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Publications (3)11.42 Total impact

  • Article: The predictive value of immunohistochemical markers in untreated Wilms' tumour: are they useful?
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    ABSTRACT: PURPOSE: This study reevaluates the potential role of different tumour markers as prognostic indicators in untreated nephroblastoma. METHODS: Expression of a broad panel of tumour markers was investigated by means of immunohistochemical analysis in 43 WT patients. Patients were treated by radical nephrectomy and had a mean follow-up of 11.9 years. RESULTS: Generally, all the tumour markers studied were expressed in normal kidney tissue and at variable levels in the three cell types of WT (blastema, epithelium and stroma). Immunoreactive blastemal (Bcl-X, Bcl-2 and CD44s) and epithelial (Bcl-X, Bcl-2 and MIB-1) cells were present in the majority of tumours. No correlation was found between their expression and pathological stages. Univariate analysis showed that blastemal WT-1, TGF-α, VEGF, MIB-1 and p27 Kip1 were indicative for clinical progression. In a multivariate analysis, WT-1 protein expression by blastemal cells was an independent prognostic marker for clinical progression. CONCLUSIONS: The blastemal WT-1, TGF-α, VEGF, MIB-1 and p27Kip1 expression correlate with clinical progression in untreated nephroblastoma. Therefore, their expression may be of value in identifying patients with a high propensity to develop distant metastases.
    World Journal of Urology 05/2011; · 2.41 Impact Factor
  • Article: Fine needle aspiration using improved agar microbiopsy is highly concordant with renal mass final diagnosis and subclassification.
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    ABSTRACT: Computerized tomography and ultrasound are usually sufficient for preoperative evaluation of renal masses greater than 5 cm. For renal masses less than 5 cm additional histological evaluation could improve diagnosis and treatment decisions. We investigated the concordance between an improved agar microbiopsy technique and conventional cytology for diagnosing renal tumors. We performed fine needle aspiration in 40 renal masses after nephrectomy using a 22 gauge needle, obtaining multiple blind aspirations from the tumor surrounded by Gerota's fascia. Four conventional smears were prepared from each aspiration. An alcohol Carbowax solution was drawn up in the syringe and expelled in a vial. The fluid in the vial was processed according to our modified agar microbiopsy method using an additional cycle of centrifuging the hot sediment mixed in agar. Histological sections were prepared for light microscopy and immunohistochemistry. Cytology smears and agar microbiopsy sections were evaluated by 2 pathologists blinded to the definitive histological diagnosis. The series consisted of 28 renal cell carcinomas, including 25 clear cell, 2 chromophobe and 1 papillary lesions, 7 urothelial cell carcinomas, 3 oncocytomas, 1 angiomyolipoma and 1 unclassified malignant tumor. Agar microbiopsy was concordant with the final histological diagnosis in 39 of 40 cases (correlation 0.98). Classic cytology was concordant with definitive histology in 21 of 40 cases (correlation 0.52). In 5 of 40 cases cytology identified malignancy but did not subtype the tumor correctly. Of the aspirates 15% contained too few diagnostic cells. Ex vivo fine needle aspiration using an improved agar microbiopsy block technique is highly concordant (98%) with the final diagnosis and subclassification of renal masses. Future validation using an in vivo pretreatment setting is needed to determine its clinical value.
    The Journal of urology 12/2009; 182(6):2590-3. · 4.02 Impact Factor
  • Article: In vivo uptake of [11C]choline does not correlate with cell proliferation in human prostate cancer.
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    ABSTRACT: Prostate cancer is the second leading cause of death from cancer among US men. Positron emission tomography (PET) with [(11)C]choline has been shown to be useful in the staging and detection of prostate cancer. The background of the increased uptake of choline in human prostate cancer is not completely understood. The aim of this study was to prospectively investigate the relationship between the [(11)C]choline uptake and the cell proliferation in human prostate cancer. Prostate cancer tissue from 18 patients who had undergone a radical prostatectomy for histologically proven disease was studied. An [(11)C]choline PET scan was performed prior to surgery. Post-prostatectomy specimens were prepared and stained with the antibody MIB-1 for Ki-67, which depicts proliferation. Two independent observers counted the amount of stained nuclei per specimen. Prostate cancer showed Ki-67 staining and high uptake of [(11)C]choline. Statistical analysis showed no significant correlation between [(11)C]choline uptake and Ki-67 staining (R=0.23; P=0.34). No significant relationships were found between the uptake of [(11)C]choline (SUV) and either preoperative PSA (R=0.14; P=0.55) or Gleason sum score (R=0.28; P=0.25). In vivo uptake of [(11)C]choline does not correlate with cell proliferation in human prostate cancer as depicted by Ki-67. Our results suggest that a process other than proliferation is responsible for the uptake of [(11)C]choline in prostate cancer.
    European journal of nuclear medicine and molecular imaging 07/2005; 32(6):668-73. · 4.99 Impact Factor