Tumor Lysis Syndrome 종양용해증후군 (TLS)
백혈병, 림프종과 같은 빠르게 자라는 암치료 직후 암세포가 사멸하면서 세포내 물질을 혈액내로 방출하여 생기는 증상. 횡문근 용해와 유사하게 고칼륨혈증, 과인산혈증, 저칼슘혈증, 고요산혈증, 질소혈증 등이 나타나 신장, 심장, 간의 장기 손상을 초래하고 발작, 부정맥, 사망에 이르게 될 수도 있다.
[네이버 지식백과] 종양용해증후군 [tumor lysis syndrome] (암용어사전)
Treating TLS
Before treatment begins, your healthcare team will determine if you have a risk of developing tumour lysis syndrome. The risk is based on:
- the type of cancer
- how far the cancer has progressed
- pre-existing conditions, such as poor kidney function, heart disease or high blood pressure
- lab tests
If you have a risk of developing TLS, your healthcare team can suggest ways to prevent it before you start cancer treatment. This usually includes making sure your body gets enough fluids. You may be given fluids through a needle in a vein, or intravenously. Fluids are usually given 24–48 hours before treatment starts and for several days after treatment is finished. While you are given fluids, the healthcare team will monitor how much urine you produce (urine output). It is important that you output 150–200 ml of urine every hour. They may prescribe a diuretic to maintain urine flow. Diuretics are drugs that help the body make urine.
Your healthcare team will do blood tests and watch for symptoms of TLS throughout treatment. If TLS develops, they may suggest the following measures to treat it.
Causes
TLS is more likely to develop when certain cancers or blood disorders are treated with chemotherapy. These cancers cause a high white blood cell count, have a high
- acute leukemia
- aggressive non-Hodgkin lymphoma
-
myeloproliferative disorders
- solid tumours such as hepatoblastoma and stage IV neuroblastoma
- cancers that cause poor kidney function before treatment starts
Tumour lysis syndrome usually occurs at the start of chemotherapy when a large number of tumour cells are destroyed. It can occur within a few hours of treatment, but it is most often seen 48–72 hours (2–3 days) after treatment starts.
Diagnosis
TLS should be suspected in patients with large tumor burden who develop acute kidney failure along with hyperuricemia (> 15 mg/dL) or hyperphosphatemia (> 8 mg/dL). (Most other acute kidney failure occurs with uric acid < 12 mg/dL and phosphate < 6 mg/dL). Acute uric acid nephropathy is associated with little or no urine output. The urinalysis may show uric acid crystals or amorphous urates. The hypersecretion of uric acid can be detected with a high urine uric acid - creatinine ratio > 1.0, compared to a value of 0.6–0.7 for most other causes of acute kidney failure.[citation needed]
Cairo-Bishop definition[edit]
In 2004, Cairo and Bishop defined a classification system for tumor lysis syndrome.[15]
- Laboratory tumor lysis syndrome: abnormality in two or more of the following, occurring within three days before or seven days after chemotherapy.
- uric acid > 8 mg/dL or 25% increase
- potassium > 6 meq/L or 25% increase
- phosphate > 4.5 mg/dL or 25% increase
- calcium < 7 mg/dL or 25% decrease
- Clinical tumor lysis syndrome: laboratory tumor lysis syndrome plus one or more of the following:
- increased serum creatinine (1.5 times upper limit of normal)
- cardiac arrhythmia or sudden death
- seizure
A grading scale (0–5) is used depending on the presence of lab TLS, serum creatinine, arrhythmias, or seizures.
Howard definition[edit]
In 2011, Howard proposed a refinement of the standard Cairo-Bishop definition of TLS accounting for 2 limitations:[2]
- Two or more electrolyte laboratory abnormalities must be present simultaneously to be considered related to TLS. In fact, some patients may present with one abnormality, but later another one may develop that is unrelated to the TLS (e.g., hypocalcemia associated with sepsis).
- A 25% change from baseline should not be considered a criterion since such increases are rarely clinically important unless the value is already outside the normal range.
Moreover, any symptomatic hypocalcemia should constitute clinical TLS.