Transarterial Embolization for Sporadic Renal Angiomyolipoma: Patient Selection and Technical Considerations for Optimal Therapeutic Outcomes

Although renal angiomyolipoma (AML) is a benign tumor, treatment may be necessary occasionally because it can cause potentially life-threatening retroperitoneal hemorrhage. Transarterial embolization (TAE) is a safe and effective treatment option to prevent the hemorrhagic rupture of AMLs and relieve the symptoms caused by enlarged lesions or active bleeding. However, there is no clear consensus regarding the indications for prophylactic TAE in patients with sporadic renal AMLs. In urgent TAE for bleeding AMLs, there is a likelihood of incomplete embolization when the focus is on stabilizing the clinical symptoms. This pictorial essay discusses the patient selection and technical considerations to achieve optimal therapeutic effects as well as the follow-up findings after TAE.

Development of Entrustable Professional Activity, Core Competencies, and Guidelines in 2021 Radiology Competency Education Project

To provide high-quality training to residents in a rapidly changing medical environment, it is very important to improve the annual training curriculum centered on competency and ensure that training hospitals maintain an environment suitable for training. The Korean Society of Radiology (KSR) has been steadily improving the training system and has suggested the improvement of the training system by strengthening the competency-based evaluation and faculty development. Currently, KSR was selected for the second annual training curriculum systematization construction project in July 2021, and developed entrustable professional activities, core competencies, and assessment guidelines required by the construction project. Therefore, the development process and assessment guidelines will be introduced to residents and the faculty.

Extranodal Malignant Lymphoma Concurrent Involving Female Urethra and Cervix: a Case Report

Extranodal lymphoma presents in almost one-third of all non-Hodgkin lymphoma cases. The gastrointestinal tract, skin, and central nervous system are common sites of involvement, whereas the urethra and cervix are very rare. To the best of our knowledge, this is the first report on concurrent extranodal involvement of the uterine cervix and urethra. We report imaging findings of malignant lymphoma involving urethra and cervix concurrently in a 79-year-old female patient with literature review. The magnetic resonance imaging showed huge intermediate to high signal intensity mass on T2 weighted images and strong homogeneous enhancement in uterine cervix and periurethral area, but no surrounding architectural disruption.

Interobserver agreement in breast ultrasound categorization in the Mammography and Ultrasonography Study for Breast Cancer Screening Effectiveness (MUST-BE) trial: results of a preliminary study

PURPOSE: The purpose of this study was to record and evaluate interobserver agreement as quality control for the modified categorization of screening breast ultrasound developed by the Alliance for Breast Cancer Screening in Korea (ABCS-K) for the Mammography and Ultrasonography Study for Breast Cancer Screening Effectiveness (MUST-BE) trial. METHODS: Eight breast radiologists with 4-16 years of experience participated in 2 rounds of quality control testing for the MUST-BE trial. Two investigators randomly selected 125 and 100 cases of breast lesions with different ratios of malignant and benign lesions. Two versions of the modified categorization were tested. The initially modified classification was developed after the first quality control workshop, and the re-modified classification was developed after the second workshop. The re-modified categorization established by ABCS-K added size criteria and the anterior-posterior ratio compared with the initially modified classification. After a brief lecture on the modified categorization system prior to each quality control test, the eight radiologists independently categorized the lesions using the modified categorization. Interobserver agreement was measured using kappa statistics. RESULTS: The overall kappa values for the modified categorizations indicated moderate to substantial degrees of agreement (initially modified categorization and re-modified categorization: κ=0.52 and κ=0.63, respectively). The kappa values for the subcategories of category 4 were 0.37 (95% confidence interval [CI], 0.24 to 0.52) and 0.39 (95% CI, 0.31 to 0.49), respectively. The overall kappa values for both the initially modified categorization and the re-modified categorization indicated a substantial degree of agreement when dichotomizing the interpretation as benign or suspicious. CONCLUSION: The preliminary results demonstrated acceptable interobserver agreement for the modified categorization.

Effect of Different Types of Mammography Equipment on Screening Outcomes: A Report by the Alliance for Breast Cancer Screening in Korea

OBJECTIVE: To investigate the effects of different types of mammography equipment on screening outcomes by comparing the performance of film-screen mammography (FSM), computed radiography mammography (CRM), and digital mammography (DM).MATERIALS AND METHODS: We retrospectively enrolled 128756 sets of mammograms from 10 hospitals participating in the Alliance for Breast Cancer Screening in Korea between 2005 and 2010. We compared the diagnostic accuracy of the types of mammography equipment by analyzing the area under the receiver operating characteristic curve (AUC) with a 95% confidence interval (CI); performance indicators, including recall rate, cancer detection rate (CDR), positive predictive value₁ (PPV₁), sensitivity, specificity, and interval cancer rate (ICR); and the types of breast cancer pathology.RESULTS: The AUCs were 0.898 (95% CI, 0.878–0.919) in DM, 0.860 (0.815–0.905) in FSM, and 0.866 (0.828–0.903) in CRM (p = 0.150). DM showed better performance than FSM and CRM in terms of the recall rate (14.8 vs. 24.8 and 19.8%), CDR (3.4 vs. 2.2 and 2.1 per 1000 examinations), PPV₁ (2.3 vs. 0.9 and 1.1%), and specificity (85.5 vs. 75.3 and 80.3%) (p < 0.001) but not in terms of sensitivity (86.3 vs. 87.4 and 86.3%) and ICR (0.6 vs. 0.4 and 0.4). The proportions of carcinoma in situ (CIS) were 27.5%, 13.6%, and 11.8% for DM, CRM, and FSM, respectively (p = 0.003).CONCLUSION: In comparison to FSM and CRM, DM showed better performance in terms of the recall rate, CDR, PPV₁, and specificity, although the AUCs were similar, and more CISs were detected using DM. The application of DM may help to improve the quality of mammography screenings. However, the overdiagnosis issue of CIS using DM should be evaluated.

Interpretive Performance and Inter-Observer Agreement on Digital Mammography Test Sets

OBJECTIVE: To evaluate the interpretive performance and inter-observer agreement on digital mammographs among radiologists and to investigate whether radiologist characteristics affect performance and agreement. MATERIALS AND METHODS: The test sets consisted of full-field digital mammograms and contained 12 cancer cases among 1000 total cases. Twelve radiologists independently interpreted all mammograms. Performance indicators included the recall rate, cancer detection rate (CDR), positive predictive value (PPV), sensitivity, specificity, false positive rate (FPR), and area under the receiver operating characteristic curve (AUC). Inter-radiologist agreement was measured. The reporting radiologist characteristics included number of years of experience interpreting mammography, fellowship training in breast imaging, and annual volume of mammography interpretation. RESULTS: The mean and range of interpretive performance were as follows: recall rate, 7.5% (3.3–10.2%); CDR, 10.6 (8.0–12.0 per 1000 examinations); PPV, 15.9% (8.8–33.3%); sensitivity, 88.2% (66.7–100%); specificity, 93.5% (90.6–97.8%); FPR, 6.5% (2.2–9.4%); and AUC, 0.93 (0.82–0.99). Radiologists who annually interpreted more than 3000 screening mammograms tended to exhibit higher CDRs and sensitivities than those who interpreted fewer than 3000 mammograms (p = 0.064). The inter-radiologist agreement showed a percent agreement of 77.2–88.8% and a kappa value of 0.27–0.34. Radiologist characteristics did not affect agreement. CONCLUSION: The interpretative performance of the radiologists fulfilled the mammography screening goal of the American College of Radiology, although there was inter-observer variability. Radiologists who interpreted more than 3000 screening mammograms annually tended to perform better than radiologists who did not.

Low-Tube-Voltage CT Urography Using Low-Concentration-Iodine Contrast Media and Iterative Reconstruction: A Multi-Institutional Randomized Controlled Trial for Comparison with Conventional CT Urography

OBJECTIVE: To compare the image quality of low-tube-voltage and low-iodine-concentration-contrast-medium (LVLC) computed tomography urography (CTU) with iterative reconstruction (IR) with that of conventional CTU. MATERIALS AND METHODS: This prospective, multi-institutional, randomized controlled trial was performed at 16 hospitals using CT scanners from various vendors. Patients were randomly assigned to the following groups: 1) the LVLC-CTU (80 kVp and 240 mgI/mL) with IR group and 2) the conventional CTU (120 kVp and 350 mgI/mL) with filtered-back projection group. The overall diagnostic acceptability, sharpness, and noise were assessed. Additionally, the mean attenuation, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and figure of merit (FOM) in the urinary tract were evaluated. RESULTS: The study included 299 patients (LVLC-CTU group: 150 patients; conventional CTU group: 149 patients). The LVLC-CTU group had a significantly lower effective radiation dose (5.73 ± 4.04 vs. 8.43 ± 4.38 mSv) compared to the conventional CTU group. LVLC-CTU showed at least standard diagnostic acceptability (score ≥ 3), but it was non-inferior when compared to conventional CTU. The mean attenuation value, mean SNR, CNR, and FOM in all pre-defined segments of the urinary tract were significantly higher in the LVLC-CTU group than in the conventional CTU group. CONCLUSION: The diagnostic acceptability and quantitative image quality of LVLC-CTU with IR are not inferior to those of conventional CTU. Additionally, LVLC-CTU with IR is beneficial because both radiation exposure and total iodine load are reduced.

Ultrasonographic and Pathologic Findings of Dermatofibrosarcoma Protuberans of the Breast: A Case Report

Dermatofibrosarcoma protuberans (DFSP) is a rare, malignant soft tissue tumor. It arises from the dermis, however, a few lesions are known to infiltrate into deeper layers. It commonly occurs on the trunk and extremities, but rarely involves the breast. We report a case of a 43-year-old woman who had histologically proven DFSP of the breast, with emphasis on ultrasonographic findings and pathological features. In our case, the ultrasonographic features of DFSP revealed an ovalshaped hypoechoic mass in the dermis of left breast with surrounded by increased levels of echogenic subcutaneous fat. This ultrasonographic finding correlated with pathologic features of infiltration of tumor cells into the subcutaneous fat. No previous study reported this feature of DFSP associated with the breast.

Periductal Stromal Sarcoma of the Breast: a Case Report

Periductal stromal sarcoma (PSS) is a type of rare malignant fibroepithelial tumor. PSS is a recently introduced diagnostic entity and there are few reports about radiological features of this tumor. Pre-operative diagnosis is difficult because it reveals similar symptoms with other benign and malignant tumors with absence of specific radiologic findings. We present a woman age 30 that underwent mammotome biopsy for a BI-RADS 4 lesion on her left breast and received histopathology diagnosis of a phyllodes tumor. Additionally, she underwent a wide excision depending on her histopathology diagnosis. Her final diagnosis was PSS. Six months later, no recurrence was detected. However, frequent follow-up is needed because PSS can develop into phyllodes tumor or entity of breast cancer.

Validation of the fifth edition BI-RADS ultrasound lexicon with comparison of fourth and fifth edition diagnostic performance using video clips

PURPOSE: The aim of this study was to evaluate the positive predictive value (PPV) and the diagnostic performance of the ultrasonographic descriptors in the fifth edition of BI-RADS, comparing with the fourth edition using video clips. METHODS: From September 2013 to July 2014, 80 breast masses in 74 women (mean age, 47.5±10.7 years) from five institutions of the Korean Society of Breast Imaging were included. Two radiologists individually reviewed the static and video images and analyzed the images according to the fourth and fifth edition of BI-RADS. The PPV of each descriptor was calculated and diagnostic performances between the fourth and fifth editions were compared. RESULTS: Of the 80 breast masses, 51 (63.8%) were benign and 29 (36.2%) were malignant. Suspicious ultrasonographic features such as irregular shape, non-parallel orientation, angular or spiculated margins, and combined posterior features showed higher PPV in both editions (all P0.05). The area under the receiver operating characteristics curve was higher in the fourth edition (0.708 to 0.690), without significance (P=0.416). CONCLUSION: The fifth edition of the BI-RADS ultrasound lexicon showed comparable performance to the fourth edition and can be useful in the differential diagnosis of breast masses using ultrasonography.

Comparison of needle aspiration and vacuum-assisted biopsy in the ultrasound-guided drainage of lactational breast abscesses

PURPOSE: The purpose of this study was to compare needle aspiration and vacuum-assistedbiopsy in the ultrasound-guided treatment of lactational breast abscesses. METHODS: Between January 2005 and December 2014, a total of 74 patients presented withlactational breast abscesses. Thirty of these patients underwent treatment with antibioticsalone, while the remaining 44 lactating women with breast abscesses were treated withneedle aspiration (n=25) or vacuum-assisted biopsy (n=19). Age, duration of lactation, abscess diameter, pus culture results, the number of interventions, the healing time, and the cure rate were reviewed and compared between these two groups. The Student's t test and the chi-square test were used to compare the variables. RESULTS: No significant difference was found in the cure rate between the needle aspirationgroup (22/25, 88%) and the vacuum-assisted biopsy group (18/19, 94.7%) (P=0.441). However, the mean healing time was significantly shorter in the vacuum-assisted biopsy group (6.7 days) than in the needle aspiration group (9.0 days) (P=0.001). CONCLUSION: Vacuum-assisted biopsy is a viable option for the management of lactational breast abscesses and was found to lead to a shorter healing time than needle aspiration. However, further study is necessary to establish the clinical efficacy of vacuum-assisted biopsy in the management of lactational breast abscesses.

Performance of Screening Mammography: A Report of the Alliance for Breast Cancer Screening in Korea

OBJECTIVE: To analyze the diagnostic accuracy and trend in screening mammography in Korea. MATERIALS AND METHODS: We retrospectively linked the information from hospitals participating in the Alliance of Breast Cancer Screening in Korea (ABCS-K) and the database of the National Cancer Screening Program. We calculated performance indicators, including the recall rate, cancer detection rate (CDR), positive predictive value (PPV), sensitivity, specificity, false-positive rate (FPR), and interval cancer rate (ICR). Changes in the performance indicators were calculated as the annual percent change with 95% confidence interval (CI). RESULTS: We enrolled 128756 cases from 10 hospitals from 2005 to 2010. The recall rate was 19.1% with a downward trend over time (-12.1% per year; 95% CI, -15.9 to -8.2). The CDR was 2.69 per 1000 examinations, without a significant trend. The PPV was 1.4% with an upward trend (20.8% per year; 95% CI, 15.2 to 26.7). The sensitivity was 86.5% without a significant trend, whereas the specificity was 81.1% with an upward trend (3.3% per year; 95% CI, 2.1 to 4.5). The FPR was 18.9% with a downward trend (-12.4% per year; 95% CI, -16.2 to -8.4). The ICR was 0.5 per 1000 negative examinations without a significant trend. There were institutional variations in the diagnostic accuracy and trend except for the CDR, sensitivity, and ICR. CONCLUSION: The sensitivity and CDR of screening mammography in the ABCS-K from 2005 to 2010 were compatible with those for Western women. The recall rate, PPV and specificity, however, were suboptimal, although they showed significant improvements over this period. A further analysis is required to explain institutional variations.

Colonic Metastasis Presenting as an Intraluminal Fungating Mass 8 Years After Surgery for Ovarian Cancer

We report a case of colonic metastasis from ovarian cancer presented as an intraluminal fungating mass mimicking primary colon cancer 8 years after surgery for ovarian cancer. A 70-year-old woman presented with constipation. She had undergone an extended total abdominal hysterectomy with bilateral salpingo-oophorectomy for an ovarian papillary serous cystadenocarcinoma 8 years earlier. Colonoscopy showed a large fungating mass 10 cm from the anal verge that was suspected to be colorectal cancer. A computed tomography scan showed a bulky intraluminal fungating mass in the rectosigmoid junction. After a lower anterior resection and a pathologic diagnosis, a diagnosis of a papillary serous adenocarcinoma due to metastasis from an ovarian tumor was made for this patient.

The Efficacy of Mammography Boot Camp to Improve the Performance of Radiologists

OBJECTIVE: To evaluate the efficacy of a mammography boot camp (MBC) to improve radiologists' performance in interpreting mammograms in the National Cancer Screening Program (NCSP) in Korea. MATERIALS AND METHODS: Between January and July of 2013, 141 radiologists were invited to a 3-day educational program composed of lectures and group practice readings using 250 digital mammography cases. The radiologists' performance in interpreting mammograms were evaluated using a pre- and post-camp test set of 25 cases validated prior to the camp by experienced breast radiologists. Factors affecting the radiologists' performance, including age, type of attending institution, and type of test set cases, were analyzed. RESULTS: The average scores of the pre- and post-camp tests were 56.0 +/- 12.2 and 78.3 +/- 9.2, respectively (p 0.05). CONCLUSION: The MBC improves radiologists' performance in interpreting mammograms irrespective of age and type of attending institution. Improved interpretation is observed for suspicious cases, but not for negative cases.

Characteristics of the Germline MEN1 Mutations in Korea: A Literature Review / 대한내분비외과학회지

PURPOSE: Multiple endocrine neoplasia type 1 (MEN-1) is an autosomal dominant disease caused by the MEN1 germline mutation. We reviewed previous reports in order to summarize the characteristics of germline MEN1 mutation in Korea. METHODS: We retrieved the relevant literature regarding MEN1 germline mutation in Korea using the Pubmed (http://www.pubmed.org/) and Koreamed (http://www.koreamed.org/) databases from 2000 to 2012. We evaluated the pedigree of the patients in order to exclude the same, repeated families. We collected all data on the types of mutations and clinical characteristics. RESULTS: There were nine studies with 12 cases of MEN1 mutations in Korea. Two cases were sporadic MEN-1. C.196_200dupAGCCC was reported in three families. There were six cases of frameshift mutation, three cases of missense mutation, two cases of nonsense mutation, and one case of splice site mutation. Five mutations were novel mutations not previously reported. CONCLUSION: We summarized the characteristics of germline MEN1 mutations in Korea. Genetic testing of MEN1 is rare in Korea; however, it will be useful in preclinical diagnosis and genetic counseling.

Bromocriptine-Treated Giant Lactating Adenoma: A Case Report with Imaging Findings

Lactating adenoma is a benign breast disease that occurs during pregnancy or lactational periods. Here we report on a case of rapidly enlarging lactating adenoma in a 28-year-old postpartum woman, which was mistaken for a malignant breast tumor. Treatment with bromocriptine resulted in a rapid reduction of the mass, suggesting that bromocriptine could be used for shrinking lactating adenoma and to facilitate surgical removal. We describe its imaging findings, including ultrasonographic findings with correlative histologic features, confirmed by surgical excision.

Immunopathogenesis of Allergic Asthma: More Than the Th2 Hypothesis

Asthma is a chronic obstructive airway disease that involves inflammation of the respiratory tract. Biological contaminants in indoor air can induce innate and adaptive immune responses and inflammation, resulting in asthma pathology. Epidemiologic surveys indicate that the prevalence of asthma is higher in developed countries than in developing countries. The prevalence of asthma in Korea has increased during the last several decades. This increase may be related to changes in housing styles, which result in increased levels of indoor biological contaminants, such as house dust mite-derived allergens and bacterial products such as endotoxin. Different types of inflammation are observed in those suffering from mild-to-moderate asthma compared to those experiencing severe asthma, involving markedly different patterns of inflammatory cells and mediators. As described in this review, these inflammatory profiles are largely determined by the involvement of different T helper cell subsets, which orchestrate the recruitment and activation of inflammatory cells. It is becoming clear that T helper cells other than Th2 cells are involved in the pathogenesis of asthma; specifically, both Th1 and Th17 cells are crucial for the development of neutrophilic inflammation in the airways, which is related to corticosteroid resistance. Development of therapeutics that suppress these immune and inflammatory cells may provide useful asthma treatments in the future.

Estimating the Risks and Benefits of Tamoxifen for Prophylactic Breast Cancer Chemoprevention in Korea / 한국유방암학회지

PURPOSE: According to the National Surgical Adjuvant Breast and Bowel Project P1 (NSABP-P1) study, tamoxifen can prevent 49% of invasive breast cancers in patients who have a 5-year risk of 1.67% or more. Because tamoxifen is associated with both adverse effects (endometrial cancer, stroke, pulmonary embolism) and protective effect (fracture prevention), it is necessary to weigh the risks and benefits of using tamoxifen for prevention in Korean women. This study weighed those risks and benefits. METHODS: Data were reviewed on the incidences of breast cancer, hip fracture, endometrial cancer and stroke in the absence of tamoxifen treatment in Korean women. We also reviewed NSABP-P1 data on the effects of tamoxifen on these outcomes. A risk-benefit index was calculated according to age and specific risk of breast cancer. Sensitivity analyses were performed with assumptions regarding the effects of tamoxifen. RESULTS: Compared to U.S. women, the numbers of hip fractures and endometrial cancers were lower, but the number of strokes was much higher. The net benefit of tamoxifen was reduced with increasing age because of a high risk of stroke in older women. Older Korean women had more risk than benefit from tamoxifen chemoprevention. Only women younger than age 40 had a positive risk-benefit index with an average 5-year risk of breast cancer in Korea. Sensitivity analysis showed that this result was robust. CONCLUSION: Women under the age 40 had more benefit than risk from tamoxifen chemoprevention. Tamoxifen chemoprevention should be limited to Korean women younger than age 40.

Estimating the Risks and Benefits of Tamoxifen for Prophylactic Breast Cancer Chemoprevention in Korea / 한국유방암학회지

PURPOSE: According to the National Surgical Adjuvant Breast and Bowel Project P1 (NSABP-P1) study, tamoxifen can prevent 49% of invasive breast cancers in patients who have a 5-year risk of 1.67% or more. Because tamoxifen is associated with both adverse effects (endometrial cancer, stroke, pulmonary embolism) and protective effect (fracture prevention), it is necessary to weigh the risks and benefits of using tamoxifen for prevention in Korean women. This study weighed those risks and benefits. METHODS: Data were reviewed on the incidences of breast cancer, hip fracture, endometrial cancer and stroke in the absence of tamoxifen treatment in Korean women. We also reviewed NSABP-P1 data on the effects of tamoxifen on these outcomes. A risk-benefit index was calculated according to age and specific risk of breast cancer. Sensitivity analyses were performed with assumptions regarding the effects of tamoxifen. RESULTS: Compared to U.S. women, the numbers of hip fractures and endometrial cancers were lower, but the number of strokes was much higher. The net benefit of tamoxifen was reduced with increasing age because of a high risk of stroke in older women. Older Korean women had more risk than benefit from tamoxifen chemoprevention. Only women younger than age 40 had a positive risk-benefit index with an average 5-year risk of breast cancer in Korea. Sensitivity analysis showed that this result was robust. CONCLUSION: Women under the age 40 had more benefit than risk from tamoxifen chemoprevention. Tamoxifen chemoprevention should be limited to Korean women younger than age 40.

Brain-in-Brain Artifact (BIBA) in a Patient with Hydranencepaly: A Case Report

Hydranencephaly is a condition that is characterized by an absent brain mantle along with the subadjacent white matter, with replacement of the cerebral hemispheres by a thin-walled membranous sac containing CSF. During brain sonograpy in a neonate with hydranencephaly, we have found a brain-in-brain appearance as an unusual sonographic artifact. We report here on this interesting sonographic artifact in a neonate with hydranencephaly, and this artifact was due to multipath reflection artifact of the ultrasound beam/wave, and we explain the underlying physics.