Thanks for posting your query.
Keloids are overgrowths of fibrous tissue or scars that can occur after an injury to the skin. Ear lobes are common sites due to piercing.It occur most frequently in individuals of African-American descent and in those with darker skin.During skin repair
forms at the site of the scar and keeps forming because it is not shut off resulting in keloid formation.
It can be successfully treated with injections of corticosteroid directly into scar. Radiation
,Silicone sheets etc can also be used. Larger Lumps like you have on your abdomen can also be removed by excision and surgery.
There are many options you can choose with help of your doctor to get rid of these scars, however you should avoid such scars in future by avoiding any trauma to the skin and compression pressure dressing.
Hope it helps.