The investigators present their analysis of primary cells from patients with human T-cell leukemia virus 1–associated adult T-cell leukemia/lymphoma treated in a phase 2 clinical trial with nivolumab to elucidate mechanisms of hyperprogression that halted the trial after just 3 patients received a single treatment.

Segmental arterial mediolysis (SAM) is a rare but serious nonatherosclerotic, noninflammatory vasculopathy of unknown etiology that often results in dissection, aneurysm, occlusion, or stenosis of, primarily, the abdominal arteries. Current literature lacks consensus on diagnostic criteria and management options for SAM. This review summarizes 143 cases and aims to advance appropriate recognition and management of SAM. Literature review of all relevant SAM case studies from 2005 to 2018 yielded 126 individual SAM cases from 66 reports. We identified 17 additional SAM cases from our center, bringing our analysis to 143 patients. Patients with SAM were most commonly men (68%) in their 60s. Hypertension (43%), tobacco use (12%), and hyperlipidemia (12%) were common comorbidities. Abdominal pain (80%) and intraabdominal bleeding (50%) were the most common presenting symptoms. Computed tomography was the most frequently used imaging method (78%), and histology was available in 44% of cases. The most commonly affected vessels were the superior mesenteric (53%), hepatic (45%), celiac (36%), renal (26%), and splenic (25%) arteries with aneurysm (76%), dissection (61%), and arterial rupture (46%). Treatments included coil embolization (28%), abdominal organ surgery (24%), open arterial repair (21%), and medical management (20%). Case-specific treatment modalities yielded symptom relief in the vast majority (91%) of patients, with a mortality rate of 7%.

Abdominal aortic aneurysm (AAA) affects 1.1 million people in the United States.¹ Most of these are small aneurysms without indication for immediate repair; they are managed expectantly with imaging surveillance until maximum transverse diameter (MTD) predicts a substantial enough risk of rupture to merit repair. Abdominal aortic aneurysm rupture or complication of repair were the primary cause of nearly 10 000 deaths in 2014 and a contributing cause of more than 17 000 deaths in 2009.^2,3 Ruptured AAA was the 17th leading cause of death in people older than 65 years in 2017.⁴ Understanding AAA growth patterns informs appropriate monitoring intervals. Quiz Ref ID Discrepancies exist in the literature on the most common patterns of AAA growth. Some studies suggest staccato growth patterns^5,6; others suggest exponential growth^7-10; and others present growth as linear.^11,12