We often assume that we might develop a few odd pains or inconvenient symptoms after age 60 or so. But sometimes, seemingly minor annoyances can signal the onset of a serious disease. That is certainly the case with bladder cancer, which is the fourth most common type of cancer in men (and can affect women as well). If any of these four symptoms happen to you, don’t ignore them, and talk to your doctor about investigating their cause.

Changes in urination. If you need to urinate more frequently, have a weak urine stream, or feel like you need to urinate even when you don’t, it can be easy to confuse these symptoms with a urinary tract infection. Some people simply assume these are normal signs of aging. But in some cases, these can be early warning signs of bladder cancer.

Flank pain. Many people with bladder cancer won’t feel any pain until the disease has quite progressed. But some do notice flank pain, which is pain between the abdomen and lower back on one side. Never just assume this type of pain is related to exercise, a pulled muscle, or some other common ailment.

You see blood in your urine. You might notice a pink or red tinge to your urine, but then it disappears for weeks at a time. Just because a symptom isn’t constant, doesn’t mean it isn’t serious. Even if the blood is not accompanied by pain or any other symptom, you shouldn’t dismiss it.

Your doctor finds traces of blood in your urine. Your doctor might find microscopic amounts of blood in your urine during a routine exam. This tiny amount of blood is often blamed on another cause, such as a urinary tract infection. But in some cases, this early warning sign of bladder cancer is missed (especially in women). Always insist that your doctor rule out bladder cancer if blood is found in your urine.

The good news is that bladder cancer is often found early in its progression, when it can be halted quickly. You can influence the odds in your favor by remaining vigilant regarding the above warning signs and maintaining regular communication with your primary care doctor.