Among the 12 studies included, 6 studies [18, 20–24] with a total of 362 patients analyzed the association between DAPK methylation and patients’ 5-year survival rates, mainly in patients with thymic MALT lymphoma [21], follicular lymphoma [23], and DLBCL [18, 20, 22, 24]. Here, DAPK1 is linked to MALT lymphoma.