Renal cell carcinoma, also called hypernephroma, is a cancer of the kidneys that forms in the proximal convoluted tubule. In the UK, it is the eighth most common cancer among adults, affecting 9,300 people every year.
The kidneys are bean-shaped organs found on either side of the body, just below the ribcage. The kidney is made up of functional units called nephrons that regulate the water and sodium concentration as well as eliminating waste products from the blood via the urine. Some of the main structures that make up a nephron include the glomerulus, the proximal convoluted tubule, the cortical collecting duct, the distal convoluted tubule, the loop of Henle and the juxtaglomerular apparatus.
Renal cell carcinoma originates in the lining of the proximal convoluted tubule, which is involved in carrying waste from the blood to the urine. Renal cell carcinboma is one of the most common forms of kidney cancer, accounting for around 90% of cases. Renal cell carcinoma is often a fatal condition because it tends to go unnoticed until the cancer has reached the advanced stages of disease.
Diagnosis is mainly based on imaging studies of the abdomen including ultrasound examination, a computed tomography (CT) scan and a magnetic resonance imaging (MRI) scan. These images are used to look for any changes in the shape of the kidney that may indicate the presence of cancer. Diagnosis is confirmed by biopsy and examination of the tumor tissue under the microscope.
On deciding how a patient should be treated, a physician will take into consideration the stage and grade of the cancer, as well as the patient’s age and general health status. If the cancer is confined to the kidney, it can usually be treated through surgical removal of part or all of the kidney. Cancer that has spread beyond the kidney may be impossible to cure and instead treatment may be focused on slowing progression of the disease and alleviating symptoms.
If diagnosed in the early stages, the prognosis for renal cell carcinoma is usually positive. Sixty-five to ninety percent of individuals diagnosed in the early stages of disease will survive for at least five years after their diagnosis. For cancer that has spread beyond the kidney, this five-year survival rate is reduced somewhat, to 40–70%. In cases of advanced cancer that involves other parts of the body, only 10% of patients live for at least five years after their diagnosis.