Combined T2-weighted and diffusion-weighted MRI for diagnosis of urinary bladder invasion in patients with prostate carcinoma

Fusion of high B-value diffusion-weighted and T2-weighted MR images increases sensitivity for identification of extraprostatic disease in prostate cancer

PURPOSE

To evaluate whether fusion of high b-value diffusion-weighted imaging (DWI) and T2-weighted imaging (T2WI) increases radiologists' ability to detect pathologic features responsible for upstaging in prostate cancer patients prior to radical prostatectomy (RP).

BASIC PROCEDURES

This was a retrospective study including 103 patients who underwent RP and a prostate MRI performed at 3T. High b-value DWI and T2WI were fused and interpreted by three radiologists with different degrees of experience. Prior to and after fusion, readers answered questionnaires about cancer presence, extraprostatic extension (EPE), seminal vesicle (SV) invasion, lymph node (LN) involvement, and reader confidence. Pathology reports served as the reference standard.

MAIN FINDINGS

High b-value DWI-T2WI fusion increased sensitivity for detection of EPE from 65.6% to 77.4% (p < 0.05), SV invasion from 40.5% to 48.8% (p < 0.05), and LN metastasis by 23.8% to 44.4% (p < 0.05). Readers' confidence significantly improved with the use of fusion imaging. Across all readers, confidence of cancer detection increased by 12.5% (p < 0.05), EPE by 14.7% (p < 0.05), SV invasion by 8.1% (p < 0.05), and LN metastasis by 2.5% (p < 0.05) using Wilcoxon signed rank test.

PRINCIPAL CONCLUSIONS

Fusion overlay of high b-value DWI and T2WI increases sensitivity for detection of extraprostatic disease resulting in upstaging at the time of RP.

Advanced colonic cancer with clinically suspected bladder invasion: Outcomes and prognosis from a multicentric study of 117 patients from the FRENCH research group

BACKGROUND

Bladder invasion by colon cancer is rare; however, its management is still controversial. Our objective was to report outcomes and identify risk factors for local recurrence in colon cancer with clinically suspected bladder invasion.

METHODS

We conducted a retrospective study in 23 centers in France. All patients who underwent colon surgery with bladder resection (2010-2017) were included. Metastatic and recurrent colon cancers were excluded.

RESULTS

One hundred and seventeen patients (men = 73) were included. Partial cystectomy occurred in 108 patients (92.3%), with a total cystectomy occurring in 9 patients (7.7%). Neoadjuvant treatment was given to 31 patients (26.5%). Major morbidity was 20.5%. R0 resection rates were 87.2%. Histologically confirmed bladder invasion was present in 47%. Thirty-four patients were pN+, while 60 patients (51.3%) received adjuvant chemotherapy. Mean follow-up was 33.8 months. Three-year overall survival and disease-free survival were 82.9% and 59.5%. Rates of local recurrence and distant recurrence were 14.5% and 18.8%, respectively; the local recurrences (11/17; 65%) were in the bladder, while 4 of these patients had a bladder recurrence despite not having histologically confirmed bladder invasion at the index surgery. The rate of bladder recurrence after histologic bladder invasion was 13% (7/55), while the rate of bladder recurrence without primary bladder invasion was 7% (4/62) (P = .343). Neoadjuvant therapy, type of cystectomy, and adjuvant therapy did not influence local recurrence (P > .445 each). R1 bladder resections, when compared with a R0 bladder resections, were associated with an increased rate of local recurrence (63% vs 10%; P < .0001).

CONCLUSION

Clinically suspected bladder invasion increases local recurrence even in the absence of histologically confirmed bladder invasion. Only complete resections with R0 margins decrease local recurrence. Careful, detailed postoperative surveillance is required, even without pathologic bladder invasion.

Current and Future Approaches for Effective Cancer Imaging and Treatment

Cancer poses a major health problem, not only due to cancer-related deaths but also because of treatment toxicities. This review discusses early diagnosis and strategies to overcome treatment difficulties, to facilitate recovery, and prevent deaths. Generally, noninvasive techniques such as computed tomography (CT), magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT) and positron emission computed tomography (PET), and their hybrid systems, including SPECT/CT, PET/CT, and PET/MRI, are used in diagnosis of cancer. Cancer treatment in clinics still comprises conventional methods such as chemotherapy, radiotherapy, and surgery. However, these techniques and methods are often inadequate. Therefore, new approaches, including the formulation of actively and/or passively targeted nanosized drug delivery systems and combined treatment protocols, are being investigated. In this article, conventional cancer imaging and treatment are reviewed. In addition, the formulation of nanosized systems and their use in cancer treatment are discussed and combined diagnostic and therapeutic (theranostic) approach are proposed as additional cancer therapies.

Diffusion-weighted MRI and its role in prostate cancer

In the last 5 years, the multiparametric approach has been investigated as the method for the MRI of prostate cancer. In multiparametric MRI of the prostate, at least two functional MRI techniques, such as diffusion-weighted MRI (DW-MRI) and dynamic contrast-enhanced MRI, are combined with conventional MRI, such as T2 -weighted imaging. DW-MRI has the ability to qualitatively and quantitatively represent the diffusion of water molecules by the apparent diffusion coefficient, which indirectly reflects tissue cellularity. DW-MRI is characterized by a short acquisition time without the administration of contrast medium. Thus, DW-MRI has the potential to become established as a noninvasive diagnostic method for tumor detection and localization, tumor aggressiveness, local staging and local recurrence after various therapies. Accordingly, radiologists should recognize the principles of DW-MRI, the methods of image acquisition and the pitfalls of image interpretation.

Outcome of urinary bladder recurrence after partial cystectomy for en bloc urinary bladder adherent colorectal cancer resection

PURPOSE

Around 10 % of colorectal cancers are locally advanced at diagnosis. There are higher incidences for sigmoid and rectal cancer adhered to urinary bladder (UB) rather than other segments of colon cancer. Surgeons often performed partial cystectomy as possible for preservation of patient's life quality. This study investigates prognostic factors in patients who underwent bladder preservation en bloc resection for UB adherent colorectal cancer.

METHODS

From 2000 to 2011, 123 patients with clinically UB involvement colorectal cancer underwent primary colorectal cancer with urinary bladder resection. Seventeen patients were excluded because of the concurrent distant metastasis at diagnosis and another 22 patients were excluded because of total cystectomy with uretero-ileal urinary diversion. Finally, 84 patients with clinical stage IIIC (T4bN0M0, according to AJCC 7th edition) that underwent en bloc colorectal cancer resection with partial cystectomy were enrolled into this study for further analysis.

RESULTS

Preoperative colovesical fistula and positive CT result were significantly more in the urinary bladder invasion group (p = 0.043 and 0.010, respectively). Pathological UB invasion is an independent predictor of intravesical recurrence (p = 0.04; HR, 10.71; 95 % CI = 1.12∼102.94) and distant metastasis (p = 0.016; HR, 4.85; 95 % CI = 1.34 ∼ 17.53) in multivariate analysis.

CONCLUSIONS

For bladder preservation en bloc resection of urinary bladder adherent colorectal cancer, the pathological urinary bladder invasion is significantly associated with more urinary bladder recurrence and distant metastasis. This result helps surgeons make decisions at surgical planning and establish follow-up protocol.

Diffusion-weighted MRI in the detection of prostate cancer: meta-analysis

OBJECTIVE

The objective of our study was to estimate and compare the performance of diffusion-weighted imaging (DWI) with other MRI techniques including T2-weighted MRI for the detection of prostate cancer.

MATERIALS AND METHODS

Searches of the PubMed and Scopus electronic databases for the terms "prostate," "cancer," "diffusion-weighted imaging," and "magnetic resonance imaging" using an end date of December 2010 were completed. All included studies had histopathologic correlation; 2×2 contingency data were constructed for each study. A Bayesian receiver operating characteristic (ROC) model was used across studies to determine sensitivity, specificity, and area under the full or partial ROC curve.

RESULTS

Nineteen articles consisting of a total of 5892 lesions were analyzed. Based on a 95% credible interval, DWI alone yielded a significantly better area under the ROC curve, sensitivity, and specificity (0.85, 0.69, 0.89, respectively) than T2-weighted imaging alone (0.75, 0.60, 0.76). Combined DWI and T2-weighted imaging (0.73, 0.70, 0.83) showed a similar area under the ROC curve but significantly better sensitivity and specificity than T2-weighted imaging alone. DWI and combined DWI and T2-weighted imaging yielded similar overall sensitivity, but DWI alone showed better overall specificity than combined DWI and T2-weighted imaging. At specificities of greater than 80%, combined DWI and T2-weighted imaging yielded a partial area under the ROC curve (0.138) similar to that of DWI alone (0.129) and was significantly better than the partial area under the ROC curve of T2-weighted imaging alone (0.070). DWI alone and combined DWI and T2-weighted imaging appear to be superior to dynamic contrast-enhanced imaging alone (area under the ROC curve, 0.79; sensitivity, 0.58; specificity, 0.82).

CONCLUSION

DWI appears to improve diagnostic performance and can be a useful adjunct to conventional anatomic imaging for identifying tumor foci in prostate cancer.

Correlation between surrogates of bladder dosimetry and dose-volume histograms of the bladder wall defined on MRI in prostate cancer radiotherapy

The correlation between bladder dose-wall-histogram (DWH) and dose-volume-histogram (DVH), dose-surface-histogram (DSH), and DVH-5/10 was investigated in a group of 28 patients; bladder walls were drawn on T2-MRI. DVH showed the poorest correlation with DWH; DSH or DVH-5/10 should be preferred in planning; absolute DVH may be used for radical patients, although less robust.

Targeted biopsy based on ADC map in the detection and localization of prostate cancer: a feasibility study

Purpose

To investigate the feasibility of targeted biopsy based on an apparent diffusion coefficient (ADC) map in the detection and localization of prostate cancer.

Materials and Methods

This study included 288 consecutive patients with high or increasing serum prostate-specific antigen (PSA) levels who underwent prostatic magnetic resonance imaging (MRI) examination with an ADC map. Four core-targeted biopsies of low ADC lesions were performed under transrectal-ultrasound guidance with reference to ADC map. The positive predictive values (PPVs) of low ADC lesions were calculated and compared for the peripheral zone (PZ), transition zone (TZ), and anterior portion, respectively. Comparisons of ADC values and sizes between malignant and nonmalignant lesions were also performed.

Results

A total of 313 low ADC lesions were detected in 195 patients and sampled by targeted biopsies. The PPVs were 55.3% (95% confidence interval [CI]: 50–61) in total, 61.0% (95% CI: 53–69) for PZ, 50.6% (95% CI: 43–58) for TZ, and 90.9% (95% CI: 81–100) for the anterior portion. The most common nonmalignant pathology of low ADC lesions was hyperplasia, followed by chronic prostatitis. There were significant differences in ADC values and sizes between malignant and nonmalignant low ADC lesions.

Conclusion

Targeted biopsies could be capable of detecting cancers well wherever they may be in the prostate, although the PPVs varied depending on the location of low ADC lesions.

The clinical value of diffusion-weighted imaging in combination with T2-weighted imaging in diagnosing prostate carcinoma: a systematic review and meta-analysis

OBJECTIVE

We aimed to explore the role of diffusion-weighted imaging (DWI) in combination with T2-weighted imaging (T2WI) in detecting prostate carcinoma through a systematic review and meta-analysis.

MATERIALS AND METHODS

The MEDLINE, EMBASE, Cancerlit, and Cochrane Library databases were searched for studies published from January 2001 to July 2011 evaluating the diagnostic performance of T2WI combined with DWI in detecting prostate carcinoma. We determined sensitivities and specificities across studies, calculated positive and negative likelihood ratios, and constructed summary receiver operating characteristic curves. We also compared the performance of T2WI combined with DWI with T2WI alone by analyzing studies that had also used these diagnostic methods on the same patients.

RESULTS

Across 10 studies (627 patients), the pooled sensitivity of T2WI combined with DWI was 0.76 (95% CI, 0.65-0.84), and the pooled specificity was 0.82 (95% CI, 0.77-0.87). Overall, the positive likelihood ratio was 4.31 (95% CI, 3.12-5.92), and the negative likelihood ratio was 0.29 (95% CI, 0.20-0.43). In seven studies in which T2WI combined with DWI and T2WI alone were performed, the sensitivity and specificity of T2WI combined with DWI were 0.72 (95% CI, 0.67-0.82) and 0.81 (95% CI, 0.76-0.86), respectively, and the sensitivity and specificity of T2WI alone were 0.62 (95% CI, 0.55-0.68) and 0.77 (95% CI, 0.71-0.82), respectively.

CONCLUSION

T2WI combined with DWI may be a valuable tool for detecting prostate cancer in the overall evaluation of prostate cancer, compared with T2WI alone. High-quality prospective studies of T2WI combined with DWI to detect prostate carcinoma still need to be conducted.

Clinical utility of diffusion-weighted magnetic resonance imaging in prostate cancer

What's known on the subject? and What does the study add? This article reviews what is currently known about diffusion weighted MRI (DW-MRI) in prostate cancer. This mini-review concisely summarises, for clinical managing patients with prostate cancer, the clinical utility of diffusion weighted MRI.

OBJECTIVE

• To review the clinical utility of diffusion-weighted magnetic resonance imaging (DW-MRI) in patients with prostate cancer.

MATERIAL AND METHODS

• The current literature on prostate cancer and DW-MRI was reviewed.

RESULTS

• DW-MRI can be readily acquired on a modern scanner with a short image acquisition time and no need for i.v. contrast medium. • The image contrast is based on the diffusion of water molecules and thus reflects tissue cellularity. • There is increasing evidence that DW- MRI improves the sensitivity and specificity of prostate cancer detection as well as the identification of tumour aggressiveness. • DW-MRI is also showing substantial promise as a response biomarker for both local and metastatic disease

CONCLUSIONS

• DW-MRI is proving to be a useful adjunct to conventional T2-weighted MRI sequences. • The eventual role of DW-MRI in combination with other MRI techniques for multiparametric assessment of prostate cancer needs to be defined further.

Diffusion weighted imaging in prostate cancer

Diffusion-weighted imaging has generated substantial interest in the hope that it can be developed into a robust technique to improve the accuracy of MRI for the evaluation of prostate cancer. This technique has the advantages of short acquisition times, no need for intravenous administration of contrast medium, and the ability to study diffusion of water molecules that indirectly reflects tissue cellularity. In this article, we review the existing literature on the utility of DWI in tumour detection, localisation, treatment response, limitations of the technique, how it compares with other imaging techniques, technical considerations and future directions.