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Biomedical subjects

Ki Keun Oh

Publications and source records attributed to Ki Keun Oh.

At least 19 recordsLinked to original sources

Columnar cell lesions of the breast: mammographic and US features.

OBJECTIVES: Columnar cell lesions are being encountered with increasing frequency in breast biopsies performed. The purpose of our study was to determine whether columnar cell lesions of the breast have any distinctive imaging characteristics. MATERIALS AND METHODS: We retrospectively reviewed our institutional database for all records of breast pathology obtained in a 17-month period. Columnar cell lesion was diagnosed in 53 lesions and 12 of these 53 lesions contained columnar cell lesions as the sole histopathologic findings. These 12 lesions in nine patients made up our study population. They included columnar cell change (n=4), columnar cell hyperplasia (n=5), and columnar cell hyperplasia with atypia (n=3). RESULTS: All nine patients underwent mammography and sonography within 1 month of each other. Of the mammograms in nine patients, nine lesions (75%) appeared as clustered amorphous or indistinct (n=5), fine pleomorphic (n=3), or round (n=1) microcalcifications. The tenth lesion showed a focal mass without microcalcifications and the remaining two lesions showed no abnormal findings. At sonography, not-circumscribed masses were depicted in six lesions and microcalcifications were visible in four lesions, of which three lesions were concurrent with masses. There were no sonographically focal lesions in the remaining five. Overall 11 lesions were classified as BI-RADS category 4 (92%) and one as category 3. Of the three lesions with atypia, two were classified as category 4a and one was classified as category 4c, and they showed no distinct imaging appearance from those without atypia. CONCLUSION: Columnar cell lesions usually present as nonpalpable, clustered indeterminate or suspicious microcalcifications on mammography. They are indistinguishable from other causes of suspicious microcalcifications such as atypical ductal hyperplasia or ductal carcinoma in situ and require needle biopsy or excisional biopsy for diagnosis.

Adult↗

Pregnancy-associated breast disease: radiologic features and diagnostic dilemmas.

In this paper, we evaluate the radiological features of pregnancy-associated breast lesions and discuss the difficulties in diagnosis by imaging. We selected patients who were diagnosed with pregnancy-associated breast lesions during the previous 5 years. All patients complained of palpable lesions in the breast and underwent ultrasonographic (US) examination, the first choice for examination of pregnancy-related breast lesions. Any suspicious lesions found by the US were recommended for a US-guided core biopsy, US-guided fine needle aspiration (FNA), or surgery. Various breast lesions were detected during pregnancy and lactation, including breast cancer, mastitis and abscesses, lactating adenoma, galactoceles, lobular hyperplasia, and fibroadenomas. The imaging features of pregnancy-associated breast lesions did not differ from the features of non-pregnancy-associated breast lesions; however, some pregnancy-associated benign lesions had suspicious sonographic features. A US-guided core biopsy was necessary for differentiating benign from malignant. In patients with breast cancer, the cancer was often advanced at the time of diagnosis. In conclusion, various pregnancy-related breast lesions were detected and the imaging of these lesions had variable findings. Breast ultrasound could be an excellent imaging modality for diagnosis and differentiation between benign and malignant lesions. However, when the imaging results are suspicious, a biopsy should be performed to obtain a pathologic diagnosis.

Adult↗

Radiologic and clinical features of idiopathic granulomatous lobular mastitis mimicking advanced breast cancer.

Idiopathic granulomatous lobular mastitis (IGLM), also known as idiopathic granulomatous mastitis, is a rare chronic inflammatory lesion of the breast that can clinically and radiographically mimic breast carcinoma. The aim of this study was to describe the radiological imaging and clinical features of IGLM in order to better differentiate this disorder from breast cancer. We performed a retrospective analysis of the clinical and radiographic features of 11 women with a total of 12 IGLM lesions. The ages of these women ranged between 29 and 42 years, with a mean age of 34.8 years. Ten patients were examined by both mammography and sonography and one by sonography alone. The sites that were the most frequently involved were the peripheral (6/12), diffuse, (3/12), and subareolar (3/12) regions of the breast. The patient mammograms showed irregular ill-defined masses (7/11), diffuse increased densities (3/11), and one oval obscured mass. In addition, patient sonograms showed irregular tubular lesions (7/12) or lobulated masses with minimal parenchymal distortion (2/12), parenchymal distortion without definite mass lesions (2/12), and one oval mass. Subcutaneous fat obliteration (12/12) and skin thickening (11/12) were also observed in these patients. Contrary to previous reports, skin changes and subareolar involvement were not rare occurrences in IGLM. In conclusion, the sonographic features of IGLM show irregular or tubular hypoechoic masses with minimal parenchymal distortion. Both clinical information and the description of radiographic features of IGLM may aid in the differentiation between IGLM and breast cancer, however histological confirmation is still required for the proper diagnosis and treatment of the disorder.

Adult↗

Sonographic screening for thyroid cancer in females undergoing breast sonography.

OBJECTIVE: The purpose of our prospective study was to evaluate incidental thyroid cancer diagnosed by screening sonography in a population who underwent breast sonography and the differences in the incidences of thyroid cancer between those with and those without breast cancer. SUBJECTS AND METHODS: Between January 2003 and March 2004, we examined thyroid glands during routine diagnostic or follow-up breast sonography. A total of 5,549 females underwent breast and thyroid screening sonography (n = 4,864) or sonography for diagnosis or follow-up of breast cancer (n = 685). When a thyroid lesion was suspicious for malignancy, sonographically guided fine-needle aspiration was performed. We compared the cases of pathologically proven thyroid cancer in two groups: a cancer group, including patients with breast cancer, and a noncancer group, including patients with negative or benign breast disease. RESULTS: Among the 5,549 cases, 42 (0.76%) were diagnosed as thyroid cancer; all were papillary carcinomas. Pathologically proven thyroid cancers were identified in 13 (1.9%) of the 685 breast cancer patients and in 29 (0.6%) of the 4,864 non-breast-cancer patients. The diameters of the 13 thyroid masses were 0.1-3.0 cm; the mean diameters in the cancer and noncancer groups were 9.9 and 8.6 mm, respectively. CONCLUSION: The incidence of thyroid cancer was significantly higher in the group with breast cancer than in the group who did not have breast cancer. The results of routine concurrent sonographic breast and thyroid examinations were helpful in detecting small thyroid tumors in both patient groups.

Adolescent↗

Application of the breast imaging reporting and data system final assessment system in sonography of palpable breast lesions and reconsideration of the modified triple test.

OBJECTIVE: The purpose of our study was to evaluate the utility of the American College of Radiology's Breast Imaging Reporting and Data System (BI-RADS) sonographic final assessment system and palpation-guided fine-needle aspiration (FNA) for evaluation of palpable breast lesions. METHODS: Our computerized database identified 160 palpable lesions of the breast in which follow-up palpation-guided FNA, targeted sonography, and pathologic confirmation were performed. We used BI-RADS sonographic data on all lesions. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of malignancy were calculated for sonography and palpation-guided FNA. Two-sample binomial proportion tests were used as the statistical analysis (P<.05). RESULTS: The FNA results were defined as benign, atypical cells, suspicious for malignancy, malignancy, and insufficiency. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 90.9%, 82.7%, 84.3%, 57.7%, and 97.2%, respectively, on sonography and 75.8% to 90.9%, 82.7% to 98.4%, 84.3% to 94.4%, 57.7% to 92.6%, and 93.9% to 97.2% on FNA. There was no statistically significant difference for sensitivity and negative predictive value between the two examinations. CONCLUSIONS: The diagnostic accuracy of sonography was similar to that of palpation-guided FNA for not missing the malignancy. Clinical application of FNA results can be difficult, especially when the result is insufficiency or atypical cells. Moreover, FNA is invasive and overlaps other procedures. Therefore, we conclude that sonography can replace palpation-guided FNA for diagnosis of palpable lesions of the breast when the BI-RADS sonographic final assessment system is used appropriately.

Adolescent↗

Galactoceles mimicking suspicious solid masses on sonography.

OBJECTIVE: The purpose of this study was to evaluate the sonographic appearance of a galactocele that can sonographically mimic a suspicious solid mass and to differentiate between a galactocele and a solid mass. METHODS: From September 2002 to February 2004, 33 galactoceles classified as Breast Imaging Reporting and Data System category 4 were included. They were all confirmed by sonographically guided core biopsies. Their sonographic imaging and clinical findings were reviewed retrospectively. RESULTS: The lesions had a round or irregular shape in 26 patients (78.8%), a noncircumscribed margin in 31 (93.9%), a nonparallel orientation in 22 (66%), and posterior shadowing in 13 (39.4%). Twenty-five nodules (75.8%) had internal hypoechogenicity or mixed echogenicity. Twenty-nine (87.9%) of 33 lesions showed a relatively sharp convex echogenic rim on the anterior or posterior wall. CONCLUSIONS: Galactoceles have various sonographic findings, many of which are similar to those of suspicious solid breast masses. However, there is a tendency for a galactocele to appear as a small, round hypoechoic nodule with an indistinct or microlobulated margin and mild posterior shadowing. It is helpful to search for a partial anterior or posterior echogenic rim to identify a galactocele.

Adult↗

Application of power Doppler vocal fremitus sonography in breast lesions.

OBJECTIVE: The purpose of this study was to illustrate the method and use of power Doppler vocal fremitus (PDVF) sonography in the detection and diagnosis of breast lesions. METHODS: One case was evaluated by various sonographic parameters and equipment to determine how the VF images were affected. Cases illustrative of a broad range of breast conditions were also collected. Each image pair consisted of B-mode and VF images to maintain an identical projection and to illustrate the influence of PDVF sonography. RESULTS: With B-mode and PDVF sonography, we evaluated and compared various breast conditions, including normal anatomic structures and abnormal lesions. We found that PDVF sonography is useful for distinguishing abnormal masses from normal tissue, such as differentiating between isoechoic tumors and isoechoic glandular tissues, and discriminating entrapped fat lobules from isoechoic tumors. Furthermore, PDVF sonography was useful for determining whether intracystic echoes are attached to the cyst wall. CONCLUSIONS: Power Doppler VF imaging is a valuable adjunct tool to B-mode sonography in the evaluation of breast lesions.

Adult↗

Unilateral breast edema: spectrum of etiologies and imaging appearances.

Breast edema is defined as a mammographic pattern of skin thickening, increased parenchymal density, and interstitial marking. It can be caused by benign or malignant diseases, as a result of a tumor in the dermal lymphatics of the breast, lymphatic congestion caused by breast, lymphatic drainage obstruction, or by congestive heart failure. Here we describe several conditions, that cause unilateral breast edema with the aim of familiarizing radiologists with these disease entities.

Breast Diseases↗

Malignant fibrous histiocytoma of chest wall.

Primary malignant fibrous histiocytoma (MFH) of the chest wall is rare. We report a case of primary MFH arising from the chest wall, which was thought to be a metastasis or myeloma. The imaging study revealed a single mass of the chest wall involving a rib. Resection and chest wall reconstruction was done. The histologic diagnosis was storiform-pleomorphic primary MFH. Although MFH of the chest wall is an uncommon pathology, it should be considered in the differentiation of a single bony destructive lesion involving the rib with a soft tissue component.

Adult↗

Focal fibrosis of the breast diagnosed by a sonographically guided core biopsy of nonpalpable lesions: imaging findings and clinical relevance.

OBJECTIVE: The purpose of this study was to evaluate the frequency of focal fibrosis of the breast diagnosed by a sonographically guided core biopsy of nonpalpable lesions, to characterize imaging features, and to evaluate their clinical relevance. METHODS: In a retrospective review of 724 lesions that underwent sonographically guided core biopsy of nonpalpable breast lesions, 62 cases had a diagnosis of focal fibrosis. Two radiologists analyzed the sonographic and mammographic findings according to the Breast Imaging Reporting and Data System. The results were compared with histologic findings at surgery or imaging findings during surveillance. RESULTS: The incidence of focal fibrosis was 8.6% (62/724). Sonographic films were available in 56 cases, so 56 cases were reviewed for their sonographic findings. Among the mammograms reviewed, 64.7% (33/51) had negative findings. Among the sonograms reviewed, the most common features were oval shape (32/56, 57.1%), parallel orientation (36/56, 64.3%), microlobulated margin (24/56, 42.9%), abrupt interface (50/56, 89.3%), isoechoic pattern (42/56, 75.0%), and a lack of posterior acoustic features (45/56, 80.4%). The Breast Imaging Reporting and Data System final assessment was category 3 in 27 (48.2%) and category 4 in 29 (51.8%). Most of the category 4 lesions were category 4A (26/29, 89.7%). Surgical excision (n = 7) and follow-up for at least 1 year (n = 49) showed no malignancy. CONCLUSIONS: Focal fibrosis was found in 8.6% by a sonographically guided core biopsy of nonpalpable breast lesions. Most of the lesions were categorized as probably benign (category 3) or having a low suggestion of malignancy (category 4A). Focal fibrosis diagnosed at core biopsy can be managed with a 6-month follow-up protocol.

Adult↗

Characteristic imaging features of breast fibroadenomas in women given cyclosporin A after renal transplantation.

PURPOSE: This retrospective study was conducted to determine the characteristic imaging and histopathologic features of breast fibroadenomas in kidney-transplant recipients given chronic cyclosporin A immunosuppressive therapy after the transplantation and to compare these characteristics with those from a control group. METHODS: From January 1, 1990, through December 31, 1999, 486 women underwent renal transplantation at our institution. All patients subsequently received immunosuppressive therapy with cyclosporin A and prednisolone. Ten (2%) of these women had developed breast fibroadenomas during this chemotherapy. We compared the data obtained on this group's fibroadenomas with those obtained from those in the control group, which comprised 100 women with fibroadenomas but who had never undergone organ transplantation or immunosuppressive therapy. RESULTS: Twenty-two fibroadenomas developed in the 10 transplant recipients. Eight of those 10 had multiple lesions, and 7 were affected bilaterally. The mean diameter of the fibroadenomas was 4.2 +/- 2.5 cm. Mammographically, the lesions were round or oval high-density masses with well-circumscribed margins and no calcification or spiculation. Sonographically, the lesions were relatively highly echogenic and had a lower ratio of the longitudinal to the anteroposterior diameter (L /AP) than did those in the control group. Histopathologically, the features of these lesions were generally typical of fibroadenomas, but some were more typical of malignant lesions. Among the 100 control patients, 146 fibroadenomas developed; 33 women had multiple lesions, and 12 were affected bilaterally. Their fibroadenomas had a mean diameter of 2.1 +/- 1.5 cm, and the imaging features of these lesions were typical of fibroadenomas. CONCLUSIONS: The fibroadenomas that developed in kidney-transplant recipients given chronic cyclosporin A and prednisolone immunosuppressive therapy had a tendency to be multiple, bilateral, and larger than those that developed in the control patients. These fibroadenomas also exhibited some imaging features that differed from those of typical fibroadenomas that develop in women who have not undergone organ transplantation or immunosuppressive therapy.

Adolescent↗

Microwave detection of metastasized breast cancer cells in the lymph node; potential application for sentinel lymphadenectomy.

Metastasis is the leading cause of death in breast cancer patients and an appropriate detection of metastasis can provide better prognosis and quality treatments. Microwaves can reveal the unique electromagnetic properties of materials, and this study aims to unleash the electromagnetic properties of breast cancer cells, especially, metastasized cancer cells in the lymph nodes, using broad-band microwaves in attempts to detect metastases. To distinguish the cancer-specific patterns of cancer tissues, three primary microwave parameters were assessed, i.e., permittivity in mid-band frequency (3-5 GHz), conductivity in high-band frequencies (25-30 GHz) and slope changes of permittivity at high-band frequencies (15-30 GHz). An additional parameter, Cancer Metastasis Index (CMI), was developed to effectively represent all parameters. Broadband microwave scanning can reveal cancer specific electromagnetic behaviors in all three parameters, and these were reliably reflected by CMI. CMI effectively magnified the difference of the electromagnetic properties between normal nodal tissues and cancer tissues. immunohistochemistries were performed to verify the origin of electromagnetic changes represented by CMI values.

Breast Neoplasms↗

Variable breast conditions: comparison of conventional and real-time compound ultrasonography.

OBJECTIVES: To illustrate and compare the appearances of variable breast conditions by conventional and real-time spatial compound images. METHODS: Cases illustrative of a broad range of breast conditions were collected. Each image pair consisted of conventional and real-time compound images with a stationary probe to maintain an identical projection. RESULTS: The various breast conditions, including normal anatomic structures and abnormal lesions, were evaluated and compared by conventional and real-time compound images. The real-time compound images revealed more realistic and clear images with reduced artifacts. CONCLUSIONS: Real-time compound images are superior to conventional images of normal and abnormal breast conditions. Real-time compound imaging is a good technique for evaluating the breast state.

Adult↗