Our gene prevalences for p16, MGMT, DAPK, and RASSF1A methylation in serum are very similar to that observed by Fujiwara et al (2005) in their study of serum from all stages of NSCLC and in our previous study of lung cancer survivors that examined free DNA recovered from plasma (Belinsky et al, 2005). The gene discussed is MGMT; the disease is lung cancer.