RESUMEN
PURPOSE: The purpose of this study was to determine the accuracy of manual semi-automated and volumetric measurements to assess prostate cancer volume on multiparametric magnetic resonance imaging (MP-MRI) using whole-mount histopathology for validation. MATERIALS AND METHODS: We evaluated 30 consecutive men (median age, 65.7 years; interquartile range [IQR], 61.5-70.9 years) with a median prostatic specific antigen of 8.5ng/dL (IQR, 5.5-10.5ng/dL), who underwent MP-MRI before radical prostatectomy. Index tumor volume was determined prospectively and independently on the basis of MRI and whole-mount section volumetric assessment using the maximum histologic diameter (MHD) and the histologic volume (HV). The MRI index tumor volume was determined by two independent radiologists using a single measurement of the maximum tumor dimension (MTD), a simplified MR ellipsoid volume (MREV) calculation and a MR region of interest volume (MROV) segmentation displayed by a commercially available OsiriX®. MTD was compared to MHD, whereas MREV and MROV were compared to HV. RESULTS: Thirty index lesions (median HV, 1.514 cm3; IQR, 0.05-3.780 cm3) were analyzed. The MREV, MROV and HD were significantly correlated with each other (r>0.5). Inter-observer agreement for measurements was good for each method (r>0.780). The MTD was the best predictor of maximum histologic diameter (r=0.980 and 0.791) and had an excellent inter-variability correlation (P<0.0001). CONCLUSION: Prostate cancer histologic volume can be assessed using MREV or MROV with a good accuracy and low inter-observer variability. MTD has the lowest inter-observer variability and provides best degrees of correlation with MHD. MTD should be used on MRI for selecting and following patients for active surveillance and staging before focal treatment of prostate cancer.
Asunto(s)
Imagen por Resonancia Magnética , Próstata/diagnóstico por imagen , Próstata/patología , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Carga Tumoral , Anciano , Automatización , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios RetrospectivosRESUMEN
The synthetic malaria vaccine SPf 66 has been shown to be safe, immunogenic and effective in trials performed with controlled groups naturally and experimentally exposed to the disease. In order to continue the trials in open populations, it was necessary to standardize the vaccination characteristics. We have performed four field trials with soldier volunteers with the aim, among others, of defining the number of doses required, the intervals between applications, the protein concentration, and the adjuvant to be used. In these trials, the vaccinated individuals' immune responses were evaluated by assaying anti-SPf 66 antibody titres, in vitro growth inhibition of the P. falciparum parasite, and the vaccinees' capacity to recognize P. falciparum native proteins. From these results we conclude that the best vaccination schedule, for adults, is three doses administered subcutaneously on days 0, 30 and 180, each containing 2 mg of the synthetic polymerized petide SPf 66 adsorbed to alum hydroxide.