Gastrointestinal lymphoma is an uncommon disease but is the most frequently occurring extranodal lymphoma and is almost exclusively of non-Hodgkin type. Primary gastrointestinal lymphoma most commonly involves the stomach but can involve any part of the gastrointestinal tract from the esophagus to the rectum. Risk factors for the development of gastrointestinal lymphoma include Helicobacter pylori infection, immunosuppression after solid organ transplantation, celiac disease, inflammatory bowel disease, and human immunodeficiency virus infection. Although gastrointestinal lymphoma has a wide variety of imaging appearances and definitive diagnosis relies on histopathologic analysis, certain findings (eg, a bulky mass or diffuse infiltration with preservation of fat planes and no obstruction, multiple site involvement, associated bulky lymphadenopathy) can strongly suggest the diagnosis. Imaging also plays an important role in the detection of complications such as perforation, obstruction, and fistulization. The most commonly used imaging modalities are barium examination and computed tomography (CT). These modalities are complementary, although CT provides a better overall assessment of the disease stage.

Limited data exist on safety and efficacy of immune checkpoint inhibitors (ICIs) among organ transplant recipients. The objective of this study was to report a case series of two patients with renal transplant who received treatment with an ICI and to conduct a pooled analysis of published cases to describe the safety and efficacy of ICIs in organ transplant patients. A systematic search in the Google Scholar and PubMed databases was carried out to include all the published cases of organ transplant patients who received treatment with ICIs including programmed cell death protein 1 (PD‐1), programmed death‐ligand 1, or cytotoxic lymphocyte antigen‐4 inhibitors since their inscription to January 31, 2019. In the present series of two cases with renal allografts who received pembrolizumab, one patient with squamous cell carcinoma of the skin experienced complete response (CR), whereas another patient with melanoma had a mixed response. Both patients experienced allograft rejection, but graft was salvaged. The pooled analysis of 64 patients published in literature showed that overall allograft rejection rate is 41% in organ transplant recipients following ICI therapy. The graft rejection rate was 44% (17/39) for renal, 39% (7/19) for liver, and 20% (1/5) for cardiac allografts. The highest risk was seen among patients who were treated with PD‐1 inhibitors, 20/42 (48%)—13/24 (54%) on nivolumab and 7/18 (39%) on pembrolizumab. The risk was lowest with ipilimumab, 23% (3/13). The overall response rate (CR + partial response [PR]) was 20% with ipilimumab, 26% with nivolumab, and 53% with pembrolizumab, whereas disease control rate (CR + PR + stable disease) was 35% with ipilimumab, 37% with nivolumab, and 53% with pembrolizumab. None of the variables including age, gender, type of cancer, type of allograft, type of immunosuppression, time since transplantation to initiation of ICI, and prior history of rejection were significantly associated with the transplant rejection on univariate analysis. The efficacy of ICI among patients with organ transplant appears promising, warranting testing in prospective clinical trials. The risk of rejection and allograft loss is considerable; therefore, the risk and alternative form of therapies should be thoroughly discussed with the transplant patients prior to initiating ICI therapy. Implications for Practice Transplant recipients are at higher risk of developing cancers. Although immune checkpoint inhibitors have been shown to improve the outcome in more than one cancer type, transplant recipients were excluded from these trials. Most of the data on the safety and efficacy of immune checkpoint inhibitors in transplant patients are based upon case series and case reports. The pooled data from these reports suggest that anti‐programmed death‐ligand 1 inhibitors have reasonable safety and efficacy among organ transplant patients, which warrants testing in clinical trials.

There was a statistically significant difference in the values of the quantitative shear wave elastography parameters of benign and malignant solid breast masses. By adding shear wave elastography parameters to BI-RADS category 4a masses, we found that about 90% of them could be correctly downgraded to BI-RADS category 3, thereby avoiding biopsy. Elasticity ratio (cutoff, 3.56) appeared to be the most discriminatory parameter.

The cerebral cortex develops in three overlapping stages: cell proliferation, neuronal migration, and cortical organization. Abnormal neuronal migration may result in lissencephaly, which is characterized by either the absence (agyria) or the paucity (pachygyria) of cerebral convolutions. The two main clinicopathologic types of lissencephaly may be differentiated according to their prenatal imaging features. Other cranial and extracranial abnormalities also may occur in association with lissencephaly. The prognosis is often poor, but prenatal diagnosis allows appropriate counseling and optimization of obstetric management. Familiarity with the normal ultrasonographic (US) and magnetic resonance (MR) imaging appearances of the fetal cerebral cortex at various stages of gestation is essential for the early detection of abnormal sulcal development. The primary fissures and sulci that can be examined with prenatal US and MR imaging include the parieto-occipital fissure, calcarine fissure, cingulate sulcus, convexity sulci, and sylvian fissure and insula.