Tumor M2-pyruvate kinase as tumor marker in exocrine pancreatic cancer - A meta-analysis

Objectives: Tumor M2-pyruvate kinase, a tumor-associated dimeric form of enzyme pyruvate kinase, is commonly elevated in pancreatic cancers. This meta-analysis aimed to evaluate its diagnostic utility in comparison to carbohydrate antigen 19-9 (CA19-9) in pancreatic cancer. Methods: A literature search was conducted for entries from 1951 to 2006 using PubMed, Embase, Central, and SCI Expanded databases using M2 pyruvate kinase AND pancreatic cancer/s OR tumor/s as keywords. A total of 258 references were retrieved. Of these, 118 duplicates were removed and 132 references were excluded. All studies comparing TuM2-PK with CA19-9 in pancreatic cancer were included. Full text was obtained for 8 references of 7 included studies. Diagnostic odds ratio (DOR) and 95% confidence interval (CI) was calculated from the available specificity and sensitivity for each study and were pooled to give overall DOR and 95% Cl for TuM2-PK and CA19-9. Receiver operator characteristic curve was calculated to give overall specificity and sensitivity for TuM2-PK. Results: The diagnostic performance of TuM2-PK (DOR, 35; 95% CI, 19.7-62.3) was similar to those of CA19-9 (DOR, 44; 95% CI, 26.5-73.1). The overall specificity for TuM2-PK was 60% with corresponding sensitivity of 95%. Conclusion: Efficacy of TuM2-PK as a tumor marker is similar to that of CA19-9. Further trials are needed to use it alone or in combination with CA19-9 in patients with suspected pancreatic cancer.