Malignant Apocrine Lesions of the Breast: Multimodality Imaging Findings and Biologic Features / 한국유방암학회지

The apocrine morphology of the breast is observed in a broad pathological spectrum, ranging from benign cysts to invasive carcinomas. However, the number of clinical research investigating malignant apocrine lesions is limited. This study retrospectively reviewed the data of patients with malignant apocrine lesions admitted in a tertiary center between January 2004 and December 2021, based on the radiology-pathology correlation and the recent advances in their status to enhance the therapeutic implications of androgen receptor (AR). Among the 37 patients with lesions, 27 (73.0%) had triple-negative subtypes with predominant AR expression. The radiological features of malignant apocrine lesions did not differ from those of typical invasive ductal carcinoma or ductal carcinoma in situ. This study demonstrated that knowledge on the imaging features of malignant apocrine lesions and their histological basis could enhance the adoption of new targeted therapies in patients with this particular type of breast cancer.

Invasive Ductal Carcinoma Originating from a Borderline Phyllodes Tumor in a Young Female: A Case Report

Phyllodes tumors of the breast are relatively rare fibroepithelial tumors that account for less than 1% of primary breast neoplasms. Phyllodes tumors have epithelial and stromal components and they originate from the periductal stroma. They are classified as benign, borderline, or malignant. Carcinomatous differentiation of the epithelial components of phyllodes tumors is rare, and their imaging features have not been accurately described. Herein, we report a rare case of invasive ductal carcinoma originating from a borderline phyllodes tumor in a 21-yearold female with radiologic and pathologic findings.

Tumor Seeding after Percutaneous Transthoracic Needle Biopsy of Metastatic Pulmonary Ameloblastoma

Percutaneous transthoracic needle biopsy (PTNB) is a minimally-invasive procedure that is an indispensable tool for evaluating pulmonary lesions. Though extremely rare, tumor seeding of the pleura and chest wall can occur as a complication. Given that the breast is located anterior to the thorax, needle tracking through the breast is inevitable when PTNB is performed using the anterior approach. We describe tumor seeding of metastatic pulmonary ameloblastoma in the pectoralis muscle layer of the breast along the needle track of PTNB in a 51-year-old female presenting with a palpable lump in the right breast.

Pictorial Review of Mediastinal Masses with an Emphasis on Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) has become a crucial tool for evaluating mediastinal masses considering that several lesions that appear indeterminate on computed tomography and radiography can be differentiated on MRI. Using a three-compartment model to localize the mass and employing a basic knowledge of MRI, radiologists can easily diagnose mediastinal masses. Here, we review the use of MRI in evaluating mediastinal masses and present the images of various mediastinal masses categorized using the International Thymic Malignancy Interest Group’s three-compartment classification system. These masses include thymic hyperplasia, thymic cyst, pericardial cyst, thymoma, mediastinal hemangioma, lymphoma, mature teratoma, bronchogenic cyst, esophageal duplication cyst, mediastinal thyroid carcinoma originating from ectopic thyroid tissue, mediastinal liposarcoma, mediastinal pancreatic pseudocyst, neurogenic tumor, meningocele, and plasmacytoma.

Invasive Ductal Carcinoma Originating from a Borderline Phyllodes Tumor in a Young Female: A Case Report

Phyllodes tumors of the breast are relatively rare fibroepithelial tumors that account for less than 1% of primary breast neoplasms. Phyllodes tumors have epithelial and stromal components and they originate from the periductal stroma. They are classified as benign, borderline, or malignant. Carcinomatous differentiation of the epithelial components of phyllodes tumors is rare, and their imaging features have not been accurately described. Herein, we report a rare case of invasive ductal carcinoma originating from a borderline phyllodes tumor in a 21-yearold female with radiologic and pathologic findings.

Tumor Seeding after Percutaneous Transthoracic Needle Biopsy of Metastatic Pulmonary Ameloblastoma

Percutaneous transthoracic needle biopsy (PTNB) is a minimally-invasive procedure that is an indispensable tool for evaluating pulmonary lesions. Though extremely rare, tumor seeding of the pleura and chest wall can occur as a complication. Given that the breast is located anterior to the thorax, needle tracking through the breast is inevitable when PTNB is performed using the anterior approach. We describe tumor seeding of metastatic pulmonary ameloblastoma in the pectoralis muscle layer of the breast along the needle track of PTNB in a 51-year-old female presenting with a palpable lump in the right breast.

Atypical Hyperplasia at the Margin of Frozen Sections from Breast-Conserving Surgery

Purpose@#Intraoperative frozen section analysis to assess margin status during breast-conserving surgery is often performed to reduce the rate of re-excision. Whether additional resection is required if atypical cells are found at the margin during breast-conserving surgery is controversial. The aim of this study was to evaluate the accuracy of intraoperative frozen section analysis and investigate the feasibility of additional resection in cases of atypical hyperplasia on frozen sections from breast-conserving surgery. @*Methods@#A retrospective analysis was performed on 1,411 patients with invasive breast cancer who underwent breast-conserving surgery between July 2004 and June 2012. The microscopic margins of the intraoperative frozen sections and permanent sections were examined. Overall events (locoregional recurrence and distant metastasis) were analyzed between the negative margin group and the other margin group (including atypical hyperplasia, carcinoma in situ [CIS], and invasive carcinoma). @*Results@#Of the 1,411 patients, 1,201 had negative margins and 210 had other margin types in the first frozen section. 68 patients had atypical hyperplasia on frozen section analysis. This atypical hyperplasia included atypical cells, atypical ductal hyperplasia, and atypical lobular hyperplasia. Of these 68 patients, the final findings on the permanent section were negative (n=32, 47.1%), atypical cells (n=16, 23.5%), and CIS (n=20, 29.4%). The rate of overall events and distant metastases were higher in the other margin group (9.5% vs. 5.4%, p=0.021) and (5.7% vs. 3.0%, p=0.045). Of the 1,411 patients, 44 (3.1%) had false-positive findings, and 15 (1.1%) had false-negative findings in the frozen sections, with an accuracy of 95.8%. @*Conclusion@#The accuracy of intraoperative frozen section analysis was 95.8%, with 91.7% sensitivity and 96.4% specificity. Atypical hyperplasia on frozen section analysis requires additional resection at the time of breast-conserving surgery because of the possibility of CIS, but excessive resection may be performed in other cases. Therefore, sufficient consultation with patients is required.

Nipple Adenoma Treated with Nipple Preservation in Young Female Patient: A Report of 2 Cases

Adenoma of the nipple is a rare benign type of breast that occurs most often in middle-aged women with nipple discharge, skin erosion in addition to crusting, inflammation, and pain. It can be clinically confused with Paget’s disease or breast cancer precursor lesions, such as ductal carcinoma in situ low grade. The treatment of choice for nipple adenoma is complete excision of the tumor. However in younger women, nipple preservation is required. We present two cases of nipple adenoma that were completely removed with nipple preservation.

Cutaneous Scalp Metastases of Malignant Phyllodes Tumor of the Breast / 한국유방암학회지

Phyllodes tumor (PT) of the breast is a relatively rare fibroepithelial tumor that accounts for < 1% of primary breast neoplasms. PT is classified histologically as benign, borderline, or malignant, and a malignant PT has greater potential to metastasize than benign PT.Although almost all other organs can be affected, common metastatic sites are the lung and bone via the hematogenous route. There have been several studies reporting cutaneous and soft tissue metastases of PT, though the incidence is rare. Herein, we report a very rare case of scalp metastasis of malignant PT that was diagnosed via skin biopsy and surgical excision.

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.

Incidental, Small (< 3 cm), Unilocular, Pancreatic Cysts: Factors That Predict Lesion Progression during Imaging Surveillance

OBJECTIVE: To explore the features that predict size increase and development of potential malignant features in incidentally detected, unilocular cystic pancreatic lesions (CPLs) less than 3 cm in diameter, during subsequent follow-up. MATERIALS AND METHODS: We retrieved data of patients diagnosed with unilocular CPLs less than 3 cm in diameter during the period from November 2003 through December 2014, using a computerized search. All serial CT and MR images were analyzed to identify the number, size, and location of CPLs; dilatation of the main pancreatic duct; and occurrence of worrisome features and high-risk stigmata of malignancy in the lesion. The characteristics of CPLs were compared between the increase (i.e., size increase during subsequent follow-up) and no-increase groups. For CPLs in the increase group, subgroup analysis was performed according to the lesion size at the last follow-up (< 3 cm vs. ≥ 3 cm). RESULTS: Among 553 eligible patients, 132 (23.9%) had CPLs that increased in size, and 421 (76.1%) had CPLs that did not, during follow-up. Of the 132, 12 (9.1%) CPLs increased to diameters ≥ 3 cm at the final follow-up. Among the various factors, follow-up duration was a significant independent factor for an interval size increase of CPLs (p < 0.001). In the increase group, initial cyst size was a significant independent factor to predict later size increase to or beyond 3 cm in diameter (p < 0.001), and the initial cyst diameter ≥ 1.5 cm predicted such a growth with a sensitivity and specificity of 83% and 72%, respectively. No significant factors to predict the development of potential malignant features were identified. CONCLUSION: Follow-up duration was associated with an interval size increase of CPLs. Among the growing CPLs, initial cyst size was associated with future lesion growth to and beyond 3 cm.

Analysis of Participant Factors That Affect the Diagnostic Performance of Screening Mammography: A Report of the Alliance for Breast Cancer Screening in Korea

OBJECTIVE: To analyze participant factors that affect the diagnostic performance of screening mammography. MATERIALS AND METHODS: We enrolled 128756 cases from 10 hospitals between 2005 and 2010. We analyzed recall rate, cancer detection rate (CDR) per 1000 examinations, positive predictive value (PPV), sensitivity, specificity, false positive rate (FPR), and interval cancer rate (ICR) per 1000 negative examinations according to participant factors including age, breast density, and number of visit to the same institution, and adjusted for confounding variables. RESULTS: Increasing age improved recall rates (27.4% in 40's, 17.5% in 50's, 11.1% in 60's, and 8.6% in 70's), CDR (2.7, 3.2, 2.0, and 2.4), PPV (1.0, 1.8, 1.8, and 2.8%), sensitivity (81.3, 88.8, 90.3, and 94.7%), specificity (72.7, 82.7, 89.0, and 91.7%), and FPR (27.3, 17.3, 11.0, and 8.4%) (p < 0.05). Higher breast density impaired recall rates (4.0% in P1, 9.0% in P2, 28.9% in P3, and 27.8% in P4), PPV (3.3, 2.3, 1.2, and 1.3%), specificity (96.1, 91.2, 71.4, and 72.5%), and FPR (3.9, 8.9, 28.6, and 27.6%) (p < 0.001). It also increased CDR (1.3, 2.1, 3.3, and 3.6) and ICR (0.2, 0.3, 0.6, and 1.6) (p < 0.05). Successive visits to the same institution improved recall rates (20.9% for one visit, 10.7% for two visits, 7.7% for more than three visits), PPV (1.6, 2.8, and 2.7%), specificity (79.4, 89.6, and 92.5%), and FPR (20.6, 10.4, and 7.5%) (p < 0.001). CONCLUSION: Young age and dense breasts negatively affected diagnostic performance in mammography screening, whereas successive visits to the same institution had a positive effect. Examinee education for successive visits to the same institution would improve the diagnostic performance.

Invasive Micropapillary Carcinoma in Axillary Ectopic Breast and Synchronous Ductal Carcinoma In Situ in the Contralateral Breast / 한국유방암학회지

The development of ectopic breast tissue is attributable to the failure of primitive mammary tissue to regress after the development of the mammary ridge, except at pectoral breast sites, and is most often evident in the axillae. Several benign and malignant breast diseases have been reported in ectopic axillary breast tissues. The most common cancerous pathology of ectopic breast tissue is invasive ductal carcinoma. Ectopic breast cancer presenting with simultaneous primary cancer of the pectoral breast is extremely rare. Herein, we report an invasive micropapillary carcinoma of an axillary ectopic breast, combined with a synchronous ductal carcinoma in situ in the contralateral pectoral breast of a 61-year-old woman.

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.

Incidental Breast Lesions Identified by 18F-FDG PET/CT: Which Clinical Variables Differentiate between Benign and Malignant Breast Lesions? / 한국유방암학회지

PURPOSE: The aim of our study was to evaluate the risk of malignancy and to determine which clinical variables differentiate between benign and malignant focal breast lesions found incidentally on 18F-flourodeoxyglucose positron emission tomography and computed tomography (FDG PET/CT). METHODS: From March 2005 to October 2011, 21,224 women with no history of breast cancer underwent FDG PET/CT at three university-affiliated hospitals. We retrospectively identified 214 patients with incidental focal hypermetabolic breast lesions and grouped them into benign and malignant lesion groups. Of the 214 patients, 82 patients with 91 lesions were included in this study. All lesions were confirmed histologically or were assessed by follow-up imaging for greater than 2 years. The patient age, maximum standardized uptake value (SUVmax), lesion size on ultrasonography (US), and Breast Imaging-Reporting and Data System (BI-RADS) category on US in conjunction with mammography were compared between the groups. Multivariate logistic regression analysis was used to identify independent factors associated with malignancy. RESULTS: The risk of malignancy was 29.7% (27/91) in breast incidentalomas detected by FDG PET/CT. The univariate analysis showed that the patient age, SUVmax, tumor size, and BI-RADS category differed significantly between the malignant and benign groups. The multivariate analysis showed that the BI-RADS category was the only significant factor differentiating benign from malignant lesions (p=0.002). CONCLUSION: BIRADS category based on US in conjunction with mammography was the only useful tool to differentiate between malignant and benign lesions in breast incidentalomas on FDG PET/CT.

Ultrasound-Guided Percutaneous Radiofrequency Ablation of Liver Tumors: How We Do It Safely and Completely

Ultrasound-guided percutaneous radiofrequency (RF) ablation has become one of the most promising local cancer therapies for both resectable and nonresectable hepatic tumors. Although RF ablation is a safe and effective technique for the treatment of liver tumors, the outcome of treatment can be closely related to the location and shape of the tumors. There may be difficulties with RF ablation of tumors that are adjacent to large vessels or extrahepatic heat-vulnerable organs and tumors in the caudate lobe, possibly resulting in major complications or treatment failure. Thus, a number of strategies have been developed to overcome these challenges, which include artificial ascites, needle track ablation, fusion imaging guidance, parallel targeting, bypass targeting, etc. Operators need to use the right strategy in the right situation to avoid the possibility of complications and incomplete thermal tissue destruction; with the right strategy, RF ablation can be performed successfully, even for hepatic tumors in high-risk locations. This article offers technical strategies that can be used to effectively perform RF ablation as well as to minimize possible complications related to the procedure with representative cases and schematic illustrations.

The Role of Three-Dimensional Multidetector CT Gastrography in the Preoperative Imaging of Stomach Cancer: Emphasis on Detection and Localization of the Tumor

Multidetector CT (MDCT) gastrography has been regarded as a promising technique for the preoperative imaging of gastric cancer. It has the ability to produce various three-dimensional (3D) images. Because 3D reconstruction images are more effective and intuitive for recognizing abnormal changes in the gastric folds and subtle mucosal nodularity than two-dimensional images, 3D MDCT gastrography can enhance the detection rate of early gastric cancer, which, in turn, contributes to the improvement of the accuracy of preoperative tumor (T) staging. In addition, shaded surface display and tissue transition projection images provide a global view of the stomach, with the exact location of gastric cancer, which may replace the need for barium studies. In this article, we discuss technical factors in producing high-quality MDCT gastrographic images and present cases demonstrating the usefulness of MDCT gastrography for the detection and T staging of gastric cancer while emphasizing the significance of preoperative localization of gastric cancer in terms of surgical margin.

Hepatic Arterial Phase on Gadoxetic Acid-Enhanced Liver MR Imaging: A Randomized Comparison of 0.5 mL/s and 1 mL/s Injection Rates

OBJECTIVE: To compare gadoxetic acid injection rates of 0.5 mL/s and 1 mL/s for hepatic arterial-phase magnetic resonance (MR) imaging. MATERIALS AND METHODS: In this prospective study, 101 consecutive patients with suspected focal liver lesions were included and randomly divided into two groups. Each group underwent dynamic liver MR imaging using a 3.0-T scanner after an intravenous injection of gadoxetic acid at rates of either 0.5 mL/s (n = 50) or 1 mL/s (n = 51). Arterial phase images were analyzed after blinding the injection rates. The signal-to-noise ratios (SNRs) of the liver, aorta, portal vein, hepatic vein, spleen, and pancreas were measured. The contrast-to-noise ratios (CNRs) of the hepatocellular carcinomas (HCC) were calculated. Finally, two experienced radiologists were independently asked to identify, if any, HCCs in the liver on the images and score the image quality in terms of the presence of artifacts and the proper enhancement of the liver, aorta, portal vein, hepatic vein, hepatic artery, spleen, pancreas, and kidney. RESULTS: The SNRs were not significantly different between the groups (p = 0.233-0.965). The CNRs of the HCCs were not significantly different (p = 0.597). The sensitivity for HCC detection and the image quality scores were not significantly different between the two injection rates (p = 0.082-1.000). CONCLUSION: Image quality and sensitivity for hepatic HCCs of arterial-phase gadoxetic acid-enhanced MR were not significantly improved by reducing the contrast injection rate to 0.5 mL/s compared with 1 mL/s.

Atypia of undetermined significance on thyroid fine needle aspiration: surgical outcome and risk factors for malignancy

PURPOSE: This study was performed to analyze the surgical pathology results of the "atypia of undetermined significance" (AUS) category from thyroid fine needle aspiration (FNA) and to describe the characteristics to distinguish a malignant from a benign nodule. METHODS: A retrospective analysis was done on 116 patients who underwent thyroid surgery from December 2008 to December 2012, following a diagnosis of AUS from preoperative thyroid FNA. We investigated the age, gender, size and site of the nodules, ultrasonographic criteria, cytological features, the number of atypia results after repeated FNAs, surgical method, and final pathologic results. RESULTS: Sixty-five out of 116 patients underwent total thyroidectomy and the rest had partial thyroidectomy. The final pathologic results were 41 malignancies (35.3%) and 75 benign diseases (64.7%). AUS was divided into group 1: 'cannot rule out malignancy' or group 2: 'cannot rule out follicular neoplasm'. After surgery, group 1 revealed papillary thyroid cancer in most cases and group 2 revealed follicular adenoma in most cases. Age over 40 years, ultrasonographic findings suggestive of malignancy, more than 2 results of atypia from repeated FNAs and nodules less than 2 centimeters were risk factors for malignancy on univariate analysis. Multivariate analysis showed that ultrasonographic findings suggestive of malignancy was a significant risk factor for malignancy. CONCLUSION: For proper evaluation of the risk for malignancy in thyroid AUS patients, the ultrasonographic criteria should be considered along with other clinicopathological findings such as age, nodule size, number of atypia, cytologic features.

Invasive Micropapillary Carcinoma of the Breast: MR Imaging Findings

OBJECTIVE: To analyze the magnetic resonance (MR) imaging findings of invasive micropapillary carcinoma of the breast. MATERIALS AND METHODS: MR images were retrospectively evaluated in 14 patients (age range: 37-67, mean age: 49 years) with pathologically confirmed invasive micropapillary carcinoma of the breast. The enhancement type (mass/non-mass), shape, margin, contrast enhancement, and time-intensity curve pattern on the dynamic study were correlated with the histopathologic features. Associated findings, such as edema, nipple change, skin change and enlarged axillary lymph nodes were also studied. RESULTS: The most common features of the masses were irregular shape (12 of 14 patients, 85.8%) and irregular or spiculated margin (11 of 14 patients, 78.7%). The contrast enhancement was heterogeneous in 11 patients (78.7%), rim enhancement in 2 cases (14.2%), and homogeneous in one patient (7.1%). The predominant kinetic pattern was rapid increase (14 of 14, 100%) in the initial phase and washout (11 of 14, 78.7%) in the delayed phase. Associated non-mass like enhancement was shown in 4 patients, representing ductal carcinoma in situ. MR imaging helped detect additional sites of cancer other than the index lesion in 3 patients (21.4%). Enlarged axillary lymphadenopathy was identified in 7 of the 14 patients (50%). CONCLUSION: Invasive micropapillary carcinoma appears as a mass with an irregular shape, irregular or spiculated margin and heterogeneous enhancement on MR imaging. Though these findings are not specific and are also observed with other breast malignancies, invasive micropapillary carcinoma frequently showed multiple lesions, accompanying non-mass enhancement and axillary lymph node enlargement.