Tumor collapse syndrome is a symptom complex caused by the rapid destruction of a large number of malignant neoplasia cells. It usually occurs in the treatment of diseases of the blood system, less often – in the treatment of other oncological diseases. It is accompanied by metabolic disorders that cause the development of arrhythmia, bradycardia, seizures, disorders of consciousness, acute renal failure, diarrhea or constipation, nausea, vomiting, intestinal obstruction and other disorders of various organs and systems. It is diagnosed on the basis of symptoms and laboratory tests. Treatment – infusion therapy, symptomatic therapy, hemodialysis.
Information
Tumor collapse syndrome is an urgent condition that occurs during the conservative treatment of oncological diseases. It is most often diagnosed with acute lymphoblastic leukemias and lymphomas, less often with chronic leukemias and solid neoplasms of various localization. Tumor collapse syndrome is usually detected against the background of taking chemotherapy drugs or after completion of chemotherapy, less often observed during radiation therapy, in some cases develops spontaneously. It is accompanied by the occurrence of acute renal failure due to hyperuricemia. It poses a threat to the patient’s life, requires urgent correction. Treatment is carried out by specialists in the field of oncology, urology and intensive care.
Causes
Usually, the tumor collapse syndrome develops during the treatment of malignant neoplasms, which is due to the intensive destruction of tumor cells under the influence of chemotherapy drugs or radiation therapy. Leukemias and lymphomas, especially Burkitt’s lymphoma, have an initial tendency to such decay, which worsens after the start of treatment. The risk of developing tumor collapse syndrome increases with large neoplasms. Due to the relatively slow growth of blood vessels that do not keep up with the rapid proliferation of tumor cells, areas with insufficient blood supply often form in large tumors. These areas can necrotize both spontaneously and during therapy, traumatization of neoplasia or deterioration of blood circulation due to various factors (change in the patient’s condition, compression of a large feeding vessel, etc.).
In the syndrome of tumor decay, a large number of malignant cells containing phosphates and purine nucleotides are destroyed within a short period of time. Nucleotides are metabolized in the liver to form uric acid. The level of uric acid, phosphorus, potassium and some other substances in the blood sharply increases. Along with the listed disorders, lactic acidosis develops in the syndrome of tumor decay, due to impaired liver function due to damage by distant metastases and/or toxic effects of neoplasia decay products on organ cells.
There are disorders of acid-base and water-salt metabolism characteristic of the tumor decay syndrome, which have a negative impact on the activity of all organs and systems. All this happens against the background of exhaustion, metastatic lesions of lymph nodes and distant organs, leukocytosis, anemia, immune disorders and the previous accumulation of toxic metabolites in the blood, which further worsens the situation and can cause a sharp decompensation of the patient’s condition with tumor collapse syndrome.
Due to acidification of the blood, the pH of urine decreases. Uric acid crystals are deposited in the medulla, collecting tubules and renal tubules, preventing the filtration and excretion of urine. There is a decrease in renal clearance and a decrease in the filtration rate of the kidneys. Hyperphosphatemia, combined with hypocalcemia, is an additional factor aggravating renal dysfunction in tumor collapse syndrome. Due to a decrease in the level of calcium in the blood, the level of parathyroid hormone increases, which stimulates the excretion of phosphates from the body.
As a result of the action of this hormone, calcium salts are deposited in the kidney tissue of patients with tumor collapse syndrome, which also prevent the filtration and excretion of urine. Azotemia, oligo- or anuria occur, accompanied by the accumulation of toxic metabolic products in the body. Acute renal failure develops, which poses a threat to the life of a patient with tumor collapse syndrome. Hypocalcemia and hyperkalemia cause disorders of the cardiovascular system. Metabolic disorders entail violations of the functions of the central nervous system and the digestive system.
The release of enzymes by decaying cells, the formation of necrosis foci and a decrease in immunity contribute to the development of inflammation, the attachment of infection and subsequent suppuration in the decay zone of the neoplasm and adjacent tissues. Infectious complications further worsen the condition of a patient with tumor collapse syndrome, complicate the treatment process and can cause the development of sepsis. Another dangerous complication of this condition is the melting of a large vessel, accompanied by profuse bleeding.
Symptoms
The development of tumor collapse syndrome is accompanied by deterioration of the patient’s condition. Progressive weakness and hyperthermia occur. Dyspeptic disorders are noted: abdominal pain, nausea, vomiting, lack of appetite, constipation or diarrhea. When the central nervous system is affected, convulsions, paresthesia and disturbances of consciousness are observed. The defeat of the cardiovascular system in the syndrome of tumor collapse is manifested by bradycardia, arrhythmia and arterial hypotension. The development of renal insufficiency is indicated by oliguria or anuria. In patients with tumor collapse syndrome, jaundice of the skin often occurs due to impaired liver function.
Along with the general symptoms, there are manifestations due to the localization of the neoplasm. When breast cancer breaks down, large ulcers form. The syndrome of the collapse of a tumor of the stomach and intestines can be complicated by the melting of the vessel, followed by bleeding or perforation of the wall of the organ and the development of peritonitis. With the disintegration of lung cancer, bleeding, the occurrence of pneumothorax and the discharge of abundant putrefactive sputum are possible.
Diagnostics
The diagnosis is made on the basis of clinical manifestations, laboratory analysis data and instrumental studies. The first warning sign is usually a decrease in the amount of urine excreted. To detect the tumor collapse syndrome, the level of creatinine, uric acid, phosphates and calcium in the blood serum is determined. The condition of the liver is assessed taking into account the results of liver tests. If necessary, an ECG, CT and ultrasound of the kidneys are prescribed.
Treatment
Minor metabolic disorders are corrected on an outpatient basis. When signs of a developed tumor collapse syndrome appear, patients are hospitalized in the oncology or intensive care unit (depending on the severity of the condition and the severity of the disorders). With nausea and vomiting, antiemetics are prescribed. For constipation, laxatives and enemas are used. Antiarrhythmic drugs are used for arrhythmia. To correct water-salt and acid-base disorders, infusion therapy is performed in patients with tumor collapse syndrome. Diuresis control and correction of the drinking regime are carried out. In severe cases, patients are referred for hemodialysis. If necessary, analgesics and anti-inflammatory drugs are prescribed.
Prognosis and prevention
With timely initiation of treatment, the prognosis for tumor collapse syndrome is usually favorable. After correction of metabolic disorders, recovery of kidney function is observed. In the absence or late initiation of therapy of tumor collapse syndrome, a fatal outcome is possible due to acute renal failure, cardiac arrest or complications due to the collapse of the neoplasm (internal bleeding, peritonitis due to perforation of the wall of the hollow organ or severe infectious complications).
Measures to prevent the development of tumor collapse syndrome include drinking copious amounts 1-2 days before taking chemotherapy drugs, as well as regular monitoring of serum creatinine, uric acid, phosphates and calcium levels. In the first week of treatment, tests are performed daily. When clinical or laboratory signs of tumor collapse syndrome appear, laboratory tests are performed several times a day.