Prostate cancer detection: comparison of T2-weighted imaging, diffusion-weighted imaging, proton magnetic resonance spectroscopic imaging, and the three techniques combined.

BACKGROUND: Magnetic resonance (MR) imaging has been established as the best imaging modality for the detection, localization, and staging of prostate cancer on account of its high resolution of soft tissue and the possibilities of multiplanar and multiparameter scanning. PURPOSE: To evaluate T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), MR spectroscopy (MRS), and the combination of these three MR techniques in the diagnosis of prostate cancer, as correlated to histopathologic findings. MATERIAL AND METHODS: MR imaging, including T2WI, DWI, and MRS, was performed at 1.5T with a body coil combined with a spine coil in 42 cases. Diagnosis was confirmed by histopathology through systematic transrectal prostate biopsy. Apparent diffusion coefficient (ADC) maps were obtained with two b values (0 and 1000 s/mm(2)). The metabolic maps of 3D-MRS imaging were analyzed for the ratio of (Cho+Cre)/Cit in each sextant. All cases were evaluated by T2WI, DWI, and MRS, and then by the three methods combined. The statistical indicators and the receiver operating characteristic (ROC) curve analysis of each method were compared to the results of histopathology obtained by transrectal prostate biopsy. RESULTS: 15 of 42 cases were confirmed to be cancerous, and 27 of 42 cases were noncancerous. All the 252 sextants were confirmed by biopsies, including 201 benign sextants and 51 malignant sextants. The sensitivity and the specificity for the detection of prostate cancer were 88.2% and 67.2% for T2WI, as the cutoff was 3; 82.4% and 81.6% for DWI, as the cutoff was 4; 84.3% and 98.0% for MRS, as the cutoff was 5; and 96.1% and 96.5% for the combined T2WI+DWI+MRS, as the cutoff was 4. In the ROC analysis, the correlative areas under the ROC curves (Az) were 0.848+/-0.030, 0.860+/-0.033, and 0.961+/-0.016 for T2WI, DWI, and MRS, respectively, and 0.978+/-0.009 for the combination of T2WI+DWI+MRS. CONCLUSION: The accuracy of the detection of prostate cancer is increased through a combination of the three techniques. Moreover, MRS demonstrated higher accuracy compared with T2WI or DWI.

The transcription factor PU.1, necessary for B-cell development is expressed in lymphocyte predominance, but not classical Hodgkin's disease.

Hodgkin's disease (HD) is a lymphoproliferative disease of predominantly B-cell origin. However, the reasons for the incomplete development of the B-cell phenotype and lack of immunoglobulin expression in classical HD (cHD) have not been fully explained. We examined the expression of PU.1 in HD, an Ets-family transcription factor, which regulates the expression of immunoglobulin and other genes that are important for B-cell development. Immunohistochemistry for PU.1 was performed on 35 cases of cHD and 15 cases of lymphocyte predominance HD as well as 67 non-Hodgkin's lymphomas (NHL). Expression of PU.1 was studied by Western blotting in four cHD-derived cell lines and in five NHL cell lines. We also studied the expression of two additional B-cell transcription factors, B-cell-specific activator protein and Oct-2. Our results show a striking lack of PU.1 expression by neoplastic cells in cHD but not in lymphocyte predominance HD. Our study also confirmed that B-cell-specific activator protein but not Oct-2 is not expressed by cHD. Western blotting showed no PU.1 protein expression in the cHD-derived cell lines, with the exception of one cell line of putative monocyte/histiocyte origin. The lack of PU.1 protein expression in cHD likely contributes to the lack of immunoglobulin expression and incomplete B-cell phenotype characteristic of the Reed-Sternberg cells in cHD.

[The demographic future of the pharmacy profession (1990-2020)]. / L'avenir démographique de la profession pharmaceutique (1990-2020).

Training of pharmacists in France is regulated by a numerous clausus system. However, forecasting the number of active pharmacists in the future is not an easy task for various reasons: (i) after graduation, certain pharmacists do not become occupationally active; (ii) there are many types of pharmaceutical occupations, a pharmacist may leave an occupation for an other or enter an occupation long time after graduation; (iii) for the time being, the dynamics governing retirement, mortality and other occupation leaving processes have not been observed and analyzed. Based on certain sets of reasonable assumptions, the Centre de Sociologie et de Démographie Médicales has attempted to design scenarios for future development of French pharmaceutical manpower. If the student annual intake is kept at its current level (2,250), the number of active pharmacists registered with the Ordre des Pharmaciens would rose to 60,400-63,000 in the year 2000, and to 65,400-71,300 in the year 2010, from less than 53,000 in 1990. If the numerous clausus is immediately reduced to 1,500 (i.e. a cut of one third from the current level), the number of registered pharmacists would be 57,000-58,300 in 2000 and 57,500-61,000 ten years later. All these calculations are carried out with techniques of demographic projection. It remains to know what set of figures would be the most suitable to the future need of the nation regarding pharmaceutical manpower.