Among the 259 patients without cancer progression, 55 (21.2%) showed no detectable methylated GCM2 in their plasma across all three PCR replicates, and 200 (77.2%) had no detectable methylated TMEM240. In contrast, among the 66 patients with recurrence or metastasis, only 4 (6.0%) had no detectable methylation of either GCM2 or TMEM240 in all three replicates. Here, GCM2 is linked to cancer.