Quantitative Prostate MRI Analysis Following Fluvastatin Therapy for Localized Prostate Cancer - A Pilot Study.

PURPOSE: To assess the role of multi-parametric MRI (mpMRI) in assessment of tumor response to fluvastatin administered prior to radical prostatectomy. METHODS: Men with MRI-visible, clinically significant prostate cancer and due to be treated with radical prostatectomy were prospectively enrolled. mpMRI was performed at baseline and following 6-7 week of neoadjuvant oral statin therapy (40 mg fluvastatin, twice daily), prior to prostatectomy. MRI assessment included tumor size, T2 relaxation time, ADC value, K-trans (volume transfer constant), Kep (reflux constant), and Ve (fractional volume) parameters at the 2 time points. Initial prostate needle biopsy cores, prior to starting oral statin therapy, corresponding to site of tumor on radical prostatectomy specimens were selected for analysis. The effect of fluvastatin on tumor proliferation (marker Ki67) and on tumor cell apoptosis (marker cleaved Caspase-3, CC3) were analyzed and correlated with MRI findings. RESULTS: Nine men with paired MRI studies were included in the study. Binary histopathological data was available for 6 of the participants. No significant change in tumor size (P = 0.898), T2 relaxation time (P = 0.213), ADC value (P = 0.455), K-trans (P = 0.613), Kep (P = 0.547) or Ve (P = 0.883) between the time of biopsy and prostatectomy were observed. No significant change in tumor proliferation (%Ki67-positive cells, P = 0.766) was observed by immunohistochemistry analysis. However, there was a significant increase in tumor cell apoptosis (%CC3-positive cells, P = 0.047). CONCLUSION: mpMRI techniques may not be sufficiently sensitive to detect the types (or magnitude) of tumor cell changes observed following 6-7 weeks of fluvastatin therapy for prostate cancer.

Computerised tomography skeletal muscle and adipose surface area values in a healthy Caucasian population.

BACKGROUND: The analysis of computerised tomography (CT) images to provide body composition data has grown exponentially. Despite this, there remains limited published data defining the normal range of skeletal muscle area and adipose tissue area using CT. The aim of this study was to determine age- and sex-specific body composition values using CT at the level of the third lumbar vertebrae, in a Caucasian population with a healthy body mass index (BMI). In addition, we sought to develop threshold values for low skeletal muscle mass using these data. METHODS: We included 107 healthy Caucasian patients (46 males; 61 females) with a healthy BMI (18-25 kg/m2) for analysis. Body composition data were obtained from a single transverse CT image at the mid-third lumbar vertebrae using ImageJ software. Tissue segmentation was performed using Hounsfield unit thresholds of -29 to +150 for muscle and -190 to -30 for adipose tissue. RESULTS: The mean age of the study cohort was 47.8 ± 11.0 years (range 21-73) with a median BMI of 23.7 kg/m2 (interquartile range 22.3-24.8). Patients were sub-divided into age above or below 50 years. Cut-offs for low muscle quantity, representing two standard deviations below the young healthy population mean values, were 43.5 cm2/m2 for males and 30.0 cm2/m2 for females. CONCLUSIONS: Our data provide an insight into the distribution of skeletal muscle and adipose tissue surface area values measured on CT from a healthy Caucasian population. Our CT-derived cut-offs for low muscle quantity, based on international guidelines, are much lower than those previously suggested.

Initial experience using the rigid forceps technique to remove wall-embedded IVC filters.

INTRODUCTION: Severely tilted and embedded inferior vena cava (IVC) filters remain the most challenging IVC filters to remove. Heavy endothelialisation over the filter hook can prevent engagement with standard snare and cone recovery techniques. The rigid forceps technique offers a way to dissect the endothelial cap and reliably retrieve severely tilted and embedded filters. By developing this technique, failed IVC retrieval rates can be significantly reduced and the optimum safety profile offered by temporary filters can be achieved. We present our initial experience with the rigid forceps technique described by Stavropoulos et al. for removing wall-embedded IVC filters. METHODS: We retrospectively reviewed the medical imaging and patient records of all patients who underwent a rigid forceps filter removal over a 22-month period across two tertiary referral institutions. RESULTS: The rigid forceps technique had a success rate of 85% (11/13) for IVC filter removals. All filters in the series showed evidence of filter tilt and embedding of the filter hook into the IVC wall. Average filter tilt from the Z-axis was 19 degrees (range 8-56). Filters observed in the case study were either Bard G2X (n = 6) or Cook Celect (n = 7). Average filter dwell time was 421 days (range 47-1053). There were no major complications observed. CONCLUSION: The rigid forceps technique can be readily emulated and is a safe and effective technique to remove severely tilted and embedded IVC filters. The development of this technique across both institutions has increased the successful filter removal rate, with perceived benefits to the safety profile of our IVC filter programme.