Prospective Screening for Breast Cancer-related Lymphedema

This study is monitoring breast cancer patients before, during, and after treatment to detect lymphedema — a condition where fluid builds up and causes arm swelling — as early as possible, so that it can be treated before it becomes severe. **You may be eligible if...** - You have been diagnosed with breast cancer - You are physically able to hold your shoulder and arm in the required positions for the measurements - You are able to stand without assistance for the measurements **You may NOT be eligible if...** - Your cancer has spread to distant parts of the body in a way that may already be causing swelling - You have had breast cancer before - You already have lymphedema - You are pregnant at the time of enrollment - You have a cardiac (heart) implant such as a pacemaker - You have a medical condition that causes fluid retention or swelling (such as kidney or heart problems) Talk to your doctor to see if this trial is right for you.