DNA Ploidy as a Potential Adjunct Prognostic Marker of Low-Risk Prostate Cancer Progression after Radical Prostatectomy - Beyond the Abstract

Timely delivery of salvage treatments after prostatectomy is related to improved outcomes. A recent study suggests that giving salvage radiotherapy when PSA levels of less than 0.25 ng/ml, was associated with increased long term survival vs. when radiation was given when PSA was above 0.25 ng/ml.1 Additional biomarker is needed to guide timely and personalized decisions for multimodal treatments at the time of prostatectomy.

Our study investigates the potential of DNA ploidy as a prognostic marker for biochemical recurrence (BCR) in low-risk prostate cancer patients after radical prostatectomy. The traditional markers for BCR, such as Gleason score (GS) and stage (pT), including post-prostatectomy prostate-specific antigen kinetics, have limitations, and there's a need for more immediate and objective prognostic markers. DNA ploidy analysis, which assesses large-scale genomic alterations, has shown promise in other cancers.

Our study involves 97 patients with low-risk cancer who underwent prostatectomy. DNA ploidy is measured using image cytometry, to generate the Ploidy Score (PS). The results reveal that DNA ploidy, especially aneuploidy (abnormal DNA content), correlates with BCR. Patients with higher PS values are at a greater risk of recurrence, even in the low-risk group. Furthermore, PS correlates to BCR with highest risk of mortality.

Interestingly, DNA ploidy's predictive power remains significant even when compared to expert pathologist assessments of Gleason Grade Groups and clinical parameters like pathological T stage (pT). Combining DNA ploidy with Gleason assessment further improves risk stratification.

The study underscores the potential of DNA ploidy as an independent prognostic marker for BCR in low-risk prostate cancer. Incorporating DNA ploidy assessment into pathology reports could refine clinical management, helping identify patients who may require more aggressive treatment strategies upfront or closer follow-up. However, the study acknowledges the need for larger cohorts to strengthen the findings. Overall, DNA ploidy analysis could enhance risk stratification and personalized treatment decisions in low-risk prostate cancer cases, and its prognostic significance should be further tested in intermediate and high risk patients.

Written by: Miha Pukl, MD, PhD, FEBU, Department of Urology, GH Celje, Celje, Slovenia

  1. Derya Tilki, Ming-Hui Chen, Jing Wu, Hartwig Huland, Markus Graefen, Osama Mohamad, Janet E. Cowan, Felix Y. Feng, Peter R. Carroll, and Anthony V. D'Amico. Prostate-Specific Antigen Level at the Time of Salvage Therapy After Radical Prostatectomy for Prostate Cancer and the Risk of Death. Journal of Clinical Oncology 2023 41:13, 2428-2435
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