Meta-Analysis Suggests Association of L-myc EcoRI Polymorphism with Cancer Prognosis

The L- myc Eco RI polymorphism is a noncoding variation in the second intron of the L- myc gene, resulting in S and L alleles. Individuals carrying the S allele tend to have poor prognosis and increased risk of several tumor types, although controversial results have been reported. A meta-analysis of 36 studies on L- myc Eco RI genotyping, including 3563 patients with different types of cancer and 2953 controls, was performed. In lung cancer patients the S/S genotype was significantly associated with lymph node metastasis [odds ratio (OR), 2.8; 95% confidence interval (CI), 1.8–4.3], distant metastasis (OR, 4.7; 95% CI, 2.4–9.2), and stage (OR, 2.3; 95% CI, 1.2–4.4). No association was observed between the S/S genotype and cancer (OR, 1.1; 95% CI, 0.8–1.4). In patients with other cancers, the S/S genotype was significantly associated with tumor recurrence (OR, 2.8; 95% CI, 1.4–6.0), whereas no significant association was seen for the other prognostic parameters. When all types of cancer were examined together, the S/S genotype was associated with lymph node metastasis (OR, 2.3; 95% CI, 1.6–3.3), distant metastasis (OR, 2.9; 95% CI, 1.8–4.6), clinical stage (OR, 1.8; 95% CI, 1.2–2.9), and cancer risk (OR, 1.25; 95% CI, 1.07–1.45). The meta-analysis suggests that the L- myc Eco RI polymorphism is a marker of tumor prognosis in lung cancer and possibly in other types of cancer.