In two-thirds of the cases with mixed CTC populations or ICC-PSA-negative-CTC (66%, 8/12), secondary cancer or metastases were diagnosed within 1-to-12 years after prostate cancer diagnosis, and included bladder, bowel, skin, Non-Hodgkin's-Lymphoma, thyroid, tongue cancer, and lymph node involvement (Table 1). Here, KLK3 is linked to tongue cancer.