Tumor lysis syndrome

As tumor lysis syndrome ( engl. tumor lysis syndrome ) refers to a potentially life-threatening condition that can occur during the rapid disintegration of tumors ( usually under chemotherapeutic treatment).

Causes, pathophysiology

Certain fast-growing tumors are relatively sensitive to chemotherapeutic treatment, ie be destroyed in a very short time, large quantities of tumor cells by the treatment with continuous chemotherapy. Thus many ingredients from inside the tumor cells are released into the bloodstream and can lead to a metabolic imbalance. The following substances are crucial for the development of these metabolic derailment:

• Uric acid, an end- degradation product of nucleic acids
• Phosphate
• Calcium - waste through loss of calcium phosphate.

If these substances are obtained in a short time in large amounts ( calcium decreases), it can come to metabolic imbalance and it comes especially to the injury of renal function, as the budget of those above-mentioned substances is regulated significantly on excretion by the kidney. The key is usually the uric acid which, when it is formed suddenly in large quantities, can not be excreted properly by the kidney, crystallizes in the kidneys and result in urate nephropathy ( uric acid salts of urates = ). In the worst case it comes to acute renal failure, which can lead to chronic dialysis.

In general, the risk of tumor lysis syndrome are particularly at fast-growing and chemotherapy- sensitive tumors. These include, first and foremost:

• Acute leukemia: acute lymphoblastic leukemia, acute myeloid leukemia
• Malignant lymphomas, particularly fast-growing lymphoma: Burkitt 's lymphoma, diffuse large cell lymphoma
• Non- small cell lung cancer

Prevention

For prophylaxis of tumor lysis syndrome, various measures can be taken:

• Intravenous infusions to help the kidneys are well flushed (this will be excreted via the kidneys substances diluted )
• Administration of allopurinol (inhibits uric acid formation)
• Urinary alkalinization by appropriate infusions or medications: in the alkaline range, the uric acid is mainly used as urate salt before and is much more soluble in water and can be better separated.

If a tumor lysis syndrome is feared that chemotherapy should be started slowly and carefully. In the above-mentioned leukemias and lymphomas is usually goes before so that you vorschaltet a relatively mild, so-called Vorphasetherapie, during which there is a relatively slow controlled tumor lysis. The drugs of Vorphasetherapie in lymphatic diseases are glucocorticoids ( " cortisone" ) and vincristine or low-dose cyclophosphamide.

Treatment

If a tumor lysis syndrome occurred only once, you have to deal with first and foremost acute renal failure and ensure a balance between the derailed blood ( see above). To treat the acute high uric acid levels, can rasburicase ( Fasturtec ®), a uric acid -degrading recombinant enzyme may be added (expensive therapy). Allopurinol should not be administered for acute renal failure.