Urothelial Carcinoma of the Renal Pelvis with Synchronous Ipsilateral Collecting Duct Carcinoma: Two Case Reports.

Synchronous renal malignancies are seldom encountered or diagnosed post-renal resection. A combination of renal cell carcinoma (RCC) and urothelial carcinoma (UC) is most commonly reported. Typically, the RCC subtype is clear-cell RCC; however, a combination of collecting duct carcinoma (CDC) and UC has rarely been reported in the existing literature. Here, we present two cases of synchronous renal malignancy, specifically a combination of CDC and UC, in the ipsilateral kidney.

Multilocular Cystic Renal Neoplasm of Low Malignant Potential: A Case Report and Literature Review.

Multilocular cystic renal neoplasm of low malignant potential (MCRNLMP) is a rare subtype of renal cell carcinoma that has a favorable outcome. Most cases of MCRNLMP usually present as distinct multilocular cystic lesions; however, they may appear as small complicated cysts with hemorrhagic components. Herein, we present a case of MCRNLMP and provide a review of the literature.

Risk Factors for Renal Function Impairment Following Radiofrequency Ablation of Renal Tumors.

Purpose: To evaluate the various factors that affect renal function following percutaneous radiofrequency ablation (RFA) therapy in patients with renal tumors. Materials and Methods: Between 2010 and 2018, 91 patients diagnosed with renal tumors using ultrasonography and CT-guided RFA were enrolled. We retrospectively investigated the serum creatinine (SCr) level and estimated glomerular filtration rates immediately prior to RFA and during post-treatment follow-up. The patients were divided into two groups based on the degree of change in SCr level (0.3 mg/dL). Group comparisons were performed using univariable and multivariable logistic regression analyses to determine the factors impacting renal function. Results: Impaired renal function was associated with solitary kidney, chronic kidney disease (CKD) over stage 3, and pyeloureteral injury. Sex, age, other cancers, tumor size, location, growth pattern, and proximity to the collecting system were not significantly associated with impaired renal function. There was a difference in the overall change over time between the association with and without solitary kidney, CKD stage 3, and pyeloureteral injury. Conclusion: Among the medical conditions present prior to RFA, solitary kidney and CKD over stage 3 could be considered as risk factors for impaired renal function. Post-procedural pyeloureteral injury can also be considered a risk factor.

[Urothelial Carcinoma of the Bladder: Radiologic Perspective]. / 방광 요로상피세포암: ì˜ìƒì˜í•™ì  ê´€ì .

Bladder cancer is a relatively common cancer type, with a high recurrence rate, that can be often encountered in the imaging study. Accurate diagnosis and staging have a significant impact on determining treatment and evaluating prognosis. Bladder cancer has been evaluated by transurethral resection of bladder tumor for clinical staging and treatment, but it is often understaged when compared with final pathologic result by radical cystectomy. If the location, size, presence of muscle invasion, lymph node metastasis, distant metastasis, and presence of upper urinary tract cancer can be accurately diagnosed and evaluated in an imaging study, it can be treated and managed more appropriately. For an accurate diagnosis, radiologists who evaluate the images must be aware of the characteristics of bladder cancer as well as its types, imaging techniques, and limitations of imaging studies. Recent developments in MRI with functional imaging have improved the quality of bladder imaging and the evaluation of cancer. In addition, the Vesical Imaging Reporting and Data System was published to objectively assess the possibility for muscle invasion of cancer. Radiologists need to know the types of bladder cancer treatment and how to evaluate the changes after treatment. In this article, the characteristics of bladder urothelial carcinoma, various imaging studies, and findings are reviewed.

Assessment of clinical and radiologic differences between small and large adrenal pheochromocytomas.

OBJECTIVE: To evaluate differences in clinical and radiologic features of small and large pheochromocytomas. MATERIALS AND METHODS: This study included 39 patients with adrenal pheochromocytomas. Several clinical and radiologic features were statistically analyzed and compared between small and large pheochromocytomas. RESULTS: No significant differences were found in clinical features between them. Small pheochromocytomas had more relatively homogeneous attenuation although large pheochromocytomas had more cystic or necrotic changes. CONCLUSIONS: Pheochromocytomas tend to have different CT imaging features mimicking other tumors according to the size of the tumors. However, clinical features, CT imaging characteristics, and radioisotope activity are not different between small and large pheochromocytomas.

Contrast-induced nephropathy in patients undergoing intravenous contrast-enhanced computed tomography in Korea: a multi-institutional study in 101487 patients.

OBJECTIVE: To evaluate the prevalence of known risk factors for contrast-induced nephropathy (CIN) and their association with the actual occurrence of CIN in patients undergoing intravenous contrast-enhanced computed tomography (CECT) in Korea. MATERIALS AND METHODS: Patients who underwent CECT in 2008 were identified in the electronic medical records of 16 tertiary hospitals of Korea. Data on demographics, comorbidities, prescriptions and laboratory test results of patients were collected following a standard data extraction protocol. The baseline renal function was assessed using the estimated glomerular filtration rate (eGFR). We identified the prevalence of risk factors along the eGFR strata and evaluated their influence on the incidence of CIN, defined as a 0.5 mg/dL or 25% increase in serum creatinine after CECT. RESULTS: Of 432425 CECT examinations in 272136 patients, 140838 examinations in 101487 patients met the eligibility criteria for analysis. The mean age of the participants was 57.9 ± 15.5 years; 25.1% of the patients were older than 70 years. The prevalence of diabetes mellitus was 11.9%, of hypertension 13.7%, of gout 0.55% and of heart failure was 1.7%. Preventive measures were used in 40238 CECT examinations (28.6%). The prevalence of risk factors and use of preventive measures increased as the renal function became worse. A CIN was occurred after 3103 (2.2%) CECT examinations, revealing a significant association with decreased eGFR, diabetes mellitus, and congestive heart failure after adjustment. CONCLUSION: Risk factors for CIN are prevalent among the patients undergoing CECT. Preventive measures were seemingly underutilized and a system is needed to improve preventive care.

Computed tomography and magnetic resonance images of adrenocortical oncocytoma cases.

We present two cases of adrenocortical oncocytomas that were well-delineated on multi-detector computed tomography and magnetic resonance imaging. The images showed a well-enhanced large mass with multiple stippled calcifications in a 10-yr-old girl who was consulted due to precocious puberty. A well-enhanced solid mass with necrotic components was incidentally noticed in a 54-yr-old man. These lesions were resected and diagnosed as adrenocortical oncocytomas through immunohistochemical studies and electron microscopy. Adrenocortical oncocytomas are rare disease entities, therefore, we report these interesting, rare adrenocortical oncocytomas here with radiologic findings, and discuss differential diagnosis.

Focal thickening at the fundus of the gallbladder: computed tomography differentiation of fundal type adenomyomatosis and localized chronic cholecystitis.

BACKGROUND/AIMS: The objective of our study was to identify useful computed tomography (CT) findings for differentiating fundal type adenomyomatosis from localized chronic cholecystitis involving the fundus of the gallbladder. METHODS: We retrospectively identified cases of 41 patients with pathologically proven adenomyomatosis (n=21) or chronic cholecystitis (n=20) who had fundal thickening of the gallbladder on preoperative abdominal CT. Analysis of the CT findings included evaluation of the thickness, contour, border, intralesional cystic area, adjacent gallbladder wall thickening, presence of inner layer enhancement, enhancement grade, enhancement pattern, and presence of stones. Statistical analyses were performed using the Mann-Whitney U test and Fisher exact test. RESULTS: Oval contour, inner layer enhancement and intralesional cystic area were more frequently noted in adenomyomatosis than in chronic cholecystitis (p<0.05 for each finding). Flat contour and adjacent gallbladder wall thickening were more frequently observed in chronic cholecystitis than in adenomyomatosis. No differences between adenomyomatosis and chronic cholecystitis in terms of the thickness, enhancement grade, enhancement pattern and presence of stones were apparent. CONCLUSIONS: CT may help to differentiate fundal type adenomyomatosis from localized chronic cholecystitis involving the fundus of the gallbladder.

Epididymal lymphoma: report of two cases and imaging findings.

Epididymal lymphoma is a very rare tumor that is difficult to differentiate radiologically from other paratesticular tumors. Most cases of epididymal lymphoma are secondary involvement of the epididymis in patients with testicular lymphoma. However, isolated epididymal lymphoma is very rare. We herein report two cases of isolated epididymal lymphoma with different imaging findings. Patient 1 was a 52-year-old man who presented with a painless scrotal mass. Patient 2 was a 65-year-old man who presented with painless scrotal swelling. Ultrasound (US) demonstrated different imaging findings: US in patient 1 showed a well-defined round mass in the tail of the epididymis with hypervascularity confined to the epididymis, while US in patient 2 showed diffuse infiltrative enlargement with hypervascularity confined to the epididymis. Orchiectomy performed in both patients revealed diffuse large B-cell lymphoma confined to the epididymis.

Application of 31P MR spectroscopy to the brain tumors.

OBJECTIVE: To evaluate the clinical feasibility and obtain useful parameters of (31)P magnetic resonance spectroscopy (MRS) study for making the differential diagnosis of brain tumors. MATERIALS AND METHODS: Twenty-eight patients with brain tumorous lesions (22 cases of brain tumor and 6 cases of abscess) and 11 normal volunteers were included. The patients were classified into the astrocytoma group, lymphoma group, metastasis group and the abscess group. We obtained the intracellular pH and the metabolite ratios of phosphomonoesters/phosophodiesters (PME/PDE), PME/inorganic phosphate (Pi), PDE/Pi, PME/adenosine triphosphate (ATP), PDE/ATP, PME/phosphocreatine (PCr), PDE/PCr, PCr/ATP, PCr/Pi, and ATP/Pi, and evaluated the statistical significances. RESULTS: The brain tumors had a tendency of alkalization (pH = 7.28 ± 0.27, p = 0.090), especially the pH of the lymphoma was significantly increased (pH = 7.45 ± 0.32, p = 0.013). The brain tumor group showed increased PME/PDE ratio compared with that in the normal control group (p = 0.012). The ratios of PME/PDE, PDE/Pi, PME/PCr and PDE/PCr showed statistically significant differences between each brain lesion groups (p < 0.05). The astrocytoma showed an increased PME/PDE and PME/PCr ratio. The ratios of PDE/Pi, PME/PCr, and PDE/PCr in lymphoma group were lower than those in the control group and astrocytoma group. The metastasis group showed an increased PME/PDE ratio, compared with that in the normal control group. CONCLUSION: We have obtained the clinically applicable (31)P MRS, and the pH, PME/PDE, PDE/Pi, PME/PCr, and PDE/PCr ratios are helpful for differentiating among the different types of brain tumors.

Actinomycosis of the appendix mimicking appendiceal tumor: a case report.

Actinomycosis is an uncommon chronic infectious disease. Common sites of involvement include the cervicofacial, thoracic and abdominopelvic regions. In abdominopelvic actinomycosis, the ileocecal region, including the appendix, is the most commonly involved site. In some reports, limited appendiceal actinomycosis has revealed a thickened appendiceal wall with peri-appendiceal inflammation as acute appendicitis or perforated appendicitis. We experienced pathologically confirmed intraluminal limited appendiceal actinomycosis without peri-appendiceal infiltration. Here, we report the computed tomography and ultrasound findings.

Vascular calcification score on plain radiographs of the feet as a predictor of peripheral arterial disease in patients with chronic kidney disease.

BACKGROUND: The incidence of lower extremity amputation is increasing in patients with chronic kidney disease (CKD), but symptoms of peripheral arterial disease (PAD) in patients with CKD are uncommon. The aim of the current study was to assess the value of the vascular calcification (VC) score on plain radiographs of the feet for the prediction of PAD in patients with CKD. METHODS: We recruited 102 patients with CKD (24 pre-dialysis, 58 hemodialysis [HD], and 20 peritoneal dialysis [PD]). We defined the VC score on the plain radiographs of the feet as follows: score 0, no calcification; score 1, the length of the VC is <5 cm in a single foot or <2 cm in both feet; and score 2, the length of the VC is >5 cm in a single foot or >2 cm in both feet. We evaluated the atherosclerotic calcified plaques of the femoral or popliteal artery with Doppler ultrasonography and compared it with the VC score. RESULTS: Patients with high VC scores showed more atherosclerotic calcified plaques in the femoral or popliteal artery (P < 0.01). The prevalence of PAD in patients with CKD was closely related with the VC score (P < 0.01). PAD was associated with diabetes, a higher hsCRP, and a lower total cholesterol level (P < 0.01). The VC score was a significant predictor of the presence of PAD (odds ratio: 6.66, P < 0.001). CONCLUSIONS: Asymptomatic CKD patients, including those on HD and PD, may have PAD and routine testing by plain radiographs of the feet followed by Doppler ultrasonography are of pivotal significance, especially if the patients are diabetic.

Radiofrequency ablation of renal VX2 tumors with and without renal artery occlusion in a rabbit model: feasibility, therapeutic efficacy, and safety.

The purpose of this study was to determine the therapeutic efficacy of radiofrequency ablation for treating renal VX2 tumors with and without renal artery occlusion in a rabbit model. Twenty-four New Zealand White rabbits were percutaneously implanted with renal VX2 tumors. Fifteen days after implantation, both kidneys were surgically exposed, and radiofrequency ablation was conducted. Group A (n=12) was treated with renal artery occlusion, and group B (n=12) was treated without occlusion. In each rabbit, the serum creatinine was measured to evaluate renal damage after arterial occlusion. Two days after radiofrequency ablation, computed tomography was performed to evaluate the difference in therapeutic results between the two groups. We also compared histopathologic findings after radiofrequency ablation. The mean tumor size was 2.4 cm (range, 1.2-3.1 cm). Radiofrequency ablation of renal tumors was technically feasible in all cases. Complete ablation was achieved in 11 of the 12 rabbits (92%) in group A but in only eight of the 12 rabbits (67%) in group B (P<0.05). The average time of radiofrequency application was shorter in group A (mean, 547 s) than in group B (mean, 826 s) (P<0.05). After radiofrequency ablation, the serum creatinine increased from 1.54 to 1.82 mg/dl in group A and from 1.46 to 1.78 mg/dl in group B. However, there was no significant difference between the two groups (P>0.05). In conclusion, radiofrequency ablation with renal artery occlusion can decrease the duration of treatment and increase the therapeutic efficacy for renal VX2 tumors.

Radiofrequency ablation treatment for renal cell carcinoma: early clinical experience.

OBJECTIVE: To evaluate the early clinical experience associated with radiofrequency (RF) ablation in patients with renal cell carcinoma (RCC). MATERIALS AND METHODS: The RF ablation treatment was performed on 17 tumors from 16 patients (mean age, 60.5 years; range, 43-73 years) with RCC. The treatment indications were localized, solid renal mass, comorbidities, high operation risk, and refusal to perform surgery. All tumors were treated by a percutaneous CT (n = 10), followed by an US-guided (n = 2), laparoscopy-assisted US (n = 2), and an open (n = 2) RF ablation. Furthermore, patients underwent a follow-up CT at one day, one week, one month, three and six months, and then every six months from the onset of treatment. We evaluated the technical success, technical effectiveness, ablation zone, benign periablation enhancement, irregular peripheral enhancement, and complications. RESULTS: All 17 exophytic tumors (mean size, 2.2 cm; range, 1.1-5.0 cm) were completely ablated. Technical success and effectiveness was achieved in all cases and the mean follow-up period was 23.8 months (range, 17-33 months). A local recurrence was not detected in any of the cases; however, five patients developed complications as a result of treatment, including hematuria (n = 2), mild thermal injury of the psoas muscle (n = 1), mild hydronephrosis (n = 1), and fistula formation (n = 1). CONCLUSION: The RF ablation is an alternative treatment for exophytic RCCs and represents a promising treatment for some patients with small RCCs.

Benign submucosal lesions of the stomach and duodenum: imaging characteristics with endoscopic and pathologic correlation.

Benign submucosal lesions of the stomach and duodenum are occasionally encountered during endoscopy. But endoscopy has its limitations in the diagnosis and differentiation of these lesions, because submucosal lesions are often difficult to visualize at endoscopy due to minimal change of the overlying mucosa. Furthermore, endoscopic biopsy may not always yield adequate tissue for diagnosis due to the submucosal location of the lesions. For this reason, the role of radiologic imaging is important in the diagnosis of submucosal lesions of the stomach and duodenum. Recent advances in computed tomography (CT) and sonographic technology are helpful in narrowing the differential diagnosis of gastroduodenal submucosal lesions. In contrast to endoscopy and barium studies, CT or ultrasonography (US) provides information about both the gastric wall and the extragastric extent of the disease. Arterial phase contrast enhanced CT enables us to discriminate a mass of submucosal from that of a mucosal origin in the differential diagnosis of gastric or duodenal lesions. Although endoscopic sonography has been considered the better modality in the diagnosis of gastroduodenal submucosal lesions, transabdominal sonography can still be an alternative method to endoscopic sonography in assessing of the origin and character of the submucosal lesions. Some gastroduodenal submucosal lesions have similar radiologic findings that make differentiation difficult. But despite overlaps in radiologic findings, some lesions have characteristic radiologic features that may suggest a specific diagnosis. Knowledge of the differential diagnosis of benign submucosal lesions in the stomach and duodenum may promote correct diagnosis and appropriate treatment.

Collecting duct carcinoma of the kidney: CT and pathologic correlation.

PURPOSE: We characterized CT findings of collecting duct carcinoma of the kidney and correlated these with the histopathologic findings. MATERIALS AND METHODS: CT scans of 18 patients with pathologically proven collecting duct carcinoma of the kidney were retrospectively reviewed. We analyzed CT findings of collecting duct carcinoma and also correlated CT findings with the histopathologic findings. RESULTS: The mean size of the tumors was 6.9 cm and all cases were solid. Seventeen (94%) tumors had a medullary location. Nine (69%) and 11 (85%) cases showed weak and heterogeneous enhancement, respectively. A cystic component (50%) was frequently seen within the tumors. Lymphadenopathy and metastasis were noted in 10 (56%) and 6 (33%) cases, respectively. Perinephric stranding and vascular invasion were present in 10 (56%) and 5 (28%) cases, respectively. In 17 (94%) of the 18 cases, involvement of the renal sinus was present. Infiltrative growth (67%) and preservation of the renal contour (61%) were more common than expansile growth (33%) and exophytic configuration (39%), respectively. These CT features were well correlated with the histopathologic findings. CONCLUSION: Medullary location, weak and heterogeneous enhancement, involvement of the renal sinus, infiltrative growth, preserved renal contour, and a cystic component are CT findings frequently seen in patients with collecting duct carcinoma of the kidney. CT findings are nevertheless nonspecific and do not allow collecting duct carcinoma to be easily differentiated from the other subtypes of renal cell carcinoma. However, when CT demonstrates a renal tumor with these findings, collecting duct carcinoma can be considered in the differential diagnosis.

Perfusion imaging of the brain using Z-score and dynamic images obtained by subtracting images from before and after contrast injection.

OBJECTIVE: The aim of this study was to examine the feasibility of perfusion imaging of the brain using the Z-score and subtraction dynamic images obtained from susceptibility contrast MR images. MATERIALS AND METHODS: Five patients, each with a normal MRI, Moya-moya, a middle cerebral artery occlusion, post-trauma syndrome, and a metastatic brain tumor, were selected for a presentation. A susceptibility-contrast echo-planar image after a routine MRI was taken as the source image with a rapid manual injection of 0.1 mmol/kg of Gd-DTPA. The inflow and washout patterns were observed from the time-signal intensity curve of the serial scans using the standard program of an MRI machine. The repeated Z-score images of the peak and late phases were made using the threshold Z-score values between 1.4 and 2.0 in four to five studies of the pre-contrast, peak, and late phases. Dynamic subtraction images were produced by subtracting sequential post-contrast images from a pre-contrast image and coloring these images using a pseudocolor mapping method. RESULTS: In the diseases with perfusion abnormalities, the Z-score images revealed information about the degree of perfusion during the peak and late phases. However, the quality varied with the Z-score threshold and the studies selected in a group. The dynamic subtraction images were of sufficient quality with no background noise and more clearly illustrated the temporal changes in perfusion and delayed perfusion. CONCLUSION: The Z-scores and dynamic subtraction images illustrated the degree of perfusion and sequential changes in the pattern of perfusion, respectively. These images can be used as a new complimentary method for observing the perfusion patterns in brain diseases.