Giles W. Boland

Incidental Adrenal Lesions: Principles, Techniques, and Algorithms for Imaging Characterization

Incidental adrenal lesions are commonly detected at computed tomography, and lesion characterization is critical, particularly in the oncologic patient. Imaging tests have been developed that can accurately differentiate these lesions by using a variety of principles and techniques, and each is discussed in turn. An imaging algorithm is provided to guide radiologists toward the appropriate test to make the correct diagnosis.

Characterization of Adrenal Masses by Using FDG PET: A Systematic Review and Meta-Analysis of Diagnostic Test Performance

PURPOSE To perform a systematic review and meta-analysis of published data to determine the diagnostic utility of adrenal fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) for distinguishing benign from malignant adrenal disease. MATERIALS AND METHODS Data on FDG PET assessment in MEDLINE and other electronic databases (from inception to November 2009) and in subject matter-specific journals were evaluated and compared with histologic diagnoses and/or established clinical and imaging follow-up results. Methodologic quality was assessed by using Quality Assessment of Diagnostic Accuracy Studies criteria. Bivariate random-effects meta-analytical methods were used to estimate summary and subgroup-specific sensitivity, specificity, and receiver operating characteristic curves and to investigate the effects of study design characteristics and imaging procedure elements on diagnostic accuracy. RESULTS A total of 1391 lesions (824 benign, 567 malignant) in 1217 patients from 21 eligible studies were evaluated. Qualitative (visual) analysis of 841 lesions (in 14 reports) and quantitative analyses based on standardized uptake values (SUVs) for 824 lesions (in 13 reports) and standardized uptake ratios (SURs) for 562 lesions (in eight reports) were performed. Resultant data were highly heterogeneous, with a model-based inconsistency index of 88% (95% confidence interval [CI]: 79%, 98%). Mean sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio values for differentiating between benign and malignant adrenal disease were 0.97 (95% CI: 0.93, 0.98), 0.91 (95% CI: 0.87, 0.94), 11.1 (95% CI: 7.5, 16.3), 0.04 (95% CI: 0.02, 0.08), and 294 (95% CI: 107, 805), respectively, with no significant differences in accuracy among the visual, SUV, and SUR analyses. CONCLUSION Meta-analysis of combination PET-computed tomography (CT) reports revealed that FDG PET was highly sensitive and specific for differentiating malignant from benign adrenal disease. Diagnostic accuracy was not influenced by the type of imaging device (PET vs PET/CT), but specificity was dependent on the clinical status (cancer vs no cancer).

PET/CT for the Characterization of Adrenal Masses in Patients with Cancer: Qualitative Versus Quantitative Accuracy in 150 Consecutive Patients

OBJECTIVE The objective of our study was to evaluate a large cohort of patients with PET/CT to determine whether qualitative (visual) assessment, quantitative standardized uptake value (SUV), or standardized uptake ratio (SUR) techniques should be used when attempting to characterize adrenal masses in patients with cancer. MATERIALS AND METHODS The study group was composed of 150 consecutive patients (78 men, 72 women; mean age, 60 years; range, 24-88 years) with documented adrenal lesions. All patients were known to have an underlying primary malignancy and were referred for PET/CT to evaluate the underlying primary and metastatic tumor burden. Definitive lesion characterization was determined by evaluating all histologic adrenal specimens and all relevant prior and follow-up CT scans, including unenhanced, contrast-enhanced, and delayed contrast-enhanced washout studies. RESULTS Of the 139 benign lesions, 109 were considered benign by CT densitometry measurements and 135 by qualitative PET data. Qualitative PET characterized 28 of 30 benign lesions that were considered indeterminate by unenhanced CT. All 26 malignant lesions were characterized by PET: All showed qualitative and quantitative signal intensity greater than the liver. By combining unenhanced and qualitative CT data with the retrospective PET data, the analysis yielded a sensitivity of 100% for the detection of malignancy, a specificity of 99%, a positive predictive value (PPV) of 93%, a negative predictive value (NPV) of 100%, and an accuracy of 99% (Table 1). Conversely, for the detection of benignity, the sensitivity, specificity, PPV, NPV, and accuracy were 99%, 100%, 100%, 93%, and 99%, respectively. CONCLUSION PET/CT is a highly accurate method for differentiating benign from malignant adrenal masses particularly when using qualitative, rather than quantitative, PET data. The routine use of quantitative mean or maximal SUV or SUR data may be unnecessary. Occasional benign lesions do show mild to moderate increased FDG uptake compared with that of the liver and may mimic some malignant lesions. Without evidence that these lesions are benign by unenhanced CT densitometry or adrenal mass stability or growth from previous CT scans, we recommend that these lesions be characterized using contrast-enhanced washout tests and that if those tests are inconclusive, using percutaneous biopsy if early lesion characterization is mandatory.

Radiology of pancreatic adenocarcinoma: Current status of imaging

Pancreatic adenocarcinoma is one of the leading causes of cancer death in the West, with a poor overall 5‐year survival rate of only 4%. Late clinical presentation with an advanced disease results in a low rate of surgical intervention. Tumor serum marker CA 19‐9 is sensitive, although not specific for the diagnosis of adenocarcinomas of the pancreas. The treatment approach is based on whether the tumor is resectable or non‐resectable at presentation. Therefore, imaging plays a crucial role in the management of this disease. Many modalities are available to image the pancreas. They include non‐invasive techniques, like ultrasound, contrast‐enhanced multidetector computed tomography, magnetic resonance imaging and integrated positron emission tomography/computed tomography, and invasive techniques, like endoscopic retrograde cholangiopancreatography and endoscopic ultrasound. Each of these modalities has its peculiar strengths and weaknesses.

Recommendations for additional imaging in radiology reports: multifactorial analysis of 5.9 million examinations.

PURPOSE To quantify the rates of recommendation for additional imaging (RAI) in a large number of radiology reports of different modalities and to estimate the effects of 11 clinically relevant factors. MATERIALS AND METHODS This HIPAA compliant research was approved by the institutional review board under an expedited protocol for analyzing anonymous aggregated radiology data. All diagnostic imaging examinations (n = 5 948 342) interpreted by radiologists between 1995 and 2008 were studied. A natural language processing technique specifically designed to extract information about any recommendations from radiology report texts was used. The analytic data set included three quantitative variables: the interpreting radiologists experience, the year of study, and patient age. Categoric variables described patient location (inpatient, outpatient, emergency department), whether a resident dictated the case, patient sex, modality, body area studied, ordering service, radiologists specialty division, and whether the examination result was positive. A multivariable logistic regression model was used to determine the effect of each of these factors on likelihood of RAI while holding all others equal. RESULTS Recommendations increased during the 13 years of study, with the unadjusted rate rising from roughly 6% to 12%. After accounting for all other factors, the odds of any one examination resulting in an RAI increased by 2.16 times (95% confidence interval: 2.12, 2.21) from 1995 to 2008. As radiologist experience increased, the odds of an RAI decreased by about 15% per decade. Studies that had positive findings were more likely (odds ratio = 5.03; 95% confidence interval: 4.98, 5.07) to have an RAI. The remaining factors also had significant effects on the tendency for an RAI. CONCLUSION The likelihood of RAI increased by 15% for each decade of radiologist experience and roughly doubled over 13 years of study.

Postoperative Imaging in Liver Transplantation: What Radiologists Should Know

Liver transplantation is now frequently used in the treatment of end-stage liver disease. Therefore, it is important that radiologists be aware of common anastomotic techniques and expected postoperative imaging findings. Imaging is most useful in evaluating for posttransplantation complications, which are broadly classified into vascular, biliary, and other complications. Hepatic artery thrombosis is the most significant complication and is often associated with graft failure. Radiologists have multiple modalities at their disposal for optimal evaluation. Doppler ultrasonography (US) is the preliminary imaging modality for gross evaluation of the liver parenchyma, biliary tree, and vasculature for abnormalities. When US findings are indeterminate or there is persistent clinical suspicion for an abnormality, computed tomography (CT) is often performed. The major indications for CT are detection of bile leak, hemorrhage, and abscess, but CT is also useful in the assessment of the vasculature. T-tube cholangiography and magnetic resonance cholangiopancreatography are the best noninvasive imaging tools for evaluating for biliary stricture. Some investigators would argue that endoscopic retrograde cholangiopancreatography (ERCP) is a better diagnostic imaging modality; however, ERCP is invasive. Hepatobiliary scintigraphy is optimal for the evaluation of biliary leakage. Early detection of posttransplantation complications will help lower morbidity rates and will likely allow graft salvage in selected cases.

Imaging of acute right lower abdominal quadrant pain.

This article reviews the clinical diagnosis of appendicitis, indications and options for appendiceal imaging, compares appendiceal CT techniques, and describes the imaging findings with appendicitis and alternative conditions that can clinically mimic appendicitis.

Incidental Adrenal Lesions: Accuracy of Characterization with Contrast-enhanced Washout Multidetector CT—10-minute Delayed Imaging Protocol Revisited in a Large Patient Cohort

PURPOSE To reassess the accuracy of the 10-minute delayed scan to differentiate both lipid-rich and lipid-poor lesions in a large cohort of patients. MATERIALS AND METHODS This HIPAA-compliant retrospective study had institutional review board approval; the need for informed consent was waived. A multidetector computed tomography (CT) adrenal protocol (unenhanced, dynamic contrast material-enhanced, and 10-minute delayed CT) was used in 314 consecutive patients (201 women, 113 men; mean age, 63.6 years) for the period from January 2006 through February 2009. The mean adrenal attenuation during all three CT phases was measured by two readers, and the relative percentage washout (RPW) and absolute percentage washout (APW) values were calculated. APW and RPW receiver operating characteristic (ROC) analysis was performed to evaluate the strength of the tests. RESULTS There were 323 adrenal lesions (213 left, 110 right) consisting of 307 adenomas and 16 nonadenomas. The sensitivity, specificity, and accuracy for the RPW test at a washout threshold of 50% were 55.7%, 100%, and 57.9%, respectively; at 40% were 76.9%, 93.7%, and 77.7%; and at 35% were 81.4%, 93.7%, and 82.0%. The sensitivity, specificity, and accuracy for the APW test at a 60% threshold were 52.1%, 93.3%, and 54.0%, respectively; at 55% were 62.5%, 93.3%, and 64.0%; and at 50% were 71.3%, 80.0%, and 71.7%. Areas under the ROC curve were 0.85 (95% confidence interval: 0.75, 0.95) and 0.91 (95% confidence interval: 0.85, 0.97) for the APW and RPW tests, respectively, to detect adenomatous disease. CONCLUSION The 10-minute delayed adrenal enhancement washout test has reduced sensitivity for the characterization of adrenal adenomas compared with results from prior studies.

Pixantrone dimaleate versus other chemotherapeutic agents as a single-agent salvage treatment in patients with relapsed or refractory aggressive non-Hodgkin lymphoma: a phase 3, multicentre, open-label, randomised trial

BACKGROUND Pixantrone dimaleate (pixantrone)--a novel aza-anthracenedione--was synthesised to reduce anthracycline-related cardiotoxicity without compromising antitumour efficacy. We aimed to assess the efficacy and safety of pixantrone versus an investigators choice of a single-agent therapy in heavily pretreated patients with relapsed or refractory aggressive non-Hodgkin lymphoma. METHODS In this phase 3, multicentre, open-label, randomised trial at 66 hospitals in Europe, India, Russia, South America, the UK, and the USA, patients with histologically confirmed aggressive non-Hodgkin lymphoma who had relapsed after two or more previous chemotherapy regimens were randomly assigned (1:1) by an interactive voice response system to treatment with pixantrone dimaleate (85 mg/m(2) intravenously on days 1, 8, and 15 of a 28-day cycle, for up to six cycles) or to a comparator (vinorelbine, oxaliplatin, ifosfamide, etoposide, mitoxantrone, or gemcitabine) given at prespecified standard doses and schedules. Patients were stratified by region, International Prognostic Index score, and previous stem-cell transplantation. Patients and investigators were not masked to treatment assignment; however, an independent assessment panel was masked. The primary endpoint was the proportion of patients with a complete or unconfirmed complete response in the intention-to-treat (ITT) population at the end of treatment. Primary analyses of efficacy were based on the independent assessment panels data review. The study is registered at ClinicalTrials.gov, number NCT00088530. FINDINGS The ITT population comprised 70 patients randomly assigned to the pixantrone group and 70 to the comparator. Five patients (two in the pixantrone group and three in the comparator group) dropped out before receiving their study drug. 14 patients (20·0% [95% CI 11·4-31·3]) who received pixantrone achieved a complete or unconfirmed complete response at end of treatment compared with four patients (5·7% [1·6-14·0]) in the comparator group (p = 0·021). The most common grade 3 or 4 adverse events in patients given pixantrone were uncomplicated, non-cumulative neutropenia (28 [41·2%] of 68 patients vs 13 [19·4%] of 67 patients in the comparator group), leucopenia (16 [23·5%] vs five [7·5%]), and thrombocytopenia (eight [11·8%] vs seven [10·4%]). INTERPRETATION Pixantrone, given as a single-agent salvage therapy in heavily pretreated patients with relapsed or refractory aggressive non-Hodgkin lymphoma, is efficacious and tolerable. It could be a treatment option for patients whose aggressive non-Hodgkin lymphoma has failed to respond to at least two previous chemotherapy regimens. FUNDING Cell Therapeutics, Inc.

Prognostic indicators in acute pancreatitis: CT vs APACHE II

PURPOSE To investigate the correlation between established contrast-enhanced computed tomography (CECT) criteria of disease severity in acute pancreatitis and the APACHE (Acute Physiology and Chronic Health Evaluation) II score and to assess the utility of each as prognostic indicators in acute pancreatitis. MATERIALS AND METHODS Over a 1-year period, prospective, consensus interpretation of the CECTs of 35 consecutive inpatients was performed with determination of the CECT grade, degree of necrosis, and severity index. The APACHE II score was calculated within 24 h of CECT. Multiple clinical endpoints were recorded: local complications (pseudocyst, abscess, or acute fluid collections requiring urgent surgical or radiological intervention), systemic disease (intensive care unit admission), and duration of hospitalization. Statistical analysis was performed to determine correlations. RESULTS No statistically significant correlation existed between the APACHE II score and CECT grade, the degree of necrosis, or the CECT severity index. Only the CECT grade and severity index correlated significantly with the occurrence of local complications (P = 0.0035 and 0.0048, respectively). The APACHE II score was superior to the CECT grade as a predictor of the need for ICU admission (P = 0.022 vs P = 0.035), and no other CECT criteria was a significant predictor of ICU admission. CONCLUSION The preferred clinical and imaging prognostic measures in acute pancreatitis, the APACHE II score and CECT criteria, do not correlate with one another in the commonly encountered, mixed primary and tertiary care population. The mathematical integration of CECT criteria and the APACHE II score fails to yield a predictor of outcome superior to the use of any one measure alone. CECT criteria best define local anatomic abnormality, and are superior to the APACHE II score as predictors of local complications. The APACHE II score is superior to all CECT criteria as an indicator of systemic disease severity (reflected in the need for ICU admission). The most effective initial triage would be immediate APACHE II calculation. Further use of imaging vs clinical assessment can then be individualized.