Fat Embolism Syndrome Mimicking Thrombotic Thrombocytopenic Purpura in a Patient With Hemoglobin S/Beta-Thalassemia.

Thrombotic microangiopathies cause ischemic organ damage and require urgent management for a favorable prognosis. Fat embolism syndrome from bone marrow necrosis is a rare and unique pathology that carries a high mortality rate. It can mimic thrombotic microangiopathies such as thrombotic thrombocytopenic purpura (TTP). Herein, we present a patient with sickle cell-beta-thalassemia who initially presented with a vaso-occlusive crisis, lab evidence of hemolysis, schistocytes and thrombocytopenia who developed acute encephalopathy with respiratory distress, consistent with TTP. She was found to have multiple infarcts in the brain. She was intubated and underwent plasma and red cell exchange. Bone marrow biopsy confirmed marrow necrosis from her vaso-occlusive crisis and subsequently, fat embolism syndrome. Here, we discuss the complex presentation and the complications of fat embolism from bone marrow necrosis and how it can mimic TTP.

Neurotoxicity: A Rare Side Effect of Programmed Cell Death 1 (PD-1) Inhibitors.

Immunotherapy is a biological therapy that helps the body's immune system to fight against cancer cells. The Food and Drug Administration (FDA) approved the first immune checkpoint inhibitor in 2011. Since 2011, many immune checkpoint inhibitors have been approved. Programmed cell death 1 (PD-1) inhibitors are now commonly used in multiple malignancies due to their remarkable response. Thus, immune-related adverse events are now coming into the limelight due to the increasing use of PD-1 inhibitors. Here, we present a case of a 54-year-old female with non-small cell lung cancers (NSCLC) treated with pembrolizumab and later presented with severe neurotoxicity.

Renal Mucosa-Associated Lymphoid Tissue (MALT) Associated End-Stage Renal Disease in a Patient Presenting With Diarrhea.

Extranodal marginal zone lymphoma (MZL) of mucosa-associated lymphoid tissue (MALT) is most commonly found in the GI tract. Other less common anatomical sites for MALT include the skin, intestine, salivary glands, lungs, and ocular adnexa. Isolated MALT of the kidney has only been sporadically reported. Most of the reported cases in the literature present with underlying renal mass and are generally diagnosed post nephrectomy. We present a case of a 73-year-old gentleman with biopsy-proven primary MALT of the kidney who presented with acute kidney injury (AKI) in the background of Clostridium difficile (C. difficile) colitis. However, our patient did not have a renal mass a renal biopsy was performed due to accelerated deterioration of renal function. Due to the inherent heterogeneity of the disease, it is challenging to have a unifying treatment strategy for MALT with treatment varying with the anatomical site. We also discuss current and prospective treatment strategies for MALT and marginal zone lymphoma in general.

A Case of Intermittent Left Bundle Branch Block.

An 82-year-old woman with uncontrolled hypertension and occasional exertional dyspnea was found to be in intermittent left bundle branch block (LBBB). Her laboratory results, echocardiogram, and ischemic workup were unremarkable. This case highlights that intermittent LBBB is not always associated with coronary ischemia, vasospasm, blunt cardiac injury, drugs, and high catecholaminergic or inflammatory states.

Stroma-targeting strategies in pancreatic cancer: Past lessons, challenges and prospects.

Pancreatic ductal adenocarcinoma (PDAC) is projected to emerge as the second leading cause of cancer-related death after 2030. Extreme treatment resistance is perhaps the most significant factor that underlies the poor prognosis of PDAC. To date, combination chemotherapy remains the mainstay of treatment for most PDAC patients. Compared to other cancer types, treatment response of PDAC tumors to similar chemotherapy regimens is clearly much lower and shorter-lived. Aside from typically harboring genetic alterations that to date remain un-druggable and are drivers of treatment resistance, PDAC tumors are uniquely characterized by a densely fibrotic stroma that has well-established roles in promoting cancer progression and treatment resistance. However, emerging evidence also suggests that indiscriminate targeting and near complete depletion of stroma may promote PDAC aggressiveness and lead to detrimental outcomes. These conflicting results undoubtedly warrant the need for a more in-depth understanding of the heterogeneity of tumor stroma in order to develop modulatory strategies in favor of tumor suppression. The advent of novel techniques including single cell RNA sequencing and multiplex immunohistochemistry have further illuminated the complex heterogeneity of tumor cells, stromal fibroblasts, and immune cells. This new knowledge is instrumental for development of more refined therapeutic strategies that can ultimately defeat this disease. Here, we provide a concise review on lessons learned from past stroma-targeting strategies, new challenges revealed from recent preclinical and clinical studies, as well as new prospects in the treatment of PDAC.