Flank Pain
Flank pain or pain in the lower back and side might happen if you are suffering from bladder cancer. This is a result of the spreading of cancer tumors to other parts of your body as well as the obstruction of the urine flow between your kidney and bladder. Depending on your condition, the pain could range from mild to intense or even unbearable. In most cases, you might feel the pain just above your waist, below your rib cage, or both sides of your back. In addition, it often worsens when the bladder gets filled up. [5]
