Patients expressing low levels of either Piwi-like 2/Piwi-like 3 or of Piwi-like 2/Piwi-like 4 had a significantly increased risk of tumor-related death compared with patients with a high expression level of the Piwi-like mRNAs (RR = 2.10, 95% CI: 1.01–4.40; p = 0.048 and RR = 2.58, 95% CI: 1.26–5.29; p = 0.01, respectively; Table 2 ). Here, PIWIL4 is linked to neoplasm.