Lipomas are benign lumps of fat that grow under a dog's skin. The dogs most prone to lipomas are overweight females. Itching is not a normal symptom of lipoma.
Lipomas are often located on the belly or inner thighs of dogs, which can rub onto the ground. This may irritate the dog and cause severe itching. When inflamed or irritated, the lipomas will feel firmer than before.
A dog may get parasites, ringworm, or a skin infection unrelated to the lipoma, but start scratching in that area. Scratching the lipoma open can result in dangerous infections for the dog.
If it is decided to remove the lipoma surgically, the dog will often scratch or chew at the incision. The healing skin will be itchy, so the dog will need to wear a collar to be sure it does not open the incision.