Types of Evidence Needed to Assess the Clinical Value of Diagnostic Imaging.

AbstractThe evidence underlying the use of advanced diagnostic imaging is based mainly on diagnostic accuracy studies and not on well-designed trials demonstrating improved patient outcomes. This has led to an expansion of low-value and potentially harmful patient care and raises ethical issues around the widespread implementation of tests with incompletely known benefits and harms. Randomized clinical trials are needed to support the safety and effectiveness of imaging tests and should be required for clearance of most new technologies. Large, diverse cohort studies are needed to quantify disease risk associated with many imaging findings, especially incidental findings, to enable evidence-based management. The responsibility to minimize the use of tests with unknown or low value requires engagement of clinicians, medical societies, and the public.

Extragonadal germ cell tumors: A clinicopathologic study with emphasis on molecular features, clinical outcomes and associated secondary malignancies.

Extragonadal germ cell tumors (EGCTs) are rare, representing <5% of all germ cell tumors (GCTs). Whilst EGCTs share morphological and immunohistochemical features with their gonadal counterparts, they tend to be more aggressive and are frequently associated with secondary somatic malignancies. The aim of our study was to evaluate the clinical, morphological and immunohistochemical features, and to analyze tumors for chromosomal abnormalities of 12p, in addition to any novel genetic alterations, in a series of EGCTs. Seventy-seven EGCTs were included. Anterior mediastinum was the most common anatomic site, followed by central nervous system, retroperitoneum, sacroccygeal area, and neck. Whole genome SNP array identified isochromosome 12p in 26% of tumors. Additional cytogenetic abnormalities included the presence of gain of chr 21 in 37% of tumors. Somatic-type malignancies were identified in 8% of patients. Disease progression (metastasis and/or recurrence) was documented in 8 patients, most of whom died from their relapse. Three patients who died of disease had somatic-type malignancies. Mediastinal seminomas had a significantly better overall survival when compared to mediastinal non-seminomatous GCTs. Our study demonstrates that EGCTs share similar histologic features, but diverse clinical outcomes compared to their gonadal counterparts. Outcomes vary according to anatomic location and histologic subtypes. Our data corroborate that somatic-type malignancies are frequently encountered in mediastinal EGCTs and that their presence portends a poorer prognosis.

Sestamibi as an alternative to mebrofenin for the diagnosis of acute cholecystitis: An alternative option during supply chain disruption.

Purpose: To determine the accuracy of Tc-99 m sestamibi for the diagnosis of acute cholecystitis during a supply chain disruption of mebrofenin. Material and methods: During a national shortage of Tc-99 m mebrofenin in 2019, our institution initiated sestamibi imaging for suspected cases of acute cholecystitis using a standard hepatobiliary imaging protocol. Forty-one patients underwent hepatobiliary imaging with sestamibi, 39 to assess for acute cholecystitis. The examinations were initially interpreted by one nuclear medicine physician and subsequently overread by 5 blinded nuclear medicine physicians (8-30 years' experience). SPECT/CT was obtained for 8 of these patients at the discretion of the primary interpreter. An additional 23 asymptomatic patients (6 with prior cholecystectomy) underwent abdominal scintigraphy as a negative control to determine the normal time to sestamibi accumulation in the gallbladder. A composite reference standard was used (chart review by 3 physicians). Sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values were calculated with and without SPECT/CT (mean ± 95%CI). Results: Of 39 symptomatic patients, 17/39 had acute cholecystitis and 22 did not. The sensitivity, specificity, PPV and NPV for acute cholecystitis at planar imaging were 97.6 ± 4.6, 62.7 ± 5.2, 67.0 ± 3.6, and 97.3 ± 5.2 % (N = 39). The values changed to 95.7 ± 4.7, 77.9 ± 4.7, 72.1 ± 4.1, and 97.0 ± 3.3 % when control patients were included (N = 62). With SPECT/CT, these mildly improved to 98.8 ± 2.3 %, 69.1 ± 4.4 %, 71.3 ± 3.2 %, and 98.7 ± 2.6 % (N = 39), but not significantly different. On average, sestamibi activity was detected in the gallbladder in negative controls within 1 h. Conclusion: Tc-99 m sestamibi has excellent sensitivity and NPV for diagnosing acute cholecystitis and can serve as an alternative when mebrofenin is unavailable for evaluating cystic duct obstruction during shortages of standard agents.

Direct Quantification of Gadolinium Retention in Young Patients by ICP-MS Analysis of Extracted Teeth.

In this 10-patient prospective pilot study, we show the feasibility of pragmatic direct ex vivo measurement of gadolinium retention from group II gadolinium-based contrasts agents (GBCAs) in young patients after routine tooth extraction. This noninvasive method may support future research attempting to understand the link between GBCA exposure and clinical outcomes.

Gold nanoshells for prostate cancer treatment: evidence for deposition in abdominal organs.

PURPOSE: Gold-silica nanoshell therapy [AuroShells with subsequent focal laser therapy (AuroLase)] is an emerging targeted treatment modality for prostate cancer. We reviewed pre- and post-treatment unenhanced CT imaging to assess for retained gold-silica nanoshells in the abdomen and pelvis. METHODS: This single-institution retrospective study identified patients in the AuroLase pilot who underwent pre- and post-treatment unenhanced abdominopelvic CT. The attenuation, before and after gold-silica nanoshell administration, of the liver, spleen, pancreas, kidneys, prostate, blood pool, paraspinal musculature, and abnormal lymph nodes were manually measured by two readers. After inter-reader agreement was calculated using intraclass correlation (ICC), a permutation test was used to assess pre- and post-therapy attenuation differences. RESULTS: Four patients met the inclusion criteria. Mean age was 72.3 ± 5.9 years. Median time interval between pre-treatment CT and treatment, and between treatment and post-treatment CT, was 232 days and 236.5 days, respectively. The two readers' attenuation measurements had very high agreement (ICC = 0.99, p < 0.001). The highest differences in organ attenuation between pre- and post-therapy scans were seen in all four patients in the liver and spleen (liver increased by an average of 28.9 HU, p = 0.010; spleen increased by an average of 63.7 HU, p = 0.012). A single measured lymph node increased by an average of 58.9 HU. In the remainder of the measured sites, the change in attenuation from pre- to post-therapy scans ranged from -0.1 to 3.8 HU (p > 0.05). CONCLUSION: Increased attenuation of liver and spleen at CT can be an expected finding in patients who have received gold-silica nanoshell therapy.

Radiologists predict differential resource utilization but not clinical outcome in emergency department patients imaged with ultrasound for right upper quadrant pain.

PURPOSE: Radiologists with diverse training, specialization, and habits interpret imaging in the Emergency Department. It is necessary to understand if their variation predicts differential value. The purpose of this study was to determine whether attending radiologist variation predicts major clinical outcomes in adult Emergency Department patients imaged with ultrasound for right upper quadrant pain. METHODS: Consecutive ED patients imaged with ultrasound for RUQ pain from 10/8/2016 to 8/10/2022 were included (N = 7097). The primary outcome was prediction of hospital admission by signing attending radiologist. Secondary outcomes included: ED and hospital length of stay (LOS), 30-day mortality, 30-day re-presentation rate, subspecialty consultation, advanced imaging follow up (HIDA, MRI, CT), and intervention (ERCP, drainage or surgery). Sample size was determined a priori (detectable effect size: w = 0.06). Data were adjusted for demographic data, Elixhauser comorbidities, number of ED visits in prior year, clinical data, and system factors (38 covariates). P-values were corrected for multiple comparisons (false discovery rate-adjusted p-values). RESULTS: The included ultrasounds were read by 35 radiologists (median exams/radiologist: 145 [74.5-241.5]). Signing radiologist did not predict hospitalization (p = 0.85), abdominopelvic surgery or intervention within 30 days, re-presentation to the Emergency Department within 30 days, or subspecialty consultation. Radiologist did predict difference in Emergency Department length of stay (p < 0.001) although this difference was small and imprecise. HIDA was mentioned variably by radiologists (range 0-19%, p < 0.001), and mention of HIDA in the ultrasound report increased 10-fold the odds of HIDA being performed in the next 72 h (odds ratio 10.4 [8.0-13.4], p < 0.001). CONCLUSION: Radiologist variability did not predict meaningful outcome differences for patients with right upper quadrant pain undergoing ultrasound in the Emergency Department, but when radiologists mention HIDA in their reports, it predicts a 10-fold increase in the odds a HIDA is performed. Radiologists are relied on for interpretation that shapes subsequent patient care, and it is important to consider how radiologist variability can influence both outcome and resource utilization.

Continuity of Radiologists Between Diagnostic Breast Imaging and Image-Guided Breast Biopsy: Impact on Patient-Reported Biopsy Morbidity Experiences.

OBJECTIVE: To determine whether continuity of care between diagnostic breast imaging and subsequent image-guided breast biopsy could reduce patient-reported biopsy-related morbidity. METHODS: This was a prospective, pragmatically randomized, 2-arm health utilities analysis of 200 women undergoing diagnostic breast imaging followed by US- or stereotactic-guided breast biopsy at a single quaternary care center from September 3, 2019, to April 10, 2023. Breast biopsy-naive women with a BI-RADS 4 or 5 finding at diagnostic imaging were randomly scheduled for the typically first available biopsy appointment. One day after biopsy, enrolled patients were administered the Testing Morbidities Index (TMI). The primary outcome was the difference in TMI summary utility scores in patients who did vs did not have the same radiologist perform diagnostic imaging and biopsy. RESULTS: Response rates were 63% (100/159) for the different radiologist cohort and 71% (100/140) for the same radiologist cohort; all respondents answered all questions in both arms. Mean time to biopsy was 7 ± 6 days and 10 ± 9 days, and the number of participating radiologists was 11 and 18, respectively. There was no difference in individual measured domains (pain, fear, or anxiety before procedure; pain, embarrassment, fear, or anxiety during procedure; mental or physical impact after procedure; all P >.00625) or in overall patient morbidity (0.83 [95% CI, 0.81-0.85] vs 0.82 [95% CI: 0.80-0.84], P = .66). CONCLUSION: Continuity of care between diagnostic breast imaging and image-guided breast biopsy did not affect morbidity associated with breast biopsy, suggesting that patients should be scheduled for the soonest available biopsy appointment rather than waiting for the same radiologist.

Adenosine A1R/A3R agonist AST-004 reduces brain infarction in mouse and rat models of acute ischemic stroke.

Acute ischemic stroke (AIS) is the second leading cause of death globally. No Food and Drug Administration (FDA) approved therapies exist that target cerebroprotection following stroke. Our group recently reported significant cerebroprotection with the adenosine A1/A3 receptor agonist, AST-004, in a transient stroke model in non-human primates (NHP) and in a preclinical mouse model of traumatic brain injury (TBI). However, the specific receptor pathway activated was only inferred based on in vitro binding studies. The current study investigated the underlying mechanism of AST-004 cerebroprotection in two independent models of AIS: permanent photothrombotic stroke in mice and transient middle cerebral artery occlusion (MCAO) in rats. AST-004 treatments across a range of doses were cerebroprotective and efficacy could be blocked by A3R antagonism, indicating a mechanism of action that does not require A1R agonism. The high affinity A3R agonist MRS5698 was also cerebroprotective following stroke, but not the A3R agonist Cl-IB-MECA under our experimental conditions. AST-004 efficacy was blocked by the astrocyte specific mitochondrial toxin fluoroacetate, confirming an underlying mechanism of cerebroprotection that was dependent on astrocyte mitochondrial metabolism. An increase in A3R mRNA levels following stroke suggested an intrinsic cerebroprotective response that was mediated by A3R signaling. Together, these studies confirm that certain A3R agonists, such as AST-004, may be exciting new therapeutic avenues to develop for AIS.