Immunological microenvironment in prostate cancer: high mast cell densities are associated with favorable tumor characteristics and good prognosis

BACKGROUND: Number of intratumoral mast cells predicts survival in various cancers. The prognostic significance of such mast cells in surgically treated prostate cancer is unknown. METHODS: Mast cell densities were determined in prostate cancer samples of more than 2,300 hormone-naïve patients using a tissue microarray format in correlation with clinical follow-up data. Mast cells were visualized immunohistochemically (c-kit). All patients were homogeneously treated by radical prostatectomy at a single institution. RESULTS: Mast cells were present in 95.9% of the tumor samples. Median mast cell number on the tissue spot was 9 (range: 0-90; median density: 31 mast cells/mm(2)). High mast cell densities were significantly associated with more favorable tumors having lower preoperative prostate-specific antigen (P = 0.0021), Gleason score (P < 0.0001) and tumor stage (P < 0.0001) than tumors with low mast cell densities. Prostate-specific antigen recurrence-free survival significantly (P = 0.0001) decreased with decline of mast cell density showing poorest outcome for patients without intratumoral mast cells. In multivariate analysis mast cell density narrowly missed to add independent prognostic information (P = 0.0815) for prostate-specific antigen recurrence. CONCLUSION: High intratumoral mast cell density is associated with favorable tumor characteristics and good prognosis in prostate cancer. This finding is consistent with a role of mast cells in the immunological host-defense reaction on prostate cancer. Triggering mast cell activity might expand immunotherapeutic strategies in prostate cancer.

Pelvic floor stimulation: what are the good vibrations?

OBJECTIVE: The aim of this study was to determine if two different whole body vibration, sinusoidal vibration (SV) and stochastic resonance vibration (SRV), using various intensities lead to a reactive activation of pelvic floor muscles. STUDY DESIGN: We compared the pelvic floor muscle response of a healthy control group with that of a post partum group with weakened pelvic floor contraction. Activation effects of stochastic resonance vibration and sinusoidal vibration with six increasing vibration intensities were investigated using pelvic floor EMG and compared to activity during rest and maximum voluntary contraction. RESULTS: Both whole body vibration systems were able to activate pelvic floor muscles significantly depending on vibration intensity. Generally, the SRV achieved a significantly higher activation than maximum voluntary contraction, especially in women post partum and using a frequency of 6-12 Hz. CONCLUSION: SRV, compared to SV, leads to higher pelvic floor muscle activation in subjects with weakened pelvic floor muscles and achieves higher pelvic floor activation than maximum voluntary contraction alone. Neurourol. Urodynam. 28:405-410, 2009. (c) 2009 Wiley-Liss, Inc.