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Hak Hee Kim

Publications and source records attributed to Hak Hee Kim.

13 recordsLinked to original sources
PubMed2006

Clinicopathologic significance of the basal-like subtype of breast cancer: a comparison with hormone receptor and Her2/neu-overexpressing phenotypes.

DNA microarray profiling studies have led to the classification of invasive breast carcinoma into luminal/estrogen receptor-positive, normal breast-like, Her2/neu-overexpressing, and basal-like types. Among these groups, the basal-like subtype is associated with the poorest clinical outcome in Western countries. To date, the clinicopathologic characteristics of the basal-like carcinomas, compared with other subtypes, have not been described in the Korean population. In this study, we used tissue microarray to examine the expression of basal cytokeratins (CK) (CK5 and CK14) and luminal CK (CK8/18), epidermal growth factor receptor, c-kit, hormone receptors (HRs), p53, and Her2/neu in 776 consecutive patients diagnosed with invasive breast carcinoma from January 1993 to December 1998 and categorized these cases into 5 subgroups (basal-like, HR-expressing, Her2/neu-overexpressing, HR and Her2/neu-expressing, and null subtypes negative for all markers), based on the immunohistochemical data. We identified cases of 114 (14.7%) basal-like, 345 (44.5%) HR-expressing, 133 (17.1%) Her2/neu-overexpressing, 61 (7.8%) HR and Her2/neu-expressing, and 123 (15.9%) null subtypes. Histologically, most basal-like breast cancers were invasive ductal carcinoma, not otherwise specified (98 cases, 86.0%), with high nuclear and/or histologic grades, and most metaplastic carcinomas (6 [75.0%] of 8 cases) were the basal-like subtype. Both basal-like and Her2/neu-overexpressing subtypes were associated with larger tumor sizes (mean, 3.6 and 3.3 cm, respectively) than the HR-expressing group (mean, 2.8 cm) (P = .001 and P = .036, respectively). Nodal stage of Her2/neu-overexpressing subtype was higher than that of basal-like subtype; however, overall stage was not different between the 2 groups (P = .010 and .123, respectively). Distant metastasis was most frequently observed in the Her2/neu-overexpressing subtype (33.8%), which was prognostically the worst subgroup of breast cancers. In contrast to previous findings from Western countries, our analyses reveal that the Her2/neu status is the most important prognostic factor of breast cancers.

Adult↗
PubMed2006

The sternalis muscles: incidence and imaging findings on MDCT.

OBJECTIVE: We studied the incidence and appearance of the sternalis muscles on multidetector computed tomography (MDCT) to permit the differentiation of the sternalis from significant pathologic condition. METHODS: We retrospectively evaluated consecutive contrast-enhanced 16 row MDCT scans of the chest obtained in 1387 Korean patients (790 males and 597 females) between September 2003 and January 2005. All computed tomography scans were obtained in the supine position. Age ranges were 16 to 87 years and average was 59.2 years. Imaging analysis was based upon distribution (unilateral or bilateral, size, shape, and location). Statistical differences were evaluated by chi tests and Independent Samples t tests. RESULTS: The sternalis muscle was present in 86 (6.2%) of 1387 patients. This muscle was more common in female (44 of 597, 7.3%) than in male (42 of 790, 5.3%) patients, but statistical significance was not noted (P=0.058). Twenty-three patients showed bilateral sternalis muscles. Among 63 patients with unilateral sternalis muscles, 28 patients showed left sternalis muscles and 35 patients showed right sternalis muscles. Unilateral distribution was more common. The height, AP diameter, and width of the sternalis muscle were not significantly different between unilateral and bilateral muscles (P=0.182, 0.911, and 0.114, respectively). The height and AP diameter showed no significant difference between male and female (P=0.470, 0.329, respectively) patients, but the width was wider in male (P<0.001) patients. All sternalis muscles showed flat appearance, except for 1 case. The sternalis muscles were located longitudinally in parasternal position in all cases. CONCLUSIONS: The sternalis muscle is an unusual normal variant of the chest wall musculature running parallel to the sternum with various sizes and most sternalis muscles are flat on MDCT. Unilateral distribution is more common, and the size of muscle is larger in males. Its incidence is 6.2% in Korean population. Radiologists should be familiar with the image findings of the sternalis muscle to avoid any confusing pathologic lesions and facilitate its clinical use such as flap.

Adult↗
PubMed2006

Comparison of calcification specificity in digital mammography using soft-copy display versus screen-film mammography.

OBJECTIVE: The purpose of this study was to compare specificity in the interpretation of calcifications in soft-copy reviewing of digital mammograms versus hard-copy reviewing of screen-film mammograms. MATERIALS AND METHODS: A total of 130 consecutive cases with calcifications (44 malignant and 86 benign) that had been evaluated with needle or surgical biopsy were collected. Both screen-film mammography and soft-copy digital mammography were obtained in the same patients under existing research protocols using Fischer Imaging's SenoScan (n = 71), Lorad's digital mammography system (n = 35), and GE Healthcare's Senographe 2000D (n = 24). Eight trained radiologists scored all lesions--cropped or masked to display just the region of interest--both on screen-film and soft-copy digital mammography with a month between reviews to reduce the effects of learning and memory. A 5-point malignancy scale was used, with 1 as definitely not, 2 as probably not, 3 as possibly, 4 as probably, and 5 as definitely. Reviewers were randomly assigned condition order, and images within each condition were randomly ordered. Repeated measures analysis of variance was used to test for differences between conditions in specificity computed via nonparametric receiver operating characteristic (ROC) study separately for each reviewer and condition. RESULTS: Across all reviewers, the mean specificity for 1 or 2 versus 3, 4, or 5 was 0.803 for screen-film mammography (range, 0.413-0.938; SD +/- 0.166) and 0.833 for soft-copy image (range, 0.375-0.951; SD +/- 0.187). Although not statistically significant (Student's t test p values from 0.19 to 0.99 across all cut points), numeric values of specificity were consistently higher for soft-copy versus screen-film mammography. No statistical significance in specificity was seen using all possible cut points in the 5-point scale, although the primary analysis used the cutpoint for differentiation between benign and malignant cases as 1 or 2 versus 3, 4, or 5. CONCLUSION: No statistically significant difference was shown in specificity achievable using soft-copy digital versus screen-film mammography in this study.

Biopsy↗
PubMed2005

Protection of osteoblastic cells from freeze/thaw cycle-induced oxidative stress by green tea polyphenol.

Green tea polyphenol (GTP) together with dimethylsulphoxide (DMSO) were added to a freezing solution of osteoblastic cells (rat calvarial osteoblasts and human osteosarcoma cells) exposed to repeated freeze/thaw cycles (FTC) to induce oxidative stress. When cells were subjected to 3 FTCs, freezing medium containing 10% (v/v) DMSO and 500 mug GTP ml(-1) significantly (p<0.05) suppressed cell detachment and growth inhibition by over 63% and protected cell morphology. Furthermore, the alkaline phosphatase activity of osteoblastic cells was appreciably maintained after 2 and 3 FTCs in this mixture. Polyphenols may thus be of use as a cell cryopreservant and be advantageous in such fields as cell transplantation and tissue engineering.

Alkaline Phosphatase↗
PubMed2005

Spectrum of sonographic findings in superficial breast masses.

OBJECTIVE: The purpose of this presentation is to show the sonographic findings of breast masses, which can occur in subcutaneous fat or in the cutaneous layer of the breast. METHODS: We reviewed the sonographic findings of superficial breast masses, including the epidermal inclusion cyst, steatocystoma multiplex, fat necrosis, accessory breast, Mondor disease, sparganosis, neurofibroma, tuberculosis, mastitis, and breast malignancy. RESULTS: Specific sonographic features of superficial breast masses have been illustrated. CONCLUSIONS: Radiologists must be familiar with the sonographic findings of various diseases involving the superficial layer of the breast to avoid further patient workup.

Breast Diseases↗
PubMed2004

Diagnostic accuracy of Fischer Senoscan Digital Mammography versus screen-film mammography in a diagnostic mammography population.

RATIONALE AND OBJECTIVES: To compare the diagnostic accuracy of the Fischer Senoscan Digital Mammography System with that of standard screen-film mammography in a population of women presenting for screening or diagnostic mammography. MATERIALS AND METHODS: Enrollment of patients took place at six different breast-imaging centers between 1997 and 1999. A total of 247 cases were selected for inclusion in the final reader study. All known cancer cases were included (111) from all six participating sites representing 45% of the total cases. The remaining 136 cases (55%) were randomly selected from all available benign or negative cases from three of the six sites. A complete case consisted of both a (unilateral or bilateral) digital and screen-film mammogram of the same patient. Eight radiologists interpreted the cases in laser-printed digital and screen-film hardcopy formats. The study was designed to detect differences of 0.05 in the ROC area under the curve (AUC) between digital and screen-film radiologist interpretation performance. RESULTS: The average AUC for the Senoscan digital was 0.715 for the 8 readers. The average AUC for screen-film was 0.765. The difference AUC of -0.05 falls within the 95% confidence interval (-0.101, 0.002). The average sensitivity was 66% and specificity 67% for SenoScan full-field digital mammography. The average screen-film mammography sensitivity and specificity were 74% and 60%, respectively. CONCLUSION: No statistically significant difference in diagnostic accuracy between the Fischer Senoscan and screen-film mammography was detected in this study.

Adult↗
PubMed2003

Pregnancy- and lactation-associated breast cancer: mammographic and sonographic findings.

OBJECTIVE: To evaluate the mammographic and sonographic findings of pregnancy-associated breast cancer. METHODS: A total of 22 consecutive patients with breast cancer pathologically diagnosed during pregnancy (n = 10) or lactation (n = 12) were included in this study. The ages of the patients ranged from 26 to 49 years. Both mammography and sonography were performed on 12 patients; sonography only was performed on 7 patients; and mammography only was performed on 3 patients. Mammographic and sonographic findings were evaluated retrospectively. RESULTS: Mammography revealed positive findings in 13 (86.7%) of 15 patients, even though all 15 patients had dense breasts. Mammographic findings included masses (n = 5), masses with calcifications (n = 2), calcifications with axillary lymphadenopathy (n = 2), a mass with axillary lymphadenopathy (n = 1), calcifications alone (n = 1), asymmetric density alone (n = 1), and diffuse skin and trabecular thickening alone (n = 1). Sonographic findings were positive and showed masses for all 19 patients (100%). The common sonographic findings of masses were irregular shapes (n = 15), irregular margins (n = 16), parallel orientation (n = 11), complex echo patterns (n = 14, including marked cystic [anechoic] components [n = 4]), and posterior acoustic enhancement (n = 12). Surrounding tissue effects could be seen in 5 patients, including ductal changes (n = 2), Cooper ligament thickening (n = 1), edema (n = 3), and skin thickening (n = 3). Calcifications within or outside a mass (n = 7) and axillary lymphadenopathy (n = 8) were also detected. CONCLUSIONS: Although a mass could not be discernible by mammography because of increased radiodensity during pregnancy or lactation, calcification, asymmetric density, axillary lymphadenopathy, and skin and trabecular thickening were helpful for diagnosis of pregnancy-associated breast cancer. Sonographic findings of a solid mass with posterior acoustic enhancement and a marked cystic component were somewhat different from the appearance of breast cancer in nonpregnant women, possibly because of the physiologic changes of pregnancy and lactation.

Adult↗
PubMed2002

New subtraction algorithms for evaluation of lesions on dynamic contrast-enhanced MR mammography.

We report new subtraction algorithms for the detection of lesions in dynamic contrast-enhanced MR mammography(CE MRM). Twenty-five patients with suspicious breast lesions underwent dynamic CE MRM using 3D fast low-angle shot. After the acquisition of the T1-weighted scout images, dynamic images were acquired six times after the bolus injection of contrast media. Serial subtractions, step-by-step subtractions, and reverse subtractions, were performed. Two radiologists attempted to differentiate benign from malignant lesion in consensus. The sensitivity, specificity, and accuracy of the method leading to the differentiation of malignant tumor from benign lesions were 85.7, 100, and 96%, respectively. Subtraction images allowed for better visualization of the enhancement as well as its temporal pattern than visual inspection of dynamic images alone. Our findings suggest that the new subtraction algorithm is adequate for screening malignant breast lesions and can potentially replace the time-intensity profile analysis on user-selected regions of interest.

Adult↗
PubMed2002

Independent component analysis for the examination of dynamic contrast-enhanced breast magnetic resonance imaging data: preliminary study.

RATIONALE AND OBJECTIVE: An application of independent component analysis (ICA) is reported for the detection and characterization of breast lesions in dynamic contrast-enhanced MRI. The ICA technique, which uses a novel statistical algorithm to separate mixed signal sources of unknown nature, enables the extraction of spatial and temporal features of dynamic MRI data. MATERIALS AND METHODS: Six patients with confirmed lesion diagnosis (three with malignancy and three with benign condition) participated in this study. T1-weighted MRI covering both breast volumes was dynamically acquired in every 90 seconds after the bolus injection of contrast media using three-dimensional fast low-angle shot sequence (3-D FLASH). RESULTS: With the application of the ICA, differential signal responses were delineated from benign and malignant lesions, and areas with high temporal correlations with the extracted signal components were selectively visualized. CONCLUSIONS: The results suggest that ICA allowed for an identification of lesion morphology and lesion-specific dynamic enhancement patterns.

Adult↗
PubMedDate not supplied

Thoracic manifestations of breast cancer and its therapy.

Breast cancer is the second most common cause of cancer-related death in women. In most patients, imaging demonstrates thoracic changes resulting from either treatment, complications of treatment, or tumor recurrence or metastasis. The postsurgical imaging appearance of the chest wall depends on the surgical method used (radical mastectomy, modified radical mastectomy, breast-conserving surgery, breast reconstruction). The most common surgery-related complication is seroma. Radiation therapy frequently causes radiation pneumonitis, which occurs approximately 4-12 weeks after the completion of therapy and is characteristically limited to the field of irradiation. Chemotherapy-related complications include cardiotoxicity, pneumonitis, and infection. Ultrasonography and computed tomography are more sensitive than physical examination for detecting local and regional recurrence. The thorax is a common site of metastasis, which may affect the lymph nodes, bone, lung, pleura, or heart and pericardium. Bone metastasis is usually evaluated with bone scintigraphy and may cause spinal cord compression, a serious complication that requires early diagnosis. Intrapulmonary metastasis may manifest as single or multiple pulmonary nodules, airspace pattern metastasis, lymphangitic metastasis, or endobronchial metastasis. Pleural metastasis usually manifests as pleural effusion, with or without a pleural mass. Familiarity with the spectrum of radiologic findings in breast cancer patients allows accurate image interpretation and correct diagnosis.

Adult↗
PubMedDate not supplied

Prenatal sonographic and MR imaging findings of extensive fetal lymphangioma: a case report.

We report the imaging findings in a case of fetal lymphangioma involving the retroperitoneum and right lower extremity, and diagnosed by ultrasonography and magnetic resonance (MR) imaging at 26 weeks of gestation. Prenatal ultrasonograms and T2-weighted single-shot fast spin-echo MR images clearly revealed an extensive, multilocular cystic mass with internal hemorrhage in the retroperitoneum extending to the lower extremity.

Abortion, Eugenic↗