Kidney cancer, also known as renal cancer, is a type of cancer that starts in the cells in the kidney.
The two most common types of kidney cancer are renal cell carcinoma (RCC) and transitional cell carcinoma (TCC, also known as urothelial cell carcinoma) of the renal pelvis. These names reflect the type of cell from which the cancer developed.
The different types of kidney cancer (such as RCC and UCC) develop in different ways, meaning that the diseases have different long term outcomes, and need to be staged and treated in different ways. RCC is responsible for approximately 80% of primary renal cancers, and UCC accounts the majority of the remainder.
Overall five year survival rates in the United States are 73%
In addition to renal cell carcinoma and renal pelvis carcinoma, other, less common types of kidney cancer include:
- Squamous cell carcinoma
- Juxtaglomerular cell tumor (reninoma)
- Bellini duct carcinoma
- Clear-cell sarcoma of the kidney
- Mesoblastic nephroma
- Wilms’ tumor, usually is reported in children under the age of 5.
- Mixed epithelial stromal tumor
Rarely, some other types of cancer and potentially cancerous tumors that more usually originate elsewhere can originate in the kidneys. These include:
- Clear cell adenocarcinoma
- Transitional cell carcinoma
- Renal lymphoma
- Carcinoid tumor of the renal pelvis
Cancer in the kidney may also be secondary, the result of metastasis from a primary cancer elsewhere in the body
Signs and symptoms
The most common signs and symptoms of kidney cancer are a mass in the abdomen and/or blood in the urine (or hematuria). Other symptoms may include tiredness, loss of appetite, weight loss, a high temperature and heavy sweating, and persistent pain in the abdomen. However, many of these symptoms can be caused by other conditions, and there may also be no signs or symptoms in a person with kidney cancer, especially in the early stages of the disease.
Factors that increase the risk of kidney cancer include smoking, which can double the risk of the disease; regular use of NSAIDs such as ibuprofen and naproxen, which may increase the risk by 51% or may not; obesity; faulty genes; a family history of kidney cancer; having kidney disease that needs dialysis; being infected with hepatitis C; and previous treatment for testicular cancer or cervical cancer.
There are also other possible risk factors such as kidney stones and high blood pressure, which are being investigated
Kidney cancer originates in the kidney in two principal locations: the renal tubule and the renal pelvis. Most cancers in the renal tubule are renal cell carcinoma and clear cell adenocarcinoma. Most cancers in the renal pelvis are transitional cell carcinoma.
Treatment for kidney cancer depends on the type and stage of the disease. Surgery is the most common treatment as kidney cancer does not often respond to chemotherapy and radiotherapy. If the cancer has not spread it will usually be removed by surgery. In some cases this involves removing the whole kidney however most tumors are amenable to partial removal to eradicate the tumor and preserve the remaining normal portion of the kidney. Surgery is not always possible – for example the patient may have other medical conditions that prevent it, or the cancer may have spread around the body and doctors may not be able to remove it. There is currently no evidence that body-wide medical therapy after surgery where there is no known residual disease, that is, adjuvant therapy, helps to improve survival in kidney cancer. If the cancer cannot be treated with surgery other techniques such as freezing the tumour or treating it with high temperatures may be used. However these are not yet used as standard treatments for kidney cancer.
Other treatment options include biological therapies such as everolimus, torisel, nexavar, sutent, and axitinib, the use of immunotherapy including interferon and interleukin-2. Immunotherapy is successful in 10 to 15% of people. Sunitinib is the current standard of care in the adjuvant setting along with pazopanib; these treatments are often followed by everolimus, axitinib, and sorafenib. In the second line setting, nivolumab demonstrated a overall survival advantage in advanced clear renal cell carcinoma over everolimus in 2015 and was approved by the FDA. Cabozantinib also looks promising as a second-line treatment.
In Wilms’ tumor, chemotherapy, radiotherapy and surgery are the accepted treatments, depending on the stage of the disease when it is diagnosed.
IMA901 is used to treat people with cancer of the kidneys. It is composed of ten synthetic tumor-associated peptides (TUMAPs), which activate the body’s own killer T-cells against the tumor. Unlike chemotherapy, this process targets the body’s immune responses and mobilizes them to attack the cancer.
The majority of kidney cancers reported in children are Wilms’ tumors. These tumors can begin to grow when a fetus is still developing in the uterus, and may not cause problems until the child is a few years old. Wilms’ tumor is most common in children under the age of 5, but can rarely be diagnosed in older children or in adults. It is still not clear what causes most Wilms’ tumors. The most common symptoms are swelling of the abdomen and blood in the urine.