Electronic cigarettes (e cigarettes) are sometimes called e cigs, vapes, vape pens, and electronic nicotine delivery systems (ENDS). E cigarettes come in many shapes and sizes. Most e cigarettes contain nicotine. Get the facts about e cigarettes, E cigarettes are likely to cause cancer, including in the lungs and mouth, according to a sweeping review of scientific evidence that challenges their positioning as a safer alternative to smoking. There is Breast Cancer & E Cigarettes: Is Vaping a Safer Alternative to Smoking? Maurer Foundation Vaping can cause cancer, say researchers but still isn't as damaging as smoking cigarettes. More than 5.5 million Britons currently use e cigarettes, which have long been viewed as a safer alternative