Predictive Value of Chemical-Shift MRI in Distinguishing Clear Cell Renal Cell Carcinoma From Non-Clear Cell Renal Cell Carcinoma and Minimal-Fat Angiomyolipoma.

OBJECTIVE: The purpose of this study was to evaluate the diagnostic performance of chemical-shift MRI in the differentiation of clear cell renal cell carcinoma (RCC) from minimal-fat angiomyolipoma (AML) and non-clear cell RCC. MATERIALS AND METHODS: In this retrospective study, 97 patients with solid renal tumors without macroscopic fat and with a pathologic diagnosis of clear cell RCC (n = 40), non-clear cell RCC (n = 31), or minimal-fat AML (n = 26) who had undergone renal chemical-shift MRI were included. Size, location, morphology, and signal intensity (SI) of the tumors and the contralateral normal kidneys on T2-weighted and in-phase and opposed-phase images were recorded by readers blinded to the pathology. Percentage tumor-to-renal parenchymal SI drop (percentage SI drop) was calculated and correlated to tumor histology. The statistical analysis was done using Kruskal-Wallis, one-way ANOVA, chi-square, and Fisher exact tests. RESULTS: The percentage SI drop was significantly higher in clear cell RCC compared with non-clear cell RCC and minimal-fat AML (p < 0.001). Percentage SI drop of greater than 20% had 57.5% sensitivity, 96.5% specificity, and 92% positive predictive value (PPV); and percentage SI drop greater than 29% had 40% sensitivity and 100% specificity for diagnosis of clear cell RCC within the cohort of clear cell RCC, minimal-fat AML, and non-clear cell RCC. A significant proportion of minimal-fat AML (46.2%) displayed homogeneous low T2-weighted SI as opposed to clear cell RCC (5%) and non-clear cell RCC (29%) (p < 0.001). CONCLUSION: The percentage SI drop on chemical-shift MRI had high specificity and moderate sensitivity in predicting clear cell RCC over non-clear cell RCC and minimal-fat AML. A percentage SI drop greater than 20% in a renal mass without macroscopically visible fat has high PPV for clear cell RCC over minimal-fat AML and non-clear cell RCC. Among morphologic features, homogeneous low T2 SI favors minimal-fat AML over RCC.

Bladder reconstruction using scaffold-less autologous smooth muscle cell sheet engineering: early histological outcomes for autoaugmentation cystoplasty.

OBJECTIVE: To investigate the feasibility of a new approach for cystoplasty using autologous smooth muscle cell (SMC) sheet and scaffold-less bladder tissue engineering with the main focus on histological outcomes in a rabbit model. MATERIALS AND METHODS: In all, 24 rabbits were randomly divided into two groups. In the experimental group, SMCs were obtained from the bladder muscular layer, labelled with PKH-26, and seeded on temperature-responsive culture dishes. Contiguous cell sheets were noninvasively harvested by reducing the temperature and triple-layer cell-dense tissues were constructed. After partial detrusorectomy, the engineered tissue was transplanted onto the urothelial diverticulum. The control group underwent partial detrusorectomy followed by peritoneal fat coverage. At 2, 4, and 12 weeks the rabbits were humanely killed and haematoxylin and eosin, Masson's trichrome, cluster of differentiation 34 (CD34), CD31, CD3, CD68, α-smooth muscle actin (α-SMA), picrosirius red, and pentachrome staining were used to evaluate bladder reconstruction. RESULTS: At 2 weeks after SMC-sheet grafting, PKH-26 labelled SMCs were evident in the muscular layer. At 4 weeks, 79.1% of the cells in the muscular layer were PKH-positive cells. The portion of the muscular layer increased in the experimental group during the follow-up and was similar to normal bladder tissue after 12 weeks. α-SMA staining showed well organised muscle at 4 and 12 weeks. CD34+ endothelial progenitor cells and CD31+ microvessels increased continuously and peaked 4 and 12 weeks after grafting, respectively. CONCLUSION: In the present study, we show that autologous SMC-sheet grafting has the potential for reliable bladder reconstruction and is technically feasible with a favourable evolution over the 12 weeks following implantation. Our findings could pave the way toward future bladder tissue engineering using the SMC-sheet technique.

Anal sphincter repair with muscle progenitor cell transplantation: serial assessment with iron oxide-enhanced MRI.

OBJECTIVE: The purpose of this study was to assess homing of ultrasmall superparamagnetic iron oxide (USPIO)-labeled muscle progenitor cells in an experimental rabbit model of anal sphincter repair using MRI. MATERIALS AND METHODS: Twelve rabbits underwent external anal sphincterotomy and randomly received injection of either autologous muscle progenitor cells labeled with USPIO at a concentration of 4 mg/10(6) cells (experimental group) or saline (control group) at the site of sphincter damage. In vivo MRI, electromyography, and manometry were performed before, 1 hour after, and 1, 2, and 4 weeks after the injection. At the end time point, anal sphincter sections were obtained for histologic analysis. Semiquantitative analysis of fibrosis, desmin, iron, CD3, and CD68 was performed using two microscopic fields in two distinct regions of the sphincter according to either presence (zone I) or absence (zone II) of signal loss on the corresponding MR images. RESULTS: Labeling efficiency was 88.67% and did not influence cell viability. On follow-up images of the cell-transplanted rabbits, significant influence was reported at 1 hour, 1 and 2 weeks after transplantation. The maximum signal loss was detected at 1 hour (75.7%). Regenerating myofibers stained positively for desmin and mainly correlated to zone I on MR images. Clusters of iron-positive particles were detectable in the myofibers located mainly at the site of injection, which correlated well to zone I. Significant signal loss and Perls Prussian blue-positive area were not detected in the control group. Functional studies showed significant improvement in sphincter pressure and electrical activity in the experimental group after 4 weeks (p<0.001). CONCLUSION: Our results support the potential of iron oxide-enhanced MRI for serial monitoring of transplanted cells in an animal model of anal sphincter repair.

Cystic renal cell carcinomas: do they grow, metastasize, or recur?

OBJECTIVE: The purpose of this study is to evaluate the interval growth, tumor recurrence, and metastatic disease occurrence of cystic renal cell carcinoma (RCC). MATERIALS AND METHODS: Pre-and posttreatment imaging of 47 histologically proven cystic RCCs, with at least 6 months of pretreatment imaging monitoring or at least 2 years of posttreatment imaging follow-up, or both, was retrospectively reviewed. Tumor morphologic features, preoperative growth, histologic typing and grading, and the incidence of tumor recurrence or metastasis were evaluated. Growth rate of tumors were compared among various histologic subtypes and Fuhrman grades. RESULTS: Of 47 tumors, 27 (57.5%) were clear cell RCCs, 12 (25.5%) were multilocular RCCs, and eight (17%) were papillary cystic RCCs. Overall, 26 (55.3%) tumors were graded as Fuhrman grade 2, 17 (36.1%) were Fuhrman grade 1, and one tumor was Fuhrman grade 3. Of the 26 tumors with a minimum of 6 months of pretreatment imaging monitoring, 19 (73%) did not show a significant increase in tumor size. The differences in mean growth among the Fuhrman grades and different subtypes were not statistically significant. The average duration of posttreatment follow-up was 51 months. There were no local recurrences among the 43 patients who underwent posttreatment imaging, except for one patient who had metastasis at preoperative clinical presentation. CONCLUSION: Cystic RCCs exhibit slow indolent growth, if any, and show no significant metastatic or recurrence potential, with excellent clinical outcomes. We raise the need for revisiting current imaging protocols that may involve frequent pre-and posttreatment imaging in cystic RCCs.

The spectrum of IgG4-related disease in the abdomen and pelvis.

OBJECTIVE: IgG4-related disease was not recognized as a specific clinical entity until 2003 when extrapancreatic lesions were reported in patients with autoimmune pancreatitis. IgG4-related disease is characterized by elevated serum IgG4 levels and infiltration of the target organ by IgG4-positive plasma cells. The complete gamut of visceral involvement is still being outlined. The purpose of this article is to highlight the plethora of lesions under the spectrum of IgG4-related disease of the abdomen and pelvis, describe their imaging appearances on multimodality cross-sectional imaging, and discuss the differential diagnoses. CONCLUSION: It is important for radiologists to recognize the multiorgan involvement and few classic features of IgG4-related disease that often tend to simulate malignancy.

Imaging behavior of the normal adrenal on ferumoxytol-enhanced MRI: preliminary findings.

OBJECTIVE: Ultrasmall superparamagnetic iron oxide nanoparticles, such as ferumoxytol, produce decreased MR signal on susceptibility-inducing T2*-weighted sequences in tissues of the reticuloendothelial system. However, acute iron deposition in the adrenals has not been reported. The purpose of this article is to report our initial observations of the imaging behavior of the normal adrenals on ferumoxytol-enhanced T2*-weighted magnetic resonance imaging. SUBJECTS AND METHODS: Quantitative T2* imaging was performed at 3 T using a breath-hold monopolar multiecho gradient echo sequence with six equally spaced in-phase echoes in nine patients. Changes in signal-to-noise ratio (SNR) were analyzed prior to and 48 hours after ferumoxytol administration in the adrenals, liver and spleen (positive controls), and pancreas and skeletal muscle (negative controls). RESULTS: In comparison with unenhanced images, there was an average SNR decrease of 67.4% in the right adrenal, 77.6% in the left adrenal, 68.4% in the liver, 89.1% in the spleen, 15.0% in the pancreas, and 9.5% in skeletal muscle on T2*-weighted images obtained 48 hours after ferumoxytol administration. The decrease in SNR observed in the adrenals was significantly greater than that seen in the pancreas and skeletal muscle (left adrenal, p < 0.0001; right adrenal, p = 0.0002) and similar to that seen in the liver and spleen. CONCLUSION: The normal adrenal loses signal on ferumoxytol-enhanced T2*-weighted MRI. Acute iron deposition within the adrenals has not been previously described. The mechanism of ferumoxytol uptake in the adrenal and potential clinical applications warrant further investigation.

Is early colonoscopy beneficial in patients with CT-diagnosed diverticulitis?

OBJECTIVE: The purpose of this study was to establish CT criteria as an indication for colonoscopy in patients with acute diverticulitis. MATERIALS AND METHODS: The study was composed of patients diagnosed with acute diverticulitis on contrast-enhanced CT (CECT) from January 2000 to December 2004. Patients without subsequent colonoscopy were excluded. Findings on CT were correlated with patient outcomes over follow-up. Sensitivity, specificity, and predictive values of the imaging parameters for prediction of colon cancer were calculated. Outcomes were also compared between men and women. RESULTS: Of 1034 patients with a CT diagnosis of diverticulitis, 402 (235 women and 167 men; mean age, 63.3 years) had available endoscopic colonic evaluation after CECT. The mean follow-up was 5.3 years. Seventy-eight patients had polyps (71% adenomatous) and nine patients (2.2%) were diagnosed with colon cancer (seven women, two men). The odds ratio for diagnosis of colon cancer was 23.35 in patients with mesenteric or retroperitoneal lymphnodes, 4.67 for abscess, and 24.43 in patients with obstruction and localized mass reported on CT. A significant correlation was found between the location of diverticulitis and cancer (p < 0.001). The diagnosis of cancer was made within 6 months from the date of CECT in eight patients. The odds of cancer were 2.5 times higher in women. CONCLUSION: On the basis of the significant correlation of complicated diverticulitis or presence of lymph nodes with new diagnoses of colon cancer, we recommend early colonoscopy in patients with wall thickness more than 6 mm, abscess, obstruction, or lymph nodes seen on CECT.

Incidental findings at initial imaging workup of patients with prostate cancer: clinical significance and outcomes.

OBJECTIVE: The purpose of this article is to evaluate the frequency and clinical relevance of incidental findings in patients with prostate cancer who underwent abdominopelvic contrast-enhanced CT examination for initial staging workup. MATERIALS AND METHODS: We retrospectively reviewed 355 initial staging abdominopelvic contrast-enhanced CT examinations conducted from January 2000 to December 2010 in patients with prostate cancer for incidental findings that were not related to prostate cancer. A finding was judged to be potentially significant if therapeutic intervention, additional imaging, or tissue sampling was deemed advisable. The rate of incidental findings was correlated to patients' age and stratified prostate cancer risk groups. RESULTS: We found 779 incidental finding in 292 patients (82.3%), of which 75 findings in 73 patients (20.6%) were potentially significant. Indeterminate masses were the most prevalent significant finding (n = 62). Synchronous malignancy was detected in 21 patients (5.9%). Kidney cancer (n = 7 [1.97%]) was the most common malignancy, followed by lymphoma (n = 4 [1.13%]). Staging of the cancers revealed that 15 patients, including all of those with renal cancer, had N0M0 disease. Significant vascular abnormalities were reported in six cases. Additionally, significant findings, synchronous malignancies in particular, were identified at a higher rate in patients older than 65 years. However, no significant differences were noticed between the different prostate cancer risk groups. CONCLUSION: Abdominal contrast-enhanced CT for initial staging of prostate cancer shows a considerable prevalence of incidental vascular events and synchronous cancers, with kidney cancers being the most common. Notably, 71.5% of these malignancies were at early stage. Our results show an incremental value of CT in prostate cancer staging, with an emphasis on focused evaluation of the kidneys.

Safety, efficacy and health related quality of life of autologous myoblast transplantation for treatment of urinary incontinence in children with bladder exstrophy-epispadias complex.

PURPOSE: Children with bladder exstrophy-epispadias complex undergoing endourethral autologous myoblast transplantation to treat urinary incontinence were evaluated at 4 years of followup regarding the safety, efficacy and durability of the procedure, and health related quality of life. MATERIALS AND METHODS: Seven boys underwent autologous myoblast transplantation between May and December 2006. All patients had persistent urinary incontinence after bladder neck reconstruction and bulking agent injection. Patients were followed for 4 years after autologous myoblast transplantation regarding clinical outcomes and cystometric, urodynamic, uroflowmetric and urethrocystoscopic evaluations. Health related quality of life was also measured before treatment and at final followup. RESULTS: No evidence of urinary obstruction was observed. Five children (71%) were completely continent and 2 (29%) were socially dry with complete daytime dryness at final followup. Health related quality of life was improved significantly. Urodynamic studies revealed a progressive increase in bladder capacity (p <0.001). Mean detrusor leak point pressure showed a 27 cm H(2)O (158%) increase during 4-year followup. Uroflowmetry parameters of voided volume and average maximum flow rate were improved significantly (p <0.001). CONCLUSIONS: The 4-year outcomes demonstrate that autologous myoblast transplantation for urinary incontinence in children with bladder exstrophy-epispadias complex is relatively reliable, reproducible, safe and effective with minimal morbidity. This novel treatment represents a promising therapeutic approach in patients with urinary incontinence. Further randomized trials with larger numbers of patients and longer followup are needed.

Single-stage subsymphyseal cystoscopic-guided bladder neck plication and urethrogenitoplasty in female epispadias: presentation of long-term follow-up.

OBJECTIVE: • To investigate the feasibility of an endoscopic technique as a guide to evaluate bladder outlet resistance during bladder neck plication (BNP) for treatment of female epispadias. PATIENTS AND METHODS: • The postoperative outcomes with long-term follow-up of 10 girls with epispadias were reviewed (four had a previous history of bulking agent injection into the BN). • After taking a skin flap from the area between the crura of the bifid clitoris, subsymphyseal dissection was continued to the BN. • Under cystoscopic guidance, BNP was performed using absorbable sutures (two cases) or non-absorbable sutures (eight) aiming to attain a smooth closure of the BN during gradual withdrawal of the cystoscope. • Finally, urethrogenitoplasty was accomplished by urethral reconstruction with tubularization of the inter-clitorial flap followed by monsplasty and approximation of the two hemi-clitorises. RESULTS: • The mean (range) follow-up was 9.1 (5-15) years. • After primary surgery seven of the 10 girls were continent and all could void normally. • Of the three failed cases (including two that underwent BNP using absorbable suture), two became dry after injection of bulking agent into the BN and the remaining girl underwent BN reconstruction; she was socially continent at the final follow-up. • Ultimately, all 10 girls were socially continent, including six who were completely dry. • Urodynamic studies showed an increase in mean bladder capacity (P < 0.001) and a significant time-dependent improvement of the leak-point pressure and maximum urinary flow rate. CONCLUSIONS: • The present series suggests that single-stage subsymphyseal urethrogenitoplasty together with cystoscopic-guided BNP for management of female epispadias is reliable and effective with definite advantages. • The high success rate and safety of the procedure are important factors for the introduction of this method as a valid option for treatment of this rare congenital anomaly.

Precise delineation of ureterocele anatomy: virtual magnetic resonance cystoscopy.

PURPOSE: To evaluate the application of virtual magnetic resonance cystoscopy (VMRC) in precise detection of ureterocele extension compared with conventional cystoscopy (as the gold standard) and other imaging modalities. MATERIALS AND METHODS: Medical records of 55 patients, with confirmed diagnosis of ureterocele during endoscopic surgery, were reviewed retrospectively. Thirty-two of them (14 girls and 18 boys, age range: 4-22 months) whom underwent investigation with magnetic resonance urography, voiding cystourethrography, and ultrasonography were included. Images were obtained using T1-scanner with pulse sequences (TR = 30-50 ms, TE = 2-8 ms, echo train length = 8 moderate, filip angel = 40°). Using multiplanar reformation from source images, the bladder was evaluated to determine ureterocele anatomy. Virtual findings were compared with other imaging studies. RESULTS: Cystoscopy confirmed 3(9%) bilateral and 9(28%) unilateral intravesical ureteroceles, and 20(63%) ectopic type. VMRC was the most sensitive method in detection of ureterocele anatomy and its extension (detection rate: 94%) It detected one case of bilateral intravesical and three ectopic types, which were not detected in other imaging modalities. CONCLUSION: VMRC is a promising non-invasive technique in exact detection of ureterocele extension prior to endoscopic operation. It permits evaluation of concurrent genitourinary abnormalities and facilitates preoperative planning especially in complex ectopic ureteroceles. It may be indicated as a clinical routine, when conventional cystoscopy is contraindicated.

Preoperative breast MR imaging in newly diagnosed breast cancer: Comparison of outcomes based on mammographic modality, breast density and breast parenchymal enhancement.

PURPOSE: To compare the role of MR for assessment of extent of disease in women newly diagnosed with breast cancer imaged with digital mammography (DM) alone versus digital breast tomosynthesis (DBT). METHODS: Retrospective review was conducted of 401 consecutive breast MR exams (10/1/2013-7/31/2015) from women who underwent preoperative MR for newly diagnosed breast cancer by either DM or DBT, leaving 388 exams (201 DM and 187 DBT). MR detection of additional, otherwise occult, disease was stratified by modality, breast density, and background parenchymal enhancement. A true-positive finding was defined as malignancy in the ipsilateral-breast >2 cm away from the index-lesion or in the contralateral breast. RESULTS: 50 additional malignancies were detected in 388 exams (12.9%), 37 ipsilateral and 13 contralateral. There was no difference in the MR detection of additional disease in women imaged by either DM versus DBT (p = 0.53). In patients with DM, there was no significant difference in the rate of MR additional cancer detection in dense versus non-dense breasts (p = 0.790). However, in patients with DBT, MR detected significantly more additional sites of malignancy in dense compared to non-dense breasts (p = 0.017). There was no difference in false-positive MR exams (p = 0.470) for DM versus DBT. For both DM and DBT cohorts, higher MR background parenchymal enhancement was associated with higher false-positive (p = 0.040) but no significant difference in true-positive exams. CONCLUSIONS: Among patients with DBT imaging at cancer diagnosis, women with dense breasts appear to benefit more from preoperative MR than non-dense women. In women imaged only with DM, MR finds additional malignancy across all breast densities.

Urinary and serum carbohydrate antigen 19-9 as a biomarker in ureteropelvic junction obstruction in children.

PURPOSE: We evaluated the predictive role of serum and urinary carbohydrate antigen 19-9 in the diagnosis and followup of pediatric ureteropelvic junction obstruction. MATERIALS AND METHODS: The study included 27 children with ureteropelvic junction obstruction who underwent pyeloplasty (group 1), and 41 controls consisting of 27 healthy children (group 2) and 14 children with hydrocele/renal cyst (group 3). Serum and voided urine were evaluated for carbohydrate antigen 19-9 in each group. Additionally urine from the affected pelvis and fluid in hydrocele/renal cyst were collected at surgery in groups 1 and 3. Serum and voided urine samples were obtained at 3, 6 and 9 months after pyeloplasty for carbohydrate antigen 19-9 assessment, and were correlated with clinical factors. RESULTS: Preoperative carbohydrate antigen 19-9 level was significantly greater in group 1 than in controls. The best cutoff values for serum and urinary carbohydrate antigen 19-9 were 13.21 U/ml and 30.6 U/ml, respectively, with significantly higher sensitivity and specificity for urinary values. Obstruction release was followed by improvement of renal function together with significant reduction in urinary and serum carbohydrate antigen 19-9 at 3 months. Initial pelvis diameter and renographic function significantly correlated with urinary carbohydrate antigen 19-9. No significant correlation was found regarding serum carbohydrate antigen 19-9. CONCLUSIONS: Voided urine carbohydrate antigen 19-9 is a noninvasive, clinically applicable marker in congenital obstructive nephropathy. The practical implications of these data for diagnosis and long-term followup in ureteropelvic junction obstruction are significant. Our findings suggest that proper decrease in urinary carbohydrate antigen 19-9 after pyeloplasty is predictive of excellent surgical outcomes and resolution of renal damage.

Genitourinary involvement in epidermolysis bullosa: clinical presentations and therapeutic challenges.

OBJECTIVES: To present our experience of children with epidermolysis bullosa (EB; a rare bullous disorder of the skin) with genitourinary involvement. PATIENTS AND METHODS: The medical records of eight children diagnosed with EB (six junctional and two dystrophic type) with genitourinary involvement were reviewed retrospectively. The data collected included age, clinical presentation, ultrasonographic findings, voiding cystourethrography, urodynamic and uroflowmetry studies, and the treatment challenges. The outcomes of the interventions were evaluated every 6 months. RESULTS: The mean age was 2.3 years (range 1 day to 7 years). The most common clinical presentations were urinary retention and voiding difficulty. Meatomy was performed in two of three boys followed by diminution of urological complaints. In children with vesico-ureteric reflux, subureteric injections of bulking agent and ureteric stenting were satisfactory. Detrusor instability and bladder compliance improved after α-blocker therapy. The mean (range) follow-up was 62.6 (11-120) months except for two who died in early infancy. CONCLUSIONS: Considering the potential urological involvement in every child with EB it is essential to provide patients with early appropriate treatment. Management of urological problems should preferably be in a way to entail minimal interventions and if required be performed using small sized instruments. Medical therapy seems promising for voiding dysfunction in this subset of patients.

Functional external anal sphincter reconstruction for treatment of anal incontinence using muscle progenitor cell auto grafting.

PURPOSE: This study aimed to investigate the feasibility of autologous muscle progenitor cell transplantation for anal sphincter regeneration in a rabbit model of anal incontinence. We examined the serial changes in structure, with particular emphasis on histology and functional properties of the anal sphincter. METHODS: External anal sphincterotomy was performed in 21 rabbits; these rabbits were randomly assigned to 2 groups. In group I (n = 9), autologous muscle progenitor cells were isolated from quadriceps myofiber explants, labeled with PKH-26, and injected into sphincter 3 weeks after sphincterotomy. In group II (n = 12), saline buffer was injected at the site of damage. Sphincter electromyography and manometry were performed immediately before sphincterotomy and 14, 28, and 60 days after injection in 3 animals in each group at every interval and the findings were correlated with histomorphological studies. In addition, electromyography and manometry were performed in the remaining 3 rabbits in group II after 6 months. RESULTS: In group II, a flaccid sphincter persisted during the 6 months of follow-up. In group I, muscle progenitor autografting accelerated sphincter myofiber repair and improvement in functional capacity of the damaged sphincter. Fluorescently labeled cells were detected in all of the grafted sphincters; regenerated myotubes were detectable at the injection site as evidenced by the presence of desmin. We also observed a significant decrease in interstitial fibrosis in the 4th week and strikingly higher amounts of Ki-67-positive cells in group I. Manometry and electromyography showed a significant improvement in the mean resting anal canal pressure and sphincteric electrical activity 4 weeks after cell injection, respectively. CONCLUSION: Transplanting muscle progenitor cells showed the potential for recapitulation of a myogenic program when injected into deficient rabbit anal sphincter. Objective anal measures of resting and stimulated pressures and electromyographic profile improved. Stem cell-mediated anal myoplasty warrants additional investigation as a new method to treat anal incontinence before attempting this modality in the clinical setting.

Rare Cancer on the Rise: An Educational Review of Breast Implant-associated Anaplastic Large Cell Lymphoma.

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare but increasingly important diagnosis as the incidence of breast implant placement, both elective and reconstructive, continues to rise. When detected and treated early, this indolent disease carries an excellent prognosis. However, because the clinical presentation is often nonspecific, it is crucial for radiologists to accurately identify the imaging findings associated with BIA-ALCL to facilitate a timely diagnosis. This article will provide radiologists with an overview of the diagnosis, imaging findings, and management of BIA-ALCL.

Cell-Proliferation Imaging for Monitoring Response to CDK4/6 Inhibition Combined with Endocrine-Therapy in Breast Cancer: Comparison of [18F]FLT and [18F]ISO-1 PET/CT.

PURPOSE: Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors in combination with endocrine-therapy have emerged as an important regimen of care for estrogen receptor (ER)-positive metastatic breast cancer, although identifying predictive biomarkers remains a challenge. We assessed the ability of two PET-proliferation tracers, [18F]FLT and [18F]ISO-1, for evaluating response to CDK4/6-inhibitor (palbociclib) and ER-antagonist (fulvestrant). EXPERIMENTAL DESIGN: To determine the effect of CDK4/6 inhibition combined with estrogen-blockade, we assessed cell proliferation in six breast cancer cell lines after 1, 3, and 6 days of treatment with palbociclib and/or fulvestrant. These data were correlated to in vitro radiotracer assays and results were verified by longitudinal [18F]FLT and [18F]ISO-1 micro-PET imaging performed in MCF7 tumor-bearing mice. RESULTS: All palbociclib-sensitive cell lines showed decreased [18F]FLT accumulation and S-phase depletion after treatment, with both measures augmented by combination therapy. In contrast, these cells showed changes in [18F]ISO-1 analogue-binding and G0 arrest only after prolonged treatment. MicroPET imaging of MCF7 xenografts showed a significant decrease in [18F]FLT but no changes in [18F]ISO-1 uptake in all treated mice on day 3. On day 14, however, mice treated with combination therapy showed a significant decrease in [18F]ISO-1, corresponding to G0 arrest, while maintaining reduced [18F]FLT uptake, which corresponded to S-phase depletion. CONCLUSIONS: Our data suggest complementary roles of [18F]FLT and [18F]ISO-1 PET in evaluating tumor-proliferation after combined CDK4/6 inhibitor and endocrine therapy in breast cancer. [18F]FLT is more sensitive to immediate changes in S-phase, whereas [18F]ISO-1 can assess more delayed changes related to cell-cycle arrest and transition to G0 quiescence from combination therapy. These data suggest a potential role for early prediction of long-term response using these imaging biomarkers.

Transurethral autologous myoblast injection for treatment of urinary incontinence in children with classic bladder exstrophy.

PURPOSE: The application of autologous myoblasts is an area of active research that may represent an improved alternative for the treatment of urinary incontinence. In this study we investigated the effectiveness of autologous myoblast injection for the treatment of urinary incontinence in children with classic bladder exstrophy. MATERIALS AND METHODS: Seven boys and 1 girl with persistent urinary incontinence were entered in the study. All children had undergone staged bladder repair and bladder neck reconstruction, and 5 patients had received 1 to 3 transurethral injections of bulking agent. Autologous myoblasts were isolated from abdominal muscle biopsy and cultured before endourethral injection. After the procedure patients underwent pelvic floor electrical stimulation and continued pelvic floor exercises that had been started at least 1 year before injection. The clinical outcomes (based on a 24-hour voiding diary), and cystometric and urodynamic studies were evaluated. Followup ranged from 12 to 18 months (average 15.3). RESULTS: There was a significant, time dependent improvement in urinary continence. At final followup all 7 boys (88% of patients) were socially dry (daytime dryness more than 3 hours), including 3 (38%) who were completely dry. Urodynamic studies revealed an increase in mean bladder capacity (p <0.001), detrusor leak point pressure (p <0.001) and average maximum urinary flow (p <0.01). All 7 boys (vs only 2 patients preoperatively) achieved normal voiding with demonstrable voiding detrusor contraction in the presence of a compliant stable bladder (p <0.05). CONCLUSIONS: Our results suggest that transurethral autologous myoblast injection is a valid option for the treatment of structural urinary incontinence in children with classic bladder exstrophy. However, favorable preoperative urodynamic profiles and postoperative pelvic floor electrical stimulation may have contributed to the outcome in this series.

Imaging Tumor Proliferation in Breast Cancer: Current Update on Predictive Imaging Biomarkers.

Uncontrolled growth is a hallmark of cancer; imaging cell proliferation can provides an early indicator of therapeutic response. This capability is especially well-matched to the emerging cell cycle-specific chemotherapeutics with the goal of identifying patients that benefit from these treatments early in the course of treatment to guide personalized therapy. This article focuses on investigational cell proliferation imaging PET radiotracers to evaluate tumor proliferation in the setting of cell cycle-targeted chemotherapy and endocrine therapy for metastatic breast cancer.

Comparison of different techniques for hemostasis in a rabbit model of hypospadias repair.

PURPOSE: We compared the cellular and ultrastructural changes in the urethral wall following application of different hemostasis techniques in a rabbit model of hypospadias surgery. MATERIALS AND METHODS: Rabbits were allocated into 5 groups. In group 1 animals underwent surgery without application of any hemostasis technique; in group 2 continuous penile tourniquet was applied for 30 minutes; in group 3, 3 intermittent periods of 10-minute penile tourniquet were applied with 3-minute intervals of reperfusion; in group 4 epinephrine was injected to maintain a 30-minute period of hemostasis; and in group 5 epinephrine vehicle (normal saline) was injected during the procedure. Early urothelium ultrastructural damage was studied 1 hour postoperatively with electron microscopy. Apoptotic damage and histopathological changes were determined 48 hours following the procedure. Late onset complications were assessed with retrograde urethrography and evaluation of tissue fibrosis at 8 weeks postoperatively. RESULTS: Electron microscope studies demonstrated urothelium ultrastructural damage in all hemostasis groups compared to controls. However, the changes were most prominent in group 4. The apoptosis index of urethral wall myocytes in groups 1 and 5 was significantly lower compared to other groups. Moreover, the number of apoptotic myocytes in epinephrine injected animals was significantly higher than in the continuous or intermittent tourniquet group as well as the normal saline injected group. At 8 weeks postoperatively collagen deposition in the urethral wall of rabbits in group 4 was higher than that in group 1. Although urethrocutaneous fistula was found in only 1 rabbit in group 4, the difference was not significant. CONCLUSIONS: Hemostasis techniques applied for maintaining a bloodless surgical field during hypospadias repair may lead to ischemia/reperfusion tissue damage in the urethral wall. Our findings suggest that epinephrine injection may result in more prominent cellular changes compared to tourniquet techniques. However, further experimental and human studies are required to draw a firm conclusion.