Distinguishing benign from malignant adrenal masses

Abstract The approach to the radiological and clinical evaluation of adrenal masses in the oncologic and non-oncologic patient is discussed. In addition, the value of unenhanced and enhanced CT densitometry with emphasis on the washout features to distinguish between lipid-rich and lipid-poor adenomas and malignant lesions is detailed. The roles of magnetic resonance imaging and positron emission tomography in distinguishing benign from malignant adrenal masses will also be discussed.http://deepblue.lib.umich.edu/bitstream/2027.42/111299/1/40644_2015_Article_10.pd

Cystic pancreatic neoplasms

Abstract Cystic pancreatic neoplasms are uncommon, but are being seen more frequently due to the widespread use of cross-sectional imaging. In this article, we will address the clinical and imaging features of the more commonly seen neoplasms. Points of differentiation between these neoplasms, the use of cyst fluid analysis and an approach to the incidentally discovered cystic mass will be addressed.http://deepblue.lib.umich.edu/bitstream/2027.42/111304/1/40644_2015_Article_11.pd

Tight Adherence (Tad) Pilus Genes Indicate Putative Niche Differentiation in Phytoplankton Bloom Associated Rhodobacterales

The multiple interactions of phytoplankton and bacterioplankton are central for our understanding of aquatic environments. A prominent example of those is the consistent association of diatoms with Alphaproteobacteria of the order Rhodobacterales. These photoheterotrophic bacteria have traditionally been described as generalists that scavenge dissolved organic matter. Many observations suggest that members of this clade are specialized in colonizing the microenvironment of diatom cells, known as the phycosphere. However, the molecular mechanisms that differentiate Rhodobacterales generalists and phycosphere colonizers are poorly understood. We investigated Rhodobacterales in the North Sea during the 2010-2012 spring blooms using a time series of 38 deeply sequenced metagenomes and 10 metaproteomes collected throughout these events. Rhodobacterales metagenome assembled genomes (MAGs) were recurrently abundant. They exhibited the highest gene enrichment and protein expression of small-molecule transporters, such as monosaccharides, thiamine and polyamine transporters, and anaplerotic pathways, such as ethylmalonyl and propanoyl-CoA metabolic pathways, all suggestive of a generalist lifestyle. Metaproteomes indicated that the species represented by these MAGs were the dominant suppliers of vitamin B-12 during the blooms, concomitant with a significant enrichment of genes related to vitamin B-12 biosynthesis suggestive of association with diatom phycospheres. A closer examination of putative generalists and colonizers showed that putative generalists had persistently higher relative abundance throughout the blooms and thus produced more than 80% of Rhodobacterales transport proteins, suggesting rapid growth. In contrast, putative phycosphere colonizers exhibited large fluctuation in relative abundance across the different blooms and correlated strongly with particular diatom species that were dominant during the blooms each year. The defining feature of putative phycosphere colonizers is the presence of the tight adherence (tad) gene cluster, which is responsible for the assembly of adhesive pili that presumably enable attachment to diatom hosts. In addition, putative phycosphere colonizers possessed higher prevalence of secondary metabolite biosynthetic gene clusters, particularly homoserine lactones, which can regulate bacterial attachment through quorum sensing. Altogether, these findings suggest that while many members of Rhodobacterales are competitive during diatom blooms, only a subset form close associations with diatoms by colonizing their phycospheres.</p

Isolated portacaval adenopathy in Hodgkin lymphoma CT and US findings

We report a case of isolated portacaval adenopathy as the initial presenting feature in a patient with Hodgkin lymphoma. The differential diagnosis of masses located in the portacaval space is discussed and signs useful to localized tumors to this space are described.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31858/1/0000808.pd

Retroperitoneal extraosseous ewing's sarcoma with renal involvement: US and MRI findings

A case of retroperitoneal extraosseous Ewing's sarcoma (EES) with renal involvement, which simulated an exophytic renal mass, is reported. EES is a rare soft tissue tumor that can occur anywhere in the soft tissues, but is seen most commonly in the extremities. Although EES is histologically similar to osseous Ewing's sarcoma, it is usually found in older patients. EES should be included in the differential diagnosis of soft tissue tumors, especially in the second and third decade of life.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30863/1/0000526.pd

3D excretory MR urography: Improved image quality with intravenous saline and diuretic administration

Purpose To assess the effect of diuretic administration on the image quality of excretory magnetic resonance urography (MRU) obtained following intravenous hydration, and to determine whether intravenous hydration alone is sufficient to produce diagnostic quality studies of nondilated upper tracts. Materials and Methods A total of 22 patients with nondilated upper tracts were evaluated with contrast-enhanced MRU. All patients received 250 mL of saline intravenously immediately prior to the examination. A total of 11 patients received 10–20 mg furosemide in addition to saline. Imaging was performed with a three-dimensional (3D) and two-dimensional (2D) breathhold spoiled gradient-echo sequences. Excretory MRU images were acquired five minutes after the administration of 0.1 mmol/kg gadolinium and were independently reviewed by two radiologists, who were blinded to the MRU technique. Readers evaluated the calyces, renal pelvis, and ureters qualitatively for degree of opacification, distention, and artifacts on a four-point scale. Statistical analysis was performed using a permutation test. Results There was no significant disagreement between the two readers ( P = 0.14). Furosemide resulted in significant improvement in calyceal and renal pelvis distention ( P < 0.005), and significant artifact reduction in all upper tract segments ( P < 0.001) compared to the effect of saline alone. Conclusion Intravenous furosemide significantly improves the image quality of excretory MRU studies obtained following intravenous hydration. Intravenous saline alone is insufficient to produce diagnostic quality studies of the non-dilated upper tracts. J. Magn. Reson. Imaging 2007. © 2007 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/56023/1/20875_ftp.pd

Can endoscopic ultrasound or magnetic resonance cholangiopancreatography replace ERCP in patients with suspected biliary disease? A prospective trial and cost analysis

ERCP is the gold standard for pancreaticobiliary evaluation but is associated with complications. Less invasive diagnostic alternatives with similar capabilities may be cost-effective, particularly in situations involving low prevalence of disease. The aim of this study was to compare the performance of endoscopic ultrasound (EUS) with magnetic resonance cholangiopancreatography (MRCP) and ERCP in the same patients with suspected extrahepatic biliary disease. The economic outcomes of EUS-, MRCP-, and ERCP-based diagnostic strategies were evaluated. METHODS : Prospective cohort study of patients referred for ERCP with suspected biliary disease. MRCP and EUS were performed within 24 h before ERCP. The investigators were blinded to the results of the alternative imaging studies. A cost-utility analysis was performed for initial ERCP, MRCP, and EUS strategies for these patients. RESULTS : A total of 30 patients were studied. ERCP cholangiogram failed in one patient, and another patient did not complete MRCP because of claustrophobia. The final diagnoses ( n = 28 ) were CBD stone (mean = 4 mm; range = 3–6 mm) in five patients; biliary stricture in three patients, and normal biliary tree in 20. Two patients had pancreatitis after therapeutic ERCP, one after precut sphincterotomy followed by a normal cholangiogram. EUS was more sensitive than MRCP in the detection of choledocolithiasis (80% vs 40%), with similar specificity. MRCP had a poor specificity and positive predictive value for the diagnosis of biliary stricture (76%/25%) compared to EUS (100%/100%), with similar sensitivity. The overall accuracy of MRCP for any abnormality was 61% (95% CI = 0.41–0.78) compared to 89% (CI = 0.72–0.98) for EUS. Among those patients with a normal biliary tree, the proportion correctly identified with each test was 95% for EUS and 65% for MRCP ( p < 0.02 ). The cost for each strategy per patient evaluated was $1346 for ERCP,$1111 for EUS, and $1145 for MRCP. CONCLUSIONS : In this patient population with a low disease prevalence, EUS was superior to MRCP for choledocholithiasis. EUS was most useful for confirming a normal biliary tree and should be considered a low-risk alternative to ERCP. Although MRCP had the lowest procedural reimbursement, the initial EUS strategy had the greatest cost-utility by avoiding unnecessary ERCP examinations.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73885/1/j.1572-0241.2001.04245.x.pd

Complete Spontaneous Regression of Pulmonary Metastatic Melanoma

Complete spontaneous regression of melanoma metastatic to the lungs is a rare event. objective . To report a case of biopsy-proven melanoma metastatic to the lung with complete spontaneous regression. methods . Multidisciplinary case report. results . A 35-year-old white female was diagnosed with metastatic melanoma to the lung. A pleural biopsy confirmed the diagnosis. Partial spontaneous regression was noted by a staging computed tomography scan prior to enrollment in an investiga-tional protocol. Complete spontaneous regression occurred over 5 months without any form of conventional or alternative therapy, and the patient remains disease-free 3 years after diagnosis. conclusions . Our case represents the seventh case of complete spontaneous regression of melanoma metastatic to the lung, and the only case with histologic confirmation of both the primary and pulmonary metastatic lesions. The patient was pregnant twice between the time of her initial diagnosis of primary melanoma and pulmonary metastatic disease.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75559/1/j.1524-4725.1998.tb04275.x.pd

The prediction of radiationâ induced liver dysfunction using a local dose and regional venous perfusion model

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134805/1/mp1081.pd

Volume reduction versus radiation dose for tumors in previously untreated lymphoma patients who received iodine-131 tositumomab therapy

BACKGROUND A Phase II study of previously untreated patients with malignant low grade follicular lymphoma given a combination of unlabeled tositumomab and tositumomab labeled with iodine-131 has recently been completed. The responses of these patients have been characterized, and for some of them tumor dosimetry during therapy has been estimated not only by pretherapy tracer conjugate views but also by a hybrid method. METHODS Available patients were studied if they had had a pelvic or abdominal tumor evaluation by single photon emission computed tomography (SPECT) and achieved a partial response. A tumor outlined on the iodine-131 conjugate-view images was called a composite tumor. Its volume estimate came from multiple, not necessarily contiguous, regions of interest (ROI) on the pretherapy computed tomography (CT) scan. Its radiation dose was estimated from the weeklong series of pretherapy images and standard Medical Internal Radiation Dose methods. Computed tomography ROI were also grouped into smaller, contiguous volumes that defined individual tumors. Their radiation doses were estimated by the hybrid method. This method employed the activity measured for each individual tumor by a single intratherapy SPECT scan, as well as the tumor's volume, to individually normalize the composite time-activity curve as appropriate. The individual normalization factors then converted the composite radiation dose to radiation doses for individual tumors. Reduction in tumor volume was calculated for both composite and individual tumors at 12 weeks posttherapy. RESULTS For 14 composite tumors in 10 patients, the median pretherapy volume was 170 cm 3 . Application of a sigmoidal curve function to the plot of volume reduction versus radiation absorbed dose resulted in degeneration of the curve into a straight line with a negative slope. There was no statistical significance in the relationship ( P = 0.73). For 43 individual tumors, the median pretherapy tumor volume was 26 cm 3 . The plot of volume reduction versus dose was fairly well fit by a sigmoidal curve, and the relationship approached statistical significance ( P = 0.06). The representation assigned 56% of the shrinkage to the effects of unlabeled tositumomab. For the subset of individual tumors with a pretherapy volume less than 10 cm 3 from 6 patients (n = 15), the relationship was significant ( P = 0.03). The sigmoidal representation assigned only 12% of the shrinkage to unlabeled tositumomab, as contrasted with 72% for tumors with pretherapy volume greater than 10 cm 3 . CONCLUSIONS For patients who attained a partial response, analysis of individual tumors by a hybrid dosimetric method led to a dependence between volume reduction at 12 weeks and radiation dose that tended to be significant. The same was not true with dosimetry of composite tumors based on pretherapy conjugate views alone. It appeared that volume reductions from both unlabeled antibody and radiation dose were important in tositumomab therapy of lymphoma patients, with unlabeled antibody relatively more important for larger tumors. Cancer 2002;94:1258–63. © 2002 American Cancer Society. DOI 10.1002/cncr.10294Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34359/1/10294_ftp.pd