Tobacco smoking and long-lasting symptoms from the bowel and the anal-sphincter region after radiotherapy for prostate cancer

Abstract Background and purpose Tobacco smoking can cause vascular injury, tissue hypoxia and fibrosis as can ionizing radiation. However, we do not know if tobacco smoking increases the risk of long-term side effects after radiotherapy for prostate cancer. Methods We identified 985 men treated with radiotherapy for prostate cancer between 1993 and 2006. In 2008, long-lasting symptoms appearing after radiotherapy for prostate cancer were assessed through a study-specific questionnaire as were smoking habits and demographic factors of all these men. In the questionnaire the prostate-cancer survivors were asked to report symptom occurrence the previous six months. Results We obtained information on tobacco smoking from 836 of the 985 prostate-cancer survivors with a median time to follow-up of six years (range 2–14 years). The prevalence ratio of defecation urgency among current smokers compared to never smokers was 1.6 (95% CI 1.2–2.2). Corresponding prevalence ratio for diarrhea was 2.8 (95% CI 1.2–6.5), the sensation of bowel not completely emptied after defecation 2.1 (95% CI 1.3–3.3) and for sudden emptying of all stools into clothing without forewarning 4.7 (95% CI 2.3–9.7). Conclusion Tobacco smoking among prostate-cancer survivors treated with radiotherapy increases the risk of certain long-lasting symptoms from the bowel and anal-sphincter region.