Hello, Welcome to Health Care Magic. Thanks for writing. I am Dr.Saddiq-ul-Abidin. I have read your question completely, i understand your concern and will try to help you in best way possible. According to your history and description of the mass there can be a few possibilities which i will mention here and I will also give you some suggestions to follow this issue. Possibilities are: 1)Lipoma: These are common fat tissue tumors which are really common and are benign they can be diagnoses on biopsy and can be surgically removed , even if they are not removed they are safe. This possibility is what I think you most probably have because you swelling doesn t move and doesn t pain. 2) Rib tumour: Rib tumorus can present as hard mass but usually in their drown they do cause symptoms and they don t get real large before taking attention from the patient. This is remote possibility but mentioned here to let you know what else can me there other than a lipoma. 3) Liver mass: On the right upper side of abdomen liver mass can be there, usually a large liver mass with no pain and symptoms is a benign liver tumour it is diagnoses with ultra sound abdomen for a start then CT scan with contrast is done and then confirmed by biopsy of the tumour. I would suggest you to visit your doctor and get ultrasound done as planned then you can follow it up further with your doctor and ultrasound report will decide what other tests are needed to be done. I hope this answered your question.If you have more queries I am happy to answer.Otherwise rate and close the discussion Regrads. Dr.Saddiq ul Abidin M.B.B.S(Licensed Family Physician) Resident Medicine.