Prostate cancer (PCa) patients who drink at least one cup of coffee per day may experience a significantly decreased risk of PCa recurrence or progression after treatment or while on active surveillance, researchers reported online ahead of print in Cancer Causes and Control.
In a study of 630 men aged 35-74 diagnosed with PCa from 2002 to 2005, drinking one cup of coffee per day was associated with a 56% decreased risk of recurrence or progression compared with drinking one cup or fewer per week, in adjusted analyses. Drinking four or more cups per day and two to three cups per day was associated with a 59% and 28% decreased risk, respectively.
“For men diagnosed with prostate cancer who are already consuming coffee, we would suggest that they continue to drink coffee as it may reduce their risk of recurrence/progression,” lead investigator Janet Stanford, MD, told Renal & Urology News.
“For men who do not drink coffee, it is not possible to recommend that they start drinking coffee based on results from our observational study, especially as some of these men may have medical conditions that could be exacerbated by caffeine or coffee intake. The latter patients should consult with their physicians as to whether it would be okay for them to drink a cup of coffee a day.
This new findings appear to confirm earlier research showing a protective effect of coffee drinking in men. Therefore, the investigators say that while the field is waiting for a randomized, controlled trial of coffee consumption, urologists can proceed on the assumption that it can be beneficial for some men.
Dr. Stanford, Co-Head of the Program in Prostate Cancer Research at the Fred Hutchinson Cancer Research Center in Seattle, and her collaborators in the U.S. and Holland reviewed data from an earlier population-based, case-control study (Am J Epid 2008;168:250-260). Of the 630 men they included in their analysis, 61% drank at least one cup of coffee a day. Twelve percent drank four or more daily. More coffee was drunk by whites, men who were former or current smokers, and those who also consumed alcohol. Regular exercisers and tea drinkers had lower coffee consumption.
Of 140 PCa recurrence or progression events, 25 were fatal, 77 involved secondary treatment, and 28 involved rising PSA levels alone.
The team also evaluated tea drinking and found no significant difference in risk at various levels of consumption. However, the cohort had few regular tea drinkers, and the highest category of consumption was defined as one or more cups per day.
Earlier research had also uncovered a PCa-protective effect of coffee drinking, particularly related to the non-caffeine components of the beverage.
Although Dr. Stanford’s team did not examine dietary factors ranging from quantities of milk and sugar in the coffee to intake of fruits, vegetables, and supplements, “few such factors have consistently been associated with prostate cancer recurrence or progression.”