11C-Acetate PET/CT in localized prostate cancer: a study with MRI and histopathologic correlation.

UNLABELLED: This work characterizes the uptake of (11)C-acetate in prostate cancer (PCa), benign prostate hyperplasia, and normal prostate tissue in comparison with multiparametric MRI, whole-mount histopathology, and clinical markers to evaluate the potential utility of (11)C-acetate for delineating intraprostatic tumors in a population of patients with localized PCa. METHODS: Thirty-nine men with presumed localized PCa underwent dynamic-static abdominal-pelvic (11)C-acetate PET/CT for 30 min and 3-T multiparametric MRI before prostatectomy. PET/CT images were registered to MR images using pelvic bones for initial rotation-translation, followed by manual adjustments to account for prostate motion and deformation from the MRI endorectal coil. Whole-mount pathology specimens were sectioned using an MRI-based patient-specific mold resulting in improved registration between the MRI, PET, and pathology. (11)C-acetate PET standardized uptake values were compared with multiparametric MRI and pathology. RESULTS: (11)C-acetate uptake was rapid but reversible, peaking at 3-5 min after injection and reaching a relative plateau at approximately 10 min. The average maximum standardized uptake value (10-12 min) of tumors was significantly higher than that of normal prostate tissue (4.4 ± 2.05 [range, 1.8-9.2] vs. 2.1 ± 0.94 [range, 0.7-3.4], respectively; P < 0.001); however, it was not significantly different from that of benign prostatic hyperplasia (4.8 ± 2.01 [range, 1.8-8.8]). A sector-based comparison with histopathology, including all tumors greater than 0.5 cm, revealed a sensitivity and specificity of 61.6% and 80.0%, respectively, for (11)C-acetate PET/CT and 82.3% and 95.1%, respectively, for MRI. The (11)C-acetate accuracy was comparable to that of MRI when only tumors greater than 0.9 cm were considered. In a small cohort (n = 9), (11)C-acetate uptake was independent of fatty acid synthase expression using immunohistochemistry. CONCLUSION: (11)C-acetate PET/CT demonstrates higher uptake in tumor foci than in normal prostate tissue; however, (11)C-acetate uptake in tumors is similar to that in benign prostate hyperplasia nodules. Although (11)C-acetate PET/CT is not likely to have utility as an independent modality for evaluation of localized PCa, the high uptake in tumors may make it useful for monitoring focal therapy when tissue damage after therapy may limit anatomic imaging methods.

What we thought we knew: African American males' perceptions of prostate cancer and screening methods.

This study applied the Health Belief Model in determining African American male's knowledge, attitudes and perceptions of prostate cancer and early detection methods. The ultimate value of the information assessed from this population was used to design specific theory-based, culturally relevant interventions which may decrease mortality in this high-risk population. Two focus groups were conducted with African-American men whose ages ranged from 38-80 years. After consenting to audio-taping, participants completed a survey questionnaire and viewed a culturally appropriate video on prostate cancer. Results indicate that, on average, the men believed in the efficacy of prostate cancer early detection methods. Study participants felt physicians did not adequately screen or suggest that they be screened for prostate cancer. Men between 40 and 50 years of age expressed concern about possible changes in their sex life if diagnosed with prostate cancer. Despite having limited knowledge of prostate cancer they considered a digital rectal examination to be embarrassing and uncomfortable. However, they were not opposed to having the procedure done.