KLK3 and Familial prostate cancer: A trend of larger FSC scores was observed in prostate cancer patients in the training cohort, representing more common short fragments in cancer samples than in non-cancer samples, while there appeared to be some non-cancer samples with PSA ≥ 4 ng/mL which exhibited increased FSC scores when compared to those with PSA < 4 ng/mL (Fig. 1B and Figure S1).