Multimodality Imaging Review of HER2-positive Breast Cancer and Response to Neoadjuvant Chemotherapy

Human epidermal growth factor receptor 2 (HER2/neu or ErbB2)-positive breast cancers comprise 15%-20% of all breast cancers. The most common manifestation of HER2-positive breast cancer at mammography or US is an irregular mass with spiculated margins that often contains calcifications; at MRI, HER2-positive breast cancer may appear as a mass or as nonmass enhancement. HER2-positive breast cancers are often of intermediate to high nuclear grade at histopathologic analysis, with increased risk of local recurrence and metastases and poorer overall prognosis. However, treatment with targeted monoclonal antibody therapies such as trastuzumab and pertuzumab provides better local-regional control and leads to improved survival outcome. With neoadjuvant treatments, including monoclonal antibodies, taxanes, and anthracyclines, women are now potentially able to undergo breast conservation therapy and sentinel lymph node biopsy versus mastectomy and axillary lymph node dissection. Thus, the radiologist's role in assessing the extent of local-regional disease and response to neoadjuvant treatment at imaging is important to inform surgical planning and adjuvant treatment. However, assessment of treatment response remains difficult, with the potential for different imaging modalities to result in underestimation or overestimation of disease to varying degrees when compared with surgical pathologic analysis. In particular, the presence of calcifications at mammography is especially difficult to correlate with the results of pathologic analysis after chemotherapy. Breast MRI findings remain the best predictor of pathologic response. The authors review the initial manifestations of HER2-positive tumors, the varied responses to neoadjuvant chemotherapy, and the challenges in assessing residual cancer burden through a multimodality imaging review with pathologic correlation. ^© RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.

Breast Malignancies After Mastectomy With Autologous or Implant Reconstruction

There are multiple indications for mastectomy for breast cancer, including extent of tumor, inability to achieve negative margins after re-excision, patient preference, or prevention in women with a high lifetime risk of breast cancer. Multiple types of autologous or implant reconstruction options are available for cosmesis. Although rare, breast cancers after mastectomy can occur, and it is important for both surgeons and radiologists to be aware of the associated risk factors, common locations, and classic imaging features of these malignancies. This article reviews the types of mastectomies, reconstruction options, and information about the location, presentation, and prognosis of cancers in the reconstructed breast.

Fetal Ultrasound and Magnetic Resonance Imaging Findings in Suspected Septo-Optic Dysplasia: A Diagnostic Dilemma

OBJECTIVES

To investigate prenatal imaging findings supporting a diagnosis of suspected septo-optic dysplasia (SOD) by fetal ultrasound (US), magnetic resonance imaging (MRI), or both.

METHODS

A retrospective review identified 11 patients with SOD: 9 had a clinical diagnosis of SOD postnatally, and 2 were terminated on the basis of suspicious prenatal imaging. Prenatal and neonatal imaging of the cavum septi pellucidi (CSP), frontal horns (FHs), and lateral ventricles was evaluated.

RESULTS

The appearance of the CSP varied on US and MRI. Complete ("fused") FHs or partial absence of the CSP was reported in 6 of 11 patients by fetal US and 7 of 8 patients by fetal MRI. The diagnosis of SOD was prospectively suspected prenatally in 6 of 11 and in an additional 5 of 11 cases retrospectively. Fetal MRI incorrectly initially reported normal morphologic abnormalities for 2 cases with partial absence of the CSP, whereas US accurately identified the morphologic abnormalities in 1 of these cases before MRI. Imaging features were first suggested at anatomic US (4 patients) and follow-up prenatal US (2 patients). Neonatal imaging was concordant in all 9 live births: 5 completely absent CSP, 3 partially absent CSP, and 1 completely present CSP. Clinical manifestations included optic nerve hypoplasia (9 of 9), panhypopituitarism (5 of 9), and neurodevelopmental delays.

CONCLUSIONS

Primary imaging features of SOD are "continuous" FHs with complete or partial absence of the CSP. Septo-optic dysplasia can be suspected in utero and can appear isolated but has substantial associated central nervous system anomalies identified on fetal MRI or after birth. Partial absence of the CSP can be a prenatal sign of suspected SOD, although fetal MRI lacked the spatial resolution to identify it accurately in all cases.

Metabolic syndrome in pediatric renal transplant recipients: comparing early discontinuation of steroids vs. steroid group

Steroids have played a valuable role in transplantation as a treatment option. The purpose of this study is to assess the prevalence of MS in pediatric RT patients receiving SG or early SWG; SG discontinued five days after transplantation. We retrospectively reviewed 58 pediatric RT patients between 2000 and 2007. MS criterion was defined as the presence of any three of five criteria: (i) BMI >97th percentile, (ii) hypertension (SBP/DBP > 95th percentile or on medications); (iii) triglycerides > 95thpercentile, (iv) HDL cholesterol < 5th percentile, (v) fasting glucose > 100 mg/dL. Twenty-five patients (43%) received SG and 33 patients (57%) received SWG. The prevalence of MS in SG was 68% compared to 15% in SWG. At six months and one yr after transplantation, mean serum glucose, total cholesterol, and triglycerides were significantly lower in the SWG. The prevalence of hypertension was significantly lower in the SWG, and patients in the SWG received significantly less lipid-lowering and anti-hypertensive medications than SG. Mean BMI percentile was significantly higher in SG one yr after transplantation but not after six months, although always significantly higher in patients with MS (p < 0.05). From this study, we conclude that for pediatric RT patients, cardiovascular risk factors are significantly lower in SG withdrawal groups.