In a case of suspected metastases or vena caval involvement, additional studies such as bone scintigraphy (14 patients, 9%), skeletal radiography

(17 patients, 11%), magnetic resonance imaging (MRI) (11 patients, 7%) or cavography (3 patients, 2%) were performed. The study was approved by the local ethical board. Tumour samples and TLR9 immunostaining The tumour samples were routinely fixed in 10% buffered formalin and embedded in paraffin. The histological diagnosis was confirmed by reviewing the haematoxylin and eosin (H & E) stained original sections simultaneously by two pathologists. The tumours were re-classified and graded according to the WHO classification [21]. The most representative block of the tumour was selected and cut into 3 μm thick sections, into multi-tissue blocks which were mounted onto precoated slides. Tissue sections were then NU7441 deparaffinized in xylene, rehydrated in descending ethanol series and Alvocidib in vivo washed in phosphate buffered saline (PBS). Expression of TLR9 was analyzed by using a mouse monoclonal anti-human TLR9/CD289 (Img-305A, clone 26C593.2, Imgenex, San Diego, California, USA, dilution 1:200) antibody, as previously shown by us [13, 22]. learn more In order to enhance the immunoreactivity, the sections were incubated

in a Tris-EDTA buffer (pH 9.0) and boiled. Endogenous peroxidase activity was eliminated by incubation in hydrogen peroxide and absolute methanol. The bound antibodies were visualized using Envision Detection System (K500711; Dako Denmark A/S). DAB (diaminobenzidine) was used as a chromogen. A multitissue block containing breast cancer samples and normal cervical tissue was used as a positive control. Scoring of TLR9 immunoreactivity Cytoplasmic TLR9 immunoreactivity was initially scored according to four cytoplasmic staining intensities: MYO10 negative (0), weak (1), moderate (2) or strong (3) [13, 22]. For further statistical analyses, the negative samples (score 0) were compared with the positive ones

(scores 1 to 3). Immunohistochemical staining was evaluated simultaneously by two observers (PH and MHV) who were blinded to the clinical data and a consensus on the staining intensity was reached. Statistical analyses The software SPSS for Windows 15 (Chicago, IL) was used for statistical analyses. Associations between factors, including clinicopathological variables and TLR9 immunostaining patterns, were assessed by the χ2 test, or the Fisher’s exact test in the case of low expected frequencies. Survival rates were calculated using the Kaplan-Meier method and the statistical significance between groups was analysed using the log-rank test. Hazard ratio (HR) was assessed by Cox univariate analysis. Renal cell carcinoma-specific survival was calculated from the date of diagnosis to death from RCC or the last day of follow-up. Deaths due to intercurrent causes were censored.