Fusion of Magnetic Resonance Imaging and Real-Time Elastography to Visualize Prostate Cancer: A Prospective Analysis using Whole Mount Sections after Radical Prostatectomy

PURPOSE

To determine whether the fusion of multiparametric magnetic resonance imaging (MRI) with transrectal real-time elastography (RTE) improves the visualization of PCa lesions compared to MRI alone.

MATERIALS AND METHODS

In a prospective setting, 45 patients with biopsy-proven PCa received prostate MRI prior to radical prostatectomy (RP). T2 and diffusion-weighted imaging (T2WI/DW-MRI) and, if applicable, dynamic contrast-enhanced sequences (T2WI/DW/DCE-MRI) were used to perform MRI/RTE fusion. The probability of PCa on MRI was graded according to the PI-RADS score for 12 different prostate sectors per patient. MRI images were fused with RTE to stratify suspicious from non-suspicious sectors. Imaging results were compared to whole mount sections using nonparametrical receiver operating characteristic curves and the area under these curves (AUC).

RESULTS

41 of 45 patients were eligible for final analyses. Histopathology confirmed PCa in 261 (53%) of 492 prostate sectors. MRI alone provided an AUC of 0.62 (T2WI/DW-MRI) and 0.65 (T2WI/DW/DCE-MRI) to predict PCa and was meaningfully enhanced to 0.75 (T2WI/DW-MRI) and 0.74 (T2WI/DW/DCE-MRI) using MRI/RTE fusion. Sole MRI showed a sensitivity and specificity of 57.9% and 61% with the best results for ventral prostate sectors whereas RTE was superior in dorsal and apical sectors. MRI/RTE fusion improved sensitivity and specificity to 65.9% and 75.3%, respectively. Additional use of DCE sequences showed a sensitivity and specificity of 65% and 55.7% for MRI and 72.1% and 66% for MRI/RTE fusion.

CONCLUSION

MRI/RTE fusion provides improved PCa visualization by combining the strength of both imaging techniques in regard to prostate zonal anatomy and thereby might improve future biopsy-guided PCa detection.

[Value of real-time elastography to guide the systematic prostate biopsy in men with normal digital rectal exam]

The aim of this study was to evaluate whether real-time elastography-guided biopsy in comparison to grey-scale ultrasound improves prostate cancer detection in patients with an unremarkable digital rectal exam.A total of 231 patients suspicious for prostate cancer were prospectively randomised to transrectal real-time elastography- (126) or grey-scale ultrasound (105)-guided biopsy. The peripheral zone was divided into 6 sectors from base, mid-gland to apex. Lesions with reduced elasticity during real-time elastography and hypoechoic areas during grey-scale ultrasound were defined as suspicious for prostate cancer. Prostate biopsy was guided by real-time elastography (RTE) or grey-scale ultrasound (GSU) using a systematic 10-core approach. Suspicious lesions on RTE or GSU in the corresponding randomised group were targeted within each sector. Accuracy of cancer prediction and histopathological cancer detection rates were evaluated and compared between the 2 imaging modalitiesBaseline characteristics of patients undergoing real-time elastography and grey-scale ultrasound, including age, prostate-specific antigen and prostate volume were not significantly different statistically (p>0.05). Overall, prostate cancer was detected in 76 of 231 cases (32.9%). The cancer detection rate was significantly higher (p=0.007) in patients who underwent a biopsy using real-time elastography (40.5%) compared to the grey-scale-guided group of men (23.8%). Sensitivity and specificity to detect prostate cancer in 1 386 prostate sectors was 53.5% and 70.5% for real-time elastography vs. 11.7% and 93.7% for grey-scale ultrasound, respectively.Compared to conventional grey-scale ultrasound, accuracy to detect prostate cancer using a systematic 10-core biopsy approach was significantly improved under the guidance of real-time elastography.

[Cystectomy in elderly patients: analysis of complications using the Clavien-Dindo classification]

Radical cystectomy (RC) represents the gold standard in the treatment of muscle invasive urothelial cancer of the bladder. Due to improvements in operation techniques and perioperative care it has become a good and safe procedure even in elderly patients. In recent years the Clavien-Dindo classification has been frequently used for complication assessment in urological research. The Charlson comorbidity index without age correction can be used in treatment planning for RC to identify patients at risk.