Deep lipoma on low r side of back/pelvis area. Grown in size about an avocado seed but wider more pain stemming from lump to right buttock down leg.?

May not be related. Lipomas on the lower back and upper hip are common. If the size flutuates often and/or is tender to the touch you may want to see your md to get an ultrasound. Pain in the buttock down the leg is usually from an irritated nerve in the low back. These nerves are deeper than typical lipomas.