Radiation Oncology/Toxicity/Tumor Lysis Syndrome

Tumor Lysis Syndrome Usually occurs in bulky, rapidly growing tumors, which are sensitive to chemotherapy (e.g. high grade lymphoma, acute leukemia) Extremely uncommon as a result of RT in solid tumors Three cases in adult patients reported (medulloblastoma, metastatic breast cancer, NSCLC) All 3 cases had RT dose >= 3 Gy/fx Typically develops early during RT (within 4 days) Treatment with vigorous hydration Urinary alkalinization should probably be avoided, since it may predispose patient to urinary calcium phosphate precipitation, and subsequent worsening renal failure Korea Cancer Center, Seoul; 2008 19029410 -- "Fatal tumor lysis syndrome during radiotherapy for non-small-cell lung cancer." (Noh GY, PMID J Clin Oncol. 2008 Dec 20;26(36):6005-6. Epub 2008 Nov 24.) Case report. 52M with NSCLC, 10-cm central mass. RT started for SVC. After 2 fractions of 3 Gy, decrease in urine output, worsening dyspnea, LDH 3331 U/L, uric acid 8.9 mg/dl