Do cancer patients have bad odor? Only a few cancer patients, such as those with long-term unhealed ulcers or sinus tracts with secondary bacterial infections, may have bad odor, so cancer patients, especially early stage cancer patients, have the same odor as normal people. Of course, if you don’t pay attention to hygiene, even normal people will have bad odor, let alone cancer patients. Therefore, you can’t judge whether you are a cancer patient by whether you have bad odor, and it doesn’t mean that all cancer patients have bad odor, everyone’s situation is different, so we need to analyze each case. For advanced cancer patients, due to the necrosis of the tumor, there may be some odor on the body, but in most cases, the odor is not obvious. Except for the combination of other infections or necrosis as mentioned earlier, the odor may be strange or unbearable because of the bacterial decomposition of necrotic material.