False-Positive and False-Negative Contrast-enhanced Mammograms: Pitfalls and Strategies to Improve Cancer Detection.

Contrast-enhanced mammography (CEM) is a relatively new breast imaging modality that uses intravenous contrast material to increase detection of breast cancer. CEM combines the structural information of conventional mammography with the functional information of tumor neovascularity. Initial studies have demonstrated that CEM and MRI perform with similar accuracies, with CEM having a slightly higher specificity (fewer false positives), although larger studies are needed. There are various reasons for false positives and false negatives at CEM. False positives at CEM can be caused by benign lesions with vascularity, including benign tumors, infection or inflammation, benign lesions in the skin, and imaging artifacts. False negatives at CEM can be attributed to incomplete or inadequate visualization of lesions, marked background parenchymal enhancement (BPE) obscuring cancer, lack of lesion contrast enhancement due to technical issues or less-vascular cancers, artifacts, and errors of lesion perception or characterization. When possible, real-time interpretation of CEM studies is ideal. If additional views are necessary, they may be obtained while contrast material is still in the breast parenchyma. Until recently, a limitation of CEM was the lack of CEM-guided biopsy capability. However, in 2020, the U.S. Food and Drug Administration cleared two devices to support CEM-guided biopsy using a stereotactic biopsy technique. The authors review various causes of false-positive and false-negative contrast-enhanced mammograms and discuss strategies to reduce these diagnostic errors to improve cancer detection while mitigating unnecessary additional imaging and procedures. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Imaging Characteristics of and Multidisciplinary Management Considerations for Atypical Ductal Hyperplasia and Flat Epithelial Atypia: Review of Current Literature.

High-risk lesions of the breast are frequently encountered in percutaneous biopsy specimens. While benign, these lesions have historically undergone surgical excision due to their potential to be upgraded to malignancy. However, there is emerging evidence that a tailored management approach should be considered to reduce overtreatment of these lesions. Flat epithelial atypia (FEA) and atypical ductal hyperplasia (ADH) are two of the most commonly encountered high-risk lesions. FEA has been shown to have a relatively low rate of progression to malignancy, and some guidelines are now recommending observation over routine excision in select cases. Selective observation may be reasonable in cases where the target lesion is small and completely removed at biopsy and when there are no underlying risk factors, such as a history of breast cancer or genetic mutation or concurrent ADH. ADH has the highest potential upgrade rate to malignancy of all the high-risk lesions. Most society guidelines continue to recommend surgical excision of this lesion. More recently, some literature suggests that ADH lesions that appear completely removed at biopsy, involve limited foci (less than two or three) with no necrosis or significant atypia, manifest as a small group of mammographic calcifications, or demonstrate no enhancement at MRI may be reasonable for observation. Ultimately, management of all high-risk lesions must be based on a multidisciplinary approach that considers all patient, radiologic, clinical, and histopathologic factors. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Effect of intracorporeal urinary diversion on the incidence of benign ureteroenteric stricture after cystectomy.

OBJECTIVES: To compare ureteroenteric stricture rates after radical cystectomy in patients who undergo an intracorporeal urinary diversion versus other surgical approaches. METHODS: We retrospectively reviewed health records of all patients who underwent cystectomy with urinary diversion at Mayo Clinic Hospital (Phoenix, AZ, USA) from 1 January 2007 through 1 January 2018. Ureteroenteric stricture was identified by surveillance imaging. Patients were stratified by surgical approach: open radical cystectomy, robot-assisted radical cystectomy with extracorporeal urinary diversion and robot-assisted radical cystectomy-intracorporeal urinary diversion. A Cox proportional hazards model was fitted that included independent predictors of stricture development. RESULTS: Of the 573 cystectomies assessed, 236 (41.2%) were carried out robotically. In the robot-assisted radical cystectomy cohort, 39 patients (16.5%) underwent intracorporeal urinary diversion. The median follow-up period was 55, 70 and 71 months for the open radical cystectomy, robot-assisted radical cystectomy-extracorporeal urinary diversion and robot-assisted radical cystectomy-intracorporeal urinary diversion groups, respectively. Subgroup stricture rates were as follows: open radical cystectomy, 8.0%; robot-assisted radical cystectomy-extracorporeal urinary diversion, 9.6%; and robot-assisted radical cystectomy-intracorporeal urinary diversion, 2.6% (P = 0.33). The median time to stricture was 5 months (interquartile range 3.3-11.5 months). In the bivariable analysis, factors that were associated with the development of ureteroenteric stricture were postoperative urinary leak (hazard ratio 3.177, 95% confidence interval 1.129-8.935; P = 0.03) and body mass index (hazard ratio 1.078, 95% confidence interval 1.027-1.132; P = 0.002). On multivariable logistic regression analysis, intracorporeal urinary diversion approach was not associated with the development of ureteroenteric stricture (hazard ratio 0.272, 95% confidence interval 0.036-2.066; P = 0.21). CONCLUSIONS: Ureteroenteric stricture is a complication that typically occurs within the first postoperative year. Although our results did not support major differences in outcomes between intracorporeal urinary diversion and extracorporeal urinary diversion, the small sample size did not exclude the possibility of a type 2 statistical error.

Use of treatment pathway improves neoadjuvant chemotherapy use in muscle-invasive bladder cancer.

PURPOSE: To assess the trends of neoadjuvant chemotherapy (NAC) use since its introduction in our practice pathway in patients with cT2 + bladder cancer over a 20-year period. METHODS: This is a retrospective review of patients with cT2 + bladder cancer who underwent RC between 01/01/1998 and 01/01/2018 that aimed to evaluate the trends of NAC use and associated after implementation of a multidisciplinary treatment pathway. Cohorts were stratified into eras: pre-NAC (1998-2007) to NAC eras (2008-2018). Univariate analysis was conducted using Chi-squared test and Kaplan-Meier estimates were used to evaluate survival. RESULTS: In 904 total patients who underwent RC, there were 493 with cT2 + UCC disease. The rate of NAC peaked at 84.2% in the most recent year of analysis in all patients and was 100% in cT2 + patients eligible for NAC. There was an increased rate of complete response (downstage to pT0) from 8.7% to 15.8% (p = 0.018) between the two eras. Unadjusted survival analysis revealed improved overall survival (OS) between eras with 5-year OS 53.2% vs. 42.7% and 10-year OS 42.7% vs. 26.4% in the NAC vs. pre-NAC cohorts, respectively (p = 0.016). CONCLUSIONS: In this review of 20 years of experience, we report a dramatic rise in the use of NAC after adoption of a multidisciplinary pathway that is associated with expected survival benefits.

The effect of urinary diversion on long-term kidney function after cystectomy.

OBJECTIVES: Cystectomy with urinary diversion is associated with decreased long-term kidney function due to several factors. One factor that has been debated is the type of urinary diversion used: ileal conduit (IC) vs. neobladder (NB). We tested the hypothesis that long-term kidney function will not vary by type of urinary diversion. METHODS AND MATERIALS: We retrospectively identified all patients who underwent cystectomy with urinary diversion at our institution from January 1, 2007, to January 1, 2018. Data were collected on patient demographics, comorbid conditions, perioperative radiotherapy, and complications. Creatinine values were measured at several time points up to 120 months after surgery. Glomerular filtration rate (GFR) (ml/min per 1.73 m2) was calculated using the Chronic Kidney Disease Epidemiology Collaboration equation. A linear mixed model with inverse probability of treatment weighting (IPTW) was used to compare GFR between the IC and NB cohorts over time. Multiple sensitivity analyses were performed based on 2 different calculations of GFR (Chronic Kidney Disease Epidemiology Collaboration equation vs. Modification of Diet in Renal Disease), with and without excluding patients with preoperative GFR less than 40 ml/min per 1.73 m2. RESULTS: Among 563 patients who underwent cystectomy with urinary diversion, a NB was used for 72 (12.8%) individuals. Patients who had a NB were significantly younger, had a lower American Society of Anesthesiologists score, greater baseline GFR, better Eastern Cooperative Oncology Group performance status, lower median Charlson comorbidity index, and were less likely to have received preoperative abdominal radiation (all P < 0.05). Both NB and IC patients had decreased kidney function over time, with mean GFR losses at 5 years of 17% and 14% of baseline values, respectively. The IPTW-adjusted linear mixed model revealed that IC patients had slightly more deterioration in kidney function over time, but this was not statistically significant (estimate, 0.12; P = 0.06). The sensitivity analyses yielded a similar trend, in that GFR decrease appeared to be greater in the IC cohort. This trend was statistically significant when using Modification of Diet in Renal Disease (P = 0.04). CONCLUSIONS: Among highly selected patients with an NB, deterioration of kidney function may potentially be lower over time than among IC patients. However, the statistical significance varied between analyses and we cautiously attribute these observed differences to patient selection.

How the Beneficial Effects of Alvimopan Differ With Surgical Approach for Radical Cystectomy.

OBJECTIVE: To assess whether the beneficial perioperative effects of alvimopan differ with surgical approach for patients who undergo open radical cystectomy (ORC) vs robot-assisted radical cystectomy (RARC). METHODS: This retrospective study reviewed all patients who underwent cystectomy with urinary diversion at our institution between January 1, 2007, and January 1, 2018. Data were collected on demographic characteristics, comorbidities, surgical approach, alvimopan therapy, hospital length of stay (LOS), days until return of bowel function (ROBF), and complications. Outcomes and interactions were evaluated through regression analysis. RESULTS: Among 573 patients, 236 (41.2%) underwent RARC, 337 (58.8%) underwent ORC, and 205 (35.8%) received alvimopan. Comparison of 4 cohorts (ORC with alvimopan, ORC without alvimopan, RARC with alvimopan, and RARC without alvimopan) showed that patients who underwent ORC without alvimopan had the highest rate of postoperative ileus (25.6%, P = .02), longest median hospital LOS (7 days, P < .001), and longest time until ROBF (4 days, P < .001). On multivariable analysis, the interaction between surgical approach and alvimopan use was significant for the outcome of ROBF (estimate, 1.109; 95% confidence interval, 0.418-1.800; P = .002). In the RARC cohort, multivariable analysis showed no benefit of alvimopan with respect to ileus (P = .27), LOS (P = .09), or ROBF (P = .36). Regarding joint effects of robotic approach and alvimopan, RARC had no effect on gastrointestinal tract outcomes. CONCLUSION: We observed a diminished beneficial effect of alvimopan among patients undergoing RARC and a statistically significant benefit of alvimopan among patients undergoing ORC. The implications of these findings may permit more selective medication use for patients who would benefit the most from this drug.

Robot Assisted Radical Cystectomy vs Open Radical Cystectomy: Over 10 years of the Mayo Clinic Experience.

OBJECTIVES: There is scant information about intermediate / long-term comparative outcomes between robot assisted radical cystectomy (RARC) and open radical cystectomy (ORC). The purpose of this study is to present survival and oncological outcomes between bladder cancer patients who undergo RARC vs. ORC with an overall median follow-up of over 5 years. MATERIALS AND METHODS: A query of all patients who underwent radical cystectomy between January, 2007 and January, 2018 at Mayo Clinic Arizona yielded 595 patients. After excluding cystectomy performed for nonmalignant indication, cancer secondary to nonbladder primary, and cancers with grossly metastatic disease at the time of surgery, 481 patients remained. Data was collected on patient demographics, preoperative information, operative details, complications, and follow-up. Statistical analyses were generated using SPSS 22.0. RESULTS: In 481 total patients, 203 (42.2%) underwent RARC and 278 (57.8%) underwent ORC. The median follow-up for the entire cohort was 66 months. The 5-year recurrence-free survival (RFS) was 70.8% vs. 64.7% and the 10-year RFS was 69.6% vs. 62.7% for the RARC vs. ORC, respectively (P = 0.135). The 5-year overall survival (OS) was 58.9% vs. 57.7% and the 10-year OS was 39.9% vs. 45.6% for RARC vs. ORC patients, respectively (P = 0.466). There were no differences in any recurrence patterns, including the incidence of atypical recurrences (1.5% vs. 1.8% [P = 0.786], respectively). A Cox-proportional hazards model was fitted that included independent predictors of RFS and OS. The results revealed no difference in RFS (HR 1.235, 95% CI: 0.832-1.833, P = 0.295) or OS (HR 0.790, 95% CI: 0.550-1.135, P = 0.202) between the respectively. CONCLUSIONS: Recurrence free survival, OS, and recurrence patterns are similar in bladder cancer patients who undergo either RARC or ORC.

Robot Assisted Surgery of the Vena Cava: Perioperative Outcomes, Technique, and Lessons Learned at The Mayo Clinic.

Introduction: This study aims to describe robot assisted surgery of the inferior vena cava (IVC) by assessing techniques utilized, perioperative outcomes, complications, and long-term patency of the IVC. Methods: A retrospective review was performed on all robotic surgeries involving dissection and repair of the IVC at our institution. Patient characteristics, operative reports, and follow-up visits were analyzed. Preoperative and postoperative imaging was independently reviewed by a single radiologist to determine changes in IVC diameter. Complications were analyzed according to early (<30 days) vs late (>30 days). Results: Thirty-four patients underwent robot assisted surgery of the vena cava from 2008 to 2018. Twenty-six cases were performed for urologic malignancy, four were performed for IVC filter explantation, and four renal vein transpositions were performed for nutcracker syndrome. Twenty-four of the 26 patients with urologic malignancy underwent radical nephrectomy with IVC tumor thrombectomy. Three cases were converted to open. Median length of stay was two nights, and mean estimated blood loss (EBL) was 375 mL. There were five complications, ranging from Clavien-Dindo grade II-IIIa, four of which were early complications. No patients required return to the operating room, and there were no perioperative mortalities. IVC diameter was reduced by 41% on axial diameter, with no patients experiencing compromised venous return. Conclusion: Robot assisted surgery offers the advantage of minimally invasive surgery with the ability to apply open surgical principles. In our series, an experienced multidisciplinary team approach yielded low EBL, short length of stay, and low complication rates.

Assessing tumor extent on contrast-enhanced spectral mammography versus full-field digital mammography and ultrasound.

OBJECTIVES: To compare breast cancer size measurements on full-field digital mammography (FFDM), contrast-enhanced spectral mammography (CEDM), and ultrasound (US), with histologic tumor size used as the reference standard. Material and methods The HIPAA complaint, IRB approved study comprised 88 women with newly diagnosed breast cancer who underwent FFDM and CEDM;74 also had US. Breast density, histologic subtype, and maximum tumor measurements were recorded. RESULTS: Pearson correlation coefficients for FFDM, US, and CEDM vs histopathology were 0.598, 0.639, and 0.859, respectively (P<0.001). The following correlation coefficients were calculated for dense breasts (n=48): histopathology vs FFDM (0.555), US (0.633), and CEDM (0.843) (P<0.001); for nondense breasts (n=40), they were FFDM (0.618), US (0.512), and CEDM (0.885) (P<0.001). For size difference, the mean (SD) for histopathology vs FFDM, US, and CEDM was -1.3 (11.9) mm, -2.8 (11.1) mm, and 2.9 (9.5) mm, respectively. Limits of agreement were -24.8 to 22.0mm, -24.5 to 18.8mm, and -15.6 to 21.4mm, respectively. CONCLUSIONS: In patients with biopsy-proven malignancy, size measurements correlated well with histopathologic size, and were higher on CEDM than those for FFDM and US in patients with dense or nondense breasts. The added value of CEDM as a supplement to FFDM in determining tumor size, however, was greater in patients with dense breasts. CEDM may be a promising alternative preoperative measurement tool for breast cancer patients with dense breasts and/or limited access or contraindications to MRI.