Renal cell cancer (also termed renal cell carcinoma or RCC) is a disease that occurs when certain kidney cells become malignant or cancerous and grow out of control, forming a tumor in one or both kidneys; there may be more than one tumor formed. The renal cancer cells may metastasize (spread) to other areas of the body.
Renal cell carcinoma risk factors
Risk factors for developing RCC include
- male gender,
- long-term dialysis,
- exposure to certain chemicals,
- high blood pressure,
- black race, or
- having lymphoma.
Also, having a family history of RCC or having certain genetic conditions will increase a person's risk. The causes of kidney cancer are not clear; however, it's likely that kidney cancer begins when kidney cells mutate or a person inherits certain genes. Readers should note that some authors use RCC and the term "kidney cancer" interchangeably. For this article, RCC does not stand for all types of "kidney cancers" but represents one type.
Renal cell carcinoma symptoms and signs
Although RCC frequently causes no symptoms in its early development, eventually signs and symptoms may develop and include
- weight loss,
- constant back pain,
- a mass or lump on the lower back or side,
- blood in the urine (hematuria),
- anemia (low red blood cell counts), and
- intermittent fevers.
Over 62,000 individuals are predicted to be diagnosed with kidney cancers in the U.S. in 2016; about 90% are predicted to be renal cell cancers. About 14,000 individuals are predicted to die from all types of kidney cancer disease in 2016. Men are about twice as likely as women to get RCC; also, RCC is uncommon in people younger than age 45, with the average age at diagnosis being about 64 years old.
Types of renal cell carcinoma
The subtypes of RCC are mainly based on their microscopic appearance. The most common type is clear cell (70%), with cells that appear pale or clear. Papillary renal cell cancers (10%) form little finger-like projections termed papillae; these are also termed chromophilic because these RCC types uptake certain dyes and can appear pink. The third type is chromophobe (5%); these cells resemble the appearance of clear cells that are considerably larger.
There are rare types of RCC; they are as follows:
- Collecting duct RCC
- Multilocular cystic RCC
- Medullary carcinoma
- Mucinous tubular and spindle cell carcinoma
- Neuroblastoma-associated RCC
- Unclassified RCC
Diagnosis and staging of renal cell carcinoma
The diagnosis of RCC begins with a person's history and physical examination. In addition, blood and urine tests may be done. Other imaging tests such as ultrasound, CT, or MRI may be ordered. Tests such as a bone scan, angiography, intravenous pyelogram (IVP), and/or a PET scan may also be considered. A sample of tissue (biopsy) may be removed from the affected area of the kidney to accurately determine the type of kidney cancer and/or the stage or extent of spread of the cancer. Your primary-care doctor may consult other doctors. The specialists who recommend and/or perform some of these tests are oncologists, urologists, and occasionally, urologic surgeons and radiologists. Cancer staging for kidney cancers usually range from stage I to stage IV, with stage IV as being the most severe cancer. Staging is as follows:
- Stage I tumors are confined to the kidney and less than 7 cm in diameter.
- Stage II tumors are confined to the kidney and greater than 7 cm diameter.
- Stage III tumors have spread from the kidney to the surrounding tissue or nearby lymph nodes.
- Stage IV tumors have spread outside the kidney to multiple lymph nodes and/or other organs such as the bones or lungs.
Another staging system may be used by some doctors either in conjunction with the above staging system or separately. It's termed the TNM system (T indicates the size of the tumor and if it has spread to other areas; N describes the extent of spread the tumor to lymph nodes; and M indicates metastasis to other organ systems.) and is more detailed than the stage I-IV system but essentially similar to it.
Treatment of renal cell carcinomaThe treatment of kidney cancer is often decided by the patient and physician and is based on the tumor stage and tumor type. Consequently, the treatment of a particular stage and type of kidney cancer may involve one or more the following:
- Surveillance (repeated assessment without intervention)
- Ablation (destruction of tumor cells by cryotherapy, radiofrequency, or embolization)
- Radiation therapy
- Targeted therapy (drugs specially developed for a particular cancer type)
Renal cell carcinoma life expectancy (survival rate)
The American Cancer Society suggests that the prognosis is good for patients diagnosed with stage I or stage II RCC (81% and 74% respective five-year survival rates). The prognosis worsens as stage III and IV develop. RCC treated early can result in a relatively normal life span; however, the lifespan decreases in later stages.
Renal cell carcinoma prevention
Prevention or reduction in the chance of developing RCC is linked to preventable risk factors. Those types of risk factors include the following:
- Cigarette smoking
- High blood pressure
- Organic solvent exposure
- Cadmium exposure (workplace exposure in types of battery construction, for example)
Avoiding those risk factors can reduce the chance of the person developing kidney cancer. However, RCC that are due to inherited genetic changes are currently not preventable.
The Kidney Cancer Association offers a helpline at a toll-free number: 1-800-850-9132.
Since early treatments yield the best outcomes, if you suspect you or a loved one to have kidney or renal problems, do not hesitate to contact your primary-care physician immediately.