What is kidney cancer?
Kidney cancer is an oncological disease in which a malignant neoplasm occurs, affecting one or both kidneys. Renal cell carcinoma is the most common type of cancer, causing uncontrolled growth of cancer cells and metastases – spreading malignant cells to other parts and organs. Cancer cells provoke the destruction of healthy kidney tissue, due to which they subsequently grow. The body can become fatally poisoned by toxic substances released during tumor growth. Thus, approximately 40% of patients diagnosed with renal cell carcinoma die due to the disease severity. Therefore, this tumor ranks among the deadliest malignant neoplasms.
How is renal carcinoma diagnosed?
Often, kidney cancer is asymptomatic for a long time. The symptoms can be noticed only at a late stage. Several different diagnostic methods help to detect the disease. They are:
- CT with intravenous contrast is the “gold standard” for diagnosing kidney cancer. It can determine the tumor size, location, stage, and effects on nearby organs. Additionally, it detects the metastases in the calyx-pelvic system, abdominal cavity, renal, and inferior vena cava.
- The latest diagnostic technique for kidney cancer is 3D computer modeling of tumor development. They help to carry out organ-preserving and organ-sacrificing surgeries, as well as prepare for nephrectomy.
- Magnetic resonance imaging (MRI) is a less common method for diagnosing a tumor than CT scans and is used when a CT scan is contraindicated.
- Chest X-ray and bone scintigraphy can detect metastases in the lungs and bones.
- Urine & blood test:– With the help of urine analysis, it is possible to detect blood in it. Blood helps identify indirect signs of kidney cancer such as anemia, increased alkaline phosphatase levels, and urea.
- A tumor biopsy is required to confirm the diagnosis and determine further treatment tactics. However, sometimes this method can be uninformative, so it is rarely carried out.
- Renal angiography is performed in case of renal artery embolization procedure.
How is kidney cancer treated?
The treatment regimen of a kidney cancer patient starts only after confirming the condition with multiple diagnoses. The doctor considers the patient’s age, general health, and the prevalence of metastases. Treating renal cell carcinoma can be done through surgery and chemotherapy, immune therapy, radiation, and hormone therapy.
Surgery is considered to be the only way to treat renal cell carcinoma. Laparoscopic and robotic surgical techniques are available. The choice of one of them depends on the tumor size. The idea of using radical nephrectomy for kidney cancer treatment consists of removing the whole kidney and its surrounding tissue without going beyond Gerota’s fascia. Therefore, modern urology oncology offers a wide range of minimally invasive surgical interventions.
Immunotherapeutic drugs are capable of destroying cancer cells:
- Cytokines (interleukin-2, alpha interferon);
- Inhibitors of immunity (nivolumab, pembrolizumab, etc.)
Cytokines are substances similar to natural proteins that activate the immune system. This group of drugs like Interferon-alpha-2a is often used to treat the disease. It stimulates growth and activates T-lymphocytes (immune cells) that help destroy cancer cells. But this drug has serious side effects. Interferon-alpha-2a is considered a more effective cytokine. Immunity inhibitors work quite well with almost no side effects on the patient’s body.
Chemotherapy drugs are usually not the first line of treatment for renal cell carcinoma, but they may be recommended if other treatment options fail. This method is used before and after the operation. In particular, for kidney cancer, the following drugs are used to prevent tumor development: methotrexate, vinblastine, doxorubicin, cisplatin, and a combination of gemcitabine with platinum-based antineoplastic drugs. However, it should be recognized that none of these agents are effective enough in renal cell carcinoma treatment.
This method should be used to reduce the risk of re-emergence of the local form of kidney cancer after surgery. Radiation therapy for renal cell carcinoma is often intended to improve the quality of life. For example, it reduces painful symptoms when bone metastases occur (in about 80% of cases). The radiation doses, in this case, can be as follows:
- Ten times 3 Gy for two weeks
- Five times 4 Gy for one week
Hormone therapy slows down the growth of tumor cells. For this, hormonal drugs such as medroxyprogesterone and tamoxifen are used. Effective treatment of the disease involves the use of several therapeutic methods. However, the most effective is surgery.
What is the prognosis and survival rate of kidney cancer?
The favourableness of kidney cancer depends on how early it was discovered:
- in the case of stage I (T1), the chance of five-year survival is high
- in stage II, the chance of five-year survival is reduced to 50%
- at the III and IV stages, the chance of five-year survival is only 5-20%
According to world statistics, the survival rate of patients with kidney cancer who underwent surgical treatment is:
- at stage I – 81%
- at stage II – 74%
- at stage III – 53%
- at stage IV – 8%
Unfortunately, effective preventive methods for kidney cancer have not been developed. However, smoking cessation, weight control, and proper nutrition can prevent kidney cancer.
What are the most common symptoms of kidney cancer?
Malignant neoplasms in the kidney do not show any signs and symptoms until the late stage of cancer. An ultrasound is usually the typical way most malignant tumors are diagnosed.
Arterial hypertension is noted in 15% of patients with kidney cancer. Hematuria, palpable swelling, and lower back pain – have recently become fewer common signs (6-10%). Paraneoplastic syndromes occur in approximately 25% of patients diagnosed with renal cell carcinoma.
- Blood in the urine.
- A lump in the loin area or abdomen.
- A loss of appetite.
- A pain in the loin area that does not fade away.
- Weight loss without a known cause.
- Fever that lasts several weeks and is not caused by a cold or any other infection.
- Extreme fatigue.
When DNA in cells of one or both kidneys is mutated, it can cause kidney cancer. This may result in uncontrolled cell division and growth.
The carcinogens contained in tobacco cause renal cell carcinoma. Smokers account for 70% of kidney cancer patients. Other contributing factors include obesity and high blood pressure. Uncontrolled growth of cancer cells causes tumor formation.
The tumor grows and becomes larger, eventually reaching the kidney via the bloodstream and lymph. It enters into other organs, lungs, bones, and the brain.
Although the cause of kidney cancer is not known, there are certain risk factors that can be linked to it, such as smoking and obesity.
It has been possible to identify the risk factors that influence the development of cancer. These include:
i. Active and passive smoking increase the risk of developing the disease by 50%
ii. Long-term use of diuretics – by 30%
iii. Increased body weight (metabolic syndrome) – by 20%
iv. High blood pressure – by 20%
v. Professional exposure (work with chemicals and dyes)
vii. Long-term hemodialysis therapy
viii. Viral hepatitis
ix. Genetic predisposition
x. Polycystic kidney disease
xi. Von Hippel-Lindau disease
Picture Courtesy: ncsmpg
Metastases are the most dangerous complications of renal cell carcinoma. Unfortunately, they occur in almost every fourth patient. Despite the radical operation to remove the affected organ, kidney cancer metastases reappear in 30% of cases.
There are three factors closely related to kidney cancer. Kidney cancer in men occurs 1.5-2 times more often than in women. A person who smokes. Smoking, as part of cigarette carcinogenic substances, passes through the kidney. Obesity and arterial hypertension are often associated with kidney cancer.
It depends mainly on the stage at which the tumor was diagnosed and when treatment starts. The five-year survival rate is highest during stage I and is 81%. In stages II and III, it is 74 and 53%, respectively. At stage IV – 8%.
The stage of kidney cancer depends on the size and location of the tumor. So, kidney cancer of the first stage is a tumor less than 7 cm that does not go beyond the kidney. Stage II is a less than 10 cm tumor and does not extend beyond the kidney. But stage III is a tumor of any size. Stage IV may be any size. However, at this stage, the tumor can either grow beyond the renal fascia or have more than one metastasis to nearby areas.
The types of kidney cancer are:
a. Renal cell carcinoma
b. Clear cell renal cell carcinoma
c. Non-clear cell renal cell carcinoma
d. Other types include- Transitional cell carcinoma, renal sarcoma, Wilms tumor (nephroblastoma)
Kidney cancer affects about 3.7% of all cancers in the USA. Every year approximately 62000 Americans are diagnosed with kidney cancer. The risk increases with age.