Screening for any disease, including prostate cancer remains imperfect. One study, the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, was a National Cancer Institute (NCI) sponsored study that took place between 1993-2001. The goal of the trial was to investigate the impact cancer screening had on dying from these four common tumor types. There were 76,693 men evaluated in the prostate cancer portion of the study.
While some aspects of this randomized trial remain controversial, including the impact that screening had on dying from prostate cancer, it remains a rich prospective dataset for further analysis, as it is one of the largest longitudinal studies ever conducted of men with prostate cancer.
In the “intervention” arm of the PLCO Screening Trial in which men were randomized to be screened for prostate cancer with annual prostate specific antigen (PSA) blood tests and digital prostate exams, there was still an unfortunate set of men who died from prostate cancer. Because the goal of the trial was to determine the prostate cancer mortality differences between the two arms, an understanding of who died and how they died is extremely important.
In a study led by Weill Cornell Medicine’s Dr. Chris Barbieri, we examined how men died of prostate cancer. Dr. Sameer Mittal presented the results of the research at an oral podium presentation yesterday at the 2016 American Urological Association annual meeting, with full results simultaneously published in European Urology.
Of 38,340 men in the screening arm, 151 died of prostate cancer. After graphing their oncologic courses of diagnosis and treatment, we noted a few interesting trends. The most prominent were as follows:
- More than 50% of the men who died (81 men) either were never screened before this test or had their first PSA test result that was positive. These men were older and had higher median PSA (13.7). It’s possible that if these men were actually screened and or screened earlier and treated, their deaths from prostate cancer could have been prevented.
- A subgroup of men who died despite screening were young and had a low median PSA (2.0). Surprisingly, they died within approximately 1.5 years of diagnosis. To put this in perspective, we expect an average man diagnosed with metastatic prostate cancer to live for 5 years, so this is quite unusual. We know that some subsets of prostate cancer do not secrete high levels of PSA and this is an area that needs more research in order to prevent further deaths. We don’t know for sure if these men had neuroendocrine prostate cancer (NEPC), but their rapid disease course seems consistent with this aggressive prostate cancer sub-type.
Despite what some may believe, some men do die of prostate cancer. We continue to research why this is the case in order to prevent further death and suffering from this common disease. These study insights underscore the importance of developing diagnostic biomarkers to better detect aggressive prostate cancers and to best predict the way the cancer will respond to various treatments.