001; OR 3.90, 95% CI 3.00–5.07). The OR of T. gondii in cancer patients is further subgrouped according to publication year, sample size, and diagnostic methods. The pooled OR estimates were 4.80 (95% CI 2.57–8.99) from 1991 to 1999, 4.96 (95% CI 3.03–8.12) during 2000 to 2005, and 2.94 (95% CI 2.46–3.50) during 2006 to 2015. The pooled OR estimates were 6.16 (95% CI 3.87–9.78) when the sample size was below 400, 5.37 (95% CI 3.84–7.53) when the sample size was between 400 and 500, and 2.58 (95% CI 2.17–3.07) when the sample size was above 500. The pooled OR estimates were 5.50 (95% CI 3.98–7.62) by using indirect hemagglutination assay method, and 3.15 (95% CI 2.67–3.72) by using enzyme-linked immunosorbent assay method. The meta-analysis study found Chinese population with cancer had higher seroprevalence rates of T. gondii compared with those without.