One of the main functions of the kidneys is to filter the blood and get rid of unnecessary waste from the body. When cancer develops in this organ, it shows very few symptoms in the initial stages. In several cases, the condition got diagnosed in the earlier stages because the concerned person was getting an X-ray or an ultrasound done for a completely different reason. The most common form of kidney cancer observed in people is renal cell carcinoma.

The initial symptoms of kidney cancer are often observed in the urine or manifest as discomfort in the lower back area. It would be prudent to note the following early warning signs and symptoms of kidney cancer.

• Blood in the urine
  This symptom is observed in about 40-60 percent of people who are suffering from kidney cancer. The condition in which blood is observed in urine is also known as hematuria. The amount of blood observed in the urine may vary from person to person and as a result, the excreta may appear pink, brownish, or even red.
• Lower back pain
  Lower back pain is a very common condition and is not always associated with kidney cancer. It is usually observed among a majority of people in old age, or those with sedentary lifestyles. In people suffering from renal cell carcinoma, the symptom of lower back pain is observed in the initial stages of cancer. The intensity of the pain may vary from individual to individual and hence, any persistent pains lasting more than a few days must be reported to a professional to avoid any unwanted surprises.
• Lump or mass in the abdomen
  If a person starts to feel a sudden lump or mass in their lower abdomen or back area, it could be a sign of kidney cancer. While such lumps associated with kidney cancer are difficult to spot in the early stages, if you do discover or feel one, the doctor may advise you to undergo diagnostic tests like an ultrasound or a CT scan. This can usually detect the presence of any benign or malign tumor.
• Anemia
  The kidneys are responsible for making a hormone known as erythropoietin, which assists the bone marrow in the production of red blood cells. When kidneys are not functional, this activity is inhibited which may lead to a lowering of the RBC count in the human body. Anemia could also cause symptoms like shortness of breath, dizziness, pale looking skin, and terrible fatigue.
• Unexpected weight loss and fatigue
  In any form of cancer, the most common symptom observed is fatigue, which is much more prominent than just feeling a little tired and can largely affect a person’s quality of life. Moreover, when the tumor or the cancerous cells metastasize to other parts of the body, a person can observe rapid weight loss. The patient loses his or her appetite and can also show signs of unexpected fevers.