Even though lipomas are generally benign, you should not ignore all lumps and bumps. People with fibromyalgia can still get cancer just like anyone else can. Get checked out by a doctor for any new lumps or bumps, especially if they look unusual or cause pain.
Lipomas are not associated with an increased risk of skin cancer. Many fibro patients are afraid of complaining too much, but you still owe to to yourself to get regular skin examinations.