A Workflow to Improve the Alignment of Prostate Imaging with Whole-mount Histopathology.

RATIONALE AND OBJECTIVES: Evaluation of prostate imaging tests against whole-mount histology specimens requires accurate alignment between radiologic and histologic data sets. Misalignment results in false-positive and -negative zones as assessed by imaging. We describe a workflow for three-dimensional alignment of prostate imaging data against whole-mount prostatectomy reference specimens and assess its performance against a standard workflow. MATERIALS AND METHODS: Ethical approval was granted. Patients underwent motorized transrectal ultrasound (Prostate Histoscanning) to generate a three-dimensional image of the prostate before radical prostatectomy. The test workflow incorporated steps for axial alignment between imaging and histology, size adjustments following formalin fixation, and use of custom-made parallel cutters and digital caliper instruments. The control workflow comprised freehand cutting and assumed homogeneous block thicknesses at the same relative angles between pathology and imaging sections. RESULTS: Thirty radical prostatectomy specimens were histologically and radiologically processed, either by an alignment-optimized workflow (n = 20) or a control workflow (n = 10). The optimized workflow generated tissue blocks of heterogeneous thicknesses but with no significant drifting in the cutting plane. The control workflow resulted in significantly nonparallel blocks, accurately matching only one out of four histology blocks to their respective imaging data. The image-to-histology alignment accuracy was 20% greater in the optimized workflow (P < .0001), with higher sensitivity (85% vs. 69%) and specificity (94% vs. 73%) for margin prediction in a 5 × 5-mm grid analysis. CONCLUSIONS: A significantly better alignment was observed in the optimized workflow. Evaluation of prostate imaging biomarkers using whole-mount histology references should include a test-to-reference spatial alignment workflow.

Indications, results and safety profile of transperineal sector biopsies (TPSB) of the prostate: a single centre experience of 634 cases.

OBJECTIVE: To describe a protocol for transperineal sector biopsies (TPSB) of the prostate and present the clinical experience of this technique in a UK population. PATIENTS AND METHODS: A retrospective review of a single-centre experience of TPSB approach was undertaken that preferentially, but not exclusively, targeted the peripheral zone of the prostate with 24-38 cores using a 'sector plan'. Procedures were carried out under general anaesthetic in most patients. Between January 2007 and August 2011, 634 consecutive patients underwent TPSB for the following indications: prior negative transrectal biopsy (TRB; 174 men); primary biopsy in men at risk of sepsis (153); further evaluation after low-risk disease diagnosed based on a 12-core TRB (307). RESULTS: Prostate cancer was found in 36% of men after a negative TRB; 17% of these had disease solely in anterior sectors. As a primary diagnostic strategy, prostate cancer was diagnosed in 54% of men (median PSA level was 7.4 ng/mL). Of men with Gleason 3+3 disease on TRB, 29% were upgraded and went on to have radical treatment. Postoperative urinary retention occurred in 11 (1.7%) men, two secondary to clots. Per-urethral bleeding requiring hospital stay occurred in two men. There were no cases of urosepsis. CONCLUSIONS: TPSB of the prostate has a role in defining disease previously missed or under-diagnosed by TRB. The procedure has low morbidity.

Live surgical education: a perspective from the surgeons who perform it.

OBJECTIVE: To evaluate the experience and views regarding live surgical broadcasts (LSB) among European urologists attending the European Association of Urology Robotic Urology Society (ERUS) congress in September 2012. MATERIALS AND METHODS: An anonymous survey was distributed via email inviting the participants of the ERUS congress with experience of LSB to share their opinions about LSB. The outcomes measured included; personal experience of LSB, levels of anxiety faced and the perceived surgical quality. The impact of factors, such as communication/team-working, travel fatigue and lack of specific equipment were also evaluated. RESULTS: In all, 106 surgeons responded with 98 (92.5%) reporting personal experience of LSB; 6.5% respondents noted 'significant anxiety' increasing to 19.4% when performing surgery away from home (P < 0.001). Surgical quality was perceived as 'slightly worse' and 'significantly worse' by 16.1% and 2.2%, which deteriorated further to 23.9% and 3.3% respectively in a 'foreign' environment (P = 0.005). In all, 10.9% of surgeons 'always' brought their own surgical team compared with 37% relying on their host institution; 2.4% raised significant concerns with their team and 18.8% encountered significantly more technical difficulties. Lack of specific equipment (10.3%), language difficulties (6.2%) and jet lag (7.3%) were other significant factors reported. In all, 75% of surgeons perceived the audience wanted a slick demonstration; however, 52.2% and 42.4% respectively also reported the audience wished the surgeon to struggle or manage a complication during a LSB. CONCLUSIONS: A small proportion of surgeons had significantly heightened anxiety levels and lower perceived performance during LSB, which in a 'foreign' environment seemed to affect a greater proportion of surgeons. Various factors appear to impact surgical performance raising concerns about the appropriateness of unregulated LSB as a teaching method. To mitigate these concerns, surgeons' performing live surgery feel that the operation needs to be well planned using appropriate equipment; with many considering bringing their own team or operating from home on a video link.

Novel approach to mapping of resistance mutations in whole genomes by using restriction enzyme modulation of transformation efficiency.

Restriction enzyme modulation of transformation efficiencies (REMOTE) is a method that makes use of genome restriction maps and experimentally observed differences in transformation efficiencies of genomic DNA restriction digests to discover the location of mutations in genomes. The frequency with which digested genomic DNA from a resistant strain transforms a susceptible strain to resistance is primarily determined by the size of the fragment containing the resistance mutation and the distance of the mutation to the end of the fragment. The positions of restriction enzyme cleavage sites immediately flanking the resistance mutation define these parameters. The mapping procedure involves a process of elimination in which digests that transform with high frequency indicate that the restriction enzyme cleavage sites are relatively far away from the mutation, while digests that transform with low frequency indicate that the sites are close to the mutation. The transformation data are compared computationally to the genome restriction map to identify the regions that best fit the data. Transformations with PCR amplicons encompassing candidate regions identify the resistance locus and enable identification of the mutation. REMOTE was developed using Haemophilus influenzae strains with mutations in gyrA, gyrB, and rpsE that confer resistance to ciprofloxacin, novobiocin, and spectinomycin, respectively. We applied REMOTE to identify mutations that confer resistance to two novel antibacterial compounds. The resistance mutations were found in genes that can decrease the intracellular concentration of compounds: acrB, which encodes a subunit of the AcrAB-TolC efflux pump; and fadL, which encodes a long-chain fatty acid transporter.