Bladder cancer begins in the lining of the bladder and often shows symptoms similar to bladder infection, but the two are not directly related. Bladder cancer is caused by abnormal cell growth and blood in the urine is one of the first symptoms. Bladder infections are most commonly caused by bacteria and blood in the urine is a less common symptom. Recurring bladder infections may indicate bladder cancer, but only a doctor can confirm the cause of your bladder infection. If you experience painful urination, blood in the urine, frequent urination, or abdominal pain, consult your physician.