The role of diffusion weighted imaging as supplement to dynamic contrast enhanced breast MRI: Can it help predict malignancy, histologic grade and recurrence?

RATIONALE AND OBJECTIVES: To evaluate the value of adding Diffusion Weighted Imaging (DWI) with Apparent Diffusion Coefficient (ADC) mapping to dynamic contrast enhanced (DCE-MRI) to distinguish benign from malignant pathology subtypes and tumor recurrence. METHOD AND MATERIALS: In this retrospective IRB approved study, 956 consecutive patients underwent bilateral breast MRI between 1/2015 and 12/2015, with 156 BIRADS 4, 5, or 6 lesions detected in 111 patients. DWI imaging at B0, B100, B600, B1000 was performed with DCE-MRI. Values for diffusion and ADC images were recorded by two fellowship-trained breast radiologists. Mean ADC and signal intensity (SI) values were correlated with histology, tumor grade, hormone receptors (ER, PR, and HER-2)and Oncotype DX scores, when available. p ≤ 0.05 was considered significant. RESULTS: Of 156 lesions, there were 59 (38%) benign lesions, 24 (15%) Ductal Carcinoma In-Situ, 47 (30%) Invasive Ductal Carcinoma (IDC), 15 (10%) Invasive Lobular Carcinoma (ILC) and 2 (2%) Mucinous carcinoma (MC), five (5%) mixed IDC and ILC, and four (4%) other, including tubular and rare types of malignancy. Mean ADC values for malignancy were significantly lower than for benign lesions (1085 ± 343 × 10-6 vs 1481 ± 276 × 10-6 mm2/s), which is highly predictive (area under curve = 0.82). In addition, tumors with PR negativity and Oncotype score ≥18 (intermediate to high risk for recurrence) demonstrated significantly lower ADC values. SI at B100 and B600 was helpful in distinguishing benign versus IDC. There was no significant correlation between ADC values and tumor grade or ER/HER2 status. CONCLUSION: ADC value is important factor in distinguishing malignancy, differentiating tumors with higher Oncotype score, and PR negativity. Therefore, it can be used as an important tool to assist appropriate treatment selection.

MR Imaging of the Female Perineum: Clitoris, Labia, and Introitus.

The female perineum has a complex anatomy and can be involved by a wide range of pathologies. In this article, we specifically focus on the clitoris, labia, and introitus. We discuss the normal anatomy of these structures, the MR imaging techniques to optimize their evaluation, and several common and uncommon entities that may affect them, including benign and malignant tumors, as well as infectious and inflammatory, vascular, iatrogenic, and developmental entities.

Limited added utility of performing follow-up contrast-enhanced CT in patients undergoing initial non-enhanced CT for evaluation of flank pain in the emergency department.

In our emergency department (ED), patients with flank pain often undergo non-enhanced computed tomography (NECT) to assess for nephroureteral (NU) stone. After immediate image review, decision is made regarding need for subsequent contrast-enhanced CT (CECT) to help assess for other causes of pain. This study aimed to review the experience of a single institution with this protocol and to assess the utility of CECT. Over a 6 month period, we performed a retrospective analysis on ED patients presenting with flank pain undergoing CT for a clinical diagnosis of nephroureterolithiasis. Patients initially underwent abdominopelvic NECT. The interpreting radiologist immediately decided whether to obtain a CECT to evaluate for another etiology of pain. Medical records, CT reports and images, and 7-day ED return were reviewed. CT diagnoses on NECT and CECT were compared. Additional information from CECT and changes in management as documented in the patient's medical record were noted. Three hundred twenty-two patients underwent NECT for obstructing NU stones during the study period. Renal or ureteral calculi were detected in 143/322 (44.4 %). One hundred fifty-four patients (47.8 %) underwent CECT. CECT added information in 17/322 cases (5.3 %) but only changed management in 6/322 patients (1.9 %). In four of these patients with final diagnosis of renal infarct, splenic infarct, pyelonephritis and early acute appendicitis in a thin patient, there was no abnormality on the NECT (4/322 patients, 1.2 %). In the remaining 2 patients, an abnormality was visible on the NECT. In patients presenting with flank pain with a clinical suspicion of nephroureterolithiasis, CECT may not be indicated. While CECT provided better delineation of an abnormality in 5.3 % of cases, changes in management after CECT occurred only in 2 %. This included 1 % of patients in whom a diagnosis of organ infarct, pyelonephritis or acute appendicitis in a thin patient could only be made on CECT.

Combined adrenal and ovarian venous sampling to localize an androgen producing tumor.

A postmenopausal woman presented with hirsutism and elevated serum testosterone levels. A 1-cm adrenal adenoma was noted on computed tomography. Combined adrenal and ovarian venous sampling was performed to localize an androgen producing tumor to the left ovary. The patient underwent a bilateral salpingo-oophrectomy and was spared an unnecessary adrenalectomy.

ICOS costimulation expands Th2 immunity by augmenting migration of lymphocytes to draining lymph nodes.

The T cell costimulatory molecule ICOS regulates Th2 effector function in allergic airway disease. Recently, several studies with ICOS(-/-) mice have also demonstrated a role for ICOS in Th2 differentiation. To determine the effects of ICOS on the early immune response, we investigated augmenting ICOS costimulation in a Th2-mediated immune response to Schistosoma mansoni Ags. We found that augmenting ICOS costimulation with B7RP-1-Fc increased the accumulation of T and B cells in the draining lymph nodes postimmunization. Interestingly, the increased numbers were due in part to increased migration of undivided Ag-specific TCR transgenic T cells and surprisingly B cells, as well as non-TCR transgenic T cells. B7RP-1-Fc also increased the levels of the chemokines CCL21 and CXCL13 in the draining lymph node, suggesting ICOS costimulation contributes to migration by direct or indirect effects on dendritic cells, stromal cells and high endothelial venules. Further, the effects of B7RP-1-Fc were not dependent on immunization. Our data support a model in which ICOS costimulation augments the pool of lymphocytes in the draining lymph nodes, leading to an increase in the frequency of potentially reactive T and B cells.