Sex and Cancer: Questions for Your Doctor Questions to ask: How long will these changes last? What can I do about them? Is it OK to have sex during treatment? Dealing with Erectile Dysfunction Erectile dysfunction is when a man is not able to achieve or maintain an erection sufficient for his sexual needs. It's often a side effect of the treatments for prostate cancer. Some men have chronic, complete erectile dysfunction, called impotence. Others have partial or brief erections. Sexuality Issues for Women Being Treated for Cancer Treatment for cancer can cause many changes that may affect your sexuality. It can also change the physical or emotional closeness you share with another person. Different treatments can cause different physical and psychological changes that can affect how you feel, look, and function. These changes may be temporary, or they may last a long time.