The Value of Isosulfan Blue Dye in Addition to Isotope Scanning in the Identification of the Sentinel Lymph Node in Breast Cancer Patients With a Positive Lymphoscintigraphy: A Randomized Controlled Trial (ISRCTN98849733).

BACKGROUND: Sentinel lymph node biopsy (SLNB) has become the gold standard for axillary staging. Debate remains as to the optimal method of SLN detection. OBJECTIVES: Determine whether patients undergoing an SLNB required the addition of isosulfan blue dye to radioisotope when an SLN was identified on a preoperative lymphoscintigram. METHODS: A prospective randomized controlled trial comparing the combination of radioisotope and blue dye versus radioisotope alone was performed between March 2010 and September 2012. The trial protocol was registered with Current Controlled Trials. Women with clinically and radiologically node-negative breast cancer with a positive preoperative lymphoscintigram were eligible for inclusion. RESULTS: A total of 667 patients were included in the analysis with 342 patients receiving the combination (blue dye and radioisotope) and 325 patients receiving radioisotope alone. The groups were evenly matched both demographically and pathologically. The mean age was 48 years (48.3 vs 47.7 years; P = 0.47), the mean tumour size was 24.2 mm (24.3 mm vs 24.1 mm; P = 0.7) and there was no statistically significant difference in the grade of the tumors between the 2 groups (P = 0.58). There was no difference in the identification rate, nor was that in the number of nodes retrieved between the 2 groups (P = 0.30). There was no difference in the number of positive lymph nodes that were identified between the 2 groups (23.8% vs 22.1%; P = 0.64). CONCLUSIONS: This study failed to demonstrate an advantage with the addition of isosulfan blue dye to radioisotope in the identification of the SLN in the presence of a positive preoperative lymphoscintigram.

Hepatocellular carcinoma: illustrated guide to systematic radiologic diagnosis and staging according to guidelines of the American Association for the Study of Liver Diseases.

Hepatocellular carcinoma is a malignancy that predominantly occurs in the setting of cirrhosis. Its incidence is rising worldwide. Hepatocellular carcinoma differs from most malignancies because it is commonly diagnosed on the basis of imaging features alone, without histologic confirmation. The guidelines from the American Association for the Study of Liver Diseases (AASLD) are a leading statement for the diagnosis and staging of hepatocellular carcinoma, and they have recently been updated, incorporating several important changes. AASLD advocates the use of the Barcelona Clinic Liver Cancer (BCLC) staging system, which combines validated imaging and clinical predictors of survival to determine stage and which links staging with treatment options. Each stage of the BCLC system is outlined clearly, with emphasis on case examples. Focal liver lesions identified at ultrasonographic surveillance in patients with cirrhosis require further investigation. Lesions larger than 1 cm should be assessed with multiphasic computed tomography or magnetic resonance imaging. Use of proper equipment and protocols is essential. Lesions larger than 1 cm can be diagnosed as hepatocellular carcinoma from a single study if the characteristic dynamic perfusion pattern of arterial hyperenhancement and venous or delayed phase washout is demonstrated. If the imaging characteristics of hepatocellular carcinoma are not met, the alternate modality should be performed. Biopsy should be used if neither modality is diagnostic of hepatocellular carcinoma. Once the diagnosis has been made, the cancer should be assigned a BCLC stage, which will help determine suitable treatment options. Radiologists require a systematic approach to diagnose and stage hepatocellular carcinoma with appropriate accuracy and precision.

Development and validation of core entrustable professional activities for abdominal radiology.

OBJECTIVES: To develop and validate European entrustable professional activities (EPAs) for sub-specialised hepatobiliary and gastrointestinal (HB/GI) diagnostic imaging. MATERIALS AND METHODS: Both European Society of Radiology and national curricula in HB/GI diagnostic radiology were thoroughly reviewed, resulting in preliminary EPAs drafted by a pilot group of expert radiologists in 2 different countries. Each EPA was fully described with 7 components (Specification/limitations; Potential risks of failing; Relevant domains of competence; Required experience, knowledge, skills, attitude and behaviour; Assessment information sources to assess progress and ground a summative entrustment decision; Entrustment for which level of supervision is to be reached; and Expiration date). The modified Delphi method with 3 Delphi rounds was chosen for validation. Content validity index (CVI) and median values were used for validation. RESULTS: There were 15 preliminary EPAs, some of them divided according to 2 levels: resident and fellow level. The 37 members of the Delphi group were based in 2 different European countries with a background experience of 10 represented countries. Subsequent to the first Delphi round, 6 EPAs were accepted (CVI ≥ 0.8, median ≥ 4), 6 needed major revisions (CVI 0.7-0.79, median ≥ 4), 3 were rejected (CVI < 0.7) and 1 was added. After the second Delphi round, both the 6 revised EPAs and the additional one met the validation criteria (CVI ≥ 0.8, median ≥ 4). Finally, 13 EPAs were validated during the 3rd Delphi round with an agreement percentage of 95-100%. CONCLUSION: This study creates and validates EPAs for sub-specialised HB/GI diagnostic imaging. CRITICAL RELEVANCE STATEMENT: Thirteen EPAs for sub-specialised hepatobiliary and gastrointestinal diagnostic imaging were created with a strong methodology, and as a first example set in sub-specialised diagnostic imaging, they provide a template for others to be created. KEY POINTS: • The competence-based teaching in medical studies has recently been reintroduced through EPAs. • Thirteen EPAs have been developed for hepatobiliary and gastrointestinal sub-specialised diagnostic imaging. • These EPAs were validated using a Delphi modified method and provide a template for other to be created.

Clinical features and outcomes of appendiceal neuroendocrine tumours: 10 year audit from the Irish NET Centre of Excellence.

Appendiceal neuroendocrine tumours (aNETs) are rare neoplasms of the gastrointestinal tract often diagnosed incidentally at the time of appendicectomy. Appendicectomy is considered curative in the majority of cases but guidelines recommend right-sided hemicolectomy (RHC) for those with specific high-risk features despite no data supporting a survival benefit. We performed a retrospective search of multi-disciplinary tumour board and pathology databases from 2012 to 2022 to identify cases of aNET treated at our centre. Follow-up data were obtained from the electronic healthcare records. A total of 142 cases of aNET were included for analysis. Mean age at presentation was 34, of which 76% were female and 92% of aNETs were located in the tip/middle of the appendix; 90% were grade 1, and 93% had R0 resection. Tumour size was <1 cm in 54%, 1-2 cm in 36%, >2 cm in 9%. A total of 43 patients (30%) underwent RHC with lymph node metastases identified in 16 (37%). Lymph node metastases were associated with tumour size >2 cm (p = .008) and higher tumour grade (p = .041) on multivariate analysis. For aNET 1-2 cm, lymph node metastases were identified in 7/22 who had RHC (32%) with tumour grade the only significant risk factor (p = .046). Distant metastases were identified in 2 cases (1%), diagnosed synchronously and associated with grade 2 tumours. Overall survival for those with lymph node metastases was 100% after a median 4 years. Progression-free survival was 93%, with a single case of disease progression associated with synchronous distant metastases at initial diagnosis. Lymph node metastases in aNET are associated with higher tumour grade and tumour size >2 cm. Disease progression in the setting of lymph node metastases is rare. The significance of lymph node metastases and need for completion RHC remains uncertain.

A predictive model of suitability for minimally invasive parathyroid surgery in the treatment of primary hyperparathyroidism [corrected].

BACKGROUND: Improved preoperative localizing studies have facilitated minimally invasive approaches in the treatment of primary hyperparathyroidism (PHPT). Success depends on the ability to reliably select patients who have PHPT due to single-gland disease. We propose a model encompassing preoperative clinical, biochemical, and imaging studies to predict a patient's suitability for minimally invasive surgery. METHODS: For the purposes of the present study, 180 consecutive patients were included for analysis. A 5-variable model based on preoperative ionized serum calcium (>1.4 mmol/l), intact parathyroid hormone level (≥ 2 times the upper limit of normal), positive sestamibi scan for a single affected gland, positive ultrasound scan for a single gland, and concordance between the two imaging modalities for single-gland disease at a similar location was employed, where a score of 1 was allocated for each variable present. RESULTS: Of the 180 patients, 62 (34%) underwent bilateral exploration, 63 (36%) underwent unilateral exploration, and 55 (30%) underwent minimally invasive parathyroidectomy. The results showed that 92% had single-gland disease, 3% had double adenomas, and 5% had hyperplasia. Biochemical cure was achieved in 98.9%. Mean follow-up was 153 days (range: 80-342 days). With the predictive scoring model, a score of ≥ 3 had a positive predictive value of 100% for single-gland disease. CONCLUSIONS: A scoring model encompassing preoperative biochemical and imaging data can be successfully employed to predict suitability for minimally invasive surgery in the majority of patients with single-gland disease.

Increasing radiation exposure from computed tomography in liver transplant recipients over time.

OBJECTIVES: To evaluate changes in radiation exposure from computed tomography (CT) among patients undergoing liver transplantation in our unit over a 10-year period. METHODS: We evaluated 134 elective patients, without hepatocellular carcinoma or cholangiocarcinoma who underwent transplantation in 2007-2008 and 2017-2018. CT scans performed in our hospital up to 2 years pre transplant and 1 year post transplant were evaluated. RESULTS: There was an increase in mean estimated effective radiation dose per patient in 2017-2018 compared to 2007-2008 (77.8 mSv ± 6.2 vs 56.7 mSv ± 5.9, p < 0.05). This change was mainly due to an increased number of pre-transplant CT scans per patient (2.9 ± 0.3 vs 1.4 ± 0.14, p = 0.0001). High radiation dose scan protocols were more frequently used in 2017-2018, with 4-phase liver CT accounting for a larger proportion of scans both pre-transplant (61% vs 43%, p = 0.004) and post-transplant (29% vs 13%, p = 0.002). A greater proportion of patients were exposed to > 100 mSv of ionising radiation in the 2017-2018 patients (29% vs 11%, p < 0.01). These figures are likely to be a significant under-estimate as they exclude other imaging modalities and CT scans performed at other institutions. CONCLUSION: Radiation exposure from diagnostic imaging has increased among liver transplant recipients at our institution over the last decade. This appears to be due to an increase in the number of CT scans performed, and a shift towards higher dose scan protocols.

Pulmonary CT angiography protocol adapted to the hemodynamic effects of pregnancy.

OBJECTIVE: The purpose of this study was to compare the image quality of a standard pulmonary CT angiography (CTA) protocol with a pulmonary CTA protocol optimized for use in pregnant patients with suspected pulmonary embolism (PE). MATERIALS AND METHODS: Forty-five consecutive pregnant patients with suspected PE were retrospectively included in the study: 25 patients (group A) underwent standard-protocol pulmonary CTA and 20 patients (group B) were imaged using a protocol modified for pregnancy. The modified protocol used a shallow inspiration breath-hold and a high concentration, high rate of injection, and high volume of contrast material. Objective image quality and subjective image quality were evaluated by measuring pulmonary arterial enhancement, determining whether there was transient interruption of the contrast bolus by unopacified blood from the inferior vena cava (IVC), and assessing diagnostic adequacy. RESULTS: Objective and subjective image quality were significantly better for group B-that is, for the group who underwent the CTA protocol optimized for pregnancy. Mean pulmonary arterial enhancement and the percentage of studies characterized as adequate for diagnosis were higher in group B than in group A: 321 ± 148 HU (SD) versus 178 ± 67 HU (p = 0.0001) and 90% versus 64% (p = 0.05), respectively. Transient interruption of contrast material by unopacified blood from the IVC was observed more frequently in group A (39%) than in group B (10%) (p = 0.05). CONCLUSION: A pulmonary CTA protocol optimized for pregnancy significantly improved image quality by increasing pulmonary arterial opacification, improving diagnostic adequacy, and decreasing transient interruption of the contrast bolus by unopacified blood from the IVC.

Whole body imaging in the abdominal cancer patient: pitfalls of PET-CT.

Proper interpretation of PET-CT images requires knowledge of the normal physiological distribution of the tracer, frequently encountered physiological variants, and benign pathological causes of FDG uptake that can be confused with a malignant neoplasm. In addition, not all malignant processes are associated with avid tracer uptake. A basic knowledge of the technique of image acquisition is also required to avoid pitfalls such as misregistration of anatomical and scintigraphic data. This article reviews these potential pitfalls as they apply to the abdomen and pelvis of patients with cancer.

Vascular findings on FDG PET/CT.

Since its introduction into clinical practice, 2-deoxy-2-[18F]flu-D-glucose (FDG) positron emission tomography/computed tomography (PET/CT) has become firmly established in the field of oncological imaging, with a growing body of evidence demonstrating its use in infectious and inflammatory vascular pathologies. This pictorial review illustrates the utility of FDG PET/CT as a diagnostic tool in the investigation of vascular disease and highlights some of the more common incidental vascular findings that PET reporters may encounter on standard oncology FDG PET/CTs, including atherosclerosis, large vessel vasculitis, complications of vascular grafts, infectious aortitis and acute aortic syndromes.

TIRADS Management Guidelines in the Investigation of Thyroid Nodules; Illustrating the Concerns, Costs, and Performance.

CONTEXT: Ultrasound (US) risk-stratification systems for investigation of thyroid nodules may not be as useful as anticipated. OBJECTIVE: We aimed to assess the performance and costs of the American College of Radiology Thyroid Image Reporting And Data System (ACR-TIRADS). DESIGN SETTINGS AND PARTICIPANTS: We examined the data set upon which ACR-TIRADS was developed, and applied TR1 or TR2 as a rule-out test, TR5 as a rule-in test, or applied ACR-TIRADS across all nodule categories. We assessed a hypothetical clinical comparator where 1 in 10 nodules are randomly selected for fine needle aspiration (FNA), assuming a pretest probability of clinically important thyroid cancer of 5%. RESULTS: The gender bias (92% female) and cancer prevalence (10%) of the data set suggests it may not accurately reflect the intended test population. Applying ACR-TIRADS across all nodule categories did not perform well, with sensitivity and specificity between 60% and 80% and overall accuracy worse than random selection (65% vs 85%). Test performance in the TR3 and TR4 categories had an accuracy of less than 60%. Using TR5 as a rule-in test was similar to random selection (specificity 89% vs 90%). Using TR1 and TR2 as a rule-out test had excellent sensitivity (97%), but for every additional person that ACR-TIRADS correctly reassures, this requires >100 ultrasound scans, resulting in 6 unnecessary operations and significant financial cost. CONCLUSIONS: Perhaps surprisingly, the performance ACR-TIRADS may often be no better than random selection. The management guidelines may be difficult to justify from a cost/benefit perspective. A prospective validation study that determines the true performance of TIRADS in the real-world is needed.

Pulmonary embolism in pregnancy: comparison of pulmonary CT angiography and lung scintigraphy.

OBJECTIVE: The purpose of this study was to retrospectively compare the diagnostic adequacy of lung scintigraphy with that of pulmonary CT angiography (CTA) in the care of pregnant patients with suspected pulmonary embolism. MATERIALS AND METHODS: Patient characteristics, radiology report content, additional imaging performed, final diagnosis, and diagnostic adequacy were recorded for pregnant patients consecutively referred for lung scintigraphy or pulmonary CTA according to physician preference. Measurements of pulmonary arterial enhancement were performed on all pulmonary CTA images of pregnant patients. Lung scintigraphy and pulmonary CTA studies deemed inadequate for diagnosis at the time of image acquisition were further assessed, and the cause of diagnostic inadequacy was determined. The relative contribution of the inferior vena cava to the right side of the heart was measured on nondiagnostic CTA images and compared with that on CTA images of age-matched nonpregnant women, who were the controls. RESULTS: Twenty-eight pulmonary CTA examinations were performed on 25 pregnant patients, and 25 lung scintigraphic studies were performed on 25 pregnant patients. Lung scintigraphy was more frequently adequate for diagnosis than was pulmonary CTA (4% vs 35.7%) (p = 0.0058). Pulmonary CTA had a higher diagnostic inadequacy rate among pregnant than nonpregnant women (35.7% vs 2.1%) (p < 0.001). Transient interruption of contrast material by unopacified blood from the inferior vena cava was identified in eight of 10 nondiagnostic pulmonary CTA studies. CONCLUSION: We found that lung scintigraphy was more reliable than pulmonary CTA in pregnant patients. Transient interruption of contrast material by unopacified blood from the inferior vena cava is a common finding at pulmonary CTA of pregnant patients.

FDG PET in preoperative assessment of colorectal liver metastases combining "evidence-based practice" and "technology assessment" methods to develop departmental imaging protocols: should FDG PET be routinely used in the preoperative assessment of patients with colorectal liver metastases?

In today's environment of progressively evolving and expensive imaging modalities, radiologists are asked to justify the use of resources to patients, referring physicians, hospital management, and third party payers. With this aim, the radiologist may use "top-down" or "bottom-up" "evidence-based practice" (EBP) techniques. "Top-down" suggests that the practitioner should wait until a higher authority, external to their practice, generates a solution to practice dilemmas (e.g., National Institute for Health and Clinical Excellence [NICE] guidelines). "Bottom-up" however, is based on the theory that the ordinary practitioner is best served by a decentralized approach to problem solving that is internal to their practice. The technology assessment framework modeled by Mackenzie and Dixon comprehensively assesses the effects of imaging using levels of efficacy including diagnostic performance, diagnostic impact, and therapeutic impact, impact on health and cost effectiveness. In this article, we describe how issues regarding new imaging modalities in ordinary radiology practice can be addressed by using stepwise "bottom-up" EBP techniques combined with the technology assessment framework. We also detail how EBP techniques form an integral part of practice-based learning among radiology residents as part of noninterpretive residency training. The following clinical scenario is used: your hospital's chief hepatobiliary surgeon writes to your department regarding the lack of access to 18-fluoro-2-deoxy-D-glucose positron emission tomography in the preoperative assessment of patients with colorectal cancer liver metastases under consideration for hepatic resection. How would you approach this problem? Here is how we would do it.

Atypia of Undetermined Significance in Thyroid Fine Needle Aspirates: a 4-Year Audit of Thy3a Reporting.

OBJECTIVE: Thyroid nodules are common within the general population. Cytological analysis of fine needle aspirates (FNAs) of these lesions allows for identification of those that require further surgery. A numerical classification system is in place to streamline reporting. The 3a category is used for lesions that are neither benign nor malignant but show atypia of undetermined significance. We reviewed our use and clinical outcomes of Thy3a over a 4-year period. METHODS: All thyroid FNAs performed at this institute from January 2012 to December 2015 were identified from our laboratory information system using SNOMED codes. Cytology was correlated with histology. RESULTS: Of the 1,259 FNAs reported at this institute, Thy3a constituted only 1.2% (n = 16) of all cases, with a malignancy rate of 7%. Five Thy3a cases had a repeat FNA that was reported as Thy2 (benign), 1 as Thy1c (cyst), 1 as Thy3f (follicular lesion), and 1 as Thy5 (malignant). Six cases without repeat FNA were follicular adenomas at resection. Two cases were lost to follow-up. Within all thyroid cytology categories in this 4-year period, we had a false-positive rate of 1.9% and a false-negative rate of 0.3%. CONCLUSIONS: The Thy3a subclassification has varied diagnostic criteria and lacks reproducibility. Despite the rare use of the Thy3a category at our centre, our diagnostic accuracy remained high. At this time, further Thy3a cohort studies are required to assess the real benefits of this category.

FDG PET/CT demonstrates the effectiveness of isolated limb infusion for malignant melanoma.

A 43-year-old woman presented with a nodular melanoma treated with wide excision, split skin graft, and sentinel node biopsy. At 2-year follow up, she was noted to have clinical recurrence at the excision site. FDG PET/CT demonstrated in-transit metastasis in her left thigh in addition to disease at the site of the sentinel node biopsy. Isolated limb infusion was performed with melphalan and dactinomycin. PET/CT at 5 weeks demonstrated resolution of the in-transit metastasis and the disease at the excision site. This report of PET/CT demonstrates the effectiveness of chemotherapy for malignant melanoma delivered by isolated limb infusion.

Positron emission tomography in the investigation of pediatric inflammatory bowel disease.

BACKGROUND: Endoscopic and radiologic studies are frequently required in inflammatory bowel disease (IBD) to determine disease activity, extent of disease, and delineating disease type. Positron emission tomography (PET) using fluorine-18-fluoro-deoxyglucose to identify metabolically active tissues may offer a simple noninvasive alternative to conventional studies in identification and localization of active intestinal inflammation in children with IBD. The aim of this study was to assess the value of PET in identifying active intestinal inflammation compared with conventional endoscopic and radiologic studies, including small bowel follow-through and colonoscopy. METHODS: Sixty-five children were enrolled in the study. This included 55 children (mean age, 13.3 yr; range, 7-18 yr; 20 girls) with newly diagnosed IBD (37) or symptoms suggestive of recurrent disease (18) and 10 children with recurrent abdominal pain (mean age, 12.7 yr; range, 8-15 yr; 7 girls) who were studied with PET, and the results were compared with small bowel follow-through with pneumocolon and/or colonoscopy. Thirty-eight patients had Crohn's disease (17 ileal, 12 ileocolic, 5 pancolonic, 3 left-sided disease, 1 right-sided disease), and 17 had ulcerative colitis (15 pan-colitis, 2 left-sided colitis). Mean time interval between PET and other studies was 30 +/- 17.6 days. RESULTS: PET correctly identified active inflammatory disease in 80% of children with IBD (81.5% with Crohn's disease; 76.4% with ulcerative colitis) and correctly showed no evidence of inflammation in children with recurrent abdominal pain. Gluorine-18-fluoro-deoxyglucose accumulated at sites that corresponded with active disease at colonoscopy in 83.8% of patients and with small bowel follow-through with pneumocolon 75.0% of the time. CONCLUSION: This study suggests that PET offers a noninvasive tool for identifying and localizing active intestinal inflammation in children with IBD. PET may not be able to replace conventional studies; however, it may be useful when conventional studies cannot be performed or fail to be completed.