Cancer communicable in backwash

Factual Questions
1

Hello Dopers,

Let me get rid of some of my ignorance. I have a friend who is being treated successfully for Leukemia. I have twice drunk from his water bottle, which I am sure COULD have some of his backwash. Is it possible that I could drink some cancerous cells into my body or something along those lines? Is there any risk to me from doing this, even a slight risk?

Thanks.

2

There is no risk of contracting his leukemia this way. You’ll need to find other things to be nervous about.
Perhaps the drive over to see him is dangerous…

3

I wouldn’t expect so. I don’t think cancer is (generally) a communicable disease.

4

There is no risk to you of contracting his leukemia by sharing a water bottle.

There is a real risk here though, and that is of you exposing him to infectious agents that he is vulnerable to because of a compromised immune system.

So you’re fine, but you still shouldn’t share his water bottle.

5

Leukemia is a blood and bone marrow cancer, chances are almost none that he had any of that in his saliva, unless he was bleeding out the mouth. Even if you did swallow some of those cancer cells, they would have to pass through your digestive system and various membranes intact. The reason cancer is so dangerous to people who develop it, is that the body does not recognize that the cells are not part of their body and they are allowed to keep growing. Even if they somehow lodged into your body somewhere, your body would be able to recognize the cells and eliminate them.

6

Yes! I really hope you’re talking about sharing his water bottle prior to any chemo/radiation/transplant taking place. Giving him something as minor as a cold could kill him while his immune system is so mucked up.

7

Here’s something interesting:

Apparently they’ve discovered a communicable cancer in dogs, a line of dog cells (identical in all the victims) that is believed to be hundreds of years old. No such things is known in humans though. it says the only way humans have ever been known to transmit cancer is through organ transplants.

See also Canine transmissible venereal tumor - Wikipedia

8

Tasmanian Devils Spread Cancer by Biting
No one’s found a human version though.

9

Given the amount of research time and money we spend annually to try to figure out exactly how cancer is caused, I think the only reasonable answer is “we don’t really know”.

Furthermore, there are studies regarding the high incidence of spouses with cancer which could imply communicability, there are theories that it’s caused by viruses (virii?), etc.