Increased serum amyloid A as potential diagnostic marker for lung cancer: a meta-analysis based on nine studies

Previous studies have disclosed that serum amyloid A (SAA) is likely involved in the lung cancer pathogenesis and progression. We performed a systematic evaluation and meta-analysis to disclose the correlation between the expression of SAA and lung cancer and to evaluate its value for lung cancer diagnosis.

We searched the relevant articles from the databases of Medline, Embase, Cochrance Library and Web of Science and calculated the standardized mean difference (SMD) with 95 % confidence interval (CI) to assess the expression difference of SAA between lung cancer and normal patients. Moreover, we counted the positive rate, sensitivity and specificity and drew a summary receiver operating characteristic curve (SROC) to evaluate the diagnostic value of SAA for lung cancer.

A total of nine studies with 1392 individuals were included in this analysis. The results showed an increased SAA was correlated with the incidence of lung cancer (P < 0.001), especially with the lung squamous cell carcinoma (LSCC) (p = 0.012). The overall sensitivity and specificity of SAA for discerning lung cancer was 0.59 (95 % CI: 0.54-0.63) and 0.92 (95 % CI: 0.88-0.95), respectively. The area under the SROC curve was 0.9066 (SE = 0.0437).

Increased SAA in lung cancer was intimately correlated with the development and progression of lung cancer. A higher specificity of SAA suggested that it should be a significant biomarker for discerning lung cancer from normal individuals, especially for LSCC (p = 0.012).