Soo Youn Bae

Mucinous carcinoma of the breast in comparison with invasive ductal carcinoma: clinicopathologic characteristics and prognosis.

Purpose Mucinous carcinoma (MC) of the breast is a rare histologic type of mammary neoplasm. The objective of this study was to evaluate the long-term disease-free survival (DFS) and overall survival (OS) of MC. Methods We conducted a retrospective analysis of all MC cases reported to a database between 1994 and 2010. Clinicopathological characteristics and survival of 268 MC cases were reviewed and compared with 2,455 invasive ductal carcinoma-not otherwise specified (IDC-NOS) cases. Results The MC cases were of a younger age, involved less lymph nodes, lower stage, more expression of hormonal receptors, and less HER2 overexpression compared to the IDC-NOS cases. The 5-year DFS rate for MC was 95.2% compared to 92.0% for IDC-NOS. The 5-year OS rate for MC was 98.9% compared to 94.9% for IDC-NOS. Multivariate analysis using Cox regression revealed that the mucinous type was a significant prognostic factor for DFS with lower nodal status (N stage) and hormonal therapy. For OS, only N stage was the most significant prognostic factor followed by adjuvant chemotherapy and adjuvant hormonal therapy. Conclusion MC was shown to be associated with a better DFS than IDC-NOS, but it had a similar OS. Nodal status and adjuvant therapy appear to be more significant predictors of prognosis than histologic subtype.

Mutational profiling of brain metastasis from breast cancer: matched pair analysis of targeted sequencing between brain metastasis and primary breast cancer

Although breast cancer is the second most common cause of brain metastasis with a notable increase of incidence, genes that mediate breast cancer brain metastasis (BCBM) are not fully understood. To study the molecular nature of brain metastasis, we performed gene expression profiling of brain metastasis and matched primary breast cancer (BC). We used the Ion AmpliSeq Cancer Panel v2 covering 2,855 mutations from 50 cancer genes to analyze 18 primary BC and 42 BCBM including 15 matched pairs. The most common BCBM subtypes were triple-negative (42.9%) and basal-like (36.6%). In a total of 42 BCBM samples, 32 (76.2%) harbored at least one mutation (median 1, range 0–7 mutations). Frequently detected somatic mutations included TP53 (59.5%), MLH1 (14.3%), PIK3CA (14.3%), and KIT (7.1%). We compared BCBM with patient-matched primary BC specimens. There were no significant differences in mutation profiles between the two groups. Notably, gene expression in BCBM such as TP53, PIK3CA, KIT, MLH1, and RB1 also seemed to be present in primary breast cancers. The TP53 mutation frequency was higher in BCBM than in primary BC (59.5% vs 38.9%, respectively). In conclusion, we found actionable gene alterations in BCBM that were maintained in primary BC. Further studies with functional testing and a delineation of the role of these genes in specific steps of the metastatic process should lead to a better understanding of the biology of metastasis and its susceptibility to treatment.

Smad7 acts as a negative regulator of the epidermal growth factor (EGF) signaling pathway in breast cancer cells

Although it has been suggested that smad7 blocks downstream signaling of TGF-β, the role of smad7 in the EGF signaling pathway has not been fully elucidated. We determined the effect of smad7 on EGF-induced MMP-9 expression in SKBR3 breast cancer cells. The expression of smad7 and MMP-9 was increased by EGF or TGF-β1, respectively, and further increased by EGF and TGF-β1 co-treatment. EGF induced the phosphorylation of EGFR, smad3, ERK, and JNK, and MMP-9 expression was decreased by the EGFR inhibitor, AG1478. In addition, EGF-induced MMP-9 expression was inhibited by UO126 (a MEK1/2 inhibitor) or SIS3 (a smad3 inhibitor), but not by SP600125 (a JNK inhibitor). Interestingly, EGF-induced smad3 phosphorylation was completely blocked by smad7 over-expression, but not the phosphorylation of ERK and JNK. EGF- or TGF-β1-induced MMP-9 expression was completely decreased by adenoviral-smad7 (Ad-smad7) over-expression. We also investigated the role of smad3 on EGF-induced MMP-9 expression and showed that EGF-induced MMP-9 expression was decreased by smad3 siRNA transfection, whereas EGF-induced MMP-9 expression was further increased by smad3 over-expression, as expected. This study showed that EGF-induced smad3 phosphorylation mediates the induction of MMP-9, whereas smad7 inhibits TGF-β1 as well as the EGF signaling pathway in SKBR3 cells.

Berberine Suppresses TPA-Induced Fibronectin Expression through the Inhibition of VEGF Secretion in Breast Cancer Cells

Background/Aims: Berberine (BBR) is an isoquinoline alkaloid and is beneficial for the anticancer effect on a variety of human tumor cells. However, BBRs anti-angiogenesis property and its clinical potential as an inhibitor of tumor angiogenesis in breast cancer cells have not been fully elucidated. Here, we investigated the effect of BBR on TPA-induced VEGF and fibronectin (FN) as well as VEGF-induced FN in breast cancer cells. Methods: The secretion of VEGF protein was detected by ELISA. Fibronectin mRNA and protein expression was analyzed by Real-Time PCR and western blotting, respectively. The overexpressions of CA-MEK, and CA-Akt were examined by adenovirus system. Results: Our results showed that TPA, a tumor promoter, significantly increased the level of VEGF and FN expression in both MCF7 and T47D breast cancer cells. On the other hand, TPA-induced VEGF and FN expression was suppressed by LY294002, a PI-3K inhibitor. In contrast, the level of FN expression also significantly increased by constitutively active (CA)-AKT overexpression. We also found that TPA-induced VEGF and FN expression was decreased by BBR treatment. Finally, our results showed that VEGF augmented the expression of FN whereas VEGF-induced FN expression was decreased by BBR treatment. Conclusion: Taken together, we suggest that BBR may suppress TPA-induced VEGF and FN as well as VEGF-induced FN through the inhibition of the PI-3K/AKT pathway in breast cancer cells. Therefore, we suggest that BBR may be used as a candidate drug for the inhibition of angiogenesis of human breast cancer.

Does Immediate Breast Reconstruction after Mastectomy affect the Initiation of Adjuvant Chemotherapy

Purpose The frequency of immediate breast reconstruction (IBR) is increasing, and the types of reconstruction used are diverse. Adjuvant chemotherapy is a life-saving intervention in selected high-risk breast cancer patients. The aim of our study was to determine how IBR and type of reconstruction affect the timing of the initiation of chemotherapy. Methods We obtained data from female breast cancer patients treated by mastectomy with IBR (IBR group) and without IBR (mastectomy only group) who received adjuvant chemotherapy between January 1, 2008, and December 31, 2010. We retrospectively collected data including patient characteristics, disease characteristics, treatment details, and treatment outcomes from our institutional electronic patient database and medical treatment records. The reconstruction types were categorized as deep inferior epigastric perforator (DIEP) flap, latissimus dorsi (LD) flap and tissue expander/implant (TEI). Results In total, 595 patients were included in this study. Of these patients, 43 underwent mastectomy with IBR (IBR group) and 552 patients did not undergo reconstruction (mastectomy only group). There was significant difference in the timing of the initiation of chemotherapy between the two groups (p<0.0001). There were no cases of delays of more than 12 weeks. In the IBR group, 20 patients received TEI, 9 patients were treated by the insertion DIEP flaps, and 14 patients were treated by LD flaps. There were no significant differences in the timing of chemotherapy according to the type of reconstruction (p=0.095). Conclusion IBR delays the initiation of chemotherapy, but does not lead to omission or significant clinical delay in chemotherapy. Further, the type of reconstruction does not affect the timing of chemotherapy.

Distant, solitary skeletal muscle metastasis in recurrent papillary thyroid carcinoma.

BACKGROUND Papillary thyroid cancer (PTC) is the most common differentiated thyroid carcinoma. Metastases usually occur in regional lymph nodes or to lungs. Distant metastases to skeletal muscle are rare. Here, we report a patient with a solitary metastasis to skeletal muscle. PATIENT FINDINGS A 31-year-old woman was found on routine physical examination to have a 1-cm nodule in the right thyroid lobe. The patient underwent endoscopic total thyroidectomy with central cervical lymph node dissection in April 2008. Pathological analysis showed a 1.5 × 0.9 cm PTC in the right thyroid lobe with extension into perithyroidal soft tissue and lymph node involvement (all six central lymph nodes examined were positive). After surgery, she received 100 mCi of radioactive iodine. Subsequently, the patient was found to have a lateral neck recurrence and, therefore, underwent right unilateral modified radical neck dissection followed by additional radioactive iodine ablation. In February 2010, her serum thyroglobulin was 19.4 ng/mL, but the neck ultrasound was negative. However, a fluorodeoxyglucose (FDG) positron emission tomography scan showed focal FDG uptake in the vastus medialis muscle of the right distal femur. A 0.9 × 0.5 cm, well-defined, whitish mass in the vastus medialis muscle was confirmed on histopathology to be metastatic PTC. SUMMARY Here, we report an adult woman who presented with a thyroid nodule that was noted to be PTC on histopathology after total thyroidectomy. Almost 2 years later, she was noted to have had focal FDG uptake consistent in the region of the right femur. A solitary metastasis of PTC in the right vastus medialis muscle was resected. A MEDLINE (Medical Literature Analysis and Retrieval System Online) search showed that this is only the third report of PTC with a distant, solitary skeletal muscle metastasis. CONCLUSIONS Distant skeletal metastasis in PTC is very rare. Until the availability of FDG to detect skeletal metastasis of PTC, they may have been more difficult to discern.

Long-Term Outcome of Internal Mammary Lymph Node Detected by Lymphoscintigraphy in Early Breast Cancer

Purpose Internal mammary lymph node (IMLN) metastasis is an important prognostic indicator in breast cancer. However, the necessity of internal mammary sentinel lymph node biopsy for accurate staging, for choosing adjuvant treatment, and as a prognostic indicator, has remained controversial. Methods From January 2001 to December 2006, 525 female breast cancer patients underwent radical surgery after preoperative lymphatic scintigraphy. We retrospectively analyzed the follow-up results, recurrences, and deaths of all patients. Results There was no significant difference in the clinicopathological characteristics between the axilla and the IMLN groups. The median follow-up period was 118.8 months (range, 7-122 months) in the axilla group and 107.7 months (range, 14-108 months) in the IMLN group. During the median follow-up period, the breast cancer-related death rate in the axilla group was 3.6%, which was not significantly different from that of the IMLN group (1.3%) (p=0.484). The five-year survival rates did not differ between the two groups (p=0.306). The overall recurrence rate and the locoregional recurrence rate also did not differ between the two groups (p=0.835 and p=0.582, respectively). The recurrence rate of IMLN (both ipsilateral and contralateral) metastasis was very low, accounting for 0.5% in the axilla group and 1.3% in the IMLN group (p=0.416). Conclusion The long-term follow-up results showed that there was no significant difference in both overall outcome and regional recurrence between the two groups. Therefore, the requirement for identification of nodal basins outside the axilla or IMLN sentinel biopsy should be reconsidered.

Immediate postoperative inflammation is an important prognostic factor in breast cancer.

Objective: Inflammation is associated with worse outcomes in cancer. Operations induce an acute inflammatory response and could impact the clinical outcomes in breast cancer. The neutrophil-lymphocyte ratio (NLR) is a well-known indicator of inflammation. We investigated the prognostic significance of perioperative inflammation with the NLR in breast cancer. Methods: We reviewed the clinical and pathological records of women diagnosed with invasive breast carcinoma at the Samsung Medical Center between 2000 and 2010. The NLR levels in the immediate preoperative period and the postoperative periods (1 week and 1 month) were assessed. Results: The NLRs of a total of 3,116 breast cancer patients were examined. In the univariate analysis, the NLR in postoperative week 1, total mastectomy, the presence of lymphovascular invasion, a higher nuclear grade and pathologic TNM stage, and negative hormone receptor and subtypes were factors associated with poor disease-specific survival. The NLR in postoperative week 1 remained a significant prognostic factor in the multivariate analysis. A cutoff level of 5.2, determined by the minimum p value approach, was found to be a significant level for discriminating the impact on breast cancer-specific mortality (p = 0.0116 adjusted by the Bonferroni correction). Conclusions: Immediate postoperative inflammation is an important prognostic marker in breast cancer patients.

Dimerization of EGFR and HER2 induces breast cancer cell motility through STAT1-dependent ACTA2 induction.

The dimerization of EGFR and HER2 is associated with poor prognosis such as induction of tumor growth and cell invasion compared to when EGFR remains as a homodimer. However, the mechanism for events after dimerization in breast cancer models is not clear. We found that expressions of alpha-smooth muscle actin (ACTA2) and signal transducer and activator of transcription 1 (STAT1) significantly increased with transient or stable overexpression of HER2 in EGFR-positive breast cancer cells. ACTA2 and STAT1 expression was also increased in HER2-positive breast cancer patients. In contrast, ACTA2 expression was decreased by HER2 siRNA. Next, we investigated the co-relation between STAT1 and ACTA2 expression. Basal ACTA2 expression was significantly decreased by treatment with the STAT1 inhibitor fludarabine or the JAK2 inhibitor AG490. In contrast, ACTA2 expression was increased by STAT1 overexpression. Levels of ACTA2, STAT1, and HER2 were increased and relapse free survival was decreased in high-risk breast cancer patients. We also investigated the effect of ACTA2 on cell motility, which was suppressed by ACTA2 shRNA overexpression in MDA-MB231 HER2 and 4T1 mammary carcinoma cells. The number of lung metastatic nodules was significantly decreased in ACTA2 knockdown mice. Taken together, these results demonstrated that induction of ACTA2 by EGFR and HER2 dimerization was regulated through a JAK2/STAT1 signaling pathway, and aberrant ACTA2 expression accelerated the invasiveness and metastasis of breast cancer cells.

Adjuvant endocrine therapy alone in patients with node-positive, luminal A type breast cancer

Abstract Luminal A breast cancer has a much better prognosis than other subtypes, with a low risk of local or regional recurrence. However, there is controversy around under- versus overtreatment with regard to adjuvant treatment of node-positive, luminal A breast cancer. The purpose of this study was to identify whether adjuvant systemic chemotherapy has any benefit in node-positive, luminal A breast cancer and to evaluate feasibility of endocrine therapy without chemotherapy in this group. This was a retrospective study of 11,025 patients who were surgically treated for invasive breast cancer at Samsung Medical Center between January 2004 and December 2013. Luminal A subtype was defined as ER+, HER2-, and Ki-67 < 14%. We compared AC based (AC: doxorubicin or epirubicin, plus cyclophosphamide) adjuvant chemotherapy versus endocrine therapy without chemotherapy in patients with node-positive, luminal A breast cancer. We performed 1: n matching, with a maximum n of 8 on endocrine therapy group (n = 50) to chemotherapy group (n = 642). The median age of the patients in each group at the time of surgery was 58.3 ± 9.5 years in the chemotherapy group and 58.7 ± 11.7 in the endocrine therapy only group. The median follow-up time was 51.9 months (range, 1–125 months). In multivariable analysis, omission of adjuvant chemotherapy in luminal A cancer had no influence on OS and DFS. Axillary lymph node metastasis and progesterone receptor (PR) status were significantly different between the endocrine therapy alone group and the chemotherapy group in terms of OS. Nuclear grade, PR status, and adjuvant radiotherapy were significantly different between the endocrine therapy alone group and the chemotherapy group with regard to DFS. In survival analysis, there were no differences in OS (P = .137) and DFS (P = .225) between the 2 groups. Adjuvant chemotherapy could provide little benefit to postmenopausal patients with luminal A, node-positive breast cancer, and endocrine therapy alone may help reduce morbidity. Future studies with a large number of patients and longer follow-up time are necessary to determine whether chemotherapy might be avoided in this patient population.