Kidney cancer: symptoms and diagnosis

Symptoms of kidney cancer

Clinical symptoms of kidney cancer are manifold. The triad of symptoms - hematuria, swelling and pain - occurs at the advanced stage of the disease. Much more often the disease is asymptomatic and is diagnosed accidentally due to the patient's referral to a doctor on another occasion, or during clinical examination, sometimes manifested by one or two symptoms from the triad.

One of the most common symptoms of kidney cancer is total hematuria. This symptom occurs in 60 - 88% of patients. The mechanism of hematuria in renal tumors has not been fully elucidated. The most common opinion is that intensive hematuria is a consequence of the destruction of blood vessels by a tumor. And the emergence of hematuria in kidney cancer, which do not communicate with the pelvis, is explained by a hemodynamic disorder in the kidney.

Hematuria in tumors has a number of specific features. It is always total, appears suddenly, often among full health or against a background of more or less intense pain in the kidney area. Sometimes after hematuria, a typical attack of renal colic develops, docking after the clots retreat. The emergence of acute pain following intensive hematuria is characteristic of renal tumors. In other diseases, also accompanied by hematuria (nephrolithiasis, nephroptosis, hydronephrosis), pain usually precedes haematuria. In addition, bleeding in these diseases is rarely intense and is usually not accompanied by the release of clots.

Hematuria can be detected with one act of urination or last for several hours or days, and then suddenly disappear. The next bleeding may occur in a few days, and sometimes in a few months or even years.

The periods between repeated hematuria tend to shorten. In view of the fact that hematuria is often profane in kidney cancer, it is often accompanied by urinary incontinence of blood clots. Quite often hematuria is the only symptom not accompanied by pain or dysuric phenomena, unless the latter are caused by a cluster of blood clots in the bladder. An acute retention of urine due to tamponade of the bladder can develop, which is eliminated after self-separation or evacuation of clots.

Thus, the characteristic features of hematuria in kidney cancer are a sudden onset, profuse, presence of clots, intermittent character, often painless course.

Pain is the second most common symptom of kidney cancer. According to various authors, a pain symptom occurs in 50% of patients. In this case the pain is dull and acute, constant and paroxysmal. Dull pain can be the result of the sprain or germination of the fibrous capsule of the kidney, rich in nerve endings, the pressure of the growing tumor node on adjacent organs, nerve trunks or lumbar roots. Dull pain can also be caused by the displacement and tension of the vessels of the renal peduncle.

Acute pain can occur as a result of a sudden increase in intraocular pressure in the presence of clots of the pelvis or ureter with blood clots. Hemorrhages in the renal parenchyma or tumor tissue can also be a cause of acute pain.

The third symptom in kidney cancer is a palpable tumor. This symptom is currently rare, due to the fact that small-sized kidney cancer is diagnosed with ultrasound. It should be noted that it is not always possible to determine the tumor upon palpation. The least accessible for palpation of tumors of the upper pole of the kidney, in which it is often possible to feel the unaltered lower pole as a result of the displacement of the kidney downwards.

There is no parallel between the size of the kidney cancer and the stage of the process. There may be distant metastases with a diameter of the primary tumor node not more than 2 to 3 cm.

Kidney cancer is often accompanied by symptoms that are not "urological", these are paraneoplastic symptoms. They can precede the classic signs of kidney cancer for several months, and sometimes years.

Among these symptoms, the leading place is fever, if it is the only symptom of the disease. An increase in body temperature in renal tumors can be observed in both the initial and the advanced stages of the disease. In the presence of necrotic and inflammatory processes in the tumor, an increase in temperature can be explained by absorption of the products of decay of kidney cancer, etc. In the initial stages, high temperature is either the result of intoxication, or the result of pyrogenic reaction to a foreign protein.

The nature of fever in kidney cancer is different, but more often it is permanent or intermittent. In connection with such a temperature, the patient is usually looking for a purulent focus, subjecting it to numerous studies and antibacterial therapy. And only when against a background of a long fever there is a hematuria or other symptoms of a cancer of a kidney, the patient direct to the urologist.

The most frequent symptom that accompanies fever in kidney tumors is elevated ESR. This may be the only sign of a kidney tumor, in connection with which patients are also subject to urological examination.

One of the most peculiar manifestations of the tumor process in the kidney is renal polycythemia - secondary erythrocytosis. Most often, the cause of erythrocytosis is the clear-celled cancer.

Secondary erythrocytosis is described not only in malignant, but also in benign tumors and kidney cysts, hydronephrosis, as well as in stenosis of the renal artery. The reason for the increase in the amount of hemoglobin and erythrocytes in kidney diseases is reactive, functional irritation of erythropoiesis. It is known that erythrocytosis develops due to increased production of erythropoietin by a tumor or kidney parenchyma.

The persistent disappearance of erythrocytosis after the removal of kidney cancer is a favorable prognostic sign. At the same time, the resumption of this symptom indicates either a relapse or a metastasis of the tumor.

Kidney cancer can be accompanied by arterial hypertension, according to A.Ya. Pytel (1966), in 15-20% of cases. The mechanism of hypertension in kidney tumors remains unclear. Some authors attach importance to endocrine disorders in the genesis of hypertension, others to the effect of sclerotic changes in blood vessels, the location of the tumor near the kidneys gates, and the possibility of production of a vasopressive substance by the tumor, as evidenced by normalization of pressure after tumor removal.

Kidney cancer is sometimes accompanied by hypercalcemia, which may be the only symptom of the disease, disappears after radical nephrectomy and may reappear upon metastasis or relapse of the tumor.

Immunological studies of tumor tissue in patients with renal adenocarcinoma and hypercalcemia revealed substances that do not differ in antigens from parathyroid hormone within the tumor. Kidney cancer, accompanied by hypercalcemia, quickly progresses and, as a rule, have a poor prognosis.

Sometimes the first symptom of kidney cancer is distant metastases (in the lungs, bones, brain, etc.). It should be noted that most often metastases as the first clinical manifestations of the disease are localized in the bone system and lungs.

Sometimes the kidney tumor first manifests itself as "uncharacteristic" metastases in organs such as the mammary gland, the wall of the bladder, the ureter wall, the larynx, the thyroid gland, the external auditory canal, the heart muscle, the frontal bone, the vaginal wall,

One of the important symptoms for kidney tumors is varicocele. It can be caused by the following reasons for kidney cancer: compression or germination of a renal vein tumor; compression of the inferior vena cava or directly one of the testicular veins with a tumor or metastatic nodes; thrombosis of the inferior vena cava; inflection of the renal vein as a result of displacement of the kidney downwards; a tumor thrombus in the renal vein. Under these conditions, the pressure in the renal or inferior vena cava increases, and collateral and venous outflow along the testicular vein of the corresponding side occurs with the development of varicose veins of the spermatic cord.

The frequency of varicocele in kidney tumors is different. This is usually a late symptom in the clinical course of the disease.

Other symptoms indicative of a disturbed venous outflow include symptoms resulting from acute and chronic thrombosis of the inferior vena cava. The tumor thrombus develops as a result of tumor germination into the renal vein and inferior vena cava, from which it can sometimes reach the heart.

Histological examination of thrombi extracted from the vulvar veins or inferior vena cava indicates that along with tumor cells, blood clots form part of the thrombus.

Acute thrombosis of the inferior vena cava is a rare phenomenon, characterized by a violent onset with a sharp deterioration in the general condition of the patient. At the same time there is a sudden severe disturbance of blood circulation in the lower extremities, the organs of the abdominal cavity and pelvis. If thrombosis is common, then severe violations of the kidney and adrenal gland function. Blockage of veins of both kidneys leads to anuria and rapid death. If the thrombosis develops gradually, the venous outflow begins to recover by collaterals and the patient suffers less.

With partial thrombosis of the inferior vena cava, the symptoms grow slowly, gradually. Edema of the lower extremities is an important sign that the lower hollow vein is blkbirovana tumor mass and the operability of kidney cancer is questionable.

The most characteristic symptom of chronic thrombosis of the inferior vena cava is edema of the lower limbs, which rises as the process spreads upward, from the front grasping the abdominal wall to the level of the navel, from behind to the lumbar region, sometimes to the base of the thorax. Often swelling spreads to the genitals.

Sometimes kidney cancer manifests itself as a clinical picture of an acute abdomen that occurs on the ground of acute bleeding when a severely dilated vein of the adrenal tissue ruptures or a massive hemorrhage into the tumor tissue. If the integrity of the fibrous capsule is broken, the blood is poured into the pericardial tissue, forming an extensive perineal hematoma.

The general condition of patients often remains a long time satisfactory and often does not correspond to the severity of the underlying disease. Symptoms such as general weakness, decreased appetite, cachexia are usually signs of a common process.

Diagnosis of kidney cancer

Diagnosis of tumors of the upper urinary tract is quite difficult, which is due, on the one hand, to the rarity of the disease and the lack of oncological alertness of doctors, on the other - the fact that the clinical and laboratory manifestations of kidney cancer are similar to those of other urological and oncological diseases.

Improvement of diagnostic methods has now led to the fact that the detected kidney cancer has small dimensions and is limited within the body, therefore, using physical methods of research is not found.

The leading role in the recognition of the tumor process in the kidney is currently played by ultrasound (ultrasound). The method is highly informative, does not require preliminary preparation, it is safe.

In the presence of a tumor, the contours of the kidney are deformed, and there are many echoes within the tumor. The use of a Doppler sensor allows the determination of hypervascularization, more characteristic of kidney cancer. Of great importance is the ultrasound investigation in the differential diagnosis of the tumor process from other pathological changes in the kidney. With the help of ultrasound scanning, the state of the zones of regional metastasis is determined.

X-ray computed tomography (CT) is the main diagnostic method for kidney cancer. Kidney cancer is defined as a node deforming the cortical layer of the kidney and its cavity or spreading beyond the body. The accuracy of the method is 95%. With the help of PCT it is possible to determine the spread of the tumor process to surrounding vessels.

Magnetic resonance imaging (MRI) is of great importance in the diagnosis of volumetric kidney formation. It is indicated to patients with severe renal dysfunction, with allergic reactions to iodine-containing contrast solutions, in the presence of contraindications to ionizing radiation. The advantage of MRI is the ability to diagnose a tumor thrombus and determine its upper limit.

Contraindications for MRI are claustrophobia, the presence of a patient in metal prostheses, surgical metal clips. An additional limitation is the high cost of the method.

Multispecial computed tomography (MSCT) makes it possible to evaluate not only the prevalence of the tumor process, but also the calyxal and pelvic system and vessels.

Angiography is currently performed only in cases where accurate information is required on the number of renal arteries, vascular architectonics of the kidney, and if suspicion of involvement of the main vessels is required.

Excretory urography allows us to clarify the functional and morphological features of the kidney affected by the tumor, as well as the state of the opposite kidney. This method allows one to suspect a volumetric process in the kidney, not allowing to solve the question of staging, so at present it is rarely used.

The algorithm for the examination of patients has changed: after detection of neoplasm with ultrasound, MSCT is performed, which allows to abandon excretory urography and complex vascular examination. Both MSCT and MRI allow us to judge the presence and extent of the tumor venous thrombus, and MRI with suppression of the signal from parainfury - on the invasion of the fibrous capsule of the kidney, which facilitates differential diagnosis of T1a, b and TZa disease stage.

Despite the enormous possibilities of tomography, in a number of cases (suspicion of benign tumor structure, unclear organ affinity, severe intercurrent background, etc.), it is necessary to establish the morphological structure of the neoplasm before the operation. This allows you to make only a biopsy, the informativeness of which reaches 90%. To increase the informativity of the biopsy, the definition of telomerase activity is used. The telomerase enzyme is a ribonucleoprotein complex that synthesizes the end sequences of DNA-telomeres. Telomeres protect the ends of chromosomes from enzymatic destruction, prevent the chromosomes from merging with each other and are necessary for doubling the genetic material during cell division. High activity of the enzyme is observed in the germinal, stem, and sexual cells of man, as well as in macrophages and leukocytes. In most somatic cells, telomerase activity is absent, although information about this enzyme is encoded in the DNA of all cells. During the malignant degeneration of the cell, telomerase is activated, which provides the malignant cell with the ability to unlimited number of divisions. Most malignant tumors are characterized by high telomerase activity. Kidney cancer is not an exception.

Laparoscopy can be used for a biopsy of kidney cancer. There is a large number of studies confirming the great diagnostic value of kidney biopsy in tumors. Visualization of the organ is possible not only through ultrasound scanning, but also with laparoscopic and retroperitoneoscopic access. Transperitoneal laparoscopic imaging of the neoplasm is performed and aspirate the contents of the tumor for cytological examination.

The most important laboratory parameters that should be determined in patients with kidney cancer are hemoglobin and ESR, which serve as prognostic factors, creatinine, which allows assessing the functional state of the kidneys, alkaline phosphatase, the increase of which may indicate the presence of metastases in the liver and bone, and Serum calcium in order to exclude hypercalcemia.

[1], [2], [3], [4], [5]