POD-6.12: Progression Free Survival in Patients with Metastatic and Recurrent Renal Cancer Treated with Sorafenib: Single Center Experience

PODIUM SESSIONS

comes comparable with more mature laparoscopic series.

lower levels of plasma adiponectin, a potential tumor suppressor, in RCC.

POD-6.11 Computerized Tomography Measurement of Visceral Adiposity Predicts Plasma Adiponectin Levels and Presence of Metastatic Disease in Patients with Clear Cell Renal Cell Carcinoma Kapoor A, Chatterjee S, Kleinmann N, Pinthus J McMaster University, Hamilton, Canada

POD-6.12 Progression Free Survival in Patients with Metastatic and Recurrent Renal Cancer Treated with Sorafenib: Single Center Experience Kapoor A, Chatterjee S, Pinthus J, Hotte S, Kleinmann N McMaster University, Hamilton, Canada

Introduction and Objectives: Obesity is a risk factor for renal cell carcinoma (RCC). A commonly used definition of obesity according to body mass index (BMI) is inaccurate. We have recently shown that plasma levels of adiponectin, a hormone secreted solely by adipocytes, inversely correlates to adverse prognostic factors in clear cell RCC. BMI had no effect on these factors. The purpose of this study was to develop a quantitative method of measuring visceral obesity and to correlate it to adiponectin levels and disease characteristics. Materials and Methods: Blood samples were collected pre-operatively from a cohort of 25 patients (11 with metastatic disease) all confirmed to have clear cell RCC at various stages. Visceral and peripheral fat content was measured using preoperative CT. Three representative slices were analyzed, the top of L2 vertebral body, umbilicus and the anterior superior iliac spine. Each standardized image was digitally analyzed and tissue at fat density was extracted to create a composite. This image was separated into visceral and subcutaneous components and the number of pixels was counted in each image. The three slices were then digitally summed to create a surrogate score of visceral and peripheral fat. This score was correlated to plasma adiponectin levels, tumor size, grade, presence of metastasis and BMI. Results: Using linear regression analysis, plasma adiponectin correlated inversely with the size of the tumor (P⬍0.01) but not with BMI. BMI correlated strongly with CT total fat and peripheral fat measurements (P⬍0.01) but not visceral fat measurement. Similarly, visceral obesity correlated inversely with plasma adiponectin levels (p⫽0.04) and with the presence of metastasis (p⫽0.03 by logistic regression) but not with other prognostic factors. Conclusions: Using a novel and easily reproducible method to quantify adiposity, we have shown that visceral obesity correlates with aggressive disease and

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Introduction and Objectives: Treatment of metastatic renal cell carcinoma (RCC) with sorafenib was previously shown to prolong progression free survival (PFS) with a median of 5.5 months. One of the advantages of using sorafenib is a relatively tolerable side effect profile. We examined our own experience with sorafenib as first line treatment of metastatic RCC in a heterogonous patient population, including patients with brain and bone metastases. Materials and Methods: We analyzed PFS defined as increased in size of target lesion or appearance of new metastases. Twenty-one patients with metastatic RCC were treated with oral sorafenib (400mg bid administered in 4-week cycles for the first 24 weeks and in 8-week cycles thereafter). Follow up consisted of four-weekly appointments with blood work and physical exams, quarterly or/as needed CT and bone scans, and ranged from 23-85 weeks (median 54 weeks). Soft tissue metastases were defined as within the lungs or liver (n⫽12). Two patients had brain metastases, five had bone metastases and two had local recurrence in the nephrectomy bed. Nine patients presented initially with metastatic tumor and 7 underwent cytoreductive nephrectomy. Eleven patients underwent therapeutic nephrectomy for localized disease. Results: The median PFS was 8.4 months (range 1.2-59 months). Four patients (19%) were progression free at last follow-up (median 12.75 months). Median PFS for patients with soft tissue metastases vs. patients with brain or bone metastases was 8.7 vs 6.1 months, respectively, with no statistically significant difference. Median PFS for patients with solitary vs. multiple metastases was 12.25 vs. 8.75 months, respectively. Durable PFS greater than 1 year was observed in 24% of patients. Stage, grade, age or gender did not predict PFS. During a follow-up period of up to 85 weeks, 7 (33%) death were recorded. All patients had some degree of side effects, most commonly gastro intestinal (81%), skin reaction (76%), fatigue (76%), and cardiovascular (57%). How-

ever, none of them had to stop therapy. Four patients who progressed were switched to sunitinib. Conclusions: Treatment of patients who have heterogonous and diverse metastatic RCC with sorafenib can achieve a median PFS of 8.4 months with frequent but tolerable side effects.

POD-6.13 Serum Amyloid Alpha 1: Potential Marker for Renal Cell Carcinomas? Junker K, Georgi C, Walter M, Pilchowski R, Steiner T, Schubert J Department of Urology, FriedrichSchiller-University, Jena, Germany Introduction and Objectives: Until now, no serum biomarkers are available for detection or monitoring of patients with renal cell carcinomas (RCC). Using ProteinChip technology, we identified Serum amyloid alpha 1 (SAA-1) as one of the relevant proteins which are significantly elevated in serum from patients with clear cell RCC. Based on these data, the aim of this study is to define the clinical value of SAA-1 for diagnosis, prognosis and therapy monitoring. Materials and Methods: Serum samples from 32 healthy controls, 62 patients with clear cell RCC, 28 patients with papillary RCC, 11 patients with chromophobic RCC, 14 patients with oncocytomas as well as 54 patients with bladder or prostate cancer were analyzed by a specific ELISA test for SAA. Furthermore, serum samples from 28 patients obtained preoperatively and after surgery (day 1 and day 7-10) were included. SAA was analyzed in 47 patients under immune-chemotherapy. All analyses were performed twice. For statistical analysis, the Mann-Whitney-U test was used. Results: Serum concentrations of SAA-1 were significantly elevated in patients with clear cell RCC (mean 57.8␮g/ml), papillary RCC (35.2␮g/ml), chromophobic RCC (28.3␮g/ml) and oncocytoma (17.3␮g/ml) compared to healthy controls (4.0␮g/ml). Furthermore, SAA-1 was notably increased in metastatic clear cell and papillary tumor patients compared to the non-metastatic tumor patients. In contrast to patients with protstate cancer, bladder cancer patients showed also a significantly higher level of SAA. In patients under combination therapy with IL-2, IFN and 5-FU, we found lower levels of SAA in patients with response. Furthermore, SAA was decreased in samples obtained after therapy compared to that prior therapy. Surgical intervention leads to a strong in-

UROLOGY 72 (Supplement 5A), November 2008