Taboo language across the globe: A multi-lab study.

The use of taboo words represents one of the most common and arguably universal linguistic behaviors, fulfilling a wide range of psychological and social functions. However, in the scientific literature, taboo language is poorly characterized, and how it is realized in different languages and populations remains largely unexplored. Here we provide a database of taboo words, collected from different linguistic communities (Study 1, N = 1046), along with their speaker-centered semantic characterization (Study 2, N = 455 for each of six rating dimensions), covering 13 languages and 17 countries from all five permanently inhabited continents. Our results show that, in all languages, taboo words are mainly characterized by extremely low valence and high arousal, and very low written frequency. However, a significant amount of cross-country variability in words' tabooness and offensiveness proves the importance of community-specific sociocultural knowledge in the study of taboo language.

Concordance of MRI With Pathology for Primary Staging of Rectal Cancer in Routine Clinical Practice: A Single Institution Experience.

PURPOSE: MRI is the preferred imaging modality for primary staging of rectal cancer, used to guide treatment. Patients identified with clinical stage I disease receive upfront surgical resection; those with clinical stage II or greater undergo upfront neoadjuvant therapy. Although clinical under-/over-staging may have consequences for patients and presents opportunities for organ preservation, the correlation between clinical and pathologic staging in routine clinical practice within a single institute has not been fully established. METHODS: This retrospective, Institutional Review Board-approved study, conducted at a National Cancer Institute-Designated Comprehensive Cancer Center with a multi-disciplinary rectal cancer disease center, included patients undergoing rectal MRI for primary staging January 1, 2018-August 30, 2020. Data collection included patient demographics, initial clinical stage via MRI report, pathologic diagnosis, pathologic stage, and treatment. The primary outcome was concordance of overall clinical and pathologic staging. Secondary outcomes included reasons for mismatched staging. RESULTS: A total 105 rectal adenocarcinoma patients (64 males, mean age 57 ± 12.7 years) had staging MRI followed by surgical resection. A total of 28 patients (27%) had mismatched under-/over- staging. Ten patients (10%) were understaged with mismatched T stage group (clinical stage I, pathologic stage II), five (5%) were understaged with mismatched N stage group (clinical stage I, pathologic stage III), and 13 (12%) were overstaged (clinical stage II-III, pathologic stage 0-I). Treatment matched concordance between clinical and pathologic stages was 86%. CONCLUSION: MRI for primary rectal cancer staging has high concordance with pathology. Future studies to assess strategies for reducing clinically relevant understaging would be beneficial.

Development, Implementation, and Assessment of a Quality, Research, Education, and Wellness (QREW) Professional Development Lecture Series for Radiology Faculty.

RATIONALE AND OBJECTIVES: Professional development is important to academic radiologists. We developed, implemented, and assessed an internal professional development lecture series focusing on the non-interpretative themes of Quality, Research, Education, and Wellness (QREW). MATERIALS AND METHODS: The faculty of a 29-member abdominal radiology division at an academic hospital were invited to deliver 1-hour virtual lectures on noninterpretative topics to division colleagues. Topics were curated by division leadership based on the perceived needs of faculty. Anonymous feedback was collected from attendees for quality improvement purposes and analyzed using descriptive statistics and Fisher's exact test. RESULTS: Over 17 months, 13 QREW lectures were delivered. In total, 91 feedback forms were completed by faculty (mean 7 forms, range 2-12 per session). Of these, 57 responses (63%) were by those <7 years post training ("junior faculty"), 34 responses (37%) by those ≥ 7 years from training ("senior faculty"). Most respondents reported low levels of prior instruction (80/90, 89%) and personal knowledge (49/91, 54%) on topics. Compared to senior faculty, a greater proportion of junior faculty reported less prior instruction (73% vs 98%, P < 0.001) and less personal knowledge (32% vs 65%, P < 0.01). Most respondents agreed or strongly agreed that the topics were important to their clinical practice (87/90, 97%), professional development (86/90, 96%), and personal well-being (82/91, 90%). Faculty identified the QREW program as a major contributor to their professional development. CONCLUSION: A noninterpretative professional development lecture series delivered by radiology faculty in a virtual, interactive format is feasible and effective, particularly for junior faculty.

MRI-Targeted, Systematic, or Combined Biopsy for Detecting Clinically Significant Prostate Cancer.

PURPOSE: The aim of this study was to assess MRI-targeted, systematic, or combined prostate biopsy for diagnosing prostate cancer to identify opportunities for diagnostic accuracy improvement. METHODS: This institutional review board-approved, retrospective study, performed at a large, quaternary hospital, included all men undergoing prostate multiparametric MRI (mpMRI) from January 1, 2015, to December 31, 2019, with prostate-specific antigen ≥ 4 ng/mL, biopsy target on mpMRI (Prostate Imaging Reporting and Data System [PI-RADS] 3-5 lesion), and combined targeted and systematic biopsy ≤6 months after MRI. Analysis included the highest grade lesion per patient. The primary outcome was prostate cancer diagnosis by grade group (GG; 1, 2, and ≥3). Secondary outcomes were rates of cancer upgrading by biopsy type and cancer proximity to the targeted biopsy site in patients upgraded by systematic biopsy. RESULTS: Two hundred sixty-seven biopsies (267 patients) were included; 94.4% (252 of 267) were biopsy naive. The most suspicious mpMRI lesion was PI-RADS 3 in 18.7% (50 of 267), PI-RADS 4 in 52.4% (140 of 267), and PI-RADS 5 in 28.8% (77 of 267). Prostate cancer was diagnosed in 68.5% (183 of 267): 22.1% (59 of 267) GG 1, 16.1% (43 of 267) GG 2, and 30.3% (81 of 267) GG ≥ 3. Combined biopsy (124 of 267) yielded more GG ≥ 2 prostate cancer diagnoses than systematic (87 of 267) or targeted (110 of 267) biopsy alone. More GG ≥ 2 cancers were upgraded by targeted biopsy than by systematic biopsy (P = .0062). Systematic biopsy upgrades were in close proximity to the targeted biopsy site in 42.1% (24 of 57); GG ≥ 3 cancers 62.5% (15 of 24) constituted most proximal misses. CONCLUSIONS: In men with prostate-specific antigen ≥ 4 ng/mL and PI-RADS 3, 4, or 5 lesion on mpMRI, combined biopsy led to more prostate cancer diagnoses than targeted or systematic biopsy alone. Cancers upgraded by systematic biopsy proximal and distant from the targeted biopsy site may indicate opportunities for biopsy and mpMRI improvement, respectively.

Residency Program Directors' Views on Research Conducted During Medical School: A National Survey.

PURPOSE: With the United States Medical Licensing Examination Step 1 transition to pass/fail in 2022, uncertainty exists regarding how other residency application components, including research conducted during medical school, will inform interview and ranking decisions. The authors explore program director (PD) views on medical student research, the importance of disseminating that work, and the translatable skill set of research participation. METHOD: Surveys were distributed to all U.S. residency PDs and remained open from August to November 2021 to query the importance of research participation in assessing applicants, whether certain types of research were more valued, productivity measures that reflect meaningful research participation, and traits for which research serves as a proxy. The survey also queried whether research would be more important without a numeric Step 1 score and the importance of research vs other application components. RESULTS: A total of 885 responses from 393 institutions were received. Ten PDs indicated that research is not considered when reviewing applicants, leaving 875 responses for analysis. Among 873 PDs (2 nonrespondents), 358 (41.0%) replied that meaningful research participation will be more important in offering interviews. A total of 164 of 304 most competitive specialties (53.9%) reported increased research importance compared with 99 of 282 competitive (35.1%) and 95 of 287 least competitive (33.1%) specialties. PDs reported that meaningful research participation demonstrated intellectual curiosity (545 [62.3%]), critical and analytical thinking skills (482 [55.1%]), and self-directed learning skills (455 [52.0%]). PDs from the most competitive specialties were significantly more likely to indicate that they value basic science research vs PDs from the least competitive specialties. CONCLUSIONS: This study demonstrates how PDs value research in their review of applicants, what they perceive research represents in an applicant, and how these views are shifting as the Step 1 exam transitions to pass/fail.

Engagement With the Centers for Disease Control and Prevention Coronavirus Self-Checker and Guidance Provided to Users in the United States From March 23, 2020, to April 19, 2021: Thematic and Trend Analysis.

BACKGROUND: In 2020, at the onset of the COVID-19 pandemic, the United States experienced surges in healthcare needs, which challenged capacity throughout the healthcare system. Stay-at-home orders in many jurisdictions, cancellation of elective procedures, and closures of outpatient medical offices disrupted patient access to care. To inform symptomatic persons about when to seek care and potentially help alleviate the burden on the healthcare system, Centers for Disease Control and Prevention (CDC) and partners developed the CDC Coronavirus Self-Checker ("Self-Checker"). This interactive tool assists individuals seeking information about COVID-19 to determine the appropriate level of care by asking demographic, clinical, and nonclinical questions during an online "conversation." OBJECTIVE: This paper describes user characteristics, trends in use, and recommendations delivered by the Self-Checker between March 23, 2020, and April 19, 2021, for pursuing appropriate levels of medical care depending on the severity of user symptoms. METHODS: User characteristics and trends in completed conversations that resulted in a care message were analyzed. Care messages delivered by the Self-Checker were manually classified into three overarching conversation themes: (1) seek care immediately; (2) take no action, or stay home and self-monitor; and (3) conversation redirected. Trends in 7-day averages of conversations and COVID-19 cases were examined with development and marketing milestones that potentially impacted Self-Checker user engagement. RESULTS: Among 16,718,667 completed conversations, the Self-Checker delivered recommendations for 69.27% (n=11,580,738) of all conversations to "take no action, or stay home and self-monitor"; 28.8% (n=4,822,138) of conversations to "seek care immediately"; and 1.89% (n=315,791) of conversations were redirected to other resources without providing any care advice. Among 6.8 million conversations initiated for self-reported sick individuals without life-threatening symptoms, 59.21% resulted in a recommendation to "take no action, or stay home and self-monitor." Nearly all individuals (99.8%) who were not sick were also advised to "take no action, or stay home and self-monitor." CONCLUSIONS: The majority of Self-Checker conversations resulted in advice to take no action, or stay home and self-monitor. This guidance may have reduced patient volume on the medical system; however, future studies evaluating patients' satisfaction, intention to follow the care advice received, course of action, and care modality pursued could clarify the impact of the Self-Checker and similar tools during future public health emergencies.

Spatial modeling of vaccine deserts as barriers to controlling SARS-CoV-2.

BACKGROUND: COVID-19 vaccine distribution is at risk of further propagating the inequities of COVID-19, which in the United States (US) has disproportionately impacted the elderly, people of color, and the medically vulnerable. We sought to measure if the disparities seen in the geographic distribution of other COVID-19 healthcare resources were also present during the initial rollout of the COVID-19 vaccine. METHODS: Using a comprehensive COVID-19 vaccine database (VaccineFinder), we built an empirically parameterized spatial model of access to essential resources that incorporated vaccine supply, time-willing-to-travel for vaccination, and previous vaccination across the US. We then identified vaccine deserts-US Census tracts with localized, geographic barriers to vaccine-associated herd immunity. We link our model results with Census data and two high-resolution surveys to understand the distribution and determinates of spatially accessibility to the COVID-19 vaccine. RESULTS: We find that in early 2021, vaccine deserts were home to over 30 million people, >10% of the US population. Vaccine deserts were concentrated in rural locations and communities with a higher percentage of medically vulnerable populations. We also find that in locations of similar urbanicity, early vaccination distribution disadvantaged neighborhoods with more people of color and older aged residents. CONCLUSION: Given sufficient vaccine supply, data-driven vaccine distribution to vaccine deserts may improve immunization rates and help control COVID-19.

COVID-19 has affected the elderly, people of color, and individuals with chronic illnesses more than the general population. Large barriers to accessing the COVID-19 vaccine could make this problem worse. We used a website called VaccineFinder, which has information on the location of most COVID-19 vaccine doses in the US, to measure vaccine accessibility in early 2021. We then identified vaccine deserts, defined as small US regions with poor access to the COVID-19 vaccine. We found that over 10% of the US lived in a vaccine desert. Overall, we found that vaccines were less available to people in rural areas, people of color, and individuals with chronic illnesses. It will be important to reverse this pattern and ensure enough vaccines are sent to these communities to help reduce the spread of COVID-19.

Radiologists' Contribution to Variation in Detecting Clinically Significant Prostate Cancer in Men With Prostate MRI.

OBJECTIVE: Assess radiologists' contribution to variation in clinically significant prostate cancer (csPCa) detection in patients with elevated prostate-specific antigen (PSA) and multiparametric MRI (mpMRI). METHODS: This institutional review board-approved, retrospective cohort study was performed at a tertiary, academic, National Cancer Institute-designated Comprehensive Cancer Center with a multidisciplinary prostate cancer program. Men undergoing mpMRI examinations from January 1, 2015, to December 31, 2019, with elevated PSA (≥4 ng/mL) and biopsy within 6 months pre- or post-MRI or prostatectomy within 6 months post-mpMRI were included. Univariate and multivariable hierarchical logistic regression assessed impact of patient, provider, mpMRI examination, mpMRI report, and pathology factors on the diagnosis of Grade Group ≥ 2 csPCa. RESULTS: Study cohort included 960 MRIs in 928 men, mean age 64.0 years (SD ± 7.4), and 59.8% (555 of 928) had csPCa. Interpreting radiologist was not significant individually (P > .999) or combined with mpMRI ordering physician and physician performing biopsy or prostatectomy (P = .41). Prostate Imaging Reporting and Data System (PI-RADS) category 2 (odds ratio [OR] 0.18, P = .04), PI-RADS category 4 (OR 2.52, P < .001), and PI-RADS category 5 (OR 4.99, P < .001) assessment compared with no focal lesion; PSA density of 0.1 to 0.15 ng/mL/cc (OR 2.46, P < .001), 0.15 to 0.2 ng/mL/cc (OR 2.77, P < .001), or ≥0.2 ng/mL/cc (OR 4.52, P < .001); private insurance (reference = Medicare, OR 0.52, P = .001), and unambiguous extraprostatic extension on mpMRI (OR 2.94, P = .01) were independently associated with csPCa. PI-RADS 3 assessment (OR 1.18, P = .56), age (OR 0.99, P = .39), and African American race (OR 0.90, P = .75) were not. DISCUSSION: Although there is known in-practice variation in radiologists' interpretation of mpMRI, in our multidisciplinary prostate cancer program we found no significant radiologist-attributable variation in csPCa detection.

The effect of intraoperative lidocaine administration in a disrupted erector spinae fascial plane on intercostal transcranial motor evoked potentials.

STUDY OBJECTIVE: Erector spinae plane (ESP) blocks have been recently described for postoperative pain management following spine surgery but their effects on intraoperative neuromonitoring are unknown. DESIGN: Retrospective cohort study. SETTING: Pediatric patients at a tertiary care center. PATIENTS: 26 pediatric patients who received bilateral surgically-placed ESP catheters for single-stage posterior spine fusion (PSF) from August 2020 to June 2021. INTERVENTIONS: Patients in this study did not receive any special interventions as part of this observational retrospective study. MEASUREMENTS: This retrospective study investigated the effects of local anesthesia administration through bilateral surgically-placed ESP catheters on intraoperative intercostal transcranial motor evoked potentials (tcMEPs) in the setting of a disrupted erector spinae fascial plane in pediatric patients undergoing single-stage posterior spine fusion. MAIN RESULTS: Of the 26 patients that received bilateral surgically-placed ESP catheters for pediatric posterior spine fusion surgery, none exhibited any changes in intercostal tcMEPs attributable to intraoperative lidocaine administration through the ESP catheters. CONCLUSIONS: The administration of a local anesthetic into a disrupted erector spinae fascial plane does not appear to interfere with intraoperative neuromonitoring of posterior spine fusion surgeries.

Learning From Experience- Confronting Challenges and Adapting to Change in a Large Academic Abdominal Radiology Practice: Insights From a Faculty Retreat.

RATIONALE: Substantial organizational changes, increasing clinical volumes, and the COVID-19 pandemic presented compound stressors to faculty radiologists in our large academic abdominal radiology division and necessitated multiple changes in our practice. METHODS: To address the challenges and establish group consensus, we conducted a virtual divisional faculty retreat centered on themes of team building, clinical work, trainee education, and faculty mentorship. A pre-retreat survey evaluated satisfaction with aspects of professional life and clinical work practices and invited personal reflections. Survey data were presented in the retreat segments focused on each theme, and subsequent discussion was facilitated in small group breakouts. RESULTS: Responses to the team-building survey revealed common values and sources of gratitude, including health, family and meaningful work and relationships. Faculty reported a strong sense of personal accomplishment, but with varied emotional exhaustion scores. Faculty were satisfied with remote work assignments but identified opportunities to improve the clinical work schedule including reversion of some remote assignments to in-person and increased interventional radiology shift staggering. Compared to pre-COVID practice, faculty respondents perceived giving lower quality and less frequent feedback to trainees; evolving educational resource needs were identified. A more formal approach to faculty mentoring was sought. A post-retreat survey revealed high participant satisfaction. OUTCOMES: In the future, we plan to continue divisional retreat activities to respond to evolving challenges and further improve team building, clinical workflow, trainee education, and faculty mentorship.

Sharps Injuries Related to Subdermal Needles in the Orbicularis Oris During Intraoperative Neurophysiologic Monitoring.

PURPOSE: Little is known about the incidence and nature of sharps injuries caused by subdermal intraoperative neurophysiologic monitoring (IONM) needle electrodes. In their institution, the authors observed a series of sharps injuries attributed to placement of needles in the orbicularis oris (OO). METHODS: One large academic institution's sharps injury monitoring database was queried for all reported events over 3 years. The de-identified list was filtered for sharps events occurring in the operating room, and the descriptions of the sharps injuries were individually evaluated. Interventions were performed to attempt to decrease the number of sharps injuries from IONM needles, particularly those placed in OO. Similar data were then collected for 3 months post-intervention. RESULTS: Pre-intervention, 327 sharps injuries were reported over the span of 3 years, of which 13 (4.0%) were attributed to IONM needles not in OO and 5 (1.5%) were attributed to IONM needles in OO. Post-intervention, 41 sharps injuries were reported in 3 months, of which 5 (12.2%) were attributed to IONM needles not in OO and 1 (2.4%) was attributed to needles in OO. CONCLUSIONS: The placement of subdermal needles in the OO presents a disproportionately high risk of sharps injury. Interventions were performed to attempt to decrease the rate of sharps injuries from needles in OO; the post-intervention increase in events was likely skewed by small sample sizes. The implementation of these changes and the ongoing surveillance of injury cases may be important data to help decrease the number of sharps injuries attributed to IONM needles.

Clinical Neurophysiology Fellowship Program Directors Survey on a Standardized Fellowship Match Process: A Call for Action.

PURPOSE: To survey US Clinical Neurophysiology (CNP) fellowship program directors on the nature of CNP and related training programs, current recruitment cycle, and views for a standardized process. METHODS: A 23-question electronic survey was sent to all 93 US Accreditation Council for Graduate Medical Education-accredited CNP fellowship program directors from December 2020 to January 2021. RESULTS: The response rate was 60%. There was great variability in the number of CNP positions and CNP tracks offered. The following tracks were identified: 48% EEG dominant, 26% EMG dominant, 22% split equally between EEG and EMG, and 2% and 1% were neurophysiologic intraoperative monitoring and autonomic dominant, respectively. Of the responding institutions, 43% offered a second year of training options to CNP fellows, mainly in conjunction with Epilepsy fellowship, which was pursued by 25% of CNP fellows. Many programs indicated flexibility in their design between different CNP tracks or between CNP and other related training programs based on the available candidates. The median percentage of CNP fellowship positions filled over the last 5 years was 80%, and there was great variation in the recruitment timeline across institutions. Overall, 86% of program directors favored a universal timeline and 71% favored a formal match for CNP. The respondents were split between an independent CNP match (39%) and joining the initiatives of affiliate societies on a standardized process (61%). CONCLUSIONS: There is significant heterogeneity in the makeup of the CNP fellowship programs and the recruitment process. The majority of CNP program directors are in favor of standardization of the recruitment process.

An Evaluation of the Text Illness Monitoring (TIM) Platform for COVID-19: Cross-sectional Online Survey of Public Health Users.

BACKGROUND: The US public health response to the COVID-19 pandemic has required contact tracing and symptom monitoring at an unprecedented scale. The US Centers for Disease Control and Prevention and several partners created the Text Illness Monitoring (TIM) platform in 2015 to assist US public health jurisdictions with symptom monitoring for potential novel influenza virus outbreaks. Since May 2020, 142 federal, state, and local public health agencies have deployed TIM for COVID-19 symptom monitoring. OBJECTIVE: The aim of this study was to evaluate the utility, benefits, and challenges of TIM to help guide decision-making for improvements and expansion to support future public health emergency response efforts. METHODS: We conducted a brief online survey of previous and current TIM administrative users (admin users) from November 28 through December 21, 2020. Closed- and open-ended questions inquired about the onboarding process, decision to use TIM, groups monitored with TIM, comparison of TIM to other symptom monitoring systems, technical challenges and satisfaction with TIM, and user support. A total of 1479 admin users were invited to participate. RESULTS: A total of 97 admin users from 43 agencies responded to the survey. Most admin users represented the Indian Health Service (35/97, 36%), state health departments (26/97, 27%), and local or county health departments (18/97, 19%), and almost all were current users of TIM (85/94, 90%). Among the 43 agencies represented, 11 (26%) used TIM for monitoring staff exclusively, 13 (30%) monitored community members exclusively, and 19 (44%) monitored both staff and community members. Agencies most frequently used TIM to monitor symptom development in contacts of cases among community members (28/43, 65%), followed by symptom development among staff (27/43, 63%) and among staff contacts of cases (24/43, 56%). Agencies also reported using TIM to monitor patients with COVID-19 for the worsening of symptoms among staff (21/43, 49%) and community members (18/43, 42%). When asked to compare TIM to previous monitoring systems, 78% (40/51) of respondents rated TIM more favorably than their previous monitoring system, 20% (10/51) said there was no difference, and 2% (1/51) rated the previous monitoring system more favorably than TIM. Most respondents found TIM favorable in terms of time burden, staff burden, timeliness of the data, and the ability to monitor large population sizes. TIM compared negatively to other systems in terms of effort to enroll participants (ie, persons TIM monitors) and accuracy of the data. Most respondents (76/85, 89%) reported that they would highly or somewhat recommend TIM to others for symptom monitoring. CONCLUSIONS: This evaluation of TIM showed that agencies used TIM for a variety of purposes and rated TIM favorably compared to previously used monitoring systems. We also identified opportunities to improve TIM; for example, enhancing the flexibility of alert deliveries would better meet admin users' varying needs. We also suggest continuous program evaluation practices to assess and respond to implementation gaps.

Direct brainstem somatosensory evoked potentials for cavernous malformations.

OBJECTIVE: Brainstem cavernous malformations (CMs) often require resection due to their aggressive natural history causing hemorrhage and progressive neurological deficits. The authors report a novel intraoperative neuromonitoring technique of direct brainstem somatosensory evoked potentials (SSEPs) for functional mapping intended to help guide surgery and subsequently prevent and minimize postoperative sensory deficits. METHODS: Between 2013 and 2019 at the Stanford University Hospital, intraoperative direct brainstem stimulation of primary somatosensory pathways was attempted in 11 patients with CMs. Stimulation identified nucleus fasciculus, nucleus cuneatus, medial lemniscus, or safe corridors for incisions. SSEPs were recorded from standard scalp subdermal electrodes. Stimulation intensities required to evoke potentials ranged from 0.3 to 3.0 mA or V. RESULTS: There were a total of 1 midbrain, 6 pontine, and 4 medullary CMs-all with surrounding hemorrhage. In 7/11 cases, brainstem SSEPs were recorded and reproducible. In cases 1 and 11, peripheral median nerve and posterior tibial nerve stimulations did not produce reliable SSEPs but direct brainstem stimulation did. In 4/11 cases, stimulation around the areas of hemosiderin did not evoke reliable SSEPs. The direct brainstem SSEP technique allowed the surgeon to find safe corridors to incise the brainstem and resect the lesions. CONCLUSIONS: Direct stimulation of brainstem sensory structures with successful recording of scalp SSEPs is feasible at low stimulation intensities. This innovative technique can help the neurosurgeon clarify distorted anatomy, identify safer incision sites from which to evacuate clots and CMs, and may help reduce postoperative neurological deficits. The technique needs further refinement, but could potentially be useful to map other brainstem lesions.

Rectal MRI after neoadjuvant chemoradiation therapy: a pictorial guide to interpretation.

Magnetic resonance imaging (MRI) is the current reference standard imaging modality for restaging rectal cancer after neoadjuvant chemoradiation and is used to guide clinical management decisions. This pictorial essay provides an illustrative atlas of the key MRI features used to assess rectal cancer after treatment. MRI findings of residual tumor including non-mucinous, mucinous, and signet-ring cell adenocarcinoma subtypes are correlated with histopathology. Imaging appearances of treatment changes that mimic residual tumor in the setting of confirmed pathological complete response at resection are illustrated. Treatment complications are also shown. Knowledge of these imaging findings and their importance may help radiologists comply with all elements of the structured reporting templates proposed by the Rectal Cancer Disease Focused Panel of the Society of Abdominal Radiology and by the European Society of Gastrointestinal and Abdominal Radiology.

Assessing ablation margins of FDG-avid liver tumors during PET/CT-guided thermal ablation procedures: a retrospective study.

BACKGROUND: To retrospectively assess liver tumor ablation margins using intraprocedural PET/CT images from FDG PET/CT-guided microwave or cryoablation procedures and to correlate minimum margin measurements with local progression outcomes. METHODS: Fifty-six patients (ages 36 to 85, median 62; 32 females) with 77 FDG-avid liver tumors underwent 60 FDG PET/CT guided, percutaneous microwave, or cryoablation procedures. Single breath-hold PET/CT images were used for intraprocedural assessment of the tumor ablation margin: liver tumors remained visible on PET immediately following ablation; microwave ablation zones were visible using contrast-enhanced CT; cryoablation zones (ice balls) were visible using unenhanced CT. Two readers retrospectively determined ablation margin assessability and measured the minimum ablation margin on intraprocedural PET/CT (n = 77) and postprocedural MRI (n = 56). Local tumor progression was assessed on all available follow-up imaging (1-49 months, mean 15). Local tumor progression was correlated with PET/CT minimum margin measurements using clustered survival models for 61 tumors. RESULTS: Minimum ablation margins were more often assessable using intraprocedural PET/CT (≥ 73/77 tumors, 95%) than postprocedural MRI (≤ 35/56 tumors, 63%). In 61 tumors with PET/CT-assessable margins (excluding tumors with overlapping ablations after PET/CT), there was a 6-fold increased risk of local tumor progression [hazard ratio (HR) 6.05; P = 0.004] for minimum ablation margins < 5 mm. CONCLUSION: Breath-hold PET/CT scans, during PET/CT-guided microwave or cryoablation procedures for FDG-avid liver tumors, enable reliable intraprocedural assessment of the entire tumor ablation margin; a minimum PET/CT ablation margin threshold of 5 mm correlates well with local tumor progression outcomes.

F-18 FDG perfusion PET: intraprocedural assessment of the liver tumor ablation margin.

PURPOSE: To evaluate 18F-fluorodeoxyglucose (FDG) perfusion PET during FDG PET/CT-guided liver tumor microwave ablation procedures for assessing the ablation margin and correlating minimum margin measurements with local progression. METHODS: This IRB-approved, HIPAA-compliant study included 20 adult patients (11 M, 9 F; mean age 65) undergoing FDG PET/CT-guided liver microwave ablation to treat 31 FDG-avid tumors. Intraprocedural FDG perfusion PET was performed to assess the ablation margin. Intraprocedural decisions regarding overlapping ablations were recorded. Two readers retrospectively interpreted intraprocedural perfusion PET and postprocedural contrast-enhanced MRI. Assessability of the ablation margin and minimum margin measurements were recorded. Imaging follow-up for local progression ranged from 30 to 574 days (mean 310). Regression modeling of minimum margin measurements was performed. Hazard ratios were calculated to correlate an ablation margin threshold of 5 mm with outcomes. RESULTS: Intraprocedural perfusion PET prompted additional overlapping ablations of two tumors, neither of which progressed. Incomplete ablation or local progression occurred in 8/31 (26%) tumors. With repeat ablation, secondary efficacy was 26 (84%) of 31. Both study readers deemed ablation margins fully assessable more often using perfusion PET than MRI (OR 69.7; CI 6.0, 806.6; p = 0.001). Minimum ablation margins ≥ 5 mm on perfusion PET correlated with a low risk of incomplete ablation/local progression by both study readers (HR 0.08 and 0.02, p < 0.001). CONCLUSION: Intraprocedural FDG perfusion PET consistently enabled complete liver tumor microwave ablation margin assessments, and the perfusion PET minimum ablation margin measurements correlated well with local outcomes. Clinical trial registration clinicaltrials.gov (NCT02018107).