The role of multiparametric mri in the diagnosis of local recurrence after radical prostatectomy and before salvage radiotherapy

PURPOSE

Assess multiparametric-MRI (mp-MRI) diagnostic accuracy in the detection of local recurrence of Prostate Cancer (PCa) after Radical Prostatectomy (PR) and before Radiation Therapy (RT).

MATERIALS AND METHODS

A total of 188 patients underwent 1.5-T mp-MRI after RP before RT. Patients were divided into two groups: with biochemical recurrence (group A) and without but with high risk of local recurrence (group B). Continuous variables were compared between two groups using T-Student; categoric variables were analyzed using Pearson chi-square. ROC analysis was performed considering PSA before RT, ISUP, pT and pN as grouping variables.

RESULTS

PCa recurrence (reduction of PSA levels after RT) was 89.8% in the group A and 80.3% in the group B. Comparing patients with and without PCa recurrence, there was a significant difference in PSA values before RT for group A and for PSA values before RT and after RT for group B. In group A, there was a significant correlation between PSA before RT and diameter of recurrence and between PSA before RT and time spent before recurrence. The mp-MRI diagnostic accuracy in detecting PCa local recurrence after RP is of 62.2% in group A and 38% in group B. DWI is the most specific MRI-sequence and DCE the most sensitive. For PSA = 0.5 ng/ml, the AUC decreases while sensitivity and accuracy increase for each MRI-sequence. For PSA = 0.9 ng/ml, DCE-AUC increases significantly.

CONCLUSION

mp-MRI should always be performed before RT when a recurrence is suspected. New scenarios can be opened considering the role of DWI for PSA ≤ 0.5 ng/ml.

Ultrasound Guided versus Direct Vein Puncture in Central Venous Port Placement

Introduction

This study will report our experience on positioning of totally implanted venous catheter system (port-a-cath) as compared to ultrasound guidance versus blind technique.

Materials and Methods

From July 1996 to November 1999 in the vascular suite of the Europen Institute of Oncology, 427 port-a-cath were implanted in patients with neoplastic disease. All devices were implanted through the subclavian vein. 198 with ultrasound guided puncture and 229 following anatomical landmarks. All patients underwent a close and specific clinical and instrumental follow-up to evaluate possible complications.

Results

Use of Ultrasound (US) in subclavian vein catheterization has reduced the number of puncture attempts, with a better patient complicance, allowing a faster procedure and reducing peri-procedural complications. Ultrasound technique has shown reduction in early complications. In fact in our experience we had no pneumothorax events by using ultrasound guidance, versus 11 events with blind technique. US has shown no reduction in late complications: 3 thrombosis versus 6 thrombosis with US guidance, and 3 fractured and embolized catheter versus 2 cases. Fibrin-cuff percentage was the same in the two groups with only 1 case, as the dislocation of the catheter tip in the jugular vein with 2 cases in both groups. Moreover US let us to avoid the arterial puncture and to perform a more peripheral puncture of the subclavian vein, reducing the risk of “pinch-off” phenomenon and of haematoma, with no cases reported under US guidance versus 1 case respectively in direct vein puncture.

Conclusions

US guided puncture of subclavian vein for the implantation of venous catheter system is faster by reducing procedure time, it is easier for the operator and safer for the patient than blind technique by exposing anatomical structures. Morevover US guidance reduces early complications and limits costs.

Radiofrequency versus microwave ablation for treatment of the lung tumours: LUMIRA (lung microwave radiofrequency) randomized trial

The LUMIRA trial evaluated the effectiveness of radiofrequency (RFA) and microwave ablation (MWA) in lung tumours ablation and defining more precisely their fields of application. It is a controlled prospective multi-centre random trial with 1:1 randomization. Fifty-two patients in stage IV disease (15 females and 37 males, mean age 69 y.o., range 40-87) were included. We randomized the patients in two different subgroups: MWA group and RFA group. For each group, we evaluated the technical and clinical success, the overall survival and complication rate. Inter-group difference was compared using Chi-square test or Fisher's exact test for categorical variables and one-way ANOVA test for continuous variables. For RFA group, there was a significant reduction in tumour size only between 6 and 12 months (p value = 0.0014). For MWA group, there was a significant reduction in tumour size between 6 and 12 months (p value = 0.0003) and between pre-therapy and 12 months (p value = 0.0215). There were not significant differences between the two groups in terms of survival time (p value = 0.883), while the pain level in MWA group was significantly less than in RFA group (1.79 < 3.25, p value = 0.0043). In conclusion, our trial confirms RFA and MWA are both excellent choices in terms of efficacy and safety in lung tumour treatments. However, when compared to RFA therapy, MWA produced a less intraprocedural pain and a significant reduction in tumour mass.

Temperature monitoring during microwave ablation in ex vivo porcine livers

OBJECTIVE

The aim of the present study was to assess the temperature map and its reproducibility while applying two different MWA systems (915 MHz vs 2.45 GHz) in ex vivo porcine livers.

MATERIALS AND METHODS

Fifteen fresh pig livers were treated using the two antennae at three different settings: treatment time of 10 min and power of 45 W for both systems; 4 min and 100 W for the 2.45 GHz system. Trends of temperature were recorded during all procedures by means of fiber optic-based probes located at five fixed distances from the antenna, ranging between 10 mm and 30 mm. Each trial was repeated twice to assess the reproducibility of temperature distribution.

RESULTS

Temperature as function of distance from the antenna can be modeled by a decreasing exponential trend. At the same settings, temperature obtained with the 2.45 GHz system was higher than that obtained with the 915 MHz thus resulting into a wider area of ablation (diameter 17 mm vs 15 mm). Both systems showed good reproducibility in terms of temperature distribution (root mean squared difference for both systems ranged between 2.8 °C and 3.4 °C).

CONCLUSIONS

When both MWA systems are applied, a decreasing exponential model can predict the temperature map. The 2.45 GHz antenna causes higher temperatures as compared to the 915 MHz thus, resulting into larger areas of ablation. Both systems showed good reproducibility although better results were achieved with the 2.45 GHz antenna.

Dynamic contrast-enhanced MR evaluation of prostate cancer before and after endorectal high-intensity focused ultrasound

PURPOSE

The authors sought to determine the diagnostic performance of dynamic contrast-enhanced magnetic resonance (DCE-MR) imaging in the evaluation of prostate cancer before and after transrectal high-intensity focused ultrasound (HIFU) treatment.

MATERIALS AND METHODS

We analysed 25 patients with prostate cancer. The prostate-specific antigen (PSA) value was evaluated 1, 4 and 6 months after treatment. DCE-MR imaging was performed the day prior to and 1, 4 and 6 months after HIFU treatment. Transrectal prostate biopsies were obtained at the time of diagnosis and 6 months after treatment.

RESULTS

Before treatment, intraglandular lesions were considered to be potential sites of neoplasm and subsequently confirmed as sites of prostate adenocarcinoma in all 25 patients based on prostatespecific antigen (PSA) values and histological examinations (rho=1; p<0.001). Using histology as the gold standard, DCE-MR imaging displayed 100% sensitivity, 100% specificity, 100% positive predictive value and 100% negative predictive value before treatment. After HIFU treatment, DCE-MR imaging showed 100% sensitivity and 96% specificity.

CONCLUSIONS

DCE-MR imaging can be used to visualise prostate adenocarcinoma. Several morphological and postgadolinium modifications in the follow-up DCE-MR images after HIFU treatment were also observed.

MR imaging of rectal cancer before and after chemoradiation therapy

PURPOSE

This study was done to determine the diagnostic accuracy of magnetic resonance (MR) imaging in patients with rectal carcinoma by comparing post-chemoradiation MR imaging with pathological specimens.

MATERIALS AND METHODS

We enrolled 39 patients with locally advanced rectal cancer. All patients received chemoradiation therapy before surgery and neoadjuvant chemoradiation therapy followed by MR imaging. MR images were analysed by a team of two expert radiologists unaware of the clinical and histopathological findings.

RESULTS

Following neoadjuvant chemoradiation therapy, the analysis of MR images showed 23 (59%) patients with a rectal disease staged ≤T2 and 16 (41%) with a disease staged >T2. Post-treatment histological staging (TNM) revealed 13 patients with a disease >T2 and 26 patients with a disease ≤T2. Cohen's kappa to measure concordance between post-chemoradiation MR staging and histological response showed 83.6% concordance for disease confined to the serosa (≤T3): concordance was 97.22% for disease ≤N1 and 33.33% for disease >N1.

CONCLUSIONS

MR imaging is critical for discovering T3 disease; moreover, morphological MR imaging does not always provide the opportunity to discern small residual cancer cells hidden in fibrotic tissue that could cause involvement of circumferential resection margin (CRM) on histology.

Posterior pelvic floor disorders: a prospective comparison using introital ultrasound and colpocystodefecography

OBJECTIVE

To compare introital ultrasound with colpocystodefecography (CCD) in quantifying the anorectal angle and in the diagnosis of posterior pelvic floor disorders.

METHODS

Forty-three consecutive women with functional impairment of the posterior pelvic floor were enrolled after a clinical evaluation. Using both CCD and introital ultrasound examination, the anorectal angle was measured during squeezing to evaluate the strength of voluntary muscle contraction and during straining to assess pelvic floor relaxation. Rectocele depth and the presence of intussusception were assessed. The performance of CCD and that of introital ultrasound were compared.

RESULTS

Good concordance was obtained between introital ultrasound and CCD. The intraclass correlation coefficient was 0.82 (95% CI, 0.69-0.89) for measurement of the anorectal angle during squeezing and 0.67 (95% CI, 0.47-0.81) during straining. Rectoceles > 4 cm on CCD were detected by introital ultrasound in 100% of cases, and there was 91% agreement for rectal intussusception. Cohen's kappa index was moderate for rectocele assessment (0.41, P < 0.01) and excellent for intussusception (0.91, P < 0.001). It was also noted that introital ultrasound could be used to detect pelvic floor dyssynergia.

CONCLUSIONS

Introital ultrasound is a simple, accurate, non-invasive method with which to assess anorectal dynamics.

Hepatic intra-arterial chemotherapy using a percutaneous catheter in pretreated patients with metastatic colorectal carcinoma

BACKGROUND

Hepatic intra-arterial chemotherapy (HIAC) leads to a higher response rate than systemic administration in untreated patients with liver metastases from colorectal cancer (CRC). The aim of this study was to evaluate the activity and safety of giving HIAC through a percutaneous catheter in pre-treated patients.

PATIENTS AND METHODS

Forty-five CRC patients with liver-only or liver-dominant metastases, resistant or refractory to previous systemic therapy, were treated using a temporary trans-subclavian catheter. A 3-day chemotherapy regimen of daily 5-fluorouracil (5-FU) 1000 mg/m2/day + heparin 5000 IU/day given as a 24-hour continuous infusion, and twice daily bolus injections of cisplatin (CDDP) 10 mg/m2 and mitomycin C (MMC) 2 mg/m2, was administered every six weeks.

RESULTS

One hundred and seventeen courses were administered to 45 patients (a median of three per patient: range 1-5). Of the 44 patients evaluable for response, 16 (35%) had a partial response, 15 (33%) stable disease and 12 (26%) progressive disease. Eleven of the 16 responding patients had been refractory to a previous 5-FU-based systemic therapy. The most relevant grade 3-4 toxicities included neutropenia (22%) and thrombocytopenia (15%). Gastro-duodenal ulcers occurred in nine patients. Catheter displacement was recorded during 22 out of 117 (18%) courses.

CONCLUSION

HIAC with 5-FU, CDDP and MMC given through a temporary percutaneous catheter is safe and active in pretreated patients with metastatic CRC. Iatrogenic gastroduodenal ulcers are a serious but manageable complication.

Endorectal magnetic resonance imaging in the preoperative staging of rectal tumors

A proper preoperative staging of rectal tumors is important for correct treatment planning. We included in our study 23 patients with rectal carcinoma in order to evaluate the diagnostic accuracy of endorectal MRI. This technique enabled us to show neoplasms as a hyperintense lesion as compared to the muscolaris. To better delineate the renal dimensions of the neoplasms and reduce chemical shift artifact we performed T2 weighted TSE sequences with and without fat suppression. The diagnostic accuracy in the evaluation of T and N factors as compared to surgery was respectively 78.2% and 78.9%. The major problem has been a slight tendency to overstage parietal infiltration and lymphnodal involvement. Endorectal MRI allows us to obtain an excellent anatomic detail of the three rectal wall layers and a very high spatial resolution which might make this technique the examination of choice in the evaluation of rectal carcinoma.

[Biliary-enteric anastomosis: role of cholangiography with magnetic resonance]

Our study was aimed at investigating the role of MR-cholangiography (MRC) in the examination of patients treated with biliary-enteric anastomosis. MRC was performed in 15 patients (8 men and 7 women, mean age: 64.7 years) operated on for biliary-enteric anastomoses (13 hepaticojejunostomies and 2 choledochoduodenostomies) whose symptoms were as follows: persistent jaundice in 4 patients; cholangitis and abnormal liver function tests in 2 patients; associated transient jaundice, epigastric pain, abnormal liver function tests in 2 patients. The remaining 7 patients were asymptomatic and examined during their follow-up. MRC was performed with a non-breath-hold, fat-suppressed 3D turbo spin echo sequence (TR = 3000 msec, TE = 700 msec, ETL = 128) with an acquisition time ranging 4 min 24 sec to 5 min 48 sec. Six patients were subsequently submitted to Percutaneous Transhepatic Cholangiography (PTC) to confirm the diagnosis and to perform a therapeutical procedure. Two patients, submitted to choledochoduodenostomy were examined with ERCP. The remaining seven patients, examined during their surgical follow-up and who presented no major symptoms or dilation of the bile ducts, were not submitted to any invasive procedure. Image quality was graded as good to fair in 12/15 cases (80%) and poor in 3/15 cases (20%). The degree of bile ducts dilation was correctly assessed with complete inter observer agreement in 8/8 patients. MRCP correctly showed: bile ducts irregularities in 2 of 4 patients with cholangitis (k = 0.59), anastomosis stenosis in 8 of 8 patients (k = 0.86), and 5-15 mm stones in 5 of 5 patients (k = 0.95). In conclusion, MRCP is a safe, noninvasive technique in the study of biliary-enteric anastomoses with high accuracy in assessing the cause of jaundice. MRCP images can be used as a guide for subsequent interventional procedures. Its main disadvantages are the lack of functional information and the high cost which limits its its use to the screening of symptomatic patients.

[Magnetic resonance angiography of the portal vein in liver transplant recipients]

This work was aimed at investigating the diagnostic accuracy of Magnetic Resonance Angiography (MRA) in the study of the portal vein in liver transplant recipients. Ten patients (7 men and 3 women; mean age: 45 years) were examined 7-180 days after transplantation. The indications to liver transplant follow: post-infective active chronic hepatitis (4 patients), post-alcoholic chronic hepatitis (2 patients), HCC (2 patients), sclerosing cholangitis (1 patient) and primary biliary cirrhosis (1 patient). MRA images were acquired with the 2D TOF technique (TR 50 ms, TE 6.9 ms; FA 30 degrees, 40 slices; 6-mm thickness with 1-mm overlapping; 2 averages; 7.06 TA; matrix: 192 x 256). Axial scans were reconstructed with the MIP technique. Phase contrast sequences with retrospective cardiac triggering were also acquired for flow quantitation (TR/TE/FA: 26/9.3/20 degrees; FOV 150; matrix: 96 x 128; 4 averages, VENC = 20 cm/s). MRA yielded good quality images of the anatomy of the main portal vein and of the bifurcation in all cases, while a signal loss was observed in the peripheral branches. In all cases, the anastomosis could be studied at the portal vein. On MIP reconstructed images, the anastomosis appeared as a relative stenosis (4), while on 2D images it appeared as a small hypodense area on the vessel margin, because of the slight paramagnetic effect of the vascular suture. No thrombi were depicted in any patient and flow was hepatopetal in all cases. In conclusion, MRA is a useful tool for portal system studies in liver transplant recipients, because it permits the panoramic depiction of the portal system and the quantitation of flow (10).

[Animal experimentation in radiology. Objectives, organizational and ethical problems]

The contribution of biomedical sciences to the scientific breakthroughs in the last years has benefitted also by experiments on animals. As for diagnostic imaging, the use of new contrast media for angiography, CT and MRI makes it necessary, according to the law, to perform preliminary animal studies to test efficacy, pharmacokinetics and pharmacodynamics of the contrast agents. Experimental animal studies of clinically well-established contrast agents are also justified by the need to implement new imaging modalities. The close relationship between medical research and animal experimentation has awakened public opinion, as well as the researchers themselves, to the ethical and legal problems related to animal testing. This paper reports on the regulations which are currently in use in this field.