Trends in contralateral prophylactic mastectomy rate according to clinicopathologic and socioeconomic status

PURPOSE: There has been an increasing trend in the use of contralateral prophylactic mastectomy (CPM) among women diagnosed with unilateral breast cancer or mutations in BRCA1 or BRCA2 to reduce the occurrence of contralateral breast cancer. This study aimed to examine trends in the CPM rate according to clinicopathologic and socioeconomic status at a single institution in Korea. METHODS: This study included 128 patients with mutations in BRCA1 or BRCA2. Patients were divided into a CPM group (n = 8) and a non-CPM group (n = 120) between May 2013 and March 2016. The main outcome variables, including epidemiology, clinical features, socioeconomic status, and tumor characteristics, were analyzed. RESULTS: A total of 8 CPMs were performed among 128 patients. All CPM patients were married. The proportion of professional working women was higher in the CPM group (P = 0.049). Most patients who underwent CPM graduated college, compared to less than a third of the non-CPM group (P = 0.013). The CPM group had a higher rate of visits to the Hereditary Breast and Ovarian Cancer (HBOC) clinic (P = 0.021). The risk-reducing salpingo-oophorectomy (RRSO) rate was significantly higher in the CPM group (P < 0.01). CONCLUSION: CPM rates were significantly different according to socioeconomic status. The CPM rate tends to increase in highly educated and professional working women. The socioeconomic status of patients is an important factor in the decision to participate in the HBOC clinic and undergo CPM or RRSO.

Frequency of Mutation of Codon 249, Overexpression of p53, and Hepatitis B Virus DNA Positivity in Hepatocellular Carcinoma / 대한임상미생물학회지

BACKGROUND: In hepatocellular carcinoma (HCC), the frequency of p53 mutation and the association with hepatitis B virus (HBV) infection varies with geographic locations and risk factors. The aim of this study was to determine the frequency of codon 249 mutation of p53, p53 overexpression, and HBV DNA positivity and to observe the relationship between them in Korean HCC. METHODS: We analyzed overexpression of p53 in hepatoma tissue from 17 HCC patients by immunohistochemistry (IHC), specific mutations at the third base position of codon 249 by PCR-restriction fragment length polymorphism (PCR-RFLP) method, and presence of HBV by nested PCR. RESULTS: Although a point mutation at codon 250 was seen in one (5.8%) of 17 patients, no codon 249 mutations were found in the patient cohort. The p53 protein was overexpressed in 4 (23.5%) of 17 HCCs. PCR for HBV DNA from HCCs showed a positivity rate of 82.4% (14 of 17 specimens). CONCLUSION: In HCC of this study, HBV infection was not associated with either 249 mutation or overexpression of p53, and overexpression of p53 protein seemed to be related to other than this mutation.

Effect on Cell Growth, c-myc mRNA Expression and Telomerase Activity by Transforming Growth Factor-beta1 in Malignant Lymphoma and Leukemia Cell Line

BACKGROUND: Transforming growth factor-beta1 (TGF-beta1) is known to be a potent growth inhibitor of many cell types, including most epithelial cells. However, the mechanism of TGF-beta1 action on cell growth in lymphomas and leukemia still remains to be elucidated. c-myc is a central regulator of cell proliferation and apoptosis, and telomerase is believed to play an important role in carcinogenesis. The aim of the study was to determine the effects of cell growth, c-myc gene expression and telomerase activity due to TGF-beta1 and examine its mechanism of action in lymphomas and leukemia. METHODS: The cell growths of Jiyoye (Burkitt lymphoma), H9 (T cell lymphoma), and CCRF-CEM (acute lymphocytic leukemia, T cell) cell lines due to TGF-beta1 were measured using the MTT assay. RT-PCR was also performed to monitor the expression of the c-myc gene in these cells with the telomerase activity measured using a TRAP assay. RESULTS: There was significant inhibition of cell growth in TGF-beta1 (5ng/mL) treated Jiyoye cells. When treated with TGF-beta1, the Jiyoye cells exhibited marked decreases in the levels of c-myc RNA and telomerase activity. However, TGF-beta1 treated H9 and CCRF-CEM cells showed no cell growth inhibition or reductions in the levels of c-myc mRNA and telomerase activity. The effect of TGF-beta1 on cell growth was noted to closely correlate with c-myc mRNA expression and telomerase activity. CONCLUSION: These results suggest that TGF-beta1 may inhibit cell growth in Jiyoye cells by a mechanism involving down-regulation of the c-myc gene, which in turn, reduces the telomerase activity.

Expression of Osteopontin, ZO-1 and E-cadherin in Adenoma and Adenocarcinoma of the Colon

Background : The expressions of osteopontin (OPN), zonula occludens-1 (ZO-1) and E-cadherin, known as cell adhesion-associated substances, were examined in adenoma and adenocarcinoma of the colon. The relationship of their expressions with clinicopathologic factors was examined to investigate the roles of these proteins in the development, invasion or metas- tasis of colon adenocarcinoma. Methods : The expressions of OPN, ZO-1, and E-cadherin were examined in 54 cases of adenoma and 67 cases of adenocarcinoma of the colon by immunohistochemical staining. Results : The expression of OPN in colon adenocarcinoma correlated with staging (p=0.012) and distant metastasis (p=0.021). The expression of ZO-1 was closely related with tumor cell differentiation (p<0.001), and the reduced expression of E-cadherin was associated with tumor cell differentiation (p=0.05) and lymph node metastasis (p<0.001). Co-expression of ZO-1 and E-cadherin was significantly associated with tumor cell differentiation, and the expressions of ZO-1 and E-cadherin were reduced or lost in all cases (5 cases) of poorly differentiated adenocarcinoma. Conclusions : Our data suggest that OPN is involved in the process of invasion and metastasis of colon adenocarcinoma, and ZO-1- and E-cadherin-mediated cell adhesion may play an important role in the differentiation of colon adenocarcinoma.

Significance of p53, cyclin D1 and c-myc Expressions in Thyroid Tumors

BACKGROUND: The G1/S phase proteins of the cell cycle play critical roles in tumorigenesis and tumor progression. Our aim was to investigate the significance of p53, cyclin D1 and c-myc expressions in thyroid tumors. METHODS: The expressions of these proteins were examined in 217 cases of thyroid tumors and tissues using immunohistochemistry. The results were correlated with lymph node metastasis. RESULTS: p53 expression was seen in 75.5, 47.5, 66.7, and 50% of papillary carcinomas (PC), follicular carcinomas (FC), undifferentiated carcinomas (UC) and follicular adenomas (FA), respectively. There was a significant difference between these expressions in these tumors and the results in nodular hyperplasia (NH) and normal tissues. Cyclin D1 expression was noted in 80.0, 68.4, 66.7, 61.1 and 79.5% of PC, FC, UC, FA and NH, respectively. c-myc expression was seen in 80.0, 94.2, 66.7, 66.7 and 52.3% of PC, FC, UC, FA and NH, respectively. There was a significant association between the expressions in these tumors and the results in normal tissues. The expressions of p53, cyclin D1 and c-myc were not correlated with lymph node metastasis. CONCLUSIONS: These findings suggest the expressions of p53, cyclin D1 and c-myc may act in the early stage, and participates in tumorigenesis and promoting cell growth.

Expression of the PTEN Gene Product in the Invasive Cancer of Breast and Its Relationship with Other Prognostic Factors

PURPOSE: The tumor suppressor gene PTEN is located on chromosome 10q23 and is mutated in a variety of sporadic cancers. The aim of this study is to understand the expression of the PTEN gene product in invasive breast cancer and its relationships with clinicopathologic factors of breast cancer. METHODS: The hospital records and pathologic findings of 57 patients who underwent breast operation due to invasive breast carcinoma between January 1996 and June 2002 were reviewed. We examined the relationships between PTEN expression and various clinicopathologic factors of breast cancer such as age, tumor size, lymph node metastasis, histologic grade, nuclear grade, stage and estrogen, and progesterone receptors. RESULTS: Among the 57 invasive breast cancers, 5 (8.8%) were immunohistochemically negative, and 14 (24.6%) had reduced expression of PTEN. Among clinicopathologic factors, age, tumor size, lymph node metastasis, stage, histologic grade, and estrogen receptor had no correlation with PTEN expression. Nuclear grade and positive progesterone receptor were significant correlated with decreased PTEN expression. However, these results are different from those of other reports showing that negative progesterone receptor was significantly correlated with the decrease of PTEN expression. CONCLUSION: According to other reports, PTEN expression does play some role as a prognostic factor for breast cancer, but the results of our study did not support this hypothesis. Further evaluation and study are required into the role of PTEN as a prognostic factor of breast cancer.

Expression of the PTEN Gene Product in the Invasive Cancer of Breast and Its Relationship with Other Prognostic Factors

PURPOSE: The tumor suppressor gene PTEN is located on chromosome 10q23 and is mutated in a variety of sporadic cancers. The aim of this study is to understand the expression of the PTEN gene product in invasive breast cancer and its relationships with clinicopathologic factors of breast cancer. METHODS: The hospital records and pathologic findings of 57 patients who underwent breast operation due to invasive breast carcinoma between January 1996 and June 2002 were reviewed. We examined the relationships between PTEN expression and various clinicopathologic factors of breast cancer such as age, tumor size, lymph node metastasis, histologic grade, nuclear grade, stage and estrogen, and progesterone receptors. RESULTS: Among the 57 invasive breast cancers, 5 (8.8%) were immunohistochemically negative, and 14 (24.6%) had reduced expression of PTEN. Among clinicopathologic factors, age, tumor size, lymph node metastasis, stage, histologic grade, and estrogen receptor had no correlation with PTEN expression. Nuclear grade and positive progesterone receptor were significant correlated with decreased PTEN expression. However, these results are different from those of other reports showing that negative progesterone receptor was significantly correlated with the decrease of PTEN expression. CONCLUSION: According to other reports, PTEN expression does play some role as a prognostic factor for breast cancer, but the results of our study did not support this hypothesis. Further evaluation and study are required into the role of PTEN as a prognostic factor of breast cancer.

Evaluation of Her-2/neu in Breast Cancer: Comparison of Immunohistochemistry and Polymerase Chain Reaction / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: In breast cancer, Her-2/neu amplification/overexpression predicts a poor clinical outcome, and enhanced survival benefits have been reported with Her-2/neu targeted therapy. Currently, there are several methods for assessing the amplification/overexpression of Her-2/neu, each having advantages and disadvantages. The aim of this work was to establish a reproducible, sensitive and specific method of testing for Her-2/neu, which could be used in diagnostic pathology laboratories. MATERIALS AND METHODS: We compared the immunohistochemistry (IHC) detection of Her-2/neu overexpression, with differential polymerase chain reaction (PCR) to assess the gene amplification of the Her-2/ neu, in 163 cases of invasive ductal carcinoma of the breast using paraffin-embedded tissue. In addition, assessment of the appropriate cut off points was established. RESULTS: The overexpression of the Her-2/neu was detected in 39 (23.9%) cases, and its amplification in 37 (22.7%) cases. The methods were positive in 21.5% of cases and negative in 74.8%. There was a 96.3% concordance between the two methods. The sensitivity and specificity of IHC, compared with PCR, were 94.6 and 96.8%, respectively. CONCLUSION: We conclude that the automation of PCR-based Her-2/neu testing approaches is expected to play an increasing role in the future of Her-2/neu testing. Also, we have demonstrated that IHC is a sensitive and specific method for assessing Her-2/neu stati in breast cancer, compared to PCR. The current study indicates that moderate, or strong, complete membrane staining in> or =10% of tumor cells provides an appropriate cut off point compared with PCR.

Studies of CD44s and CD44v6 Expressions and Correlation with Clinicopathologic Parameters in Gastric Carcinoma

BACKGROUND: The aim of this study is to elucidate the relationship between the CD44s and CD44v6 expression level and the biological characteristics of a gastric carcinoma. METHODS: CD44s and CD44v6 expression was investigated in 56 gastric carcinomas, 18 dysplasias, and 22 normal mucosae by immunohischemical staining. RESULTS: The CD44s and CD44v6 expression rates in gastric carcinomas, dysplasia, and normal mucosae were 80.3% and 83.9%, 72.2% and 77.8%, and 13.6% and 4.5%, respectively. Statistical analysis showed significant difference after comparing a gastric carcinomas and dysplasia to the normal mucosae (p<0.001). The CD44s and CD44v6 expression rates in the cases with invasion to the muscle proper and serosa were 60.7% and 57.1%, and 82.4% and 88.2%, respectively. Both showed a significant statistical difference compared to the expression rates in the cases with invasion to the mucosae and submucosae. The CD44s and CD44v6 expression rates in gastric carcinomas with a lymph node metastasis showed a statistically significant difference compared to those without a lymph node metastasis (p<0.001 and p<0.01, respectively). CD44s and CD44v6 were also expressed in the normal basal cells around gastric carcinomas. CONCLUSIONS: The CD44s and CD44v6 expression showed a significant relationship with gastric carcinogenesis, toward an aggressive biologic behavior.

Mantle Cell Lymphoma, Blastoid Variant, Diagnosed on the Basis of Cytomorphology and Flow Cytometric Immunophenotyping of the Lymph Node Aspirate and Peripheral Blood

Mantle cell lymphoma, blastoid variant (B-MCL), is a very rare type of non-Hodgkin 's lymphoma exhibiting an aggressive clinical course. We describe a case of B-MCL showing generalized lymphadenopathy and leukemic conversion in a 62-yr-old man. The case was diagnosed and subclassified as B-MCL on the basis of cyto-morphology and immunophenotype. Microscopic examination of the peripheral blood (PB) showed a spectrum of cells ranging from small mature lymphocytes to medium- and large-sized lymphocytes with blast-like chromatin and prominent nucleoli. The lymphoma cells were monoclonal B cells with moderately intense surface IgM. They were CD5 positive, cyclin D1 positive, CD10 negative, and CD23 negative. The flow cytometric immunophenotyping and DNA ploidy analysis of the PB and material obtained by aspiration cytology supported the diagnosis of B-MCL. These findings underline the utility of aspiration cytology in diagnosing B-MCL when cytomorphologic examination is combined with flow cytometric analysis of immuno-phenotype and demonstration of proliferation markers.

Lymphopenia after Mediastinal Irradiation in Lung Cancer / 대한방사선종양학회지

PURPOSE: This study was undertaken to retrospectively evaluate white blood cell kinetics, especially lymphocyte depression after different treatments, and to find the correlation between immunosuppression and large blood volume and dynamic blood flow within the mediastinal radiotherapy (RT) field in lung cancer. MATERIALS AND METHODS: Thirty-four patients with lung cancer were retrospectively evaluated; 10 patients had only radiotherapy (RT group), 8 had chemotherapy (CT group) and 16 had chemotherapy and radiotherapy (RT/CT group). The mean follow-up periods of the RT-including groups (RT group and RT/CT group) and the RT-excluding group (CT group) were 6 and 8 months, respectively. Complete blood cell counts including lymphocyte percentage (%) were checked weekly during RT but less frequently during CT and after RT. RESULTS: Changes in total white blood cell counts were not significantly different among the three groups. The lymphocyte count and lymphocyte % were much lower in the RT-including groups than in the RT- excluding group. The difference between pre-treatment and final lymphocyte count and the difference between pre-treatment and final lymphocyte % were significant (p=0.044 and p=0.037) between the RT- including groups and the RT-excluding group. CONCLUSION: Lymphopenia was more marked after treatment containing RT than CT only. Lymphopenia may be one cause of a compromised immune system after mediastinal irradiation in lung cancer. We suggest cautiously that previous studies showing evidence of lymphocyte apoptosis after low-dose irradiation and large blood volume and dynamic blood flow within the RT fields could be somewhat related to lymphopenia after mediastinal irradiation.

Apoptosis and Proliferative Activity of Non-Hodgkin's Lymphoma: Correlation with Bcl-2 and P53 Protein Expression / 대한방사선종양학회지

PURPOSE: Tumor growth in a given neoplasm is the net result of cell proliferation and cell loss, and apoptosis is the most significant component of continuous cell loss in most tumors. In this study, we examined non-Hodgkin's lymphoma (NHL, n=67) immunohistochemically for the presence of Bcl-2 oncoprotein and P53 protein and compared apoptotic indices (AIs) and Ki-67 proliferative indices (percentages of Ki-67 positive cells). MATERIALS AND METHODS: 67 patients with NHL were evaluated : 3 low-grade and 64 intermediate-grade. The phenotype was determined in 65 cases : 47 (70%) were B cell type and 18 (27%) were T cell type. AIs and Ki-67 proliferative indices were determined immunohistochemically and the overexpression of P53 and Bcl-2 protein were also evalutated. RESULTS: The overexpressions of Bcl-2 protein and P53 protein were found in 40% (26/65) and 31% (20/ 65). The AI ranged from 0% to 15% (mean 2.16, median 1.2). Cellular Bcl-2, which counteracts apoptosis, was significantly ( p=0.005) associated with AIs. Ki-67 proliferative indices ranged from 1% to 91% (mean 55.4), and P53 was significantly ( p=0.000) associated with Ki-67 proliferative indices. A positive correlation between AIs and Ki-67 proliferative indices was revealed ( p=0.012) in Bcl-2 positive patients. CONCLUSION: In NHL, we observed a correlation between AIs and Bcl-2 expression, between Ki-67 proliferative indices and P53 expression, and between AIs and Ki-67 proliferative indices in Bcl-2 positive patients. Our results suggest that cell apoptosis may be inseparable from cell proliferation during tumor growth.

Proliferative Myositis: A Case Report

We report a case of proliferative myositis arising in the pectoralis major muscle of a 59-year-old man who presented with palpable mass. The initial clinical impression was a malignant tumor. Ultrasonography revealed the lesion as a spindle-shaped hypoechoic mass, and MR imaging of the left pectoralis major muscle showed hypointensity at T1-weighted imaging, hyperintensity at T2-weighted imaging, and strong enhancement at contrast-enhanced T1-weighted imaging.

Iron-uptake System of Staphylococcus aureus According to the Antibiotic Susceptibility / 감염

OBJECTIVE: It was reported that a few antimicrobial agents influenced on the activity of bacterial iron- uptake system (IUS). In the present study, we tried to investigate the relatedness between the resistance of antibiotics and the activity of the two high-affinity IUS, siderophore-mediated IUS and transferrin-binding protein (SA-tbp)-mediated IUS, of Staphylococcus aureus clinical isolates. METHODS: Total 71 strains including the standard ATCC 6538 strain were used. Seventy strains were isolated from the second or third line general hospitals from 1998 to 1999. Antimicrobial susceptibility test was performed by disk diffusion method. CAS agar diffusion assay was used for the measurement of staphylococcal siderophore. To visualize the expression of SA-tbp, Western blotting using human transferrin conjugated with horseradish peroxidase was performed. RESULTS: Among the nine antimicrobial agents, only the susceptible strains to oxacillin produced more siderophore compared to the resistant strains (P0.05). There were no antibiotics related to the expression of SA-tbp (P>0.05). CONCLUSION: These results indicate that only oxacillin (OXAC) influences on the production of staphylococcal siderophore and the further consecutive study about the action mechanism of OXAC is necessary.

Adenoid Basal Carcinoma of the Uterine Cervix

We report a case of adenoid basal carcinoma of the uterine cervix unexpectedly found in a 68-year-old female. She was diagnosed with a high-grade squamous intraepithelial lesion (HSIL) on a cervical smear and subsequent cervical punch biopsy. Total abdominal hysterectomy was performed, and there were no significant gross findings in the uterine cervix. Microscopically, the epithelial surface showed a HSIL with glandular extension. Below the neoplastic epithelial lesion were numerous small nests of uniform small cells, which extended to the parametrium. These tumor cells contained hyperchromatic nuclei, inconspicuous nucleoli, and scant cytoplasm. Peripheral palisading and gland-like or acinar structures in the nests were noted. The latter were positive for mucicarmine stain. Foci of squamous differentiation exhibiting occasional mitoses and large atypical cells were seen in the small nests. Stromal reaction was not obvious. Immunohistochemically, the HSIL lesion and adenoid basal carcinoma lesion were negative for human papillowa virus. The tumor cells forming nests were positive for carcinoembryonic antigen, S-100 protein, and high molecular weight cytokeratin, but were negative for -smooth muscle actin and chromogranin A.

Metastatic Cervical Lymphadenopathy from Uterine Leiomyosarcoma with Good Local Response to Radiotherapy and Chemotherapy / 대한방사선종양학회지

The metastasis of uterine leiomyosarcoma to the neck node has not been reported previously and the radiotherapy has been rarely used for the metastatic lesion of the other sites. We report a case of neck metastasis from a uterine leiomyosarcoma, which developed 10 months after surgery and postoperative pelvic radiotherapy. It also involved the parapharyngeal space, adjacent spine, and spinal canal. The metastatic neck mass was inoperable, and was treated by neck radiotherapy (6,000 cGy) and chemotherapy including taxol and carboplatin. The mass has regressed progressively to a nearly impalpable state. She has never developed spinal cord compression syndrome, and has maintained good swallowing for eight months since the neck radiotherapy and chemotherapy. Since the extensive metastatic neck mass showed good local response to high dose radiotherapy and chemotherapy, both treatments may be considered for an unresectable metastatic leiomyosarcoma.

Adult T cell leukemia/lymphoma with lymphopenia in a Korean

We experienced a case of adult T cell leukemia/lymphoma (ATLL) in a 48-year-old Korean female, who has never been abroad since birth and no history of blood transfusion. The patient had hypercalcemia and multiple lymphadenopathy. Histopathologic study of left cervical lymph node (LN) and bone marrow (BM) revealed that infiltrates of malignant lymphoid cells were composed of small, medium and large cells with pleomorphic nuclei. Smears of peripheral blood (PB) showed lymphopenia (16%) with the appearance of a few atypical lymphoid cells (less than 2%), but not the typical clover leaf cells seen in ATLL. Immunophenotypic study of LN and BM revealed T cell phenotype. PB showed increased CD4+ T cell (T(H), CD3/CD4+, 57%) and decreased CD8+ T cell counts (T(S), CD3/CD8+, 6.7%). The sera of the patient and her family were reactive for HTLV-I antibody. The specific sequences of pol, env, and tax of HTLV-I DNA were detected in the lymphoma cells and peripheral blood mononuclear cells (PBMC) using polymerase chain reaction. Ultrastructural examination of PBMC confirmed numerous type c virus particles in extracellular space. This case was an acute type of ATLL without overt leukemic features in PB. Despite chemotherapy and intensive conservative treatment, she died 3 months after admission.

staphylococcus Aureus Growth Inhibition in Amniotic Hluid -Antibody fot the Transferrin-binding Protein- / 대한주산의학회잡지

No abstract available.

Leukemic Phase of Mantle Cell Lymphoma, Blastic Variant / 대한혈액학회지

A case with mantle cell lymphoma, blastic variant, involving the peripheral blood in a 78- year-old female was described. The circulating blast-like cells suggested the possibility of acute leukemia. The WBC count was 28.0x109/ L with the absolute lymphoctyosis, 14.0x109/L. The peripheral blood smears showed a medium to large-sized lymphocytes with blast- like chromatin and conspicuous nucleoli. Atypical cells showing cleaved or indented nucleus were frequently observed. By flow cytometric analysis, immunophenotype of the circulating leukemic cells expressed B-cell associated antigens (CD 19, CD20), coexpressed CD5, lacked CD23, and expressed monoclonal surface immunoglobulin. Bone marrow aspiration and bone core biopsy confirmed diffuse infiltration of lymphoma cells. Immunohistochemicalstain for cyclin D1 (PRAD1/Bcl-1) protein was strongly reactive in the nucleus and cytoplasm of the infiltrative lymphoma cells in the bone marrow. Cytogenetic analysis of the bone marrow aspirates showed the complex abnormalities. Heterotransplantations of the blastic mantle cell leukemic cells, 4x104/microliter, into the peritoneum of the severe combined immunodeficiency (SCID) mouse showed tumor formation and infiltration of malignant lymphoid cells into peritoneum, liver, bone marrow, diaphragm, spinal cord and testes. The histopathology, immunophenotype and cyclin D1 protein expression of xenotransplanted tumor showed identical findings that of the original peripheral blood.

Primary Osteosarcoma of the Breast: A case report

We report a case of primary osteosarcoma of the breast which is rare and exhibits poor prognosis. A 52 years-old-woman was admitted with rapidly growing right mammary mass. A huge lobulated dense mass with speckled calcifications, suggesting malignancy, was observed on mammography. She underwent a radical mastectomy. Grossly, the mass measured 16 14 6 cm and showed grayish white hard lobulated tissue with focal hemorrhage and necrosis. Light microscopically, the tumor was confirmed as an osteosarcoma devoid of any epithelial components. In postoperative whole body bone scan, there was no evidence of the other malignancy. To the best of our knowledge, the present case is the first report of primary osteosarcoma of the breast in Korea.