This study analyzed the association between inflammation and aggressive prostate cancer.

Inflammation may play a role in the development and progression of many cancers, including prostate cancer. Many pro-inflammatory cytokines (proteins that mediate inflammation) are associated with metastatic prostate cancer (cancer that has spread) including IL-1, IL-6 and TNF-α. There are also genetic links between inflammation and prostate cancer: MSR1 is a gene associated with inflammation that has been shown in some studies to be associated with susceptibility to prostate cancer.

While this evidence, taken together, makes a strong case for the link between inflammation and prostate cancer, more direct evidence is needed to prove this theory. This study analyzed the association between tumor inflammation, adverse results of microscopic examination of tumor samples and biochemical recurrence (high prostate specific antigen levels following treatment).

This study analyzed the records of 287 men who underwent radical prostatectomy (surgical removal of the prostate) without preoperative androgen deprivation (reduction of male hormones) or radiotherapy. Average follow-up was 80 months.

17% of men had no inflammation, while 53% of patients had mild inflammation and 30% had marked inflammation. Men with more inflammation had 2.95 times the risk of capsular penetration (penetration of tumor cells through the muscular band surrounding the prostate), and 6.21 times the risk of seminal vesicle invasion (spread of the tumor to the seminal vesicle glands attached to the prostate). Men with more inflammation also had 3.67 times the risk of having positive margins (presence of cancer cells in the margin of healthy tissue that is removed along with the tumor during surgery).

Biochemical recurrence occurred among 44% of the patients. This occurred in 24% of the men with no inflammation, 46% of those with mild inflammation and 51% of those with marked inflammation. Overall, increasing inflammation was associated with a trend towards increased biochemical recurrence, with those experiencing marked inflammation being more than twice as likely to experience biochemical recurrence as those without inflammation.

The authors concluded that inflammation within prostate cancer was associated with advanced disease following radical prostatectomy. However, it is as yet unclear whether inflammation is the cause of, or as a result of advancing prostate cancer.