Multiparametric MRI fusion-guided biopsy for the diagnosis of prostate cancer

Radiogenomic analysis of ultrasound phenotypic features coupled to proteomes predicts metastatic risk in primary prostate cancer

BACKGROUND

Primary prostate cancer with metastasis has a poor prognosis, so assessing its risk of metastasis is essential.

METHODS

This study combined comprehensive ultrasound features with tissue proteomic analysis to obtain biomarkers and practical diagnostic image features that signify prostate cancer metastasis.

RESULTS

In this study, 17 ultrasound image features of benign prostatic hyperplasia (BPH), primary prostate cancer without metastasis (PPCWOM), and primary prostate cancer with metastasis (PPCWM) were comprehensively analyzed and combined with the corresponding tissue proteome data to perform weighted gene co-expression network analysis (WGCNA), which resulted in two modules highly correlated with the ultrasound phenotype. We screened proteins with temporal expression trends based on the progression of the disease from BPH to PPCWOM and ultimately to PPCWM from two modules and obtained a protein that can promote prostate cancer metastasis. Subsequently, four ultrasound image features significantly associated with the metastatic biomarker HNRNPC (Heterogeneous nuclear ribonucleoprotein C) were identified by analyzing the correlation between the protein and ultrasound image features. The biomarker HNRNPC showed a significant difference in the five-year survival rate of prostate cancer patients (p < 0.0053). On the other hand, we validated the diagnostic efficiency of the four ultrasound image features in clinical data from 112 patients with PPCWOM and 150 patients with PPCWM, obtaining a combined diagnostic AUC of 0.904. In summary, using ultrasound imaging features for predicting whether prostate cancer is metastatic has many applications.

CONCLUSION

The above study reveals noninvasive ultrasound image biomarkers and their underlying biological significance, which provide a basis for early diagnosis, treatment, and prognosis of primary prostate cancer with metastasis.

How to avoid prostate biopsy in men with Prostate Image-Reporting and Data System 3 lesion? Development and external validation of new biopsy indication using prostate health index density

Background

To develop a customized prostate biopsy indication using prostate health index density (PHID) combined with multiparametric magnetic resonance imaging (mpMRI) and assess the reliability of the PHID cutoff value in external populations.

Methods

A total of 521 cognitive MRI/ultrasonography fusion prostate biopsies and biomarker tests for prostate-specific antigen (PSA), free PSA, and PHI were performed after mpMRI. The predictive value for clinically significant prostate cancer (csPCa; Gleason score≥7) of PSA derivatives was examined using the ROC curve. We developed a new biopsy indication utilizing a PHID cutoff based on the Prostate Image-Reporting and Data System (PI-RADS) score, which was externally validated.

Results

The combination of PHID and mpMRI (AUC = 0.884) demonstrated the highest predictive ability for csPCa, although PHID (AUC = 0.843) and PI-RADS (AUC = 0.806) individually also showed a high diagnostic value. When a PHID cutoff of 0.75 was used in men with PI-RADS 3 lesions, the negative predictive value of csPCa was 100%, and approximately half of the biopsies could be safely avoided.

Conclusion

Compared to PHID or PI-RADS scores alone, the combination of PHID and PI-RADS scores increased the accuracy of csPCa detection and the number of cases in which biopsy could be avoided. In men with PI-RADS 3 lesions, the optimal PHID cutoff ≥0.75 can prevent half of the unnecessary biopsies without missing csPCa. In men with PI-RADS 4-5 lesions, biopsies are warranted regardless of PHID values because csPCa could be accompanied by low PHID.

Multiplexed imaging in oncology

In oncology, technologies for clinical molecular imaging are used to diagnose patients, establish the efficacy of treatments and monitor the recurrence of disease. Multiplexed methods increase the number of disease-specific biomarkers that can be detected simultaneously, such as the overexpression of oncogenic proteins, aberrant metabolite uptake and anomalous blood perfusion. The quantitative localization of each biomarker could considerably increase the specificity and the accuracy of technologies for clinical molecular imaging to facilitate granular diagnoses, patient stratification and earlier assessments of the responses to administered therapeutics. In this Review, we discuss established techniques for multiplexed imaging and the most promising emerging multiplexing technologies applied to the imaging of isolated tissues and cells and to non-invasive whole-body imaging. We also highlight advances in radiology that have been made possible by multiplexed imaging.

Use of colour Doppler to eliminate rectal bleeding from trans-rectal ultrasound-guided biopsy of the prostate

Bleeding is one of the complications of trans-rectal ultrasound (TRUS)-guided biopsy of the prostate. Urethral bleeding could be prevented by avoiding the trajectory on the urethra. However, rectal bleeding is difficult to predict because the peri-prostatic, intra-prostatic and rectal vessels cannot be seen on an ordinary ultrasound scan. Use of colour Doppler to map out the vessels cognitively before injection of local anaesthesia prevents puncture of the vessels, which is a key cause of rectal bleeding.

Level of evidence:

Not applicable.

Quantitative ultrasound shear wave elastography (USWE)-measured tissue stiffness correlates with PIRADS scoring of MRI and Gleason score on whole-mount histopathology of prostate cancer: implications for ultrasound image-guided targeting approach

OBJECTIVE

To correlate quantitative tissue stiffness measurements obtained by transrectal ultrasound shear wave elastography (USWE) with PI-RADS scoring of multiparametric magnetic imaging resonance (mpMRI) using Gleason scores of radical prostatectomy as a reference standard.

PATIENTS AND METHODS

196 men with localised prostate cancer were prospectively recruited into the study and had quantitative prostate tissue stiffness measurements in kilopascals (kPa) using transrectal USWE prior to radical prostatectomy. PI-RADS scores of mpMRI were also obtained in all the men. Imaging and histopathology of radical prostatectomy specimen were oriented to each other using patient specific customised 3D moulds to guide histopathology grossing of radical prostatectomy specimens. All included patients had confirmed PCa on TRUS-guided biopsies, had both USWE and mpMRI imaging data, and underwent radical prostatectomy. Chi-square test with 95% confidence interval was used to assess the difference between Gleason score (GS) of radical prostatectomy and PI-RADS classification, as well as GS of radical prostatectomy and stiffness (in Kpa) using USWE. The correlation coefficient (r) was calculated in order to investigate relation between PI-RADS classification and tissue stiffness in kPa.

RESULTS

There was a statistically significant correlation between USWE-measured tissue stiffness and GS (χ2 (2, N = 196) = 23.577, p < 0.001). Also, there was a statistically significant correlation between Gleason score and PI-RADS score (χ2 (2, N = 196) = 12.838, p = 0.002). High PIRADS on MRI and high stiffness on USWE (> 100 kPa) detected more than 80% and 90% high risk prostate cancer disease. However, a weak correlation coefficient of 0.231 was observed between PI-RADS score and level of tissue stiffness measured in kPa.

CONCLUSION

Quantitative USWE and mpMRI using PI-RADS classification provide a good degree of prediction for Gleason score of clinically significant prostate cancer (csPCa). Stiffer lesions on ultrasound showed a weak correlation with PI-RADS scoring system. USWE could be used to target suspected prostate cancer.

Diagnostic Value of Transrectal Shear Wave Elastography for Prostate Cancer Detection in Peripheral Zone: Comparison with Magnetic Resonance Imaging

Objective: To assess the diagnostic value of transrectal shear wave elastography (SWE) for detecting prostate cancer (PCa) in peripheral zone and compare it with magnetic resonance imaging (MRI). Materials and Methods: Two hundred twenty-one patients suspected of PCa were enrolled, in which 172 patients of them underwent both SWE and MRI. Elastic value was measured in the area prepared for systematic biopsy and suspicious lesion detected on B-mode or SWE, histopathological result was compared for each biopsy. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were derived by obtaining optimal threshold from receiver operating characteristic (ROC) curve. The correlation between the stiffness of PCa and Gleason scores, prognostic grades, and percentage of cancer in biopsy were evaluated by Spearman rank correlation. Multivariate logistic regression analysis was performed to determine predictors for diagnosing PCa. The diagnostic capacity of MRI and SWE for detecting PCa and clinically significant PCa in the peripheral zone were assessed by comparing area under curve of ROC curve. Results: A value of 42 kPa was used as the cutoff for differentiating benign from malignant prostatic tissue; the sensitivity, specificity, PPV, NPV, and accuracy were 78.97%, 90.67%, 71.30%, 93.66% and 88.03%, respectively. Rank correlation analysis revealed that the stiffness of PCa had a correlation with Gleason score, prognostic grade, and percentage of cancer in biopsy. On multivariate analysis, the age, free prostate-specific antigen (PSA), PSA density, SWE, and MRI were independent predictors for diagnosing PCa. There was no statistical difference for diagnosing PCa between SWE and MRI (p = 0.259). However, for clinically significant PCa, the diagnostic capacity of SWE was a little higher than MRI (p = 0.013). Conclusions: SWE may provide additional information for PCa detection, which could increase the positive rate of PCa in targeted biopsy and reduce unnecessary biopsy. SWE is compatible with MRI for detecting PCa in the peripheral zone.

Prostate MRI and transperineal TRUS/MRI fusion biopsy for prostate cancer detection: clinical practice updates

This narrative review summarizes the current knowledge about multiparametric and biparametric magnetic resonance imaging of the prostate. This is provided from both a radiological and a urological point of view analyzing the technical aspects of fusion-targeted biopsy using the transperineal approach. We report practical considerations concerning pure cognitive and software-assisted settings, discuss the principal transperineal fusion software now available, and debate the pros and cons of choosing one approach over the other.

Real-time fusion-imaging in low back pain: a new navigation system for facet joint injections

AIMS AND OBJECTIVES

The aim of the current study is to present our experience in lumbar spine interventional procedures performed with a newly developed multimodal echo-navigator (EcoNav) and to evaluate short-term clinical outcomes of a series of patients affected by facet joint disease (FJD) treated with steroid and anaesthetic injection under fusion-imaging guidance, compared to a cohort of patients that received the same treatment under computed tomography (CT) guidance.

METHODS

Sixty-five consecutive patients (34 females; mean age 68.3 ± 12.8 years) with a clinical diagnosis of non-radicular low back pain lasting for more than 6-weeks and magnetic resonance (MR) or CT confirmed FJD were enrolled for image-guided FJI. Twenty-eight patients underwent FJI with fusion-guided technique, while CT-guided procedures were performed in the other cases. Clinical and procedural data were recorded and compared at a mean follow-up of 6.1 ± 2.0 months.

RESULTS

A significant improvement in clinical parameters was observed for both fusion-guided and CT-guided group. Comparing both groups, no statistically significant difference could be detected neither at baseline conditions nor during the follow-up period. No significant periprocedural complication occurred in both groups. A satisfaction rate of 92.3 and 81.1% was reported for fusion-guided and CT-guided group, respectively.

CONCLUSION

EcoNav fusion-imaging system represents a safe, feasible, effective and reproducible guidance option in FJD infiltration procedures, also avoiding use of ionising radiations.

Markers of clinical utility in the differential diagnosis and prognosis of prostate cancer

Molecular diagnostics is a rapidly evolving area of surgical pathology, that is gradually beginning to transform our diagnostical procedures for a variety of tumors. Next to molecular prognostication that has begun to complement our histological diagnosis in breast cancer, additional testing to detect targets and to predict therapy response has become common practice in breast and lung cancer. Prostate cancer is a bit slower in this respect, as it is still largely diagnosed and classified on morphological grounds. Our diagnostic immunohistochemical armamentarium of basal cell markers and positive markers of malignancy now allows to clarify the majority of lesions, if applied to the appropriate morphological context (and step sections). Prognostic immunohistochemistry remains a problematic and erratic yet tempting research field that provides information on tumor relevance of proteins, but little hard data to integrate into our diagnostic workflow. Main reasons are various issues of standardization that hamper the reproducibility of cut-off values to delineate risk categories. Molecular testing of DNA-methylation or transcript profiling may be much better standardized and this review discusses a couple of commercially available tests: The ConfirmDX test measures DNA-methylation to estimate the likelihood of cancer detection on a repeat biopsy and may help to reduce unnecessary biopsies. The tests Prolaris, OncotypeDX Prostate, and Decipher all are transcript tests that have shown to provide prognostic data independent of clinico-pathological parameters and that may aid in therapy planning. However, further validation and more comparative studies will be needed to clarify the many open questions concerning sampling bias and tumor heterogeneity.