Cansema is a corrosive substance that is sometimes also referred to as a black salve. Due to its ability to act as a corrosive agent to the skin, some alternative medicine practitioners tout this substance as a possible cure for external cancers. Cansema and similar topical substances have been used to treat certain types of cancers and lesions for hundreds of years.
The idea in modern alternative medicine is that cansema causes cell death, or necrosis, by burning away the unhealthy tissue. This results in the formation of a scab, or an eschar, and for this reason substances like cansema are often referred to as escharotics. The scab usually lasts for about a week, after which time the dried scab will usually be dislodged.
After the scab falls off, the underlying skin might be raw and irritated. Alternative medicine practitioners suggest keeping the area clean and applying a soothing agent. Complete healing is expected to occur within a few weeks. There is a chance that this process will leave some scarring.
Proponents of escharotics claim that these substances are totally safe and effective ways to get rid of skin cancers and lesions. Some even claim that these agents can specifically recognize cancerous cells and eliminate them. Their view is that as long as one chooses a skilled alternative medicine practitioner, this process is entirely safe.
The majority of Western medicine doctors does not agree with this and advise people against using these agents for any type of lesion. The greatest concern is that patients using these treatments will completely avoid, or put off, getting Western treatment. This can result in worsening, or spreading, of the cancer.
Western doctors are also concerned that even if cansema does effectively kill surface cancer cells, there is no way of knowing how many cancer cells remain in the area. When a doctor or surgeon removes a cancerous growth, they will usually remove a large amount of surrounding normal tissue. The amount of normal tissue that should be removed may be judged by the use of dyes or specific products that recognize cancer cells, or it may be judged based on the surgeon’s experience with such cancers. Cansema treatment, on the other hand, appears to be a very random process of tissue removal.
Finally, cansema treatment can be damaging to the skin if applied too heavily or for too long of a time. The corrosive nature of this substance may lead to serious burns or deep scarring. Several cases have been documented where people have needed extensive plastic surgery following cansema treatment by an unskilled practitioner.