Skin cancer usually creates an area on the skin that is discolored and raised. When playing with your cat or cuddling up with it, take the time to look over its body for areas of discolored skin. Also look for areas where the cat's fur is out of place, perhaps due to a growth on the skin underneath. If you find an abnormal area, have it looked at by a veterinarian. Cats get lumps on their skin for a variety of reasons, and skin cancer is only one of them. Your veterinarian will be able to assess whether any lumps you find are a problem or not. Because cats are covered in so much fur, its also important to feel your cat's body for signs of skin cancer. Feel for lumps and bumps on the skin in areas that are covered with fur and areas that are less covered. While skin cancer is often related to sun exposure, and thus occurs in areas with less fur, there are some kinds that are not related to sun exposure at all. Happily, cats are less likely than other animals to get skin cancer that is not UV triggered, such as mast cell tumors. Squamous Cell Carcinoma (SCC) most commonly affects white noses, eyelids, and ears. This is a direct result of UV exposure to thin-furred skin that lacks pigment. A sun-loving white cat is the most common kind of cat to develop SCC, so you should regularly look for signs of this disease on white cats. Indeed, if the cat has one black ear and one white, the white ear is much more likely to be affected by SCC. It is true that some signs related to skin cancer should spark your immediate concern, such as rapid growth, redness, or ulceration. However, there is no guarantee a small, slow-growing lump is harmless or harmful. This is why it is important to have all lumps assessed by a veterinarian.  Some aggressive tumors are great mimics, and take on the characteristics of innocent lumps, such as being superficial or slow growing. However, at some point in the future, they may become aggressive. It is difficult to distinguish a harmless skin lump from a sinister one, just by looking at it...

TL;DR in Indonesian:
Cari tonjolan atau perubahan warna. Rasakan benjolan di badan kucing. Periksa dengan lebih saksama untuk kucing berbulu putih. Bawa kucing ke dokter hewan supaya semua benjolannya diperiksa.