Table 1. Basic characteristics of the included studies.
| Study/Country | Patients/samples | Methods | Primary Aim | Methylation site |
|---|---|---|---|---|
| Dauksa 2012 12/Germany | 26/blood | MSP, SIRPH | Study whether methylation changes in blood could provide a method for early detection of PDA | Promoter, CpG islands |
| Li 201213/China | 5/tissue | MSP | Investigate whether epigenetic modification via hypermethylation represents a mechanism for the inactivation of CDKN2A gene in PDA | Promoter, CpG islands |
| Tan 2007 14/Singapore | 2/blood | MSP | Detect whether serum methylation of CDKN2A is a marker for PDA | Promoter, CpG islands |
| Li 200715/USA | 57/blood, 9/tissue | MSP | Detect whether plasma DNA might be a useful surrogate in epigenetic alterations of PDA | Promoter, CpG islands |
| Matsubayashi 200616/USA | 11/PJ | MSP | Examine whether aberrantly methylated DNA in PJ is an approach for diagnosis of PDA | Promoter, CpG islands |
| Peng 200617/Japan | 56/tissue | MSP | Study whether accumulation of DNA methylation of multiple tumor-related genes is involved in multistage carcinogenesis of pancreas | Promoter, CpG islands |
| Liu 200518/USA | 16/tissue | MSP | Detect whether epigenetic changes in PENs vary in age, histopathologic type and metastasis | Promoter, CpG islands |
| Chan 200319/USA | 10/tissue | MSP | Determine whether methylation profile of PENs differs from carcinoid tumors | Promoter, CpG islands |
| Yan 200520/England | 42/PJ | MSP | Utilize molecular analysis to detect PDA in high-risk groups | Promoter, CpG islands |
| Klump 200321/Germany | 37/PJ | MSP | Determine a role for CDNK2A as a diagnostic marker in differentiation of benign and malignant pancreatic disease | Promoter, CpG islands |
| House 200322/USA | 48/tissue | MSP | Study whether methylation of TSG was an independent predictor of early PENs recurrence and OS following surgical resection | Promoter, CpG islands |
| Ohtsubo 200324/Japan | 60/tissue | MSP | Detest expression of CDKN2A protein and the clinicopathological parameters | Promoter, CpG islands |
| Fukushima 200325/USA | 33/tissue, 45/PJ | MSP | Examine whether CDKN2A in PJ can be a diagnostic approach for PDA | Promoter, CpG islands |
| Fukushima 200223/USA | 15/tissue | MSP | Examine whether CDKN2A can be an indicator of the potential malignancy of epithelial cells of the pancreas | Promoter, CpG islands |
PJ: pancreatic juice, tissue: pancreatic tissue, MSP: methylation-specific PCR, SIRPH: sNuPE with IP-RP-HPLC, PENs: pancreatic neuroendocrine neoplasm, TSG: tumor suppressor gene, OS: overall survival.