Sextant Systematic Biopsy Versus Extended 12-Core Systematic Biopsy in Combined Biopsy for Prostate Cancer.

BACKGROUND: This study assessed the comparative effectiveness of sextant and extended 12-core systematic biopsy within combined biopsy for the detection of prostate cancer. METHODS: Patients who underwent combined biopsy targeting lesions with a Prostate Imaging Reporting and Data System (PI-RADS) score of 3-5 were assessed. Two specialists performed all combined cognitive biopsies. Both specialists performed target biopsies with five or more cores. One performed sextant systematic biopsies, and the other performed extended 12-core systematic biopsies. A total of 550 patients were analyzed. RESULTS: Cases requiring systematic biopsy in combined biopsy exhibited a significant association with age ≥ 65 years (odds ratio [OR], 2.32; 95% confidence interval [CI], 1.25-4.32; P = 0.008), PI-RADS score (OR, 2.32; 95% CI, 1.25-4.32; P = 0.008), and the number of systematic biopsy cores (OR, 3.69; 95% CI, 2.11-6.44; P < 0.001). In patients with an index lesion of PI-RADS 4, an extended 12-core systematic biopsy was required (target-negative/systematic-positive or a greater Gleason score in the systematic biopsy than in the targeted biopsy) (P < 0.001). CONCLUSION: During combined biopsy for prostate cancer in patients with PI-RADS 3 or 5, sextant systematic biopsy should be recommended over extended 12-core systematic biopsy when an effective targeted biopsy is performed.

Transrectal ultrasound features and biopsy outcomes of transition PI-RADS 5.

BACKGROUND: Transition Prostate Imaging and Reporting and Data System (PI-RADS) 5 is easily detected owing to typical magnetic resonance imaging features. However, it is unclear as to how transition PI-RADS 5 appears on transrectal ultrasound (TRUS). PURPOSE: To assess TRUS features of transition PI-RADS 5 and outcomes of TRUS-guided target biopsy. MATERIAL AND METHODS: Between March 2014 and November 2018, 186 male patients underwent TRUS-guided biopsy of PI-RADS 5. Of them, 82 and 104were transition and peripheral PI-RADS 5, respectively. Transition and peripheral PI-RADS 5 were compared according to echogenicity (hyperechoic or hypoechoic) and hypoechoic rim (present or absent). Each tumor was targeted with TRUS based on TRUS features. Significant (Gleason score ≥7) and insignificant (Gleason score 6) cancer detection rates (CDRs) were compared between transition and peripheral PI-RADS 5. Standard reference was biopsy examination. Fisher's exact test was used for statistical analysis. RESULTS: Transition PI-RADS 5 was hyperechoic in 89.0% (73/82) and had a hypoechoic rim in 97.6% (80/82), whereas peripheral PI-RADS 5 was hypoechoic in 99.0% (103/104) and had a hypoechoic rim in 26.9% (28/104) (both, P<0.0001). The significant CDRs of transition and peripheral PI-RADS 5 were 56.1% (46/82) and 65.4% (68/104), respectively (P=0.2263). However, the insignificant CDRs of these categories were 22.0% (18/82) and 8.7% (9/104), respectively (P=0.0123). CONCLUSION: Transition PI-RADS 5 tends to have hyperechoic echogenicity and a hypoechoic rim. These findings help to target the transition PI-RADS 5 using TRUS. However, transition PI-RADS 5 is confirmed more frequently as insignificant cancer than peripheral PI-RADS 5.

Necessity of differentiating small (< 10 mm) and large (≥ 10 mm) PI-RADS 4.

PURPOSE: Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) provides reasonable performance in detecting significant cancers. Still, it is unclear about whether all PI-RADS 4 lesions show the same cancer detection rate (CDR) regardless of tumor size. The aim was to compare the CDRs of small (< 10 mm) and large (≥ 10 mm) PI-RADS 4. METHODS: After magnetic resonance imaging (MRI) was performed in 684 men, a radiologist interpreted the MR images and detected 281 index lesions categorized as PI-RADS 4 in 281 men. PI-RADS 4 lesions were divided into small and large groups on size of 10 mm. Overall and significant CDRs were compared between the groups. A significant cancer was defined as one with Gleason score (GS) ≥ 7 or tumor volume ≥ 0.5 ml. Tumor volumes were roughly calculated as πr34/3 (π = 3.14 and r = a half of tumor size) and were compared between the groups. Standard reference was a biopsy examination. Fisher's exact and Mann-Whitney tests were used for statistical analysis. RESULTS: The overall CDRs of small and large groups were 39.0% (53/136) and 59.3% (86/145), respectively, (p = 0.0008). The median tumor volumes of cancer-proven small and large groups were 0.18 ml (0.01-0.38 ml) and 0.70 ml (0.52-1.44 ml), respectively (p < 0.0001). Using GS or tumor volume, the significant CDRs of these groups were 26.5% (36/136) and 59.3% (86/145), respectively (p < 0.0001), and using GS alone, 26.5% (36/136) and 39.3% (57/145), respectively (p = 0.0232). CONCLUSIONS: PI-RADS 4 lesions should be sub-divided on size of 10 mm because of different significant CDRs.

Diagnostic Performance of Mass Enhancement on Dynamic Contrast-Enhanced MRI for Predicting Clinically Significant Peripheral Zone Prostate Cancer.

OBJECTIVE. Current criteria for positive findings on dynamic contrast-enhanced MRI (DCE-MRI) are unclear. We compared the diagnostic performance of mass enhancement on DCE-MRI versus conventional DCE-MRI criteria for identifying clinically significant prostate cancer (csPCa) in the peripheral zone (PZ). MATERIALS AND METHODS. A total of 173 consecutive patients with MRI- and surgically proven prostate cancer (PCa) were evaluated. Two readers independently interpreted DCE-MRI examinations of the PZ. Criteria denoting a positive DCE-MRI examination included conventional criteria from the Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) and mass enhancement. The diagnostic performance of and interreader agreement for the two types of enhancement criteria in identifying csPCa in the PZ that met Epstein criteria were investigated. RESULTS. The proportion of csPCa in the PZ was 69.3% (120/173). For both readers, the specificity and positive predictive value of mass enhancement were increased compared with conventional enhancement criteria (specificity, 75.5% vs 5.7% [for reader 1] and 84.9% vs 30.2% [for reader 2], respectively; positive predictive value, 87.1% vs 70.6% [for reader 1] and 91.5% vs 75.3% [for reader 2], respectively). The AUC value of mass enhancement was higher than that of conventional criteria (for reader 1, 0.744 [95% CI, 0.672-0.807] vs 0.528 [95% CI, 0.451-0.605] [p < 0.001], respectively; for reader 2, 0.783 [95% CI, 0.714-0.842] vs 0.602 [95% CI, 0.497-0.700] [p < 0.001], respectively). The weighted kappa value for agreement between the two readers was 0.206 for conventional criteria and 0.613 for mass enhancement. CONCLUSION. PZ lesions with mass enhancement on DCE-MRI are more likely to be csPCa. This enhancement pattern may need to be considered as one of the criteria in PI-RADS.

Renal Angiomyolipoma Based on New Classification: How to Differentiate It From Renal Cell Carcinoma.

OBJECTIVE: The purpose of this article is to describe useful imaging features for differentiating angiomyolipoma (AML) subtypes from renal cell carcinoma subtypes. CONCLUSION: A newer radiologic classification of renal AML consists of fat-rich AML (≤ -10 HU), fat-poor AML (> -10 HU; tumor-to-spleen ratio < 0.71; signal intensity index, > 16.5%), and fat-invisible AML (> -10 HU; tumor-to-spleen ratio, > 0.71; signal intensity index, < 16.5%). Each subtype must be differentiated from the renal cell carcinoma subtype because of overlapping imaging features.

Endoscopic closure of iatrogenic colon perforation using dual-channel endoscope with an endoloop and clips: methods and feasibility data (with videos).

BACKGROUND: Colon perforation is the most serious complication associated with colonoscopic procedures. We performed a novel purse-string suture technique to close the iatrogenic colonic perforation using dual-channel endoscope with an endoloop and clips. METHODS: Iatrogenic colon perforations developed during diagnostic colonoscopy referred to a tertiary hospital over 10 years were considered for this endoscopic closure. An endoloop was inserted through the left channel of the endoscope and placed around the defect. The first clip was placed at the proximal site of the defect through the other channel of the endoscope, and the endoloop was anchored on the mucosa around the defect. Then, subsequent clips were placed next to previous clips and the endoloop was fixed. After the defect was encircled by the endoloop and clips, the rim of the opening was approximated by fastening the endoloop with a purse-string technique. RESULTS: A total of 8 patients were admitted to our hospital because of iatrogenic colon perforations during diagnostic colonoscopy. Of these, 2 underwent laparoscopic surgery and 6 underwent endoscopic closure by this novel purse-string suture technique. The estimated diameters of the perforations were 20 mm. All cases were successfully treated in the endoscopy unit without sedation or general anesthesia, and recovered without any complication or subsequent operation. Abdominal pain had nearly resolved within 3 days after the procedure in all patients, and only mild peritonitis was observed. CONCLUSIONS: Iatrogenic colon perforation can be treated with a purse-string suture technique using dual-channel endoscope with an endoloop and clips. This technique can be useful for relatively large colon perforations associated with diagnostic colonoscopy.

Minimization of Wound With the Assistance of a Needle Grasper in Single-Incision Laparoscopic Appendectomy.

Background. Technical difficulties and pain from large wounds have prevented the widespread use of single-incision laparoscopic appendectomy (SILA). This study aimed to evaluate the efficacy of our newly developed needle grasper (Endo Relief)-assisted SILA (NASILA). Methods. For NASILA, about a 12-mm umbilical incision was made, and a glove port was introduced. A needle grasper was then introduced through a 2.5-mm wound on the suprapubic area. For SILA, a 2.5-cm transumbilical wound was made. The medical records of patients who underwent SILA or NASILA from June 2017 to September 2017 were retrospectively reviewed. Operative and short-term postoperative outcomes and results of telephone interviews for scars were compared. Results. A total of 49 patients in the SILA group (male: 40.8%) and 12 in the NASILA group (male: 50.0%) were included. Appendicitis status (not perforated:perforated without abscess:perforated with abscess) was significantly different between the 2 groups (SILA vs NASILA, 30:18:1 vs 4:6:2, P = .027). Additional trocars were inserted in 9 patients (18.4%) of the SILA group. The operative time was significantly shorter (43.3 ± 33.6 vs 54.1 ± 15.6 minutes, P = .012), and the highest numerical pain intensity score during the first 24 hours after surgery was significantly lower (2.4 ± 0.7 vs 3.0 ± 0.9, P = .038) in the NASILA group than in the SILA group. Hospital stay, postoperative complications, and complaint of scar were not significantly different between the 2 groups. Conclusions. NASILA was not inferior to SILA regarding cosmetic results. Operative convenience is higher in NASILA than in SILA, and the smaller surgical wound in NASILA minimizes postoperative pain.

RFA versus robotic partial nephrectomy for T1a renal cell carcinoma: a propensity score-matched comparison of mid-term outcome.

OBJECTIVE: To compare oncological and functional mid-term outcomes following robotic partial nephrectomy (RPN) and radiofrequency ablation (RFA) for treating T1a renal cell carcinoma (RCC) using propensity score-matching. METHODS: Between December 2008-April 2016, 63 patients from each treatment group were propensity score-matched for age, sex, American Society of Anesthesiologists score, tumour size, tumour laterality, tumour histology, R.E.N.A.L. nephrometry score and preoperative estimated glomerular filtration rate (eGFR). Post-treatment follow-up periods for RPN and RFA ranged from 1-90 months (median, 24.6) and 1-65 months (21), respectively. Tumour location, percentage of eGFR preservation and 2-year recurrence-free survival rate were compared between groups. RESULTS: Exophytic and endophytic RCC occurred in 73.0 % (46/63) and 27.0 % (17/63) of the RPN group, and 52.4 % (33/63) and 47.6 % (30/63) of the RFA group, respectively (p=0.017). There was 91.7 % preservation of eGFR in the RPN group and 86.8 % in the RFA group (p=0.088). Two-year recurrence-free survival rate was 100 % in the RPN and 95.2 % in the RFA group (p=0.029). CONCLUSIONS: RPN provides a higher recurrence-free survival rate than RFA. However, RFA is a better treatment option for an endophytic or recurrent RCC that is difficult to treat with RPN. KEY POINTS: • RPN provides a higher recurrence-free survival rate than RFA. • Unlike RPN, repeat RFA is easy to perform for recurrent RCC. • Endophytic RCC could be better treated with RFA.

Feasibility of Selective Lateral Node Dissection Based on Magnetic Resonance Imaging in Rectal Cancer After Preoperative Chemoradiotherapy.

BACKGROUND: Lateral pelvic node metastasis is one of the major causes of local recurrence in advanced rectal cancer after preoperative chemoradiotherapy (CRT). However, lateral pelvic node dissection (LPND) is still a challenging surgical procedure in terms of surgical morbidity. This study aimed to investigate the feasibility and safety of LPND in patients with advanced rectal cancer after preoperative CRT. MATERIALS AND METHODS: Records of 80 consecutive patients who underwent total mesorectal excision (TME) with LPND for initially enlarged lateral pelvic nodes (LPNs) (short-axis diameter ≥5 mm on magnetic resonance imaging before preoperative CRT) between 2011 and 2016 were retrospectively reviewed. Surgical outcomes of these patients were compared with those of 281 patients who underwent TME alone. RESULTS: Ninety-nine LPND procedures were performed, including 19 bilateral LPNDs. Pathologically proven LPN metastasis was identified in 32 (32.3%) LPND cases after preoperative CRT. Multiple (odds ratio = 12.908, 95% confidence interval: 3.355-49.660, P < 0.001) and persistently enlarged LPNs (odds ratio = 27.093, 95% confidence interval: 6.072-120.896, P < 0.001) were independently associated with LPN metastasis. The rates of overall postoperative 30-d morbidity (42.5% versus 32.4%, P = 0.093) and urinary retention (11.3% versus 7.1%, P = 0.230) were similar between the TME with LPND and TME-only groups. CONCLUSIONS: The postoperative morbidity of TME with LPND was comparable with TME-only group. The rate of LPN metastasis remained high after preoperative CRT, especially in patients with multiple or persistently enlarged LPNs.

Bacterial culture and antibiotic susceptibility in patients with acute appendicitis.

PURPOSE: Essential treatment of acute appendicitis is surgical resection with the use of appropriate antibiotics. In order to effectively treat acute appendicitis, it is important to identify the microorganism of acute appendicitis and evaluate the effective antibiotics. METHODS: A total of 694 patients who underwent appendectomy for acute appendicitis and had positive microbial result between 2006 and 2015 were recruited. For microbial assessment, luminal contents of the appendix were swabbed after appendectomy. In patients with periappendiceal abscess, the specimens were obtained from abscess fluid. The patient characteristics, operative data, use of antibiotics, the results of microbiology, and postoperative morbidities including surgical site infection (SSI) were retrospectively reviewed. RESULTS: The mean age was 38.2 (± 19.8) years, and 422 patients (60.8%) were male. Most of the operations were performed by conventional laparoscopy (83.1%), followed by single-port laparoscopy (11.8%). The most common microorganism was Escherichia coli (64.6%), which was susceptible to amoxicillin/clavulanate, ciprofloxacin, most cephalosporins, piperacillin/tazobactam, and imipenem. The second most common microorganism was Pseudomonas aeruginosa (16.4%), which was resistant to amoxicillin/clavulanate and cefotaxime. The rate of postoperative morbidity was 8.6%, and the most common type was superficial SSI (6.2%), followed by ileus (1.2%), gastroenteritis (0.7%), and organ/space SSI (0.3%). P. aeruginosa (odds ratio = 2.128, 95% confidence interval 1.077-4.206, P = 0.030) was the only significant microorganism associated with SSI according to multivariate analysis adjusting for other clinical factors. CONCLUSIONS: In perforated appendicitis, the use of empirical antibiotics seems to be safe. In some cases of Pseudomonas infection, adequate antibiotics should be considered.

Low-dose CT protocols for guiding radiofrequency ablation for the treatment of small renal cell carcinomas.

OBJECTIVE: Computed tomography (CT)-guided radiofrequency ablation (RFA) results in a high radiation dose. This study aimed to assess low-dose CT protocols for guiding RFA and oncologic outcomes for the treatment of small renal cell carcinoma (RCC). MATERIALS AND METHODS: Between December 2011 and December 2014, CT-guided RFA was performed in 31 patients with 31 biopsy-proven RCCs (median, 2.1 cm). RFA included planning, targeting, monitoring and survey phases. The dose length product (DLP), CT dose index volume (CTDIvol), effective dose, number of scans, scan range, tube current and exposure time of RFA phases were compared. The 3-year recurrence-free survival rate was recorded. Nonparametric or parametric repeated-measures ANOVA with Dunn's or Tukey-Kramer multiple comparisons and Kaplan-Meier analysis were used for statistical analysis. RESULTS: The median total DLP, CTDIvol and effective dose of CT-guided RFA procedures per session were 1238.8 mGy (range 517.4-3391.7 mGy), 259.7 mGy (10.7-67.9 mGy) and 18.6 mSv (7.8-50.9 mSv), respectively. The median DLP, CTDIvol, effective dose, number of scans, tube current and exposure time during the targeting phase were higher than those during the other phases (p < 0.001). The scan range in the targeting phase was the same as that in the monitoring phase (p > 0.05) but smaller than those in the planning and survey phases (p < 0.001). The 3-year recurrence-free survival rate was 96.7%. CONCLUSIONS: Low-dose CT protocols for guiding RFA may reduce radiation dose without compromising oncologic outcomes. Reducing the number of scans during the targeting phase contributes to dose reduction.

Comparison of General Anesthesia and Conscious Sedation During Computed Tomography-Guided Radiofrequency Ablation of T1a Renal Cell Carcinoma.

PURPOSE: Percutaneous radiofrequency ablation is so painful that this treatment requires pain control such as conscious sedation or general anesthesia. It is still unclear which type of anesthesia is better for treatment outcomes of renal cell carcinoma. This study aimed to compare general anesthesia and conscious sedation in treating patients with renal cell carcinoma with radiofrequency ablation. METHODS: Between 2010 and 2015, 51 patients with biopsy-proven renal cell carcinomas (<4 cm) were treated with computed tomography-guided radiofrequency ablation. General anesthesia was performed in 41 and conscious sedation was performed in 10 patients. Tumour size, local tumour progression, metastasis, major complication, effective dose, glomerular filtration rate difference, and recurrence-free survival rate were compared between these groups. RESULTS: The mean tumour size was 2.1 cm in both groups (P = .673). Local tumour progression occurred in 0% (0 of 41) of the general anesthesia group, but in 40% (4 of 10) of the conscious sedation group (P = .001). Metastases in these groups occurred in 2.4% (1 of 41) of the general anesthesia group and 20% (2 of 10) of the conscious sedation group (P = .094). No major complications developed in either group after the first radiofrequency ablation session. The mean effective doses in these groups were 21.7 mSv and 21.2 mSv, respectively (P = .868). The mean glomerular filtration rate differences in the general anesthesia and conscious sedation groups were -13.5 mL/min/1.73 m2 and -19.1 mL/min/1.73 m2, respectively (P = .575). Three-year recurrence-free survival rates in these groups were 97.6% and 60.0%, respectively (P = .001). CONCLUSIONS: General anesthesia may provide better intermediate outcomes than conscious sedation in treating small renal cell carcinomas with radiofrequency ablation.

Postoperative Outcome of Cystic Renal Cell Carcinoma Defined on Preoperative Imaging: A Retrospective Study.

PURPOSE: We evaluated the postoperative outcome of cystic renal cell carcinoma defined on preoperative computerized tomography. We also sought to find the optimal cutoff of the cystic proportion in association with patient prognosis. MATERIAL AND METHODS: In this institutional review board approved study with waiver of informed consent, 1,315 patients were enrolled who underwent surgery for a single renal cell carcinoma with preoperative computerized tomography. The cystic proportion of renal cell carcinoma was determined on computerized tomography. The optimal cutoff of the cystic proportion was explored regarding cancer specific survival. Renal cell carcinomas were categorized as cystic or noncystic renal cell carcinoma according to a conventional cutoff (ie cystic proportion 75% or greater) and an optimal cutoff. Postoperative outcomes were then compared between the 2 groups. Multivariate Cox regression analysis was performed to determine the independent predictor of cancer specific survival. RESULTS: Of the 1,315 lesions 107 (8.1%) were identified as cystic renal cell carcinoma according to a conventional cutoff. The postoperative outcome of cystic renal cell carcinoma was significantly better than that of noncystic renal cell carcinoma (p <0.001). Neither metastasis nor recurrence developed after surgery in patients with cystic renal cell carcinoma. In association with the cancer specific survival rate, the optimal cutoff of the cystic proportion was 45% and 197 cases (15.0%) were accordingly defined as cystic renal cell carcinoma. On Cox regression analysis, a cystic proportion of 45% or greater of the renal cell carcinoma was an independent predictor of a favorable outcome regarding cancer specific survival (HR 0.34, p = 0.03). CONCLUSIONS: Cystic renal cell carcinoma defined on preoperative computerized tomography is associated with low metastatic potential and favorable outcomes after surgery. Particularly, a cystic proportion of 45% or greater is an independent prognostic factor for favorable survival.

Ultimate Clinical Outcomes of Appendiceal Mucinous Neoplasm of Uncertain Malignant Potential.

BACKGROUND: The clinical outcome of appendiceal mucinous neoplasm (AMN) is not well understood. This study aimed to compare the long-term outcome for the uncertain malignant potential (UMP) subtype of AMNs with those of the mucinous adenoma (MA) and mucinous adenocarcinoma (MAC) subtypes. METHODS: In this study, AMNs were classified into three groups (MA, UMP, and MAC), and clinical characteristics, overall survival (OS), and progression-free survival (PFS) were compared among the three groups. RESULTS: The study included 65 AMN patients (26 MA, 20 UMP, and 19 MAC patients). The median follow-up period was 87 months (range 0.3-311.0) months. The symptoms at diagnosis and the presence of pseudomyxoma peritonei were more common in the MAC group than in the MA group (P = 0.012) or the UMP group (P < 0.001). The 5-year OS rates were 95.5% for the MA group, 93.8% for the UMP group, and 78.3% for the MAC group (P < 0.001), and the 5-year PFS rates were 95.2% for the MA group, 95% for the UMP group, and 36.8% for the MAC group (P < 0.001). Thus, OS and PFS did not differ significantly in the MA and UMP groups (P = 0.884 and 0.345, respectively). In contrast, the OS and PFS of the MAC group were worse than in the MA group (P = 0.017 and <0.001, respectively) or the UMP group (P < 0.001 and 0.001, respectively). CONCLUSIONS: The long-term outcome for UMP tumors is similar to that for MA tumors and significantly better than for MAC tumors.

Role of PI-RADSv2 with multiparametric MRI in determining who needs active surveillance or definitive treatment according to PRIAS.

PURPOSE: To evaluate the role of Prostate Imaging Reporting and Data System v. 2 (PI-RADSv2) in triaging patients with prostate cancer according to Prostate Cancer Research International: Active Surveillance (PRIAS). MATERIALS AND METHODS: Between January 2012 and December 2014, 456 patients with biopsy-proven cancer underwent multiparametric 3T magnetic resonance imaging (MRI) using T2 -weighted, diffusion-weighted, and dynamic contrast-enhanced MRI sequences, and then radical prostatectomy. Two radiologists independently reviewed MR images using PI-RADSv2. For AS, PRIAS required clinical stage

Accuracy of preoperative multiparametric magnetic resonance imaging for prediction of unfavorable pathology in patients with localized prostate cancer undergoing radical prostatectomy.

INTRODUCTION: We investigated the accuracy of multiparametric MRI (mpMRI) for preoperative staging and its influence on the determination of neurovascular bundle sparing and disease prognosis in patients with localized prostate cancer. METHODS: We reviewed 1045 patients who underwent radical prostatectomy with preoperative mpMRI at a single institution. Clinical local stages determined from mpMRI were correlated with preoperative and postoperative pathological outcomes. RESULTS: The sensitivity and specificity to diagnose seminal vesicle invasion (SVI) on mpMRI were 43.8 and 95.4 %, respectively. The negative predictive value was 78.9 %. The sensitivity and specificity to diagnose extracapsular extension (ECE) were 54.5 and 80.5 %, respectively. The overall sensitivity and specificity of diagnosing pathological T3 or higher were 52.6 and 82.1 %, respectively. Non-organ-confined disease determined by mpMRI was significantly associated with positive surgical margin and pathological T3 disease on multivariate analysis. Preoperative adverse findings on mpMRI were significantly associated with performance of the non-nerve-sparing technique. CONCLUSION: mpMRI did not show outstanding diagnostic accuracy relative to our expectations in predicting SVI or ECE preoperatively. However, adverse findings on preoperative mpMRI were significantly related to worse postoperative pathological outcomes as well as postoperative biochemical recurrence.

Renal Angiomyolipoma: Radiologic Classification and Imaging Features According to the Amount of Fat.

OBJECTIVE: The purposes of this article are to introduce the radiologic classifications of renal angiomyolipoma (AML) and the clinical implications, to show the imaging features of each type of AML, and to describe which types of AML should be biopsied. CONCLUSION: Renal AML can be classified according to amount of fat as fat rich, fat poor, or fat invisible. To detect fat, one needs to thoroughly evaluate the entire AML by controlling the size and shape of the ROI. Fat-invisible AML should be biopsied, and fat-poor AML requires further investigation to determine whether biopsy is necessary to differentiate it from renal cell carcinoma. If differentiation between AML and renal cell carcinoma is not clear with CT and MRI, percutaneous biopsy may be performed.

Parametrial Involvement on Magnetic Resonance Imaging Has No Effect on the Survival of Early-Stage Cervical Cancer Patients.

OBJECTIVES: Parametrial involvement (PMI) in patients with cervical cancer is known to be an unfavourable prognostic factor. The purpose of this study was to investigate the prognostic significance of PMI on magnetic resonance imaging (MRI) in patients with early-stage cervical cancer. METHODS: Three hundred three patients with stage IB or IIA cervical cancer treated by adjuvant radiotherapy or concurrent chemoradiotherapy following primary surgery from 2001 to 2011 were enrolled in this study. We reviewed preoperative MRI and pathologic findings and compared recurrence and survival of group defined according to PMI status. RESULTS: There were 73 patients (24.1%) with PMI based on MRI and 52 patients (17.2%) with PMI based on surgical pathology. The accuracy of MRI for detecting PMI was 77.2% (sensitivity, 53.8%; specificity, 82.1%). In all patients, pathology-based evidence of PMI had a negative effect on both 5-year disease-free survival (73.2% vs 85.3%, P = 0.048) and 5-year overall survival (76.6% vs 91.4%, P = 0.009), but PMI on MRI did not have a significant effect on survival. In subgroups defined according to PMI status on MRI and surgical pathology, subgroups with pathology-based evidence of PMI showed a trend of a lower survival rate, regardless of PMI on MRI, but without statistical significance. CONCLUSIONS: Unlike pathologic results, PMI on MRI was not associated with recurrence or survival in patients with early-stage cervical cancer.

Prostate diffusion-weighted imaging at 3T: effect of intravenous gadobutrol administration.

OBJECTIVE: To investigate whether gadolinium-based contrast agent (GBCA) administration significantly affects diffusion-weighted imaging (DWI) at 3 T in the evaluation of prostate cancer and benign tissue. METHOD: Thirty-four consecutive patients with surgically proven prostate cancer underwent preoperative DWI at 3 T before and after GBCA administration. Exponential apparent diffusion coefficient (EADC) and ADC maps were developed from DWI data. The ADC and EADC values pre- and post-contrast were measured in the cancer and benign tissue, respectively. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were evaluated on pre- and post-contrast DWI. RESULTS: The ADC and EADC values of the cancer and benign transition zone were not significantly different between pre- and post-contrast, respectively (P > 0.05), while those in the benign peripheral zone were significantly different (P = 0.030 and 0.037, respectively). In all tissues, the SNRs and CNRs of the DWI, ADC map and EADC map were not significantly different between pre- and post-contrast (P > 0.05). Between pre- and post-contrast, ADC and EADC values showed excellent agreement (intraclass correlation coefficient ≥ 0.894) and variability of ≤3.2 %. CONCLUSION: Prostate 3 T-DWI after GBCA administration may be used without a significant difference in SNR or CNR, with minimal variability of the cancer ADC and EADC values. KEY POINTS: • ADCs and EADCs have excellent agreement before and after gadobutrol administration. • SNRs of prostate DWI are similar before and after gadobutrol administration. • CNRs of cancers are similar between pre- and post-contrast DWI.

Single-phase DECT with VNCT compared with three-phase CTU in patients with haematuria.

OBJECTIVE: To retrospectively evaluate the diagnostic performance of single-phase dual-energy CT (DECT) with virtual non-contrast CT (VNCT) compared with three-phase CT urography (CTU) in patients with haematuria. METHODS: A total of 296 patients underwent three-phase CTU (NCT at 120 kVp; nephrographic phase and excretory phase DECTs at 140 kVp and 80 kVp) owing to haematuria. Diagnostic performances of CT scans were compared for detecting urothelial tumours and urinary stones. Dose-length product (DLP) was compared in relation to single-phase DECT and three-phase CTU Dose-length product (DLP) was compared in relation to single-phase DECT and three-phase CTU. RESULTS: Sensitivity and specificity for tumour were 95 % (19/20) and 98.9 % (273/276) on CTU, 95 % (19/20) and 98.2 % (271/276) on nephrographic phase DECT, and 90 % (18/20) and 98.2 % (271/276) on excretory phase DECT (P > 0.1). Of the 148 stones detected on NCT, 108 (73 %) and 100 (67.6 %) were detected on nephrographic phase and excretory phase VNCTs, respectively. The mean size of stones undetected on nephrographic and excretory VNCTs was measured as 1.5 ± 0.5 mm and 1.6 ± 0.6 mm, respectively. The mean DLPs of three-phase CTU, nephrographic phase DECT and excretory phase DECT were 1076 ± 248 mGy · cm, 410 ± 98 mGy · cm, and 360 ± 87 mGy · cm, respectively (P < 0.001). CONCLUSIONS: Single-phase DECT has a potential to replace three-phase CTU for detecting tumours with a lower radiation dose. KEY POINTS: • Single-phase DECT with virtual NCT may replace three-phase CTU for detecting tumours. • Virtual NCT cannot replace NCT for detecting small urinary stones. • Single-phase DECT may reduce the radiation dose by 62-67 % compared to three-phase CTU. • Nephrographic phase DECT is superior to excretory phase DECT for assessing haematuria.