PURPOSE:To create a magnetic resonance image (MRI)-based atlas of prostate bed recurrence for prostate cancer patients undergoing salvage radiation therapy (sRT) after radical prostatectomy, and to evaluate the consistency of contouring guidelines for the prostatic fossa-clinical target volume. METHODS AND MATERIALS:Patients with biochemical recurrence and MRI-detected prostate bed lesions before sRT were included. Each lesion was contoured on T2-weighted (T2w) MRI using dynamic contrast-enhanced sequences for guidance. Lesions were transferred to a reference T2-w data set through deformable co-registration to generate a 3-dimensional recurrence incidence map. The volume and location of the lesions were extracted. Seven prostatic fossa-clinical target volume contouring strategies were implemented on the reference T2w data set to assess coverage: the European Organisation for Research and Treatment of Cancer, the Faculty of Radiation Oncology Genito-Urinary Group, the Francophone Group of Urological Radiotherapy, the Radiation Therapy Oncology Group, the Princess Margaret Hospital (PMH), the European Society for Radiotherapy and Oncology-Advisory Committee for Radiation Oncology Practice (ESTRO), and PERYTON. Centroid- and volume-based coverage rates were calculated, and statistical comparisons were performed using Cochran's Q or Friedman tests. Correlations were analyzed with phi or Spearman's (rho, ρ) coefficients. RESULTS:One hundred and thirty-one patients with 140 recurrences were identified. Lesions were located at the vesicourethral anastomosis (53%), bladder neck (29%), and retrovesical region (18%). Median volume of the lesion was 0.48 cm3 (range, 0.03-40.5 cm3) (vesicourethral anastomosis), 0.29 cm3 (range, 0.09-3.72 cm3) (retrovesical region), and 0.49 cm3 (range, 0.02-3.51 cm3) (bladder neck). Centroid-based coverage ranged from 65% to 93%, with ESTRO, PMH, and PERYTON achieving the highest rates (92.1%-92.9%). Volume-based coverage ranged from 63.7% to 91.2%, again favoring ESTRO (91.2%) and PERYTON (90.3%). The European Organisation for Research and Treatment of Cancer strategy showed significantly lower coverage than all other contouring strategies in most comparisons, while strong positive correlations were observed among the remaining definitions, with the highest correlation between PMH and the Radiation Therapy Oncology Group (ρ = 0.94). CONCLUSIONS:According to the coverage criterion, our data support the use of ESTRO and PERYTON definitions. Here, we provide an MRI-based atlas of prostatic bed recurrence that can help optimize sRT contours.

Background: Multiparametric MRI is central to detecting clinically significant prostate cancer (csPCa), but diagnostic accuracy depends on reader experience. Artificial intelligence (AI) tools may support prostate MRI interpretation and reduce inter-reader variability. This study compared the detection rate of a trial, non-commercial version an AI-based software (PAROS) with that of an experienced radiologist. Methods: This retrospective single-center study included 150 patients who underwent prostate MRI followed by combined systematic and MRI-targeted transperineal biopsy. MRI examinations were interpreted by an experienced radiologist according to PI-RADS v2.1 and independently analyzed using a precommercial trial version of PAROS operating on biparametric MRI. Histopathology served as the reference standard. Detection rate was evaluated using sensitivity, specificity, and positive and negative likelihood ratios (PLR and NLR) at PI-RADS thresholds ≥3 and ≥4. Results: CsPCa was present in 63.3% of patients. At both PI-RADS thresholds, PAROS and the radiologist showed comparable sensitivity and specificity, wuth extremely low NLRs, indicating excellent rule-out capability. PLRs were modest and similar at PI-RADS ≥ 3 (1.26 vs. 1.42) and 1.88 for both at PI-RADS ≥ 4. PAROS detected more lesions, particularly in the transition zone. Conclusions: PAROS achieved csPCa detection comparable to an experienced radiologist, supporting its role as a decision-support tool in prostate MRI interpretation.

BACKGROUND AND PURPOSE:Whether the performance in detecting local recurrent lesions is similar between multiparametric MRI (mpMRI) and PSMA PET/CT at biochemical failure after radical prostatectomy is controversial and the present study was done to elucidate this point within a prospective phase II on extreme hypofractionation for prostate cancer. MATERIALS AND METHODS:Patients referred for salvage radiotherapy after surgery for pT2-3pN0-x prostate cancer at a single Institution were considered. PSA at biochemical failure had to be higher than 0.2 ng/ml but lower than 2 ng/ml. Patients underwent both mpMRI of the pelvis and PSMA PET/CT. The detection of a discrete lesion within the prostatic fossa was considered the endpoint of the present study. The proportion of patients with positive findings in the two paired groups was compared with the McNemar test, while agreement with Cohen's k test. RESULTS:107 consecutive patients were accrued from September 2022 to September 2024. The mean PSA value at restaging was 0.53 ng/ml. Overall, 68 patients (63.5 %, 95 %CI: 54.1-72.1 %) were found to harbor at least one lesion in the prostatic fossa; 24 (35.3 %), 4 (5.9 %) and 40 (58.8 %) were detected only by mpMRI, only by PSMA PET/CT and by both tests, respectively. The percentage of discordant pairs was higher than expected (28/68, 41.2 %) and significantly different (p < 0.001). The Cohen's agreement between the two imaging modalities was 0.49, p < 0.001. CONCLUSION:mpMRI and PSMA PET/CT show inadequate agreement with the former detecting a significantly higher number of local lesions than the latter with both prognostic and therapeutic implications.

You have accessJournal of UrologyProstate Cancer: Localized: Ablative Therapy I (MP25)1 May 2024MP25-07 DIAGNOSTIC PERFORMANCE OF PI-FAB (PROSTATE IMAGING AFTER FOCAL ABLATION): VALIDATION OF THE SCORING SYSTEM FOR MULTIPARAMETRIC MRI PERFORMED AFTER ABLATIVE TECHNIQUES FOR PROSTATE CANCER Mariaconsiglia Ferriero, Luca Bertini, Riccardo Mastroianni, Gabriele Tuderti, Aldo Brassetti, Alfredo Maria Bove, Leonardo Misuraca, Simone D'Annunzio, Flavia Proietti, Umberto Anceschi, Salvatore Guaglianone, Costantino Leonardo, and Giuseppe Simone Mariaconsiglia FerrieroMariaconsiglia Ferriero , Luca BertiniLuca Bertini , Riccardo MastroianniRiccardo Mastroianni , Gabriele TudertiGabriele Tuderti , Aldo BrassettiAldo Brassetti , Alfredo Maria BoveAlfredo Maria Bove , Leonardo MisuracaLeonardo Misuraca , Simone D'AnnunzioSimone D'Annunzio , Flavia ProiettiFlavia Proietti , Umberto AnceschiUmberto Anceschi , Salvatore GuaglianoneSalvatore Guaglianone , Costantino LeonardoCostantino Leonardo , and Giuseppe SimoneGiuseppe Simone View All Author Informationhttps://doi.org/10.1097/01.JU.0001008692.26556.39.07AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: The PI-FAB (Prostate Imaging after Focal Ablation) score has been recently introduced to evaluate MRI perfomed after ablation of prostate cancer (PCa). We report the diagnostic performance of PI-FAB in a retrospective analysis from a single centre experience of ablative techniques for PCa. METHODS: From February 2021 to September 2023, 174 ablative treatments for PCa were performed. We selected cases who underwent a multiparametric MRI (mpMRI) at 12 month-follow up. All exams were reviewed by our radiologist with expertise in reading MRI, who was blinded to PI-RADS score, and a PI-FAB score was assigned to each case. Patients with suspicious MRI received a rebiopsy, while cases with PI-RADS score ≤ 3 were followed with PSA. Sensitivity, specificity, positive, negative predictive value, accuracy and concordance rate of the two scores were evaluated. Univariable and Multivariable regression analysis were applied to identity predictors of disease recurrence (DR). RESULTS: Fifty-eight patients treated with cryoablation for localized PCa underwent a 12-month mpMRI and a PI-RADS score≥3 was reported in 22 (37.9%) cases. Overall, 2-yr disease free survival probability after cryoablation was 77.3%. (Figure 1) Ten patients, with PI-RADS score≥4 received a rebiopsy and DR was confirmed in 7 cases. (Table 1) Three cases with radiologic evidence of DR (confirmed by PET/CT scan) were treated without biopsy confirmation. PI-FAB score was assigned in 43 cases (not always applicable). Sensitivity, specificity, positive, negative predictive value and accuracy were 83.3%, 91.3%, 71.4%, 95.4%, 89.6% and 75%, 80.6%, 60%, 89.3%, 79.1%, for PI-RADS and PI-FAB score, respectively. Concordance rate of the two scores is 85.7%, with kappa index of 0.68. At univariable regression analysis PI-RADS Score >3 (HR 23.4 CI 3.84-142.5, p=0.001) and PI-FAB=3 (HR 11.1 CI 2.25-54.94, p=0.003) were predictors of DR detection (p=0.02) while at multivariable analysis only PI-RADS score >3 was independent predictor of DR (HR 13.4 CI 1.53-118.3, p=0.019). CONCLUSIONS: Despite some limitations of applicability, PI-FAB score could be a useful tool to identify disease recurrence after ablative treatments. PI-RADS remains the most accurate score for recurrent PCa detection. Download PPT Source of Funding: None © 2024 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 211Issue 5SMay 2024Page: e406 Advertisement Copyright & Permissions© 2024 by American Urological Association Education and Research, Inc.Metrics Author Information Mariaconsiglia Ferriero More articles by this author Luca Bertini More articles by this author Riccardo Mastroianni More articles by this author Gabriele Tuderti More articles by this author Aldo Brassetti More articles by this author Alfredo Maria Bove More articles by this author Leonardo Misuraca More articles by this author Simone D'Annunzio More articles by this author Flavia Proietti More articles by this author Umberto Anceschi More articles by this author Salvatore Guaglianone More articles by this author Costantino Leonardo More articles by this author Giuseppe Simone More articles by this author Expand All Advertisement PDF downloadLoading ...

Background: To investigate the predictive role of dynamic contrast-enhanced-magnetic resonance imaging (DCE-MRI) findings before salvage radiotherapy after radical prostatectomy (RP). Methods: This retrospective study selected patients with biochemical failure (BF) after RP restaged with DCE-MRI. Patients underwent sRT in 30 fractions delivering 66–69 Gy and 73.5 Gy to the prostatic fossa and to the local failure as per DCE-MRI, respectively. Pelvic nodes were treated to 54 Gy in selected patients. The endpoint was BF after sRT. Results: In total, 236 patients were analyzed and 146 (61.9%) had presumed local failure at DCE-MRI: 54.8%, 23.8% and 21.4% were found at the vesico-urethral anastomosis (VUA), the bladder neck and the retro-vesical space, respectively. The presence of a local failure at DCE-MRI halved the risk of BF; VUA-only location and lesion volume were independently correlated with survival without evidence of biochemical failure (bNED) at multivariable analysis. For patients with VUA-only disease up to 0.4 cc, the 4-year-bNED was 94.6% (95%CI: 80.2–98.6%) as opposed to 80.9% (95%CI: 71.6–87.4%) and 73.7% (95%CI: 63.1–81.8%) for other lesions and no macrodisease, respectively. Conclusions: DCE-MRI at restaging for BF after RP provides predictive and therapeutic information. Patients with small lesions at the VUA have an excellent prognosis after sRT.

Background: To assess the pattern of response of presumed local lesions at dynamic contrast enhancement magnetic resonance imaging (DCE-MRI) after salvage radiotherapy (sRT). Methods: This is a prospective study conducted at a single Institution accruing patients with one or more local failures at DCE-MRI after radical prostatectomy between August 2017 and June 2020. Patients underwent exclusive sRT delivering 66–69 Gy and 73.5 Gy in 30 fractions to the whole prostatic fossa and to the local failure(s) seen at DCE-MRI, respectively.Patients were offered DCE-MRI at 3 months intervals after sRT until complete disappearance (CR) of the lesion(s) or up to a maximum of 4 revaluations. Results: 62 patients with 72 nodules were enrolled. All patients underwent the 1st revaluation, and 33 patients (53.2%) showed a CR. The median time to CR was 4.7 months. Four patients did not undergo further testing before achieving a CR and even considering these patients as no responses, the vast majority (87.1%, 95%CI: 78.5–94.4%) of lesions would have completely disappeared by 12 months from the end of sRT.The volume of the lesion at pre-sRT DCE-MRI was an independent predictor of CR at the 1st revaluation (OR: 0.076, 95%CI: 0.009–0.667; p = 0.020) along with time elapsed from sRT (OR: 3.399, 95% CI: 1.156–9.993, p = 0.026). Conclusions: The present study documents the complete disappearance of the vast majority of local lesions after dose-escalated sRT though this requires several months after sRT; timing of CR is at least in part predictable based on the volume of the lesion.Trial registration: Clinicaltrials.gov NCT04703543, registered July 15 2020, retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04703543.

Purpose/Objective(s) To investigate predictors of biochemical failure after salvage radiotherapy (sRT) in the context of a presumed local failure at dynamic contrast-enhancement-magnetic resonance imaging (DCE-MRI) post radical prostatectomy (RP). Materials/Methods All patients referred for sRT at our Institution with a biochemical failure after RP have been consistently offered restaging with both PET/CT and multiparametric MRI since January 2014. Those with a presumed local failure at DCE-MRI as well as no regional/distant disease at PET/CT (either choline and/or PSMA) were selected for the present study. Exclusion criteria were history of androgen deprivation (AD) before sRT and positive nodes at RP. All patients underwent 3T DCE-MRI without endorectal coil and the lesion(s) transferred to the planning CT after co-registration. sRT consisted in 73.5 Gy to the presumed local lesion and 66-69 Gy to the prostatic bed in 30 fxs. Pelvic nodes (PN) were covered to 54 Gy/30 fxs in selected patients. The endpoint of the study was the development of a biochemical failure after sRT defined as a 0.2 ng/ml PSA rise above the nadir. Various covariates (age, pre-RP PSA, pT and pN stages at RP, margins status at RP, ISUP grade group, time from RP to sRT, PSA doubling time, PSA detectability after RP, PSA at sRT, the location, number and volume of the detected recurrence(s), AD use, PN coverage, EUA risk category) were investigated at univariate analysis (UVA) on the time to biochemical failure (bNED-survival). Covariates with a p value <0.2 at UVA were entered a Cox proportional hazards regression analysis. Results Up to June 2020, 146 patients satisfying all selection criteria have been treated with sRT. Median (IQR) PSA at sRT was 0.60 ng/ml (0.38-1.05 ng/ml) and only 17 patients (11.6%) received AD along with sRT. A total of 168 local lesions have been detected, 92 (54.8%), 40 (23.8%) and 36 (21.4%) at the vesicourethral anastomosis (VUA), the bladder neck and the retrovesical space, respectively. At the median (IQR) follow-up of 48.1 months (31.3-60.6 months), 22 biochemical failures have been observed for a 4-yr bNED survival of 84.4% (95%CI: 77.9-90.9%). On UVA, bNED-survival after sRT was significantly more likely for patients with VUA-only lesions (VUA-only vs others, HR=0.307, 95%CI: 0.120-0.784, p=0.014) and with smaller lesions (for every cc, HR: 1.071, 95%CI: 1.025-1.119, p=0.002). These associations remained significant (p< 0.01) on multivariate analysis as well. For patients with VUA-only disease or with lesions smaller than 0.5cc, 4-yr bNED survival rates were 90.7% (95%CI: 83.4-98.0%) and 90.6% (95%CI: 83.9-97.3%), respectively. The 46 patients with both favorable features had a 4-yr bNED rate of 94.6% (95%CI: 87.3-100%). Conclusion These data support local restaging with DCE-MRI before sRT in the setting of a biochemical failure after RP. Patients with VUA-only and/or small volume lesions have an excellent outcome after dose-escalated sRT.

Hepatocellular carcinoma (HCC) is a lethal cancer with increasing incidence, yet the molecular biomarkers that have strong prognostic impact and also hold great therapeutic promise remain elusive.Data mining approaches with a set of publicly accessible databases and immunohistochemistry were used to provide a novel insight into the expression pattern and prognostic significance of the esophageal cancer-related gene (ECRG) family members in HCC.We found that elevated mRNA expression levels of ECRG factors were correlated with better overall survival, relapse-free survival and progression-free survival rates in patients with HCC. Subgroup analyses showed significant associations between ECRG expression and survival outcome in select HCC patients. In addition, immunohistochemical and multivariate analysis confirmed increased ECRG4 expression as an independent prognostic indicator for survival.Our data suggest that ECRG factors have significant impacts on the survival of HCC patients. The expression of ECRG factors may be involved in HCC progression and could serve as novel biomarkers for predicting more accurate prognosis.

Background: We aimed assess the detection rate (DR) of positron emission tomography/computed tomography with two novel tracers in patients referred for salvage radiotherapy (sRT) with a presumed local recurrence at multiparametric magnetic resonance (mpMR) after radical prostatectomy (RP). Methods: The present prospective study was conducted at a single institution between August 2017 and June 2020. Eligibility criteria were undetectable PSA after RP; subsequent biochemical recurrence (two consecutive PSA rises to 0.2 ng/mL or greater); a presumed local failure at mpMR; no distant metastases at 18F-fluorocholine PET/CT (CH/PET); no previous history of androgen deprivation therapy. Patients were offered both 64CuCl2 PET/CT (CU/PET) and 64Cu-PSMA PET/CT (PSMA/PET) before sRT. After image co-registration, PET findings were compared to mpMR ones in terms of DR and independent predictors of DR investigated at logistic regression. Results: A total of 62 patients with 72 nodules at mpMR were accrued. Compared to mpMR (DR = 100%, 95%CI: 94.9–100%), DRs were 47.2% (95%CI: 36.1–58.6%) and 54.4% (95%CI: 42.7–65.7%) for CU/PET and PSMA/PET, respectively (p < 0.001 for both). Both experimental PET/CT performed particularly poorly at PSA levels consistent with early sRT. Conclusions: The two novel radiotracers are inferior to mpMR in restaging the prostatic fossa for sRT planning purposes, particularly in the context of early salvage radiotherapy.

Objective: To assess the predictive role of response on dynamic contrast enhancement on magnetic resonance imaging (DCE-MRI) of visible local lesions in the setting of salvage radiotherapy (sRT) after radical prostatectomy. Methods: All patients referred for sRT for biochemical failure after radical prostatectomy from February 2014 to September 2016 were considered eligible if they had been restaged with DCE-MRI and had been found to have a visible lesion in the prostatic bed, but no distant/nodal disease on choline positron emission tomography (PET)-computed tomography (CT). Eligible patients were contacted during follow-up and offered reimaging with serial DCE-MRI until lesion resolution. Complete response (CR) was defined as the disappearance of the target lesion on DCE-MRI; prostate-specific antigen (PSA) recurrence was defined as a 0.2 ng/mL PSA rise above the nadir. Median follow-up after sRT was 41.5 months (range, 12.1-61.2 months). Results: Fifty-nine patients agreed to undergo repeated DCE-MRI for a total of 64 studied lesions. Overall, 57 lesions (89.1%) showed a CR after 1 (51 patients) or 2 (6 patients) scans, while 7 lesions did not show any change (no response [NR]). At 42 months, no evidence of biochemical disease (bNED) survival was 74.7 +/- 6.4% and 64.3 +/- 21.0% for patients with CR and NR lesions, respectively (hazard ratio [HR], 3.181; 95% confidence interval [CI], 0.157-64.364; p = 0.451). When only patients treated with sRT without androgen deprivation were selected (n = 41), bNED survival rates at 42 months were 72.1 +/- 8.0% and 0, respectively (HR, 52.830; 95% CI, 1.893-1474.110; p = 0.020). Conclusions: Patients whose lesions disappear during follow-up have a better outcome than those with unchanged lesions after sRT alone.

A 62-year-old female patient with no relevant past history was admitted for an asymptomatic periduodenal lesion. Computed tomography (CT) scan showed a 27- × 19- × 21-mm solid nodular mass beneath the III duodenal portion, and absence of the hepatic portion of the inferior vena cava (IVC) was incidentally detected. Hepatic veins drained directly into the right atrium and the suprarenal portion of the IVC drained into a prominent azygos vein (Figure). Uneventful surgical excision of the mass was performed and pathology revealed benign solitary fibrous tumor.

INTRODUCTION:Retroperitoneal Follicular Dendritic Cell Sarcomas represents rare tumours with aggressive biologic behaviour. Accurate diagnosis requires a combination of both morphological and immunohistochemical analyses. PATIENTS AND METHODS:A 61-year-old man was referred to our Department with a left perinephric mass. Computed tomography scan showed a 5.5 cm circumscribed mass in front of the left renal vein abutting the first jejunal loop, with moderate heterogeneous contrast enhancement. Positron emission/computed tomography showed increased focal uptake in the lesion. RESULTS:A retroperitoneal tumor located behind the first jejunal loop was found at laparotomy, encompassing the superior mesenteric vessels. Excision with en-bloc segmental small bowel resection was performed. Morphological and immunohistochemical analyses were consistent with Follicular Dendritic Cell Sarcoma. CONCLUSIONS:Complete surgical resection in specialized multidisciplinary centers represents the treatment of choice for both primary or recurrent lesions since there is still no consensus on the role of adjuvant radio-chemotherapy.

To assess the predictive role of multiparametric MR imaging (mpMRI) in the setting of salvage RT (sRT) for a presumed local failure after radical prostatectomy (RP). This is a cross-sectional study including all patients treated with sRT at a single Institution from Feb 2014 to Sept 2016. All patients had failed biochemically after RP and underwent pre-sRT mpMRI (including a dynamic contrast-enhanced-DCE MRI) on a 3-T system with the evidence of a presumed local recurrence. All patients were treated with a homogeneous approach delivering 73.5 Gy and 69 Gy to the nodule and to the prostatic bed, respectively, in 30 fractions (IGRT-VMAT, SIB technique). Patients underwent a re-evaluation mpMRI at the time of the study. Patients without a complete response (CR), underwent repeated mpRM at 3-6 month-intervals until CR and/or a maximum of 3 repeated mpMRI. CR was defined as complete disappearance of the nodular area of early contrast enhancement in DCE-MRI or persistence of an area of contrast enhancement with a slower wash-in rate and/or a hypointense (more than muscles) appearance on T2-weighted sequence. On baseline DCE-MRI, the wash-in and wash-out were derived from the whole-volume time-intensity curve using home-made software as per Casciani et al, AJR, 2008. The two-sided Mann–Whitney rank test was used to compare the variables. Receiver operating characteristic (ROC) curves were performed for the most significant DCE-MRI parameters. Thirty-seven patients were identified. The mean (SD) time interval between RP and sRT was 71.1 (58.1) mths. At sRT, mean (SD) serum PSA was 1.47 (1.58) ng/ml and the mean (SD) volume of the recurrence delineated on mpMR plus a 8 mm margin (rPTV) was 12.5 cc (6.3 cc). Eleven (29.7%) patients received also androgen deprivation (AD). All patients ended up showing a complete response, 28 (75.7%), 7 (18.9%) and 2 (5.4%) at the 1st, 2nd or 3rd re-eval mpMRI. The mean (SD) time from the end of sRT to CR was 16.5 (10.0) and 24.1 (5.8) mths for patients who responded at the 1st mpMRI (N=28) vs the slower ones (N=9), p= 0.0436. Compared to slower responders, patients achieving a CR at the 1st re-eval mpRM had significantly smaller rPTVs (9.4cc vs 13.1cc, p=0.0214) and a trend towards lower pre-sRT PSA values (1.21 vs 2.28, p=0.06). However, the stronger correlation was found for the wash-out parameter with a lower value highly predicting a delayed response (0.06 s-1 vs -0.99 s-1,continuum, p=0.0087). The sensitivity and specificity of the wash out parameter were 78.6% and 75%, respectively (area under ROC curve 0.808 p=0.0001, cut-off value ≥0.46 s-1). No correlation was found between time to response and AD (p= 0.3030). sRT is highly effective in achieving a complete response at mpMRI. There is a strong correlation between the time to response and baseline wash-out features.

MRI of the gastrointestinal tract is gaining clinical acceptance and is increasingly used to evaluate patients with suspected small-bowel diseases. MRI may be performed with enterography or enteroclysis, both of which combine the advantages of cross-sectional imaging with those of conventional enteroclysis. In this paper, MRI features of primary small-bowel neoplasms, the most important signs for differential diagnosis and the diseases that can be considered as mimickers of small-bowel neoplasms, are discussed.

Last years technological developments in imaging field have made a substantial contribution to diagnosis and staging of rectal cancer. Endorectal ultrasound and MRI with endorectal coil are very useful in rectal cancer initial staging thanks to their ability to distinguish between the rectal wall layers. Major ultrasound limitations are presence of inflammations, desmoplastic reaction and small field of view which limits evaluation of perirectal invasion. MRI with phased-array coils, instead, allows depiction of mesorectum and to assess the distance between tumor and mesorectal fascia. Unfortunately CT shows low accuracy compared to MRI in local staging because it fails to distinguish the rectal wall layers. The criterion used in assessing nodal involvement remains unfortunately still the dimensional one even if new contrast media based on nano-iron particles look promising in this regard On reassessment after chemo-radiotherapy treatment, MRI proved to be a very accurate tool thanks to its ability to detect tumor downstaging, disappearance of mesorectal fascia infiltration or even to show a complete response. The presence of recurrence can be studied by contrast enhanced perfusion-MRI or with good accuracy using PET which, however, presents major technical limitations at present.

OBJECTIVE:The aim of this prospective study was to compare the diagnostic yield of MR enterography (MRE) with small-bowel capsule endoscopy (SBCE) in paediatric patients with suspected Crohn's disease (CD).METHODS:Paediatric patients with suspected CD were considered eligible to be enrolled in the study. All patients underwent diagnostic work-up including 1.5-T MRE, ileo-colonoscopy and oesophagogastroduodenoscopy. SBCE was not performed if MRE showed SB stricture or extra-intestinal findings consistent with symptoms.RESULTS:Sixty consecutive paediatric patients (36 male; average age 14) were enrolled into the study. A positive diagnosis for CD was made in 19 patients, 29 had a negative result and 12 were affected by other gastro-intestinal conditions. SBCE was performed in 37 patients (61.7%); 23 patients were excluded (strictures in five, extra-intestinal findings in 11 and parents' refusal in seven cases). The accuracy, sensitivity, and specificity of MRE and SBCE were 98.3%, 100%, 97.6%, and 91.9%, 90.9%, 92.3%, respectively.CONCLUSION:Both MRE and SBCE are accurate methods for patients with suspected CD. MRE can be used as a primary imaging technique in suspected CD, in that it allows access to the ileal stricture, which forms a contra-indication for SBCE and provides extra-intestinal information.