c-KIT: potential predictive factor for the efficacy of sorafenib in metastatic renal cell carcinoma with sarcomatoid feature.

BACKGROUND: Vascular endothelial growth factor-targeted therapy has been standard care for metastatic renal cell carcinoma for years. However, little clinical experience on these agents in the treatment of sarcomatoid tumors has been documented. The aim of the present study was to detect the expression of c-KIT in the primary tumor of metastatic renal cell carcinoma with sarcomatoid feature, and to reveal its potential value of predicting the efficacy of sorafenib treatment and survival of the patients. PATIENTS AND METHODS: Seventeen patients were enrolled and treated with sorafenib as a second-line treatment after cytokine therapy. The expressions of c-KIT was tested immunohistochemically in the 17 specimens of primary renal tumors. The correlation between c-KIT status and treatment effect was compared. Univariate and multivariate analysis were employed to determine the survival difference between c-KIT-positive and c-KIT-negative patients. RESULTS: Twelve of 17 specimens (70.6%) were detected to be overexpressing c-KIT. c-KIT positive patients had higher disease control rate (75%) compared with c-KIT-negative patients (25%), P = .036. Median overall survival time was 92 weeks for c-KIT positive patients and 44 weeks for c-KIT negative patients, log rank χ(2) = 9.566, P = .002. Multivariate Cox regression model analysis only revealed number of metastatic organs and c-KIT as independent prognostic factors. CONCLUSION: Our findings suggest that c-KIT can be a potential predictive factor for metastatic renal cell carcinoma with sarcomatoid feature in treatment using sorafenib, and patients with positive c-KIT expression might have better responses and obtain longer overall survival time.

Tumor cytoreduction results in better response to androgen ablation--a preliminary report of palliative transurethral resection of the prostate in metastatic hormone sensitive prostate cancer.

OBJECTIVES: To investigate the oncologic influence of transurethral resection of the prostate (TURP) as a cytoreductive surgery in metastatic hormone sensitive prostate cancer (mHSPC), in the setting of continuous complete androgen blockade (CAB). MATERIALS AND METHODS: Medical histories of 146 consecutive Chinese males with newly diagnosed mHSPC, registered in our institution in 2006 and 2007, were reviewed. All of these patients received CAB as initial systematic therapy. Demographics and cancer control outcomes from 39 mHSPC patients who underwent TURP for a relief of bladder outlet obstruction were compared with those of the other 107 who received CAB only when they were still hormone-sensitive. Median follow-up was 15 months (3 to 27 months). RESULTS: Age at diagnosis, baseline PSA, and biopsy Gleason score were comparable between the 2 groups. Patients who underwent a TURP had lower PSA nadir (median 0.15 ng/ml vs. 0.82 ng/ml, P = 0.015) and longer time to PSA nadir (11.2 months vs. 6.4 months, P < 0.001). More patients in the non-TURP group developed hormone refractory prostate cancer (P = 0.007). The TURP group had a tendency towards longer disease-specific survival and overall survival (24.4 months vs. 24.1 months and 24.4 months vs. 22.9 months, respectively), though this did not reach statistical significance. CONCLUSIONS: TURP resulted in a better and more prolonged response to hormone therapy in mHSPC, with a trend towards positive influence in disease specific survival and overall survival. To date, our preliminary report is the first study regarding long-term survival of cytoreductive surgery in mHSPC, and further investigations are warranted.