CT guided liver biopsy was performed the next day after development of spontaneous TLS. Liver specimen was reviewed by the pathologist

with a preliminary diagnosis of poorly differentiated adenocarcinoma. Immunohistochemistry stains were positive for cytokeratin 7, cytokeratin 20, CDX2 and negative for HEP PAR 1, TTF 1, chromogranin, synaptophysin and PSAP. Based on these results, hepatocellular cancer (based on negativity for HEP PAR 1), colorectal carcinoma (based on www.selleckchem.com/products/epz005687.html positivity for cytokeratin 7), and lung cancers (based on negative chromogranin and synaptophysin) Inhibitors,research,lifescience,medical were considered to be unlikely. Further staining for cytokeratin 19 (please see Figure 2) and CA 19-9 was done. Tumor was strongly positive for cytokeratin 19 and minimally positive for CA 19-9. Based on the clinical picture, imaging studies and immunohistochemistry, cholangiocarcinoma was deemed to be the primary tumor (6,7). Unfortunately, the patient clinical course was complicated by the development of liver failure and ultimately death Inhibitors,research,lifescience,medical two days after liver biopsy. Family refused autopsy. Figure 2 Strongly positive immunostain for cytokeratin 19 (IHC 20×). Discussion TLS is a true oncological emergency

comprised of laboratory derangement of cellular metabolism, which can lead to acute renal impairment, cardiac rhythm disturbances, seizures and death (1). Laboratory manifestations of TLS Inhibitors,research,lifescience,medical include hyperkalemia (>6.0 mEq/L), hyperphosphatemia (>4.5 mg/dL), hyperuricemia (>8.0

mg/dL) and hypocalcemia Inhibitors,research,lifescience,medical (<7.0 mg/dL). TLS can be either spontaneous (without cancer targeted treatment) or therapy related (chemotherapy or radiation therapy). TLS is common in patients with rapidly proliferating hematological malignancies such as acute lymphocytic leukemia, Burkitt lymphoma and diffuse large B cell lymphoma (2,3). The predilection of TLS to hematological malignancies can be explained by their sensitivity to therapy and proliferative rates (3). The treatment consists of aggressive hydration, correction of electrolyte disturbances and uric acid lowering therapy (2,4). TLS is a rare occurrence Inhibitors,research,lifescience,medical in patients with solid tumors, which can be explained by differences Farnesyltransferase in proliferation rates and sensitivity to chemotherapy and/or radiation therapy (8). Furthermore, spontaneous TLS is even rarer event in patients with solid malignancies (8). Nevertheless, clinicians should keep in mind that patients with solid tumors may develop this potentially deadly syndrome. Based on the literature review it seems that patients with advanced and metastatic tumors may be at risk for TLS (8). Other potential risk factors might be the presence of elevated baseline creatinine and decreased renal function, elevated LDH, elevated phosphorus, elevated potassium and elevated uric acid. It is unclear whether liver metastasis represents an individual risk factor for the development of TLS or is a simply marker of advanced disease.