RT Journal Article SR Electronic T1 Brain Metastasis in a Patient with a Sarcomatoid Variant RCC with Well-controlled Extracerebral Metastases by Temsirolimus JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 3443 OP 3447 VO 32 IS 8 A1 NOBUYUKI KIKUNO A1 TAKAFUMI KENNOKI A1 HIRONORI FUKUDA A1 YUICHI MATSUMOTO A1 KUNIKO TSUNOYAMA A1 SHINICHI BAN A1 HIDEAKI SATOH A1 OSAMU RYOJI YR 2012 UL http://ar.iiarjournals.org/content/32/8/3443.abstract AB Background: The sarcomatoid variant of metastatic renal cell carcinoma (RCC) has often an aggressive course and a poor prognosis, particularly when accompanied with brain metastasis. Case Report: We describe the case of a patient with sarcomatoid variant RCC in whom brain metastasis was observed as a new lesion during treatment with temsirolimus, despite other extracerebral metastatic lesions being well-controlled and progression-free. Results: This discrepancy between the effectiveness of temsirolimus for extracerebral metastases and the simultaneous progression of brain metastases of RCC raises a concern that while vascular endothelial growth factor (VEGF)-targeted therapy may have clinical efficacy, it may also carry a risk for new brain metastases due to weakening of the structure of the blood brain barrier. Conclusion: This case indicates that computed tomography monitoring of the brain should be regularly performed during VEGF-targeted therapy in patients with sarcomatoid variant RCC, even if brain metastases are absent and extracerebral metastatic lesions are well controlled.