T2-fluid attenuated inversion recovery mismatch in tumefactive multiple sclerosis.

The T2-fluid attenuated inversion recovery (FLAIR) mismatch sign has been suggested as an imaging marker of isocitrate dehydrogenase-mutant 1p/19q non-codeleted gliomas with 100% specificity. Tumefactive demyelination is a common mimic of neoplasm that has led to unnecessary biopsies and even resections. We report a case of tumefactive multiple sclerosis in a 46-year-old male without prior symptomatic demyelinating episodes that demonstrates the T2-FLAIR mismatch sign. Our findings suggest the T2-FLAIR mismatch sign should not be used as a differential feature between glioma and tumefactive demyelination. Because typical isocitrate dehydrogenase-mutant 1p/19q non-codeleted gliomas typically do not demonstrate significant enhancement, such diagnosis should be reserved when post-contrast images are unavailable.

Characteristics and Outcomes of Lung Cancers Detected on Low-Dose Lung Cancer Screening CT.

BACKGROUND: Lung cancer screening (LCS) with low-dose CT (LDCT) was implemented in the United States following the National Lung Screening Trial (NLST). The real-world benefits of implementing LCS are yet to be determined with outcome-oriented data. The study objective is to investigate the characteristics and outcomes of screening-detected lung cancers. METHODS: This single-institution retrospective study included LCS patients between June 2014 and December 2019. Patient demographics, number of screening rounds, imaging features, clinical workup, disease extent, histopathology, treatment, complications, and mortality outcomes of screening-detected lung cancers were extracted and compared with NLST data. RESULTS: LCS LDCTs (7,480) were performed on 4,176 patients. The cancer detection rate was 3.8%, higher than reported by NLST (2.4%, P < 0.0001), and cancers were most often found in patients ≥65 years (62%), older than those in NLST (41%, P < 0.0001). The patients' ethnicity was similar to NLST, P = 0.87. Most LCS-detected cancers were early stage I tumors (71% vs. 54% in NLST, P < 0.0001). Two thirds of cancers were detected in the first round of screening (67.1%) and were multifocal lung cancers in 15%. As in NLST, the complication rate after invasive workup or surgery was low (24% vs. 28% in NLST, P = 0.32). Over a median follow-up of 3.3 years, the mortality rate was 0.45%, lower than NLST (1.33%, P < 0.0001). CONCLUSIONS: LCS implementation achieved a higher cancer detection rate, detection of early-stage cancers, and more multifocal lung cancers compared with the NLST, with low complications and mortality. IMPACT: The real-world implementation of LCS has been successful for detection of lung cancer with favorable outcomes.

Clinical and Imaging Features of Non-Small-Cell Lung Cancer in Young Patients.

BACKGROUND: Non-small-cell lung cancer (NSCLC) in young adult patients is rare, with scarce data available in patients aged < 40 years and even less in those aged < 35 years. Our goal was to determine the presenting symptoms, clinicopathologic characteristics, and imaging features of young patients with NSCLC at time of diagnosis and compare them to those of older adults. PATIENTS AND METHODS: We retrospectively analyzed the medical records and imaging of young patients (≤ 40 years old) with NSCLC treated at our institution between 1998 and 2018. Patients < 35 years old were compared to those between 35 and 40 years old. Characteristics of patients ≤ 40 years old were compared to older patients (> 40 years) from publicly available data sets. RESULTS: We identified 166 young patients with NSCLC (median age, 36.6 years; range, 18-40 years). Most presented with nonspecific respiratory symptoms and were diagnosed with pneumonia (84/136, 62%). Compared to patients < 35 years old, patients 35-40 years old were more likely to have malignancy detected incidentally (15% vs. 5%, P = .04). Patients < 35 years old were more likely to have central tumors (55% vs. 33%, P = .02) and to have bone (38% vs. 19%, P = .007) and lung (39% vs. 24%, P = .03) metastases. Compared to older patients (> 40 years), young patients were more likely to be never smokers (65.0% vs. 14.7%, P < .001) and to have advanced disease (88% vs. 66%, P < .001). CONCLUSION: Young patients with NSCLC often present with nonspecific symptoms and have advanced disease at diagnosis, often mimicking other pathologies. Awareness of the clinical presentation and imaging features of NSCLC in young patients may help minimize delays in diagnoses.

Target-specific yield rate and clinical utility of percutaneous tissue sampling in spinal infection.

BACKGROUND: Percutaneous tissue sampling in spondylodiscitis is frequently performed but with highly variable yield in literature and unclear clinical impact. Factors that influence the culture success rate are not well established. OBJECTIVE: To determine target specific yield and clinical impact of percutaneous biopsy in clinically and imaging diagnosed spinal infection and factors that may influence the yield rate. METHODS: Institutional review board approved single center retrospective chart review from 2015 to 2019 analyzing imaging findings, clinical notes, procedural reports, and laboratory results on cases of concurrent imaging and clinically diagnosed spondylodiscitis that underwent percutaneous tissue sampling. RESULTS: A total of 111 patients and 189 specimens were analyzed. The overall culture yield in spondylodiscitis was approximately 27%, 9% affecting management. Abscess/fluid and septic arthritis aspirations had higher yield rates compared to soft tissue/phlegmon aspirations. Core sampling of the bone and disc yielded positive culture 12% of the time, 2% resulted in change in management. Upper thoracic spine biopsies were more frequently positive and associated with change in management. Positive culture elsewhere in the body represented the major reason underlying lack of clinical impact. Lack of prior antibiotic treatment and diabetes mellitus demonstrated a trend toward higher culture positivity, although a larger sample size is needed to confirm these findings. No repeat biopsy yielded positive culture. Staphylococcus spp. accounted for approximately half of the microorganisms cultured. In positive biopsies where infection was also found elsewhere in the body, the organism was nearly always congruent (96%).

Association between circulating tumor DNA burden and disease burden in patients with ALK-positive lung cancer.

BACKGROUND: Plasma genotyping is an emerging approach for the identification of genetic alterations mediating resistance to anaplastic lymphoma kinase (ALK)-targeted therapy. The authors reviewed plasma genotyping and imaging findings to assess the correlation between circulating tumor DNA (ctDNA) burden and disease burden in patients with ALK-positive lung cancer. METHODS: The authors analyzed 97 plasma specimens from 75 patients with ALK-positive lung cancer to identify ALK and non-ALK alterations. Disease burden was estimated by tabulating lesions per organ and calculating lesion diameters, areas, and volumes. Disease burden was correlated with the allelic frequency (AF) of plasma alterations. RESULTS: The mean interval between plasma collection and imaging was 8 days. ctDNA was detected in approximately 85% of plasma specimens. An ALK fusion and ALK mutation were detected in 79% and 76%, respectively, of plasma specimens. Using the maximum plasma alteration AF and maximum ALK alteration AF as independent surrogates of ctDNA burden, a higher disease burden measurement on imaging was found to be associated with higher ctDNA burden. Total body and extrathoracic tumor volume but not intrathoracic tumor volume correlated with ctDNA burden. Of all the disease sites assessed, the ctDNA burden correlated most with involvement of the liver, bones, and adrenal glands. Despite being the defining alteration in ALK-positive lung cancer, isolated plasma ALK fusion AF did not perform as well as the maximum plasma alteration AF or maximum ALK alteration AF for correlating tumor burden. CONCLUSIONS: In patients with ALK-positive lung cancer, the maximum plasma alteration AF and maximum ALK alteration AF correlate with the extrathoracic burden of disease and are more predictive of tumor burden compared with the ALK fusion AF alone. LAY SUMMARY: Analysis of genetic material shed from cancer cells into the circulation offers insights into the molecular composition of tumors. The circulating tumor DNA (ctDNA) varies over time and across individuals and is impacted by the distribution of disease. Herein, the authors estimated tumor burden on imaging and correlated it with ctDNA by calculating the maximum allelic frequency. The current study findings demonstrated that the greatest correlation exists between extrathoracic, extracranial tumor burden (particularly involvement of the liver, adrenal glands, or bones) and ctDNA burden, suggesting a biological basis for the interpatient and temporal intrapatient differences in ctDNA yield that have been described in previous studies.

Vascular magnetic resonance angiography techniques.

Magnetic resonance angiography (MRA) denotes a unique option for the evaluation of peripheral vasculature due to its noninvasive nature, lack of ionizing radiation exposure, potential for non-contrast examination, and ability for generating volumetric representations that showcase vascular pathology. The constant evolution of the available MRA techniques, however, makes understanding and determining an optimal imaging protocol difficult. Here we present a brief overview of the major MRA sequence options, their major weaknesses and strengths, and related imaging considerations. Understanding the technical underpinnings of the various MRA methods helps with recognition of common imaging issues and artifacts and rendering clinically relevant interpretations.

Systematic review of civilian intravascular ballistic embolism reports during the last 30 years.

BACKGROUND: Intravascular ballistic embolization is a rare complication of missile injury. Because of its rarity, much remains to be known about its presentation, pathophysiology, complications, and management. In this study, we analyze case reports of ballistic embolization in the last 30 years and available cases from our institution to determine the likely patient, the nature of the embolization, the possible complications, and a general management strategy. METHODS: A PubMed search was performed in search of missile embolization cases from 1988 to 2018 in the English language, including only cases of intravascular emboli. Cases resulting from combat and explosive devices were excluded. In addition, five cases from our institution were included in the analysis. RESULTS: A total of 261 cases were analyzed. The most common presentation was that of a young man (reflecting the demographics of those sustaining gunshot wound injuries) with injury to the anterior torso from a single gunshot wound. Venous entry was most common, most often through large-caliber vessels. There was roughly equal involvement of the right and left circulation. Left circulation emboli were frequently symptomatic, with ischemia being the most frequent sequela. In contrast, a right circulation embolus was rarely associated with significant complications. CONCLUSIONS: Despite its rarity, ballistic embolization should be considered in gunshot injury with known large-vessel injury when an exit wound is not identified. In particular, signs of ischemia distant from the injury site warrant timely investigation to maximize tissue salvageability. We present a management strategy model for consideration.

The Radiologic and Pathologic Diagnosis of Biphasic Pulmonary Blastoma.

Pulmonary blastomas are rare malignancies, representing 0.25% to 0.5% of all primary lung neoplasms with often aggressive progression and poor prognosis. Clinical management of pulmonary blastomas depends on histologic subtype, staging, and presentation, and may consist of surgery, chemotherapy, and radiation. Biphasic pulmonary blastoma is a subtype of pulmonary blastoma that exhibits biphasic histology, with both epithelial and mesenchymal malignant elements. We report a case of biphasic pulmonary blastoma in a 33-year-old female with 1 pack per day history of smoking for approximately 16 years, who presented with left-sided pleuritic chest pain on deep inspiration without otherwise significant pat medical history. Imaging evaluation using chest radiography, computed tomography, and magnetic resonance imaging identified a heterogenous, well-circumscribed, left lower lobe mass with extensive necrosis and hemorrhage. No lymphadenopathy or distant metastasis was detected through imaging evaluation. Surgical resection of the tumor followed by histopathological analysis confirmed a biphasic pulmonary blastoma.

A Concurrent Case of Ménétrier's Disease and Signet Ring Carcinoma.

Ménétrier's disease, also known as hyperplastic protein-losing gastropathy, is a rare, idiopathic, acquired, premalignant condition associated with gastric carcinoma. Its association with signet ring cell cancer of the stomach has been previously reported only twice. We present the third case of histologically confirmed concurrent Ménétrier's disease with signet ring carcinoma of the stomach, interrogated by esophagogastroduodenoscopy and endoscopic ultrasound.

Coronary-Pulmonary Artery Fistulas: A Systematic Review.

PURPOSE: Coronary-pulmonary arterial fistulas (CPAFs) are rare coronary artery anomalies that have been described only in limited case reports. This study aims to evaluate the clinical presentation and imaging findings of CPAFs collected from 6 participating medical centers along with CPAFs reported in the literature, to discern any general trends present in CPAFs. MATERIALS AND METHODS: A total of 25 cases of CPAF diagnosed by coronary computed tomography angiography were collected across 6 participating institutions. In addition, utilizing a PubMed literature search, 78 additional CPAF cases were obtained. The imaging findings and relevant clinical history were reviewed. RESULTS: Of the 103 CPAF patients, 60 (63% of patients with sex known) were male, with ages ranging from newborn to 88 years (mean=46.1 y). The most common symptoms reported were chest pain (n=40, 39%) and dyspnea (n=26, 25%), with a murmur as the most common physical examination finding (n=38, 37%). The most common coronary artery of origin for a CPAF was the left main/left anterior descending (n=87, 84%), followed by the right coronary artery (n=39, 38%). The fistula most commonly terminated in the main pulmonary artery (n=92, 89%). Multiple CPAFs were present in 46 cases (45%). Coronary artery aneurysms were identified in 20 cases (19%). Pediatric CPAF cases were usually associated with pulmonary atresia with ventricular septal defect. CONCLUSIONS: CPAFs are seen in a variety of clinical settings, from infants with advanced congenital heart disease to elderly patients who have undergone revascularization surgery. Although coronary artery fistulas have previously been described as rarely involving multiple coronary arteries, with the right coronary artery being most often involved, our series demonstrates that multiple fistulas are commonly present, with the most common pattern being between the left main/left anterior descending and the main pulmonary trunk.