What causes painless lump on the right side of rib cage?

Inside your body, you have many kinds of tissue, including fat, muscle, bone, and organs. A lipoma is a soft, non-cancerous lump made of fat that can form under the skin and is usually not painful. Lipomas are relatively common. Enlarged lymph nodes are also common and can also form a lump; these are part of your body's defense system and sometimes swell without hurting if there is no active infection. Lumps could also be related to growths from bone, muscle, blood vessels. They can also be related to cysts (a closed pocket of fluid). Many times, these lumps do not cause pain and may be discovered by accident. Although painless lumps are often benign (non-dangerous), it is important to get them checked by a healthcare provider especially if they are increasing in size or become painful. If you've discovered a lump and want to better understand what it might be, try our free AI symptom checker to help guide your next steps. Your provider can do a physical examination and imaging studies to find out what is causing the lump and decide if any treatment or follow-up is necessary.