• linkedin
  • Increase Font
  • Sharebar

    Immune content linked to aggressive PCa outcomes

    The level of immune response in prostate cancer may predict a patient’s response to radiation therapy, risk of disease recurrence, and survival outcomes, according to results of a recent analysis of prostate tumors presented at the American Society for Radiation Oncology (ASTRO) annual meeting in San Diego.

    “There's lots of work being done currently about the relationship between radiation and the immunotherapy,” said researcher Shuang (George) Zhao, MD, of the University of Michigan, Ann Arbor.

    “This just provides another line of evidence that there's some sort of interaction and we really should be focusing on this,” added Dr. Zhao, who worked on the study with Felix Y. Feng, MD, and co-authors.

    In a related finding, the tumors Dr. Zhao and co-authors evaluated had low expression of PD-L1, but high expression of PD-L2, a finding that could have important implications for the development of checkpoint inhibitors that target these ligands.

    PD-L1 is the target of several checkpoint inhibitors that are approved by the FDA for other cancer types, including melanoma and non-small cell lung cancer.

    Also see: Antiandrogen’s role may extend to non-metastatic CRPC

    “PD-L2 seems to come out in prostate cancer as a particularly important checkpoint molecule, much more so than PD-L1,” Dr. Zhao said in an interview with Urology Times. “That (finding) is definitely really interesting, because there's so much focus on PD-L1, but there are all of these different immune checkpoint molecules, and it may not be that every single tumor type is as dependent on PD-L1 as, say, in lung cancer.”

    The goal of the investigations was to help better define the “immune landscape” of localized prostate cancer, according to the researchers, who examined a total of 9,393 tumor samples from men who underwent a radical prostatectomy, including 1,567 samples obtained retrospectively and 7,826 obtained prospectively.

    They measured immune content in the tumor samples using high-throughput genome-wide expression analysis, and developed an immune content score that estimates the overall immune infiltrate in the samples.

    The authors grouped the samples into clusters defined by level of immune expression, and found that a higher immune content score was associated with worse outcomes, including overall survival (hazard ratio [HR]=1.3, p=.006), prostate cancer-specific survival (HR=1.5, p=.0003), freedom from disease progression (HR=1.3, p=.0002), and freedom from distant metastases (HR=1.3, p=.0006), according to data presented at ASTRO, which represented analysis of the retrospectively obtained samples only.

    Next: Immune content score was prognostic primarily in patients that received post-op radiation

    Andrew Bowser
    Andrew Bowser is a medical writer based in Brooklyn, New York.


    You must be signed in to leave a comment. Registering is fast and free!

    All comments must follow the ModernMedicine Network community rules and terms of use, and will be moderated. ModernMedicine reserves the right to use the comments we receive, in whole or in part,in any medium. See also the Terms of Use, Privacy Policy and Community FAQ.

    • No comments available