Kidney metastasis

The term "metastasis" has Greek roots - meta stateo, which means "located differently". This accurately characterizes secondary formations of a malignant oncological process, since almost 90% of cancerous tumors are accompanied by foci localized not only in regional lymph nodes, but also in organs distant from tumors, most often in the lungs, liver, spine, and brain. Metastases in the kidneys are less common, mainly in oncological processes that can produce widespread secondary foci. Such tumors include melanomas, lymphomas, and bronchogenic cancer (bronchogenic carcinoma). Metastasis to the kidney also occurs in cancer of the pharynx, larynx, adrenal tumors, liver, stomach, and breast cancer. In 10-12% of cases, a secondary pathological focus in the kidney is formed in cancer of the contralateral (opposite) kidney. The oncologic process affects the renal parenchyma and pelvis in various ways - directly through the introduction of atypical cells from a nearby adjacent organ, but most often through hematogenous, lymphogenous, venous or aortic routes. Renal cell, urothelial cancer, nephroblastoma (Wilms' tumor) as independent processes are also capable of metastasizing to the lungs, spine, bones, brain and liver. In oncological practice, RCC (renal cell cancer) is classified according to the generally accepted TNM system, where the letter M (metastasis, Mts) denotes the absence or presence of distant metastases.

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Kidney cancer and lung metastases

The lungs "lead" in the frequency of metastasis in any oncopathology, this is due to the blood supply system, the capillary network of the organ, and also to the fact that it is the lungs that are the first to pass through themselves almost all the venous blood flow, filled with large lymphatic vessels located in different areas of the body.

In kidney cancer, metastases develop according to the cascade principle. In this process, the lungs act as the primary barrier that malignant atypical cells encounter.

Kidney cancer and metastases to the lungs are the most typical phenomena in this pathology; according to statistics, metastasis to the bronchopulmonary system accounts for about 60-70% of the total number of secondary tumors in RCC. Such a threatening "preference" is due to the fact that the lungs are a kind of filter for the kidneys, the venous blood of which enters the bloodstream of the superior and inferior vena cava, unlike the organs of the gastrointestinal tract, which are protected by the liver.

Metastases to the lungs are considered distant secondary foci; patients with such manifestations are divided into 2 categories:

1. Kidney cancer and metastases to the lungs are diagnosed at the first visit to the doctor (which happens extremely rarely).
2. Metastasis to the bronchopulmonary system occurs in a delayed manner, several years after removal of the primary tumor in the kidney.

The most effective methods of treating single metastases in the lungs are surgical treatments and long-term combination therapy. Currently, secondary foci in this organ are successfully treated using TT – targeted therapy. This is a modern technology for treating metastases, which uses antitumor drugs (monoclonal antibodies) of targeted action. Unlike cytostatic therapy, TT specifically neutralizes aggressively multiplying cancer cells in the lungs. Thus, patients with RCC metastasizing to the lungs receive not only hope for prolonging their lives, but also a real chance of gradual recovery. Considering that single secondary foci in the lungs tend to regress, these chances increase.

Kidney cancer and bone metastases

Bone metastases in kidney cancer occupy the second place in the list of secondary foci development. Kidney cancer and bone metastases are diagnosed in 30-35% of patients, the most typical localization is the pelvic bones, much less often atypical cells penetrate the bone tissue of the ribs, hips, spine, only 3% are metastases in the bones of the cranial vault.

How do bone metastases manifest in kidney cancer?

• Pain when moving (walking), pain that does not subside at rest as the process progresses.
• Deformation of the pelvic bones, gait disturbance, hip asymmetry.
• Muscle weakness.
• Pathological fragility of bone tissue, fractures (oncoosteoporosis).
• Hypercalcemia.

When metastasizing to bone tissue, two types of pathology develop:

• Osteolytic foci – leaching, demineralization of bone.
• Osteoblastic secondary foci – compaction of bone tissue, hypercalcemia.

Unfortunately, bone metastases in kidney cancer are detected at late stages of the process, the primary development is most often asymptomatic. The main diagnostic methods confirming metastasis to bone tissue are plain radiography and scintigraphy. Osteolytic metastases are better visible on X-rays, as they are accompanied by pronounced hypercalcemia. Osteoplastic foci are more accurately determined by scintigraphy, and X-rays can be an addition, revealing bone compactions and osteosclerotic zones.

Most often, bone metastases are provoked by disseminated tumors, in which secondary foci spread very quickly. Treatment of such a process is extremely difficult, unlike solitary metastases, which are subject to radical removal and radiation therapy. Multiple foci are subject only to palliative therapy, which can reduce the severity of symptoms and at least slightly improve the patient's quality of life. Radiation therapy can also play the role of a kind of analgesic, although it requires a system of repeated sessions, which are often contraindicated for patients with RCC.

Kidney cancer and metastases to the spine

Metastasis in the spine develops as a result of penetration of atypical cells into the spine by hematogenous route. Bone lesions begin in the epidural venous plexus zone, that is, in the zone through which malignant cells are introduced. Kidney cancer and metastases in the spine are evidence of stage III or IV of the disease, the symptoms of which have already manifested themselves in full force and provide detailed information for more accurate diagnosis.

The main symptom of spinal metastases is considered to be severe pain, it is observed in 90% of patients. Intense pain is localized in the area affected by cancer, it is often similar to typical radicular pain, but exceeds it in strength and frequency. In addition, in advanced stages of RCC, visible compression of the spine with characteristic pelvic disorders, with tetraplegia (paralysis of all limbs) or paraplegia (in this case, paralysis of the lower limbs) is diagnosed in 5% of patients. Tetraparesis is accompanied by systematic muscle spasticity, mainly in the lower limbs (legs), then the muscles of the arms can join the process. Paraplegia manifests itself with the same symptoms, but develops faster, most often with a pathological fracture of the vertebrae, characteristic of generalized metastasis. The most typical localization of metastases in the spine in kidney cancer is the lumbosacral region, when there is osteoplastic damage to the zones L2, L3, L4, L5, S1. The zonal frequency of metastases in the spine is distributed as follows:

• Lumbar region – 45%.
• Thoracic spine – 25%.
• Sacrum – 30%.

Metastases in the cervical region and cranial vault in kidney cancer are extremely rare; these isolated cases cannot serve as a basis for statistical processing; rather, they are evidence of an extremely advanced generalized oncological process.

Just as with metastases in bone tissue, secondary foci in the spine are divided into osteolytic and osteoblastic. Their symptoms are united in one sign - pain, but hypercalcemia can also manifest itself with symptoms that are very important in terms of early detection of kidney cancer:

• Constant muscle weakness.
• Neurotic disorders, depression.
• Weight loss, loss of appetite.
• Nausea, rarely vomiting.
• Persistent hypotension.
• Change in normal heart rhythm.
• Compression pain.
• Pathological fractures of the vertebrae.

The clinical picture of metastasis to the spinal column is characterized by profound neurological disorders. Loss of sensitivity of the extremities and control of movements occurs several months after the appearance of the first lesion, when the spinal cord is subjected to pressure and compression occurs, followed by a fracture of the vertebra. Such late compression symptoms are due to the localization of secondary tumors that form in the bone substance, and not in the canal. The lesions spread into the bone tissue, endophytically, after which cracks, fractures and compression of the roots develop.

Kidney cancer and metastases in the spine are determined by the following methods:

• Collection of anamnesis.
• Inspection.
• Physical examinations.
• Analysis of the level of ALP – alkaline phosphatase.
• Analysis to determine the level of calcium in bone tissue.
• X-ray of the spine.
• Radioisotope examination – scintigraphy.
• Computed tomography (the gold diagnostic standard for detecting bone metastases).
• NMRI - nuclear magnetic resonance imaging.

Most often, metastases in the spine are treated with palliative methods; many oncologists consider surgical intervention to be unpromising in terms of effectiveness. The only alternative may be radiosurgery and the CyberKnife apparatus, but not every oncology center has such equipment. Therefore, as a rule, metastasis in the spinal column is subject to traditional methods of treatment - radiation therapy, administration of corticosteroids, bisphosphonates, immunotherapy, chemoembolization. Pain symptom in case of vertebral fracture is often anesthetized with Spinal Cord Stimulation - SCS or epidural stimulation with electrodes. This method allows you to manage pain syndrome in the pelvic area of the spine and control the degree of rigidity of the muscular system, spasticity.

Spinal metastases are considered an unfavorable prognostic criterion.

The data that statistics show for the last 15 years are as follows:

• Some patients diagnosed with kidney cancer and spinal metastases can move independently. Limited mobility and motor activity are generally preserved in 90% of cases after combined long-term therapy, in 75% of cases after nephrectomy. Life expectancy is from 1 year to 1.5 years.
• If the primary tumor is amenable to radiotherapy, the development of spinal metastases can be stopped in 30% of patients, significantly increasing the chances of prolonging survival.
• After radiation therapy, 50% of patients with mild paralysis of the legs (paraparesis) retain the ability to move.
• 10-15% of patients with paraplegia will be able to move after radiation therapy sessions aimed at stopping metastases in the spine.
• Completely immobilized patients have poor prognosis in terms of survival, only 10% of them live just over 1 year.
• In 99% of cases, pelvic dysfunction becomes irreversible 3-6 months after the appearance of the first metastasis in the spine.

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Kidney cancer and brain metastases

Metastasis to the brain is diagnosed 1.5 times more often than primary oncopathology of the brain. Secondary foci in the brain can give almost all malignant formations, but most often this is noted in lung and breast cancer. Kidney cancer and metastases to the brain are diagnosed in 15-20% of all oncological diseases, according to information from other sources, their frequency reaches 35%.

The clinical picture of brain metastases can be different, since before the central nervous system is affected, secondary foci first capture the bronchopulmonary system, regional lymph nodes, liver, adrenal glands, bones and contralateral kidney. The process of metastasis spread is inevitably accompanied by specific symptoms, against which the signs of Mts (metastases) of the brain are initially lost. Slow but constant progression can be interrupted by sudden attacks of headache - episodes of spontaneous increase in electrical activity. It is almost impossible to differentiate metastases from a primary brain tumor by clinical signs, since all of them are characteristic of both independent oncopathology and secondary focal brain damage.

Symptoms that may indicate kidney cancer and brain metastases:

• ICP is increased, blood pressure may increase in “jumps” that are not amenable to treatment with antihypertensive drugs.
• Attacks of headache.
• Paresthesia.
• Epileptoid seizures, convulsions.
• Increasing cerebellar ataxia (impaired coordination of movements).
• Periodic febrile conditions.
• Mental instability, hyperlability.
• Impaired cognitive function.
• Disorders of mnemonic functions (memory).
• Noticeable changes in personality traits.
• Asymmetry or different pupil sizes.
• Speech disorders.
• Visual dysfunctions.
• Nausea, vomiting.
• General weakness.

The gold standard in the diagnosis of brain metastases is neuroimaging, that is, CT - computed tomography, which can be performed in various modifications - MRI, MRI with contrast, NMRI. Treatment of secondary foci in the brain is carried out mainly by palliative methods, since such complicated tumors have an unfavorable prognosis. Even with complex intensive therapy, the life expectancy of patients with diagnosed Mts - brain metastases does not exceed 7-8 months. Generalized therapy algorithm when kidney cancer and brain metastases are confirmed by neuroimaging methods:

Clinic	Choice of therapy method
Focal lesion of unknown etiology	Stereotactic biopsy for histological examination and tumor drainage
Disseminated brain metastasis, Karnofsky performance status < 70, apparent negative functional status	Radiation therapy of all cerebral arteries, WBI – whole brain irradiation Refusal of any treatment method due to its inappropriateness
Solitary metastases	Surgical methods – removal, with mandatory radiation therapy RT – radiation therapy and intensive stereotactic radiosurgery (SRS)
Widespread, multiple metastases with one, largest, “leading” one	Surgical removal, radiotherapy (OBM)
Multiple lesions that cannot be removed	WBI – whole brain irradiation OVM and SRH

It should be noted that brain metastases of any development and extent are treated with radiation therapy. In the case of single solitary lesions, RT helps to stop the process; non-removable, multiple metastases are subject to irradiation to reduce pain symptoms. Target therapy for secondary lesions of such localization is not used due to its complete ineffectiveness.

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Kidney cancer and liver metastases

Malignant tumors are capable of spreading their atypical cells to regional zones, as well as to distant organs. Most often, this occurs in the most accessible way - hematogenous, metastasis through the lymphatic vessels is possible, less common is the germination of malignant cells directly from the affected organ to the neighboring one. Kidney cancer and metastases to the liver are diagnosed extremely rarely, according to various sources, this occurs in 2-7% of patients. The liver is affected due to the peculiarities of its circulatory system. It is known that the main role of the liver in the body is detoxification, which requires increased blood flow activity. Blood enters the organ through the main arteries, with the help of the portal system (portal vein). In 1 minute, the liver is able to process up to 1.5 liters of incoming blood, about two-thirds of the blood flow enters the liver from the intestine. Such active work with blood creates a favorable background for the penetration of malignant structures into the liver. It should be noted that hematogenous foci in the liver are formed regardless of the connection of the primary tumor with the portal system. Obviously, this is due to the main detoxifying function of the organ, which absorbs everything that is in the bloodstream.

The clinical picture of liver metastases is characterized by an asymptomatic course of the process in the initial stages. Atypical cells slowly but systematically replace liver tissue, causing its dysfunction. During random biochemical examinations, an increased level of fermentation (AST, ALT) is noted in the analyses; at the stage of active development of foci, most often in III and IV, symptoms of massive intoxication and jaundice may be noted. The clinical manifestations of developed metastases are as follows:

• Constant feeling of fatigue.
• Steady weight loss.
• A feeling of heaviness in the right hypochondrium, in the upper abdominal area.
• Attacks of dull pain in the abdomen, similar to signs of bile duct obstruction.
• Increased sweating.
• Subfebrile temperature.
• Itchy skin.
• Periodic attacks of tachycardia.
• An enlarged abdomen – ascites – indicates the involvement of the peritoneum in metastasis, as well as thrombosis of the portal system.
• If metastases form as dense nodes, peculiar depressions on the surface of the abdomen (umbilical indentations) are possible.
• Due to the fact that blood flow is greatly slowed down due to the development of secondary foci, there are no arterial noises during percussion.
• Splenomegaly indicates that the pathological process is advanced.
• Yellowing of the skin and whites of the eyes may be a sign of atypical cell invasion into the bile ducts. This symptom is extremely rare.

In diagnostics of secondary focal liver lesions, neuroimaging methods – CT, MRI – still occupy the leading position. Ultrasound scanning is uninformative in this case, and computed tomography can show the condition of liver tissue, multidimensional tumor indicators and its metastases.

Kidney cancer and liver metastases are considered a severe oncological disease with an unfavorable prognosis. Systemic therapeutic measures can give results only in the first two stages of the process, a combination of chemotherapy and hormonal therapy somewhat slows down the development of secondary foci. Surgical treatment is indicated only for single metastases, this makes it possible to improve the patient's quality of life and prolong his life. The feasibility of the operation is determined by the oncologist depending on the size, localization of the primary tumor and its secondary formations. Surgical methods are often contraindicated, as they carry anesthetic risks, especially in stages III and IV of kidney cancer. An advanced oncological process can only be cured by nephrectomy, provided that the patient is in a relatively normal condition. The use of cytostatics is effective only in the initial stage of tumor formation and metastases, intensive chemotherapy in combination with RT (radiation therapy) is aimed at reducing the size of foci and preventing the appearance of new ones in nearby areas. Systemic therapy, which includes cytostatics, targeted therapy drugs and embolization of vessels that feed the diagnosed metastases, gives a good effect. Chemotherapy is not used in the treatment of multiple liver metastases, and interferon therapy or a combination of interferons and interleukins following surgery helps to reduce pain symptoms and increase the patient's life expectancy.

Symptoms of kidney metastases

The specificity of metastasis in RCC (renal cell carcinoma) is that clinical manifestations most often indicate stage III or IV of the process. The initial development of secondary foci, wherever they are localized, is characterized by asymptomaticity, which significantly complicates treatment and aggravates the prognosis of the disease. More than a quarter of patients who are diagnosed with kidney cancer for the first time already have metastases in regional lymph nodes or distant organs.

In general, the symptoms of kidney metastases are specific to the affected area (organ) and can be as follows:

• Lung metastases:
  • Constant shortness of breath.
  • Frequent cough, worse at night.
  • A feeling of heaviness and tightness in the chest.
  • The presence of blood in mucus when coughing, hemoptysis.
• Kidney cancer and bone metastases:
  • Localized pain in the bone, in the spine area.
  • Gradual increase in lethargy and fatigue.
  • Steady restriction of physical activity.
  • Pathological fractures.
  • Numbness of the lower limbs.
  • Compression pain.
  • Lower paraplegia (paralysis of the legs).
  • Complete immobilization.
  • Bladder dysfunctions are possible.
  • Hypercalcemia – nausea, weight loss, hypotension, depression, dehydration.
• Brain metastases:
  • Ataxia.
  • Dizziness.
  • Headache (migraine-type attacks).
  • Decrease in cognitive functions – memory, speech, thinking.
  • Depression.
  • Changes in personality traits, mental disorders.
  • Facial asymmetry.
  • Different sizes of eyes and pupils.
  • Nausea, vomiting.
  • Fatigue, constant drowsiness.

General symptoms of metastasis are characterized by a decrease in hemoglobin levels (anemia), an increase in ESR, subfebrile temperature, an increase or decrease in blood pressure, a decrease in body weight (blastomatous process), severe pain both at the site of metastasis and in areas distant from them.

Metastasis of kidney cancer

Metastases of the oncological process in the kidney account for more than half of the clinical signs of cancer and are diagnosed in 45-60% of patients. Unfortunately, the presence of metastases indicates an advanced stage of cancer, when secondary foci are considered a more severe pathology than the primary tumor. Metastasis affects many organs, the localization of secondary foci by frequency is statistically determined as follows:

• lungs,
• lymph nodes,
• pelvic bones,
• spine,
• costoclavicular space,
• bones of the cranial vault,
• liver,
• adrenal glands,
• contralateral kidney,
• brain.

Lung metastases account for about 45% of all secondary foci in kidney cancer, due to the anatomical location of the organs and their venous connections. The renal venous system and the main vessels of the chest interact closely, so the spread of atypical malignant cells is almost inevitable, primarily in the bronchopulmonary system.

The most closely located metastases of cancer in the kidneys are localized in the lymph nodes - paraaortic, located along the aorta, and in the retroperitoneal, paracaval nodes. The lymph nodes of the neck, mediastinum, inguinal nodes are affected much less often, local metastases can be found in the perinephric layer of tissue or in postoperative scars, such cases are diagnosed in 25% of patients who have undergone nephrectomy.

Metastasis as a process occurs primarily through the hematogenous route – to distant organs; the lymphogenous route is considered the most unfavorable when regional lymph nodes are extensively affected.

It should be noted that the peculiarity of metastasis in RCC is the delayed manifestation of clinical signs of secondary foci. Sometimes metastases can be detected 10 years after the removal of the primary formation in stage I. In this case, secondary foci develop less aggressively and are treated more successfully. In addition, there is another characteristic feature: single metastases in the lungs can regress on their own, especially after timely nephrectomy in the initial stage of the oncological process. In this regard, accurate diagnosis of kidney cancer plays an important role, since its early detection can significantly increase the patient's life expectancy.

Diagnosis of kidney metastases

There is no standardized, universal scheme for determining secondary metastatic tumors in RCC, since kidney cancer is divided into types, stages according to the international classification, and each of its variants requires an individual approach to the choice of diagnostic methods. Diagnosis of kidney metastases is difficult in principle due to late manifestations of clinical symptoms, when it is sometimes impossible to separate the sign of the primary tumor from the manifestations of secondary foci. Regional metastases localized in the lymph nodes are most easily determined. Remote organs that are affected by atypical cells hematogenously do not always clearly demonstrate metastatic foci, especially at the initial stage of the process. Nevertheless, we consider it possible to cite as an example the following methods of diagnostic actions in the search for distant foci in RCC:

X-ray, radiography	Blood serum tests	Ultrasound examination	Neuroimaging
X-ray of the lungs	Determination of the level of alkaline phosphatase, ALT, AST	Ultrasound of the kidneys	CT – computed tomography (brain, skeletal system, liver)
Chest X-ray, mediastinum	Liver function tests	Ultrasound of abdominal organs	MRI - magnetic resonance imaging (brain, liver, skeleton)
X-ray of the abdominal cavity	Determination of calcium and LDH (lactate dehydrogenase) levels	Ultrasound of the heart (as indicated in advanced stages of the process)
Radioisotope renography (kidney x-ray)	Tumor markers	Ultrasound of regional lymph nodes

Also informative are scintigraphy, which shows the slightest structural changes in the skeletal system, and angiography, which determines the state of the vascular system that feeds secondary foci.

Diagnosis of kidney metastases is most often carried out according to the "gold" standard in practical oncology - using computed tomography, which allows you to clearly see the condition of the abdominal organs, pelvic organs, chest, lungs, skeletal system and brain. Many image options allow the attending physician to create an objective clinical picture of the disease and choose the right therapeutic direction, decide on the volume and effectiveness of surgical intervention. CT is performed by contrast and conventional methods, contrast gives more informative images, the appropriateness of contrast CT is determined by an oncologist-diagnostician. MRI is more often used when metastases in the brain are suspected, just like CT, this method gives an objective visual "description" of the patient's neurological status.

In diagnostics of secondary foci, cytological methods of urine examination, biopsy (including fine-needle biopsy), urethroscopy, coagulogram can be used. One of the latest analytical achievements in practical oncology is considered to be the method of immunodiffusion research, which determines deep dysfunctions of metabolism, changes in the level of serum proteins, albumin, ferritin, transferrin. The immunological method of diagnostics is carried out in different ways:

• Radial immunodiffusion reaction.
• Immunoelectrophoresis.
• Double immunodiffusion.
• Counter immunophoresis.

Currently, immunological analysis is one of the most effective in the early diagnosis of both primary kidney tumors and their secondary foci, which allows cancer to be detected at the very beginning of development and significantly improves the prognosis in terms of life expectancy and the period of remission after complex treatment.

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Treatment of kidney metastases

Therapeutic measures for kidney cancer with metastases always present a huge problem, since such a stage of the process is poorly controlled by chemotherapy, and radiation therapy is considered ineffective in principle. RCC (renal cell carcinoma) is very resistant to cytostatics due to the aggressiveness of the glycoprotein of tumor cells (P-170), which quickly removes cytotoxic substances and their metabolites, preventing their effect. According to long-term clinical studies, the effectiveness of chemotherapy for metastatic kidney cancer is only 4-5%. However, cytostatic therapy is still prescribed as a possible method, especially since the latest pharmacological developments give hope for increased effectiveness of new drugs when affecting atypical cells. Currently, treatment of kidney metastases can be carried out using new-generation pyrimidines. The drug Xeloda (Capecitabine) helps reduce the severity of symptoms and achieve a one-year remission in 9% of patients. Also approved for use are Nexavar, Torisel, Sutent, Sunitinib, Sorafenib - targeted therapy.

In the treatment of secondary foci in kidney cancer, immunotherapy plays an important role, which is divided into the following types:

1. Non-specific interleukin or interferon therapy, as well as therapy using other MBRs – biological response modifiers.
2. Therapy using ALT - autolymphocytes, LAK - lymphokine-activated killers, TIL - tumor-filtering lymphocytes. Adaptive cellular immunotherapy.
3. Immunotherapy using monoclonal antibodies. Specific therapy.
4. Gene immunotherapy.

Treatment of kidney metastases involves the administration of interferon group drugs, interleukins:

• Reaferon.
• Nitron-A.
• Roferon.
• Velferon.
• Proleikin.
• Interleukin-2.

The combination of cytostatics and cytokines allows achieving tumor regression in 30% of patients, provided that metastases are characterized as single, small and localized in the lungs. In case of metastasis to the bone system and brain, treatment with interferons is not effective, since this stage is, in principle, unfavorable in the prognostic sense for any type of therapy. The effectiveness of immunotherapy does not manifest itself immediately, sometimes it is necessary to wait 3-4 months, but the treatment should be constant, systematic and continuous, even after the effect is achieved.

One of the new methods of treating metastatic RCC is allogeneic embryonic stem cell transplantation. This type of therapy is just entering oncological practice and its effectiveness is not yet clear, although some sources claim that the positive response to transplantation is about 50%.

Radiation therapy for renal cell carcinoma is considered ineffective, atypical cells are resistant to radiotherapy, but it is used as a palliative method to reduce the severity of pain symptoms and improve the patient's quality of life. In addition, RT (radiation therapy) helps stabilize the condition of the skeletal system in case of bone metastasis and prevent tissue remineralization.

In general, kidney metastases are still treated surgically if their location does not prevent surgery. Surgical intervention remains the most effective method in the treatment of metastatic RCC as a means of neutralizing the focus of the process and is carried out in the following ways: •

• Resection, depending on the extent of the process, can be open or laparoscopic.
• Removal of the tumor along with the organ – nephrectomy.
• Cryoblation of malignant tumors under ultrasound control.
• Chemoembolization.
• Radiosurgery.

It should be noted that those oncology centers that are equipped with the CyberKnife robotic hardware complex give their patients twice the chance of survival. Radiosurgery is especially effective in stage I and II renal cell cancer, even in the presence of metastases. CyberKnife is capable of neutralizing almost any hard-to-reach tumor; its mechanism of action is a powerful beam of ionizing radiation that destroys all atypical cells. Radiosurgery is characterized not only by high precision and low-traumatic action during manipulations, but also by the fact that when neutralizing affected tissues, healthy areas remain intact and safe. If surgery is impossible due to the patient's serious condition and advanced stage of the disease, the following treatment methods are indicated:

1. Targeted therapy as one of the new methods for inoperable metastatic kidney cancer.
2. Symptomatic palliative treatment – in case of widespread metastasis.

Renal metastases are considered an unfavorable phenomenon, and the prognosis of treatment directly depends on their number, localization of secondary foci. According to statistics, the average five-year life expectancy is observed in 40% of patients after nephrectomy and complex, long-term treatment. A much smaller percentage of patients survive at stages III and IV of the process, but medical science does not stand still. Literally every year new, more advanced drugs and treatment methods appear, this gives hope that cancer will cease to be a terrible sentence and will be defeated.