Symptoms of kidney cancer include blood in the urine, giving the urine a rusty, pink, or dark red appearance. Persistent pain in the side (flank) is another common symptom, along with an abdominal mass or lump, fever, weight loss, tiredness, and a general feeling of being unwell. However, noncancerous conditions like cysts, benign tumors, or infections are the most common causes of these symptoms. Blood in the urine should always be investigated to determine the cause.

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