Surprisingly, Smokers Have a Lower Risk of Developing Prostate Cancer

Researchers have discovered that smokers have a reduced chance of acquiring prostate cancer but an increased risk of dying from the disease.

Smoking worsens the prognosis for men with prostate cancer

According to a large population study led by Lund University in Sweden, smokers had a decreased chance of acquiring prostate cancer but a greater risk of dying from the disease. The researchers tracked over 350 000 patients over several decades, and the findings have recently been published in European Urology.

Although it is commonly established that smokers have an increased risk of developing various cancers, there have been relatively few studies that have specifically analyzed prostate cancer and included clinical information about the cancer.

The extensive study may now help to provide a more full picture of the link between smoking and the risk of disease and death from prostate cancer. The researchers utilized self-reported data on men’s smoking habits from five Swedish population studies. From 1974 until the present, about 350 000 males were included in the study. They were then followed over the years using several national registers. The National Prostate Cancer Registry provided data on tumor type at diagnosis, cause of detection (by symptoms or a PSA test without symptoms) and treatment. During the study period, 24 731 individuals acquired prostate cancer, and 4 322 died as a consequence of the disease.

Among other things, the researchers found that over the period of time that PSA testing has been available as part of routine health check-ups in health care, smokers overall have had a reduced 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 probable explanation for the lower risk of prostate cancer in smokers is that they may be less likely to take an asymptomatic PSA test. On the other hand, smokers have a higher risk of dying from prostate cancer, which was something we observed regardless of tumor stage at diagnosis, so this means all forms of prostate cancer, from low risk to metastatic,” says Sylvia Jochems, Ph.D. and first author of the study.

The risk was about 20% higher among smokers than among men who had never smoked. The risk increased further if smokers were also overweight (BMI 25-30) or obese (BMI over 30). The researchers say it is now important to identify the reason why smokers have a poorer prognosis once they have developed prostate cancer.

“We need to understand more about whether it is smoking or other risk factors, such as socio-demographic factors, that cause this association. Another important question is whether prognosis could be improved by stopping smoking after a prostate cancer diagnosis,” concludes Tanja Stocks, Associate Professor at Lund University and last author of the study.

Reference: “Smoking and Risk of Prostate Cancer and Prostate Cancer Death: A Pooled Study” by Sylvia H.J. Jochemsa, Josef Fritz, Christel Häggström, Bengt Järvholm, Pär Stattin and Tanja Stocks, 4 May 2022, European Urology.
DOI: 10.1016/j.eururo.2022.03.033