**Author details**

treated with targeted agents were analyzed. Both univariate and multivariate linear regres‐ sion analyses revealed that only the initial tumor size was associated with the rate of reduc‐

Abel et al. [32] reported that early 10% decrease in tumor diameter of the primary tumor was predictive of improved overall survival in patients with metastatic renal tumor treated with sunitinib. In 75 consecutive treatment-naive patients, median overall survival time for patients without minor primary tumor response, with minor primary tumor response after 60 days, and with early minor primary tumor response was 10.3, 16.5, and 30.2 months, re‐ spectively. On multivariate analysis, early minor response was an independent predictor of

High visceral fat area could be a predictive biomarker from shorter survival in patients giv‐ en first-line antiangiogenic agents including sunitinib for metastatic renal tumors [33]. In 113 study population, 46 patients received sunitinib as first-line therapy. Visceral fat area was measured retrospectively on the available CT scans performed before sunitinib initiation at the level of the umbilicus with the patient in the supine position. ImageJ software was used to measure pixels with densities in the -190 Hounsfield units to -30 Hounsfield units range to delineate the visceral compartment and to compute the cross-sectional area of each in cm2

On multivariate analysis, high visceral fat area was independently associated with shorter time to progression and overall survival. Visceral fat area measured before starting first-line targeted therapy is likely to be a simple predictive biomarker in patients with metastatic re‐

Finally, hyponatremia seem to represent significant predictive factor for cancer-specific sur‐ vival in metastatic renal tumors treated with targeted therapy as first-line therapy [34]. A total of 87 patients treated with targeted therapy including sunitinib, severe (≤ 134 mEq/L) and mild (135-137 mEq/L) hyponatremia was shown to be significantly associated with can‐ cer-specific survival time (*P* = 0.001 and 0.013, respectively). In 38 patients treated wth suni‐ tinib, 4 patients (10.5%) developed severe hyponatremia and 8 patients (21.1%) developed mild hyponatremia. Hyponatremia could be easily and readily determined and might be an

Candidate biomarkers to predict response to sunitinib have been shown. Among clinical factors, CRP is a significant independent prognostic indicator for sunitinib. Severe adverse events, hypertension and hypothyroidism also recognized as biomarkers of favorable efficacy. Addi‐ tionally, tumor enhancement, SUVmax on FDG/PET-CT, tumor size, visceral fat area and hypo‐ natremia have been revealed clinical significance of sunitinib responses. Although further investigation will be required, these biomarkers can be utilized to measure therapeutic re‐ sponse and design treatment strategies for advanced renal tumors treated with sunitinib.

tion in individual tumors (*P*< 0.001) [31].

improved overall survival (*P* = 0.031) [32].

nal tumor [33].

40 Renal Tumor

**4. Conclusions**

important prognostic factor [34].

Tetsuo Fujita\* , Masatsugu Iwamura, Kazumasa Matsumoto and Kazunari Yoshida

\*Address all correspondence to: tfujita@cd5.so-net.ne.jp

Department of Urology, Kitasato University School of Medicine, Japan
