MADRID (EUROPA PRESS).- Smokers have a lower risk of developing prostate cancer, but a higher risk of dying from the disease, according to a large population study led by the University of Lund (Sweden).
In their work, published in the scientific journal ‘European Urology.’, the researchers followed more than 350,000 people for several decades to obtain these results.
Smokers have been shown to have an increased risk of developing various types of cancer, but there have been relatively few studies that have specifically investigated prostate cancer and included clinical information on prostate cancer. Therefore, this study may contribute to a more complete picture of the association between smoking and the risk of disease and death from prostate cancer.
The researchers used five Swedish population-based studies with self-reported information on men’s smoking. In all, more than 350,000 men were included in the study starting in 1974. They were then followed over the years using various national registries.
The Swedish National Prostate Cancer Registry provided data on tumor type at diagnosis, cause of detection, through symptoms or through a PSA test without nearby symptoms (asymptomatic PSA test), and treatment. During the period covered by the research, 24,731 of the participants developed prostate cancer and 4,322 died from the disease.
Among other things, the researchers found that, during the period of time that PSA tests have been available as part of routine health care check-ups, smokers have generally had a lower risk of prostate cancer . This is true only for localized prostate cancer, which is the form most often detected by an asymptomatic PSA test.
“A likely explanation for the lower risk of prostate cancer in smokers is that they may be less likely to have an asymptomatic PSA test. On the other hand, smokers have a higher risk of dying of prostate cancer, something we observed regardless of stage of the tumor at diagnosis, so this refers to all forms of prostate cancer, from low-risk to metastatic,” says Sylvia Jochems, MD, first author of the study.
The risk was 20 percent higher among smokers than among men who had never smoked. The risk increased even more if the smokers were also overweight (BMI 25-30) or obese (BMI greater than 30). The researchers say it is now important to identify why smokers have a worse prognosis once they have developed prostate cancer.
“We need to know more about whether it is smoking or other risk factors, such as sociodemographics, that cause this association. Another important question is whether the prognosis could be improved by stopping smoking after diagnosis of prostate cancer,” concludes Tanja Stocks, associate professor at Lund University and last author of the study.