Okay, so imagine you have a little pouch made of clay or metal that you fill with hot coals to keep you warm when it's cold outside. That little pouch is called a kangri and it's commonly used in some parts of the world like Kashmir.
Now, sometimes people who use kangris a lot can get something called "kangri cancer." This might sound scary, but it just means they might get a kind of skin cancer on the part of their body where they hold the kangri, like their stomach or chest.
This happens because the kangri can get really hot and if it's held too close to the skin for too long, it can cause damage and make the skin more likely to get cancer. That's why it's important for people who use kangris to be careful and not hold them too close to their skin or for too long.
But don't worry, kangri cancer is still pretty rare and most people who use kangris will never have to worry about it as long as they use them safely.