Celebrating a legacy, reflecting on the present, and safeguarding our future.

OBJECTIVE: During the 20th century, radiologists enjoyed relationships with clinicians and patients through daily face-to-face communication. As specialist consultants, radiologists were naturally integral members of the care team. CONCLUSION: The widespread availability of information technology, notably PACS, has disrupted the fundamental radiologist-clinician axis. New generations of radiologists must respond to this disturbing trend by (re)learning how to "add value" by rekindling personal professional relationships, developing global leadership skills, and becoming involved in health care system design and implementation.

DiffusionCT: Latent Diffusion Model for CT Image Standardization.

Computed tomography (CT) is one of the modalities for effective lung cancer screening, diagnosis, treatment, and prognosis. The features extracted from CT images are now used to quantify spatial and temporal variations in tumors. However, CT images obtained from various scanners with customized acquisition protocols may introduce considerable variations in texture features, even for the same patient. This presents a fundamental challenge to downstream studies that require consistent and reliable feature analysis. Existing CT image harmonization models rely on GAN-based supervised or semi-supervised learning, with limited performance. This work addresses the issue of CT image harmonization using a new diffusion-based model, named DiffusionCT, to standardize CT images acquired from different vendors and protocols. DiffusionCT operates in the latent space by mapping a latent non-standard distribution into a standard one. DiffusionCT incorporates a U-Net-based encoder-decoder, augmented by a diffusion model integrated into the bottleneck part. The model is designed in two training phases. The encoder-decoder is first trained, without embedding the diffusion model, to learn the latent representation of the input data. The latent diffusion model is then trained in the next training phase while fixing the encoder-decoder. Finally, the decoder synthesizes a standardized image with the transformed latent representation. The experimental results demonstrate a significant improvement in the performance of the standardization task using DiffusionCT.

A Guide to Expanding the Use of Buprenorphine Beyond Standard Initiations for Opioid Use Disorder.

Buprenorphine has become an important medication in the context of the ongoing opioid epidemic. However, complex pharmacologic properties and varying government regulations create barriers to its use. This narrative review is intended to facilitate buprenorphine use-including non-traditional initiation methods-by providers ranging from primary care providers to addiction specialists. This article briefly discusses the opioid epidemic and the diagnosis and treatment of opioid use disorder (OUD). We then describe the basic and complex pharmacologic properties of buprenorphine, linking these properties to their clinical implications. We guide readers through the process of initiating buprenorphine in patients using full agonist opioids. As there is no single recommended approach for buprenorphine initiation, we discuss the details, advantages, and disadvantages of the standard, low-dose, bridging-strategy, and naloxone-facilitated initiation techniques. We consider the pharmacology of, and evidence base for, buprenorphine in the treatment of pain, in both OUD and non-OUD patients. Throughout, we address the use of buprenorphine in children and adolescent patients, and we finish with considerations related to the settings of pregnancy and breastfeeding.

Comparative real-world survival outcomes of metastatic papillary and clear cell renal cell carcinoma treated with immunotherapy, targeted therapy, and combination therapy.

INTRODUCTION: While there are a plethora of studies supporting novel treatment approaches in metastatic clear cell renal cell carcinoma (ccRCC), much of the data used to inform care of patients with metastatic papillary RCC (pRCC) is extrapolated from ccRCC. Several recent phase III trials have supported the use of immunotherapy (IO) and targeted therapy (TT)+IO in ccRCC, without corresponding data for pRCC. Using ccRCC as a comparison group, we sought to describe real-world trends in the utilization of systemic therapy and its impact on overall survival (OS) among patients with metastatic pRCC. METHODS: Using the National Cancer Database (NCDB), we identified cases of metastatic pRCC and ccRCC between 2015 and 2018. Patients were stratified into groups based on histology and first-line treatments (TT, IO, TT + IO). Differences in baseline characteristics were assessed using the Kruskal-Wallis test for continuous variables, and the Chi-square or Fisher's exact test for categorical variables. Survival analysis was performed using Kaplan-Meier estimates and multivariable Cox regression analyses. RESULTS: A total of 6,920 patients with a diagnosis of metastatic RCC were identified: 594 (8.6%) with pRCC and 6,326 (91.4%) with ccRCC. Overall, 4,710 patients received TT (455 pRCC and 4,255 ccRCC), 1,585 received IO (77 pRCC and 1,508 ccRCC), and 625 received TT+IO (62 pRCC and 563 ccRCC). Temporal trend between 2015 and 2018 revealed an increased utilization of IO and TT + IO for pRCC and ccRCC. In patients with metastatic pRCC, neither IO (HR 1.03; 95% CI 0.75-1.42) nor TT+IO (HR 0.90, 95% CI 0.63-1.28) were associated with better OS compared to TT alone. In contrast, both IO and combination TT and IO were associated with significantly better OS than TT for patients with metastatic ccRCC (IO group: hazard ratio [HR] 0.75, 95% confidence interval [CI] 0.68-0.82; TT+IO group: HR 0.82, 95% CI 0.72-0.93). Cytoreductive nephrectomy was associated with better OS in both pRCC (HR 0.59, 95% CI 0.46-0.77) and ccRCC (HR 0.54, 95% CI 0.50-0.58). CONCLUSIONS: Although IO and TT + IO were associated with better OS among patients with metastatic ccRCC, this same effect was not observed among patients with pRCC.

Validating the association of adverse pathology with distant metastasis and prostate cancer mortality 20-years after radical prostatectomy.

PURPOSE: To assess the association of adverse pathology (AP), defined as high-grade (≥ Gleason Grade Group 3) and/or non-organ confined disease, with long-term oncologic outcomes after radical prostatectomy (RP). MATERIALS AND METHODS: Using a stratified cohort sampling design, we evaluated the association of AP with the risk of distant metastasis (DM) and prostate cancer-specific mortality (PCSM) up to 20 years after RP in 428 patients treated between 1987 to 2004. Cox regression of cause-specific hazards was used to estimate the absolute risk of both endpoints, with death from other causes treated as a competing risk. Additionally, subgroup analysis in patients with low and/or intermediate-risk disease, who are potentially eligible for active surveillance (AS), was performed. RESULTS: Within the cohort sample, 53% of men exhibited AP at time of RP, with median follow up of 15.5 years (IQR 14.6-16.6 years) thereafter. Adverse pathology was highly associated with DM and PCSM in the overall cohort (HR 12.30, 95% confidence interval [CI] 5.30-28.55, and HR 10.03, 95% CI 3.42-29.47, respectively, both P < 0.001). Adverse pathology was also highly associated with DM and PCSM in the low/intermediate-risk subgroup (HR 10.48, 95% CI 4.18-26.28, and 8.60, 95% CI 2.40-30.48, respectively, both P < 0.001). CONCLUSIONS: Adverse pathology at the time of RP is highly associated with future development of DM and PCSM. Accurate prediction of AP may thus be useful for individualizing risk-based surveillance and treatment strategies.

GPS Assay Association With Long-Term Cancer Outcomes: Twenty-Year Risk of Distant Metastasis and Prostate Cancer-Specific Mortality.

PURPOSE: To assess the association between the Oncotype DX Genomic Prostate Score (GPS) result and long-term oncological outcomes following radical prostatectomy (RP). METHODS: We evaluated the association of the GPS result assayed from the index lesion from RP tissue with the risk of distant metastases (DM) and prostate cancer-specific mortality (PCSM) over the 20 years following RP in a stratified cohort sample of 428 patients from 2,641 treated between 1987 and 2004. Cox regression of cause-specific hazards was used to estimate the absolute risk of both end points, with death from other causes treated as a competing risk. A correction for regression to the mean (RM) was applied since the GPS test was developed using this cohort. Exploratory analysis using presurgical parameters and the GPS test as prognostic variables was performed to assess the additional value of the GPS test on 20-year risk of DM and PCSM. Model discrimination was measured using the area under the receiver operating characteristic curve. RESULTS: The GPS test appears to be independently associated with both 20-year risk of DM and PCSM with a low false discovery rate. Per 20-unit increase in GPS, multivariable analysis with RM correction estimated hazard ratios of 2.24 (95% CI, 1.49 to 3.53) and 2.30 (95% CI, 1.45 to 4.36) for DM and PCSM, respectively. Accuracy of models including clinical risk factors alone appeared to improve when including the GPS test in assessing risk of both end points. CONCLUSION: The results suggest that the GPS test provides information on the risk for the meaningful long-term outcomes of DM and PCSM.

Leveraging Non-lattice Subgraphs to Audit Hierarchical Relations in NCI Thesaurus.

Auditing National Cancer Institute (NCI) thesaurus is essential to ensure that it provides accurate terminology for cancer-related clinical care as well as translational and basic research. We leverage a structural-lexical approach to identify missing hierarchical IS-A relations in NCI thesaurus based on non-lattice subgraphs and derived lexical attributes of concepts. For each concept in a non-lattice subgraph, we use two ways to derive the concept's lexical attributes: (1) inheriting lexical attributes from its ancestors within the subgraph; and (2) inheriting lexical attributes from all its ancestors. For a pair of concepts not having a hierarchical relation, if the lexical attributes of one concept is a subset of that of the other, we suggest there is a potential missing IS-A relation between the two concepts. Our approach identified 547 non-lattice subgraphs in the 19.01d release of NCI thesaurus which revealed a total of 1,022 unique potential missing IS-A relations. A random sample of 100 relations was evaluated by a domain expert. Among these relations, 90 can be obtained by the way of inheriting lexical attributes from ancestors within non-lattice subgraph, among which 76 were confirmed as valid (a precision of 84.44%); and 82 can be obtained by the way of inheriting all ancestors, among which 73 were confirmed as valid (a precision of 89.02%). The results show that our structural-lexical approach based on non-lattice subgraphs is effective for auditing NCI thesaurus.

The Role of Imaging in the Diagnosis, Staging, Response to Treatment, and Surveillance of Patients with Germ Cell Tumors of the Testis.

Germ cell tumors (GCTs) of the testis are cured with the successful integration of surgery, chemotherapy, and/or radiation therapy in most cases. The favorable results are a consequence of improved risk stratification, risk-adapted chemotherapy, reduced morbidity of treatment, and appropriate integration of multimodal therapy. The success of these approaches depends on accurate staging with imaging studies of the testis, retroperitoneum, and thorax. This article reviews the indications for imaging and performance characteristics of modalities in the diagnosis, staging, surveillance, and follow-up of patients with GCTs. We also highlight the current guideline recommendations for imaging in treatment of patients with GCTs.

CT findings in acute myocarditis: 2 cases.

Myocarditis is a serious and life-threatening illness, which can pose a significant diagnostic dilemma at presentation. We report 2 patients with clinical myocarditis who had distinctive findings at coronary computed tomography. Both patients demonstrated delayed myocardial enhancement with iodinated contrast. The morphologic features of the enhancement were similar to the myocardial enhancement with gadolinium contrast on magnetic resonance imaging recently described in patients with myocarditis, and different from the enhancement patterns seen in patients with myocardial infarction. These findings are not previously reported in the literature. As computed tomography is more widely available for use in the acute setting than magnetic resonance imaging, these findings may have significant clinical utility and warrant further investigation.

Quality Assurance of NCI Thesaurus by Mining Structural-Lexical Patterns.

Quality assurance of biomedical terminologies such as the National Cancer Institute (NCI) Thesaurus is an essential part of the terminology management lifecycle. We investigate a structural-lexical approach based on non-lattice subgraphs to automatically identify missing hierarchical relations and missing concepts in the NCI Thesaurus. We mine six structural-lexical patterns exhibiting in non-lattice subgraphs: containment, union, intersection, union-intersection, inference-contradiction, and inference union. Each pattern indicates a potential specific type of error and suggests a potential type of remediation. We found 809 non-lattice subgraphs with these patterns in the NCI Thesaurus (version 16.12d). Domain experts evaluated a random sample of 50 small non-lattice subgraphs, of which 33 were confirmed to contain errors and make correct suggestions (33/50 = 66%). Of the 25 evaluated subgraphs revealing multiple patterns, 22 were verified correct (22/25 = 88%). This shows the effectiveness of our structurallexical-pattern-based approach in detecting errors and suggesting remediations in the NCI Thesaurus.

A potential role of ECG-gated CT for the diagnosis of pulmonary vein thrombus: an illustrative case report.

The presence of tumor thrombus in patients with lung cancer confers a risk of stroke and other end-organ ischemic events. This case highlights a potential role for electrocardiogram (ECG)-gated computed tomography (CT) in the diagnosis of this pathologic process. In this case, pulmonary vein thrombus was definitively identified by an ECG-CT following discordant results between CT and transthoracic echocardiogram. In addition, this case demonstrates how management decisions are affected by physician accessibility to and familiarity with specific imaging tests.

Identification of Coronary Artery Calcification and Diagnosis of Coronary Artery Disease by Abdominal CT: A Resident Education Continuous Quality Improvement Project.

RATIONALE AND OBJECTIVES: Coronary artery calcium (CAC) scoring is an excellent imaging tool for subclinical atherosclerosis detection and risk stratification. We hypothesize that although CAC has been underreported in the past on computed tomography (CT) scans of the abdomen, specialized resident educational intervention can improve on this underreporting. MATERIALS AND METHODS: Beginning July 2009, a dedicated radiology resident cardiac imaging rotation and curriculum was initiated. A retrospective review of the first 500 abdominal CT reports from January 2009, 2011, and 2013 was performed including studies originally interpreted by a resident and primary attending physician interpretations. Each scan was reevaluated for presence or absence of CAC and coronary artery disease (CAD) by a cardiovascular CT expert reader. These data were then correlated to determine if the presence of CAC had been properly reported initially. The results of the three time periods were compared to assess for improved rates of CAC and CAD reporting after initiation of a resident cardiac imaging curriculum. RESULTS: Statistically significant improvements in the reporting of CAC and CAD on CT scans of the abdomen occurred after the initiation of formal resident cardiac imaging training which included two rotations (4 weeks each) of dedicated cardiac CT and cardiac magnetic resonance imaging interpretation during the resident's second, third, or fourth radiology training years. The improvement was persistent and increased over time, improving from 1% to 72% after 2 years and to 90% after 4 years. CONCLUSIONS: This single-center retrospective analysis shows association between implementation of formal cardiac imaging training into radiology resident education and improved CAC detection and CAD reporting on abdominal CT scans.

Medical education and the tyranny of competency.

Those who educate medical students and physicians work in a world suffused with the concept of competency. This article examines the intellectual origins and hidden assumptions of this concept and argues that it is an inadequate, and even harmful, concept to use as a guiding motif for professional education. The competency model-which tends to be top-down and prescriptive-does not provide the framework for objective educational assessment that it claims to provide. The alternative apprenticeship model is more appropriate for professional education and is more consistent with what psychological research has shown about the acquisition of expertise.

Reproducibility and validity of lung density measures from cardiac CT Scans--The Multi-Ethnic Study of Atherosclerosis (MESA) Lung Study.

RATIONALE AND OBJECTIVES: Cardiac computed tomographic (CT) scans for the assessment of coronary calcium scores include approximately 70% of the lung volume and may be useful for the quantitative assessment of emphysema. The reproducibility of lung density measures from cardiac computed tomography and their validity compared to lung density measures from full-lung scans is unknown. MATERIALS AND METHODS: The Multi-Ethnic Study of Atherosclerosis (MESA) performed paired cardiac CT scans for 6814 participants at baseline and at follow-up. The MESA-Lung Study assessed lung density measures in the lung fields of these cardiac scans, counting voxels below -910 HU as moderate-to-severe emphysema-like lung regions. We evaluated: 1) the reproducibility of lung density measures among 120 randomly selected participants; 2) the comparability of measures acquired on electron beam CT (EBCT) and multidetector CT (MDCT) scanners among 10 participants; and 3) the validity of these measures compared to full-lung scans among 42 participants. Limits of agreement were determined using Bland-Altman approaches. RESULTS: Percent emphysema measures from paired cardiac scans were highly correlated (r = 0.92-0.95) with mean difference of -0.05% (95% limits of agreement: -8.3, 8.4%). Measures from EBCT and MDCT scanners were comparable (mean difference -0.9%; 95% limits of agreement: -5.1, 3.3%). Percent emphysema measures from MDCT cardiac and MDCT full-lung scans were highly correlated (r = 0.93) and demonstrated reasonable agreement (mean difference 2.2%; 95% limits of agreement: -9.2, 13.8%). CONCLUSIONS: Although full-lung imaging is preferred for the quantification of emphysema, the lung imaging from paired cardiac computed tomography provided a reproducible and valid quantitative assessment of emphysema in a population-based sample.

Transbronchial needle aspiration in diagnosing and staging lung cancer: how many aspirates are needed?

Transbronchial needle aspiration has emerged as a key technique for sampling mediastinal adenopathy but variable yields are reported. To determine the number of aspirates needed to optimize yield, we prospectively studied transbronchial needle aspiration and the sequential effect of each successive specimen on diagnostic yield in 79 patients with known or suspected lung carcinoma and mediastinal adenopathy. A total of 451 aspirates were performed in 79 patients (mean, 5.7 aspirates per patient; range, 2-13) with 45 cases (57%) positive for malignancy. A cytologically positive transbronchial needle aspiration occurred with the first aspirate in 42% of patients in whom this procedure established mediastinal nodal involvement. All positive results were achieved with seven or fewer aspirates. Similar yields were obtained for small cell and non-small cell lung cancer after seven aspirates. Rapid on-site specimen cytologic evaluation was used in 55 of 79 cases (70%), with a positive diagnosis obtained in 39 of 55 cases (71%) with on-site evaluation compared with six of 24 cases (25%) performed without on-site evaluation. The data suggest there is a plateau in yield after seven transbronchial needle aspirates, which may be sufficient to obtain an optimal yield in assessing patients with lung cancer and mediastinal adenopathy.