Estudo Retrospectivo sobre a variação pós-operatória do escore de Gleason Do Adenocarcinoma Prostático e fatores correlacionados.

Introdução: Atualmente cerca de 23% dos cânceres diagnosticados no gênero masculino são Adenocarcinoma de Próstata (ACP). Devido ao comportamento indolente observado nos estágios iniciais do ACP, métodos de tratamento menos invasivos têm sido utilizados a fim de minimizar as comorbidades dos tratamentos convencionais. O Escore de Gleason (EG) é obtido após análise histológica da Biópsia Prostática por agulha (BX), e prediz de maneira isolada o prognóstico dos pacientes com ACP, sendo utilizado, associado a outras variáveis, na escolha da opção terapêutica do ACP. Estudos têm demonstrado variações pós-operatórias no EG em até 1/3 dos casos. Objetivo: Identificar a variação do EG do ACP pré e pós Prostatectomia Radical (PR), correlacionado com: volume da próstata; valor sérico pré-operatório do Antígeno Prostático Específico (PSA); idade; Densidade do PSA (PSAd). Método: Estudo transversal e retrospectivo de 279 casos submetidos a PR por ACP entre janeiro de 2008 e junho de 2013, avaliando a variação pós-operatória do EG, e realizando análise de correlação da elevação pós-operatória do EG com a idade, o volume da próstata, o PSA pré-operatório e a PSAd, de maneira contínua e categórica. Resultado: A média de idade, volume da próstata, nível sérico de PSA e PSAd foi respectivamente 63,8 anos, 8,8 ng/ml, 33,37 cm3 e 0,32 ng/ml/cm3. Foi observada variação pós-operatória do EG em 34% da amostra, com elevação e redução pós-operatória do EG em respectivamente 27% e 7% de todos os casos e elevação pós-operatória de 29% quando EG foi igual ou inferior a 6. A idade e o volume da próstata não apresentaram correlação na elevação pós-operatória do EG (p=0,42 e p=0,37). O valor sérico pré-operatório do PSA se correlacionou com a elevação pós-operatória do EG (p=0,007), com fator de proteção quando inferior a 4 ng/ml (OR 0,41 e p=0,05) e de causa quando maior que 10 ng/ml (OR 2,62 e p=0,0008). A PSAd também se correlacionou com a elevação pós-operatória do EG (p=0,002), com fator de proteção quando menor que 0,15 ng/ml/cm3 (OR 0,41 e p = 0,02) e de causa quando maior que 0,15 ng/ml/cm3 (OR 2,39 e p=0,02). Conclusão: Ocorreu variação do EG em 34% dos casos, sendo 27% de elevação do EG e 7% de redução do EG. Os valores de PSA e PSAd apresentaram correlação com a elevação pós-operatória do EG. Palavras Chave: Adenocarcinoma de Próstata; Escore de Gleason; Antígeno Prostático Específico. ABSTRACT Introduction: Currently about 23% of cancers diagnosed in males are prostate adenocarcinoma (PA). Because of the indolent behavior observed in the early stages of PA, less invasive treatment methods are being used in an attempt to minimize comorbidities related with conventional treatments. After prostate needle biopsy tissue (BX) and histological analysis, the Gleason score (GS) is obtained. The GS alone is able to predict the prognosis of patients with PA and is used, along with other variables, for choosing the therapeutic option. Studies have shown variations in the postoperative GS in up to one third of cases. Objective: Identify the variation of the GS in cases of PA before and after radical prostatectomy (RP) and correlate to prostate volume, preoperative serum value of Prostate-Specific Antigen (PSA), age and PSA density (PSAd). Method: A retrospective, cross-sectional study of 279 cases submitted to RP due to PA between January 2008 and June 2013, assessing the postoperative variation of the GS, and performing correlation analysis of postoperative GS elevation with age, prostate volume, the preoperative PSA and PSAd, in a continuous and categorical manner. Results: The mean age, prostate volume, serum PSA and PSAd were, respectively, 63.8 years-old, 8.8 ng/ml, 33.37 cm3 and 0.32ng/mL/cm3. Postoperative GS variation was observed in 34% of the cases, with 27% having higher and 7% having lower values. When the GS was 6 or lower, 29% of all patients presented with an increase in postoperative GS values. Patients age and prostate volume were not statistically significant in postoperative GS elevation (p = 0,42 and p = 0,37, respectively). Preoperative serum PSA value demonstrated correlation with postoperative elevation of GS (p = 0.007), as a protection factor when less than 4 ng/mL (OR 0.41, p = 0.05) and as a causal factor when greater than 10 ng/mL (OR 2.62, p = 0.0008). The PSAd also proved to be related to postoperative elevation of the GS (p = 0,002), as a protection factor when less than 0,15 ng/mL/cm3 (OR 0,41 and p = 0,02) and as a causal factor when greater than 0,15 ng/mL/cm3 (OR 2,39 and p = 0,02). Conclusion: GS variation occurred in 34% of all cases, with 27% of patients having higher scores and 7% having lower scores. The high PSA value and the PSAd were associated with postoperative increase of GS values. Keywords: Prostate Adenocarcinoma; Gleason score; Prostate-Specific Antigen

Magnetoconductance anisotropy of a polymer thin film at the onset of metallicity

Thin films of poly(2,5-bis(3-dodecyl-2-yl)-thieno[3,2-b] thiophene) (C12-PBTTT) polymer under electrolyte gating and doping are investigated as model systems for organic thin films devices approaching the metallic side of a metal-insulator (M-I) transition. For the most doped samples, with an estimated density reaching 8 x 10(20) cm(-3) holes and a conductivity exceeding 1000 S cm(-1), a positive high-field magnetoconductance is found in a limited temperature range window and only when the field is perpendicular to the sample plane. This signature of weak localization, combined with indications of finite zero-temperature conductivity, allows us to identify delocalized metallic-like transport in these thin films, even though the conductivity decreases when cooling down the samples

High performance platinum contacts on high-flux CdZnTe detectors

The need for direct X-ray detection under high photon flux with moderate or high energies (30–100 keV range) has strongly increased with the rise of the 4th Generation Synchrotron Light Sources, characterised by extremely brilliant beamlines, and of other applications such as spectral computed tomography in medicine and non-destructive tests for industry. The novel Cadmium Zinc Telluride (CZT) developed by Redlen Technologies can be considered the reference material for high-flux applications (HF-CZT). The enhanced charge transport properties of the holes allow the mitigation of the effects of radiation induced polarization phenomena, typically observed in standard CZT materials (LF-CZT) under high photon flux. However, standard LF-CZT electrical contacts led to inacceptable high dark leakage currents on HF-CZT devices. In this work, a detailed study on the characteristics of new optimized sputtered platinum electrical contacts on HF-CZT detectors is reported. The results from electrical and spectroscopic investigations, showed the best performances on HF-CZT detectors with platinum anode, coupled with both platinum or gold cathode. The morphology, structure, and composition of Pt/CZT contact have been analysed by means of Transmission Electron Microscopy (TEM) on microscopic lamellas obtained by Focused Ion Beam (FIB), highlighting the presence of CdTeO3 oxide at the metal semiconductor interface

Potentialities of High-Resolution 3-D CZT Drift Strip Detectors for Prompt Gamma-Ray Measurements in BNCT

Recently, new high-resolution cadmium–zinc–telluride (CZT) drift strip detectors for room temperature gamma-ray spectroscopic imaging were developed by our group. The CZT detectors equipped with orthogonal anode/cathode collecting strips, drift strips and dedicated pulse processing allow a detection area of 6 × 20 mm2 and excellent room temperature spectroscopic performance (0.82% FWHM at 661.7 keV). In this work, we investigated the potentialities of these detectors for prompt gamma-ray spectroscopy (PGS) in boron neutron capture therapy (BNCT). The detectors, exploiting the measurement of the 478 keV prompt gamma rays emitted by 94%7Li nuclides from the10B(n, α)7Li reaction, are very appealing for the development of single-photon emission computed tomography (SPECT) systems and Compton cameras in BNCT. High-resolution gamma-ray spectra from10B samples under thermal neutrons were measured at the T.R.I.G.A. Mark II research nuclear reactor of the University of Pavia (Italy)

Optimization of quasi-hemispherical CdZnTe detectors by means of first principles simulation

In this paper we present the development of quasi-hemispherical gamma-ray detectors based on CdZnTe. Among the possible single-polarity electrode configurations, such as coplanar, pixelated, or virtual Frisch-grid geometries, quasi-hemispherical detectors are the most cost-effective alternative with comparable raw energy resolution in the high and low energy range. The optimal configuration of the sensor in terms of dimension of the crystals and electrode specifications has been first determined by simulations, and successively validated with experimental measures. Spectra from different sources have been acquired to evaluate the detectors performances. Three types of detectors with different CZT volumes have been fabricated, namely 10 × 10 × 5 mm3, 15 × 15 × 10 mm3 and 20 × 20 × 10 mm3. In the case of 10 × 10 × 5 mm3 crystals, the optimum pixel size determined by our simulation tool was confirmed by experiments: the best spectroscopic resolution of 1.3% at 662 keV has been found for a 750 μm diameter pixel detector. The best energy resolution values obtained for the 15 × 15 × 10 mm3 and 20 × 20 × 10 mm3 detectors were respectively 1.7% and 2.7% at 662 keV

Recent advances in the development of high-resolution 3D cadmium zinc telluride drift strip detectors

In the last two decades, great efforts have been made in the development of 3D cadmium-zinc-Telluride (CZT) detectors operating at room temperature for gamma-ray spectroscopic imaging. This work presents the spectroscopic performance of new high-resolution CZT drift strip detectors, recently developed at IMEM-CNR of Parma (Italy) in collaboration with due2lab (Italy). The detectors (19.4 mm × 19.4 mm × 6 mm) are organized into collecting anode strips (pitch of 1.6 mm) and drift strips (pitch of 0.4 mm) which are negatively biased to optimize electron charge collection. The cathode is divided into strips orthogonal to the anode strips with a pitch of 2 mm. Dedicated pulse processing analysis was performed on a wide range of collected and induced charge pulse shapes using custom 32-channel digital readout electronics. Excellent room-Temperature energy resolution (1.3% FWHM at 662 keV) was achieved using the detectors without any spectral corrections. Further improvements (0.8% FWHM at 662 keV) were also obtained through a novel correction technique based on the analysis of collected-induced charge pulses from anode and drift strips. These activities are in the framework of two Italian research projects on the development of spectroscopic gamma-ray imagers (10-1000 keV) for astrophysical and medical applications