Clinical Edge

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Low Natural Killer Cell Activity Increases PCa Risk in Veteran Men Undergoing Biopsy

Key clinical point: Men with a low natural killer cell activity (NKA) value had 5-times higher odds of prostate cancer (PC) at biopsy.

Major finding: The odds ratio of low NKA for the detection of PC was 4.89, with a ROC area under the curve of 0.79 in all participants and increasing to 0.83 and 0.85 for the detection of PC and high-grade PC, respectively, among men with a normal DRE.

Study details: Differences were analyzed in NK cells from 94 men undergoing prostate biopsy to determine whether NK cells could predict for a positive biopsy.


Vidal AC, et al. Cancer Epidemiol. 2019 Aug 1;62:101578. doi: 10.1016/j.canep.2019.101578.


Identification of prostate cancer via biopsy is standard for patients with an elevated PSA; however, challenges continue regarding exactly who to biopsy and when to re-biopsy patients at high risk with previous negative results. Information to better inform biopsy strategies and biopsy accuracy is needed. Advances in understanding the relationship between the immune system and cancer makes evaluation of natural killer (NK) cell activity in prostate biopsies an important step. The mixed findings in the accompanying study of the significant association between low NK activity and prostate cancer but low sensitivity make further evaluation of NK activity important but challenging. —Mark A. Klein, MD