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PURPOSE: Circulating tumor DNA in plasma may present a minimally invasive opportunity to identify tumor-derived mutations to inform selection of targeted therapies for individual patients, particularly in cases of oligometastatic disease where biopsy of multiple tumors is impractical. To assess the utility of plasma DNA as a “liquid biopsy” for precision oncology, we tested whether sequencing of plasma DNA is a reliable surrogate for sequencing of tumor DNA to identify targetable genetic alterations. METHODS: Blood and biopsies of 1–3 tumors were obtained from 4 evaluable patients with advanced breast cancer. One patient provided samples from an additional 7 tumors post-mortem. DNA extracted from plasma, tumor tissues, and buffy coat of blood were used for probe-directed capture of all exons in 149 cancer-related genes and massively parallel sequencing. Somatic mutations in DNA from plasma and tumors were identified by comparison to buffy coat DNA. RESULTS: Sequencing of plasma DNA identified 27.94 +/− 11.81% (mean +/− SD) of mutations detected in a tumor(s) from the same patient; such mutations tended to be present at high allelic frequency. The majority of mutations found in plasma DNA were not found in tumor samples. Mutations were also found in plasma that matched clinically undetectable tumors found post-mortem. CONCLUSIONS: The incomplete overlap of genetic alteration profiles of plasma and tumors warrants caution in the sole reliance of plasma DNA to identify therapeutically targetable alterations in patients, and indicates that analysis of plasma DNA complements, but does not replace, tumor DNA profiling. TRIAL REGISTRATION: Subjects were prospectively enrolled in trial NCT01836640 (registered April 22, 2013).

The purpose of this study was to identify the details of percutaneous catheter drainage (PCD) of pyogenic liver abscesses, the etiologic factors, and the management techniques that contribute to successful treatment.The records of 75 consecutively registered patients who underwent PCD of 96 abscesses at a single institution between May 2009 and May 2014 were retrospectively reviewed. Thirty-nine patients (52%) were oncology patients, and 36 (48%) had recently undergone abdominal surgery. Primary success was defined as abscess healing with the primary PCD intervention and 30-day postdrainage survival. Salvage success was defined as abscess healing with follow-up secondary PCD placement for symptomatic hepatic satellite collections or for clinical recurrence. Catheter adjustments were performed during follow-up to optimize existing drains. Univariate, multivariate, and general linear mixed model analyses were performed. The median follow-up time after catheter removal was 6 months (range, 2-62 months).Drains were primarily successful in 54 patients (72%), and 17 patients (23%) needed salvage PCD; thus, overall success was achieved in 71 patients (95%). The other four patients (5%) died of sepsis. The primary success rate was reduced in patients with unresectable malignancies (p = 0.01), multiple abscesses (p = 0.01), and output ≥ 15 mL/d at catheter endpoint (n = 7, p = 0.001). Only unresectable malignancies had slightly lower overall success. Large abscesses (150 cmPCD was effective first-line treatment of complicated pyogenic liver abscesses, which often require catheter adjustment and salvage drainage procedures to reliably achieve success.

Rationale and ObjectivesIn flipped learning, medical students independently learn facts and concepts outside the classroom, and then participate in interactive classes to learn to apply these facts. Although there are recent calls for medical education reform using flipped learning, little has been published on its effectiveness. Our study compares the effects of flipped learning to traditional didactic instruction on students' academic achievement, task value, and achievement emotions.Materials and MethodsAt three institutions, we alternated flipped learning with traditional didactic lectures during radiology clerkships, with 175 medical students completing a pretest on general diagnostic imaging knowledge to assess baseline cohort comparability. Following instruction, posttests and survey examinations of task value and achievement emotions were administered. Linear mixed effects analysis was used to examine the relationship between test scores and instruction type. Survey responses were modeled using ordinal category logistic regression. Instructor surveys were also collected.ResultsThere were no baseline differences in test scores. Mean posttest minus pretest scores were 10.5% higher in the flipped learning group than in the didactic instruction group (P = 0.013). Assessment of task value and achievement emotions showed greater task value, increased enjoyment, and decreased boredom with flipped learning (all P

Purpose Proper selection of imaging examinations and basic image interpretation skills are essential for all physicians, yet only approximately 25% of US medical schools require clerkships in radiology. Although there is limited time in most medical school curricula to allow the addition of a required radiology clerkship, the authors developed one that is vertically integrated over a two-year period. This clerkship includes one week of contact with radiologists distributed over the M2 and M3 years, podcasts, online modules, required readings, and presentations. A standard national examination is administered at the end of the clerkship period. This clerkship was designed to address the educational needs of students while occupying minimal time in the curriculum. The purpose of this study was to determine if students completing this clerkship perform as well on a national radiology examination as students from other medical schools, regardless of their curricula. Methods At the end of the M3 year, these students take a computer-based radiology examination developed by the Alliance of Medical Student Educators in Radiology and used by students at multiple medical schools nationally. The mean and median scores of these students were compared with those of students at these other institutions. Results The mean and median scores of the students were 74% and 74% (standard deviation, 7.5%) compared with 74% and 50% (standard deviation, 8.4%) at other institutions. Conclusions Students completing this vertically integrated radiology clerkship had test scores comparable with those of students at other medical schools.

Increasingly complex pediatric patients and improvements in technology warrant reevaluation of the risk associated with anesthesia for diagnostic imaging. Although magnetic resonance imaging is the imaging modality of choice for children given the potentially harmful effects of computerized tomography-associated ionizing radiation, we dare to suggest that certain patients would benefit from the liberalization of our current standard. Incorporating the use of newer computerized tomography technology may improve safety for those that are already at higher risk for adverse events. Furthermore, magnetic resonance imaging is not risk-free-what is often overlooked is the need for controlled ventilation and breath-holding to minimize motion artifact. As physicians at the forefront of the development and sustainability of the perioperative surgical home, anesthesiologists must work to not only optimize patients preoperatively but should also act as gatekeepers for procedural safety.

Associations between bronchioloalveolar carcinoma (BAC), mucinous differentiation, and epidermal growth factor receptor (EGFR) and KRAS mutations have been previously reported in studies of surgical specimens. We present the cytomorphology of lung adenocarcinomas, including metastases that were diagnosed by cytologic methods and the relationship to both EGFR and KRAS mutational status. We retrospectively reviewed the clinical and cytomorphologic features of 50 lung adenocarcinomas that were tested for both EGFR and KRAS mutations. Cytomorphologic features evaluated included cell size, architectural pattern, nucleoli, intranuclear cytoplasmic inclusions (INCI), mucin, necrosis, squamoid features, lymphocytic response, and histologic features of BAC differentiation. DNA was extracted from a paraffin-embedded cell block or frozen needle core fragments. Exon 19 deletions and the L858R mutation in exon 21 of EGFR were detected using PCR followed by capillary electrophoresis for fragment sizing. KRAS mutational analysis was performed by real-time PCR using a set of seven different Taqman(r) allelic discrimination assays to detect six mutations in codon 12 and one mutation in codon 13. Six cases (12%) showed EGFR mutations, 12 (24%) showed KRAS mutations, and 38 (62%) contained neither EGFR nor KRAS mutations. The majority of patients had stage IV disease (78%); 20 samples (40%) were from metastatic sites. The presence of prominent INCI (P = 0.036), papillary fragments (P = 0.041), and histologic features of BAC on paraffin block (P = 0.039) correlated with the presence of EGFR mutations. The presence of necrosis (P = 0.030), squamoid features (P = 0.048), and poorly differentiated tumors (P = 0.025) were more likely to be identified in the KRAS positive group.

Our aim was to determine which of three contrast-enhanced phases (early arterial, late arterial, or portal venous) was optimal for achieving maximal enhancement of the celiac artery, portal vein, and hepatic parenchyma. We also wanted to learn which phase provided the maximal tumor-to-parenchyma difference when using multidetector CT (MDCT) with fixed timing delays.Fifty-two patients with suspected or known hepatic tumors underwent multiphasic contrast-enhanced MDCT using double arterial (early and late arterial) and venous phase acquisitions with fixed timing delays. All patients were administered 150 mL of IV contrast material at an injection rate of 4 mL/sec. Images were acquired at 20 sec for the early arterial phase, 35 sec for the late arterial phase, and 60 sec for the portal venous phase. Attenuation measurements of the celiac artery, portal vein, normal hepatic parenchyma, and the hepatic tumor were compared. Three reviewers independently and subjectively rated tumor conspicuity for each of the three phases. Ratings were compared using kappa statistics.Late arterial phase images showed maximal celiac axis attenuation, whereas portal venous phase images revealed the highest portal vein and normal hepatic parenchymal attenuation. Maximal tumor-to-parenchyma differences for hypovascular tumors was superior in the portal venous phase, but we found no significant differences in maximal tumor-to-parenchyma differences for hypervascular tumors among the evaluated phases. On subjective analysis, interobserver agreement was moderate to very good for the three phases. All three reviewers graded both hypovascular and hypervascular tumor conspicuity as superior in either the late arterial phase or the portal venous phase in most patients. In only one patient was the early arterial phase graded as superior to the late arterial and portal venous phases (by two of the three reviewers).When MDCT of the liver is performed using fixed timing delays, maximal vascular and hepatic parenchymal enhancement is achieved on either late arterial phase or portal venous phase imaging. In most patients, early arterial phase imaging does not improve tumor conspicuity by either quantitative or subjective analysis.

In February 2010, our radiology department adopted the use of the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteria for newly diagnosed oncology patients. Prior to staff used RECIST 1.1, we hypothesized that education and feedback interventions could help clarify differences between RECIST 1.0 and the newly adopted RECIST 1.1 guidelines and result in appropriate and accurate utilization of both reporting systems. This study evaluates the effect of education and feedback interventions on the accuracy of computed tomography (CT) reporting using RECIST criteria.Consecutive CT scan reports and images were retrospectively reviewed during three different periods to assess for compliance and adherence to RECIST guidelines. Data collected included interpreting faculty, resident, type, and total number of errors per report. Significance testing of differences between cohorts was performed using an unequal variance t-test. Group 1 (baseline): RECIST 1.0 used; prior to adoption of RECIST 1.1 criteria. Group 2 (post distributed educational materials): Following adoption of RECIST 1.1 criteria and distribution of educational materials. Group 3 (post audit and feedback): Following the audit and feedback intervention.The percentage of reports with errors decreased from 30% (baseline) to 28% (group 2) to 22% (group 3). Only the difference in error rate between the baseline and group 3 was significant (P = .03).The combination of distributed educational materials and audit and feedback interventions improved the quality of radiology reports requiring RECIST criteria by reducing the number of studies with errors.

Totally implanted subcutaneous central venous access devices (chest ports) are an attractive option for patients in need of intermittent, recurrent venous access. In our department, these are placed by different operator types including interventional radiology (IR) attending physicians, dedicated IR nurse practitioners (NP), and IR fellows/radiology residents. The purpose of our study is to assess the rate of complications of subcutaneous chest port placement among the different operator types.A retrospective review of all subcutaneous central venous access devices implanted in our department between October 8, 2004, and October 19, 2007, was undertaken. Total numbers of port days, overall complication rates for all operators, as well as complication rates for the various operator types were calculated and were compared using the chi square test.A total of 558 patients had totally implanted subcutaneous central venous access devices placed during the period of study. Of these, 536 had documented follow-up and comprise the study population. A total of 89 were placed by attending physician alone, 133 by an NP, and 314 by an IR fellow or resident, with supervision by an attending physician. Mean duration of port usage was 341 days with 182,522 total port days. A total of 39 complications occurred (7.28%), including 27 infections (5%). There was no statistically significant difference in overall complication rates, including infection rates, among operator groups (P = .925).Our results confirm that well-trained physician extenders and trainees can safely perform chest port placement and that these providers, under appropriate supervision, can help provide improved access to chest port placement for patients and referring clinicians.

Conventional surgical technique of subcutaneous venous port placement describes dissection of the port pocket to the pectoralis fascia and suture fixation of the port to the fascia to prevent inversion of the device within the pocket. This investigation addresses the necessity of that step. Between October 8, 2004 and October 19, 2007, 558 subcutaneous chest ports were placed at our institution; 24 cases were excluded from this study. We performed a retrospective review of the remaining 534 ports, which were placed using standard surgical technique with the exception that none were sutured into the pocket. Mean duration of port use, total number of port days, indications for removal, and complications were recorded and compared with the literature. Mean duration of port use was 341 days (182,235 total port days, range 1–1279). One port inversion/flip occurred, which resulted in malfunction and necessitated port revision (0.2%). Other complications necessitating port removal included infection 26 (5%), thrombosis n = 2 (

Purpose This retrospective study evaluated tunneled catheter outcomes in patients aged 75 years and older undergoing hemodialysis. Materials and Methods Patients aged 75 years or older receiving hemodialysis comprised the study group. A control group of patients 40–60 years of age was randomly selected from the same dialysis quality assurance database. Demographic data, medical comorbidities, and catheter-specific data regarding indwelling time, function, interventions, and complications were recorded. Results Sixty-nine tunneled catheters were identified in 23 patients who comprised the study group (13 men and 10 women; mean age, 81.3 years; range, 75–88 y). The mean number of catheters per patient was three (range, 1–8). The mean indwelling time was 137.4 days (range, 2–622 d). Seventy-eight catheters were identified in the control group ( n = 29; 14 men and 15 women; mean age, 50.6 years; range, 41–59 y). The mean number of catheters per patient was 2.7 (range, 1–9). The mean indwelling time was 139.7 days (range, 1–994 d). There was no statistically significant difference in the mean number of catheters per patient ( P = .83) or the mean indwelling time ( P = .93) between the two groups. There was no significant difference between the two groups in the indications for catheter removal or exchange: infection ( P = 1.0), catheter no longer needed ( P = 1.0), and physical catheter malfunction ( P = .48). The calculated infection rates in the elderly patient and younger control groups were 0.30 per 100 catheter-days and 0.26 per 100 catheter-days, respectively. Conclusions Tunneled catheter outcomes in patients aged 75 years and older undergoing hemodialysis do not vary significantly compared with those in a younger cohort.

To determine the optimal phase for enhancement of the normal pancreas and peripancreatic vasculature and the maximal tumor-to-pancreatic parenchymal enhancement difference by using multiphase, contrast material-enhanced, multi-detector row helical computed tomography (CT).Forty-nine patients with a normal-appearing pancreas but suspected of having pancreatic abnormality and 28 patients with proved pancreatic adenocarcinoma underwent multiphase, contrast-enhanced, multi-detector row CT during the arterial phase (AP), pancreatic parenchymal phase (PPP), and portal venous phase (PVP). Attenuation values of the normal pancreas, pancreatic adenocarcinoma, celiac and superior mesenteric arteries, and superior mesenteric and portal veins were measured during all three imaging phases. Quantitative analysis of these measurements and subjective qualitative analysis of tumor conspicuity were performed.Maximal enhancement of the normal pancreatic parenchyma occurred during the PPP. Maximal tumor-to-parenchyma attenuation differences during the PPP and PVP were equivalent but greater than that during the AP. Subjective analysis revealed that tumor conspicuity during the PPP and PVP was equivalent but superior to that during the AP. Maximal arterial enhancement was seen during the PPP, and maximal venous enhancement was seen during the PVP.A combination of PPP and PVP imaging is sufficient for detection of pancreatic adenocarcinoma, because it provides maximal pancreatic parenchymal and peripancreatic vascular enhancement. AP imaging can be reserved for patients in whom CT angiography is required.