A kidney mass is a vague description used to refer to any abnormal growth or area that occurs within or on the kidneys. Various types of tumors can occur within the kidneys, including cancerous and benign growths that may or may not present with any warning signs. Diagnostic and screening procedures will likely be done to determine the best course of treatment for a kidney mass.
The kidneys are a pair of bean-shaped organs located below the ribcage on either side of the spine. These organs are responsible for a number of vital tasks, including filtering blood and producing urine. A kidney mass occurs when mutated cells do not follow the normal patterns of cellular growth and death. Instead of dying, these cells accumulate and form a mass of tissue. These masses are often interchangeably known as kidney tumors and renal lesions.
Although the presence of a kidney mass may be a frightening thought, a mass does not necessarily mean that kidney cancer is present. A benign kidney tumor, such as a simple cyst, could be the problem. A simple kidney cyst is a sac of tissue formed in the kidneys that is usually filled with fluid. These simple cysts are fairly common among older adults and generally do not require treatment.
If a solid mass is found in the kidneys, however, a malignant kidney tumor may be present. The most common type of renal cancer in adults is renal cell carcinoma (RCC). RCC is a type of kidney cancer that originates within the filtering tubes of the kidney. Conversely, the most common type of cancerous kidney tumor occurring in children is Wilms’ tumor (WT). It has been suggested that WT is linked to certain congenital defects and may have a genetic cause.
In many cases, benign and cancerous kidney masses will not produce any symptoms. Instead, the masses are often discovered by accident while doing an imaging test for an unrelated reason. Some common symptoms that may present, however, include back pain, fatigue, and a touchable lump in the region of the kidneys. Generally, symptoms are more likely to occur in larger lumps that have been developing for some time.
To determine the most appropriate treatment for a kidney mass, a full evaluation will usually take place. This evaluation will usually include a physical examination along with a discussion of current medical problems to help determine which additional diagnostic and detection tools may be necessary. For instance, having blood in the urine is a symptom generally associated with a kidney mass, and a renal ultrasound may be ordered to help confirm that a mass is present. Other imaging studies, such as a magnetic resonance imaging (MRI) scan, may also be needed to determine if the mass is spreading to other organs.
During the evaluation process, various tests will be used to determine if the kidney mass is cancerous or benign. One test likely to be done is the complete blood count (CBC), a blood test that calculates the concentration of the components of the blood. CBC test results can reveal the number of red blood cells present. Too few and too many red blood cells have both been noted to appear in those with kidney cancer. A biopsy, which involves removing tissue from the mass and examining it under a microscope, may also be needed to confirm the results.
After an accurate analysis of the kidney mass has been made, a doctor will decide on the best course of treatment. If the tumor is benign, no additional treatment may be needed unless the tumor is causing physical symptoms. As for cancerous kidney tumors, treatment will usually include surgery to remove the mass. If the mass is large or spreading beyond the kidneys, the entire organ may have to be removed. Chemotherapy and other drug treatments may also be necessary.