Diagnostic accuracy of a three-protein signature in women with suspicious breast lesions: a multicenter prospective trial.

BACKGROUND: Mammography screening has been proven to detect breast cancer at an early stage and reduce mortality; however, it has low accuracy in young women or women with dense breasts. Blood-based diagnostic tools may overcome the limitations of mammography. This study assessed the diagnostic performance of a three-protein signature in patients with suspicious breast lesions. FINDINGS: This trial (MAST; KCT0004847) was a prospective multicenter observational trial. Three-protein signature values were obtained using serum and plasma from women with suspicious lesions for breast malignancy before tumor biopsy. Additionally, blood samples from women who underwent clear or benign mammography were collected for the assays. Among 642 participants, the sensitivity, specificity, and overall accuracy values of the three-protein signature were 74.4%, 66.9%, and 70.6%, respectively, and the concordance index was 0.698 (95% CI 0.656, 0.739). The diagnostic performance was not affected by the demographic features, clinicopathologic characteristics, and co-morbidities of the participants. CONCLUSIONS: The present trial showed an accuracy of 70.6% for the three-protein signature. Considering the value of blood-based biomarkers for the early detection of breast malignancies, further evaluation of this proteomic assay is warranted in larger, population-level trials. This Multi-protein Assessment using Serum to deTermine breast lesion malignancy (MAST) was registered at the Clinical Research Information Service of Korea with the identification number of KCT0004847 ( https://cris.nih.go.kr ).

Under- and Normal-Weight Patients Are More Susceptible to Recurrence of Phyllodes Tumor.

Purpose: Phyllodes tumors (PTs) of the breast are rare fibroepithelial neoplasms, and factors associated with the recurrence of PTs are poorly understood. This study sought to identify clinicopathological factors associated with the recurrence of PTs. Method: From January 2009 to December 2019, we identified 100 patients who underwent definitive surgery for PT. Clinicopathological risk factors associated with the recurrence of PT were assessed. Results: The median age of the patients was 44 y (range, 19-62 y), and the median tumor size was 4 cm (0.8-30 cm). At a median follow-up of 26.7 mo (0-103 mo), 22 of the 100 patients experienced local recurrence. In the univariate and multivariate analyses, body mass index ≥ 23 kg/m2 (P = 0.042 in the univariate analysis; P = 0.039 in the multivariate analysis), tumor size ≥ 5 cm (P = 0.006 in the univariate analysis; P = 0.036 in the multivariate analysis), and the presence of stromal overgrowth (P = 0.032 in the univariate analysis; P = 0.040 in the multivariate analysis) were associated with an increased risk of local recurrence. Resection margins and grade were not associated with local recurrence. Conclusion: Normal- or underweight patients and those with larger tumor sizes were more prone to local recurrence. Further larger, multicenter studies with a long-term follow-up are required.

Childbirth in young Korean women with previously treated breast cancer: The SMARTSHIP study.

PURPOSE: Alongside the modern trend of delaying childbirth, the high incidence of breast cancer among young women is causing significant pregnancy-related problems in Korea. We estimated the incidence of childbirth for young Korean breast cancer survivors compared with women who did not have breast cancer using a nationally representative dataset. METHODS: Using a database from the National Health Insurance Service in South Korea, we analyzed 109,680 women who were between 20 and 40 years old between 2007 and 2013. They were prospectively followed, and childbirth events were recorded until December 31, 2015. We compared childbirth rates and characteristics between the breast cancer survivors and the noncancer controls. RESULTS: Compared to 10,164 childbirths among 91,400 women without breast cancer (incidence rate: 22.3/1000), 855 childbirths occurred among 18,280 breast cancer survivors (incidence rate: 9.4/1000); the adjusted hazard ratio (HR) for childbirth was 0.41 (95% CI 0.38-0.44). Chemotherapy, endocrine therapy, and target therapy were associated with the decreasing childbirths among survivors, with corresponding adjusted HRs of 0.61 (0.53-0.70), 0.44 (0.38-0.51), and 0.62 (0.45-0.86), respectively. Breast cancer survivors had a lower probability of full-term delivery and a higher frequency of preterm labor than controls, with corresponding adjusted ORs of 0.78 (0.68-0.90) and 1.33 (1.06-1.65), respectively. CONCLUSIONS: We showed that a history of breast cancer has a negative effect on childbirth among young premenopausal women in Korea. Breast cancer survivors should be aware that they have a higher risk for preterm labor and are less likely to have a full-term delivery than women without a history of breast cancer.

7-O-Methylwogonin from Scutellaria baicalensis Disturbs Mitotic Progression by Inhibiting Plk1 Activity in Hep3B Cells.

Polo-like kinase 1, a mitotic Ser/Thr kinase, has emerged as a molecular target for the development of anticancer drugs. In this study, we found that polo-like kinase 1 activity was inhibited by 7-O-methylwogonin and related flavones, including baicalein, dihydrobaicalein, and viscidulin II, isolated from Scutellaria baicalensis. Although dihydrobaicalein exhibited the highest polo-like kinase 1 inhibitory activity among the four compounds, it also inhibited other kinases, such as vaccinia-related kinase 2 and polo-like kinase 2. Baicalein and viscidulin II also showed low selectivity to polo-like kinase 1 since they inhibited polo-like kinase 3 and polo-like kinase 2, respectively. However, 7-O-methylwogonin exhibited selective polo-like kinase 1 inhibitory activity, as evidenced from in vitro kinase assays based on fluorescence resonance energy transfer assays and ADP-Glo kinase assays. In addition, examination of mitotic morphology and immunostaining using specific antibodies for the mitotic markers, p-histone H3 and mitotic protein monoclonal 2, in Hep3B cells showed that 7-O-methylwogonin treatment increased mitotic cell populations due to inhibition of mitotic progression as a result of polo-like kinase 1 inhibition. The pattern of 7-O-methylwogonin-induced mitotic arrest was similar to that of BI 2536, a specific polo-like kinase 1 inhibitor. Thus, it was suggested that 7-O-methylwogonin disturbed mitotic progression by inhibiting polo-like kinase 1 activity. These data suggest that 7-O-methylwogonin, a polo-like kinase 1 inhibitor, may be a useful anticancer agent because of its polo-like kinase 1 selectivity and effectiveness.

Sensitivity of TP53-Mutated Cancer Cells to the Phytoestrogen Genistein Is Associated With Direct Inhibition of Plk1 Activity.

Polo-like kinase 1 (Plk1), a conserved Ser/Thr mitotic kinase, has been identified as a promising target for anticancer drug development because its overexpression is correlated with malignancy. Here, we found that genistein, an isoflavone, inhibits Plk1 kinase activity directly. Previously the mitotic disturbance phenomenon induced by treatment with genistein was not fully explained by its inhibitory effect on EGFR. In kinase profiling assays, it showed selectivity relative to a panel of kinases, including EGFR. Treatment with genistein induced cell death in a concentration-dependent manner in cancer cells from diverse tissue origins, but not in non-transformed cells such as hTERT-RPE or MCF10A cells. We also observed that genistein tended to be more selective against cancer cells with mutations in the TP53 gene. TP53-depeleted LNCaP and NCI-H460 cells using shRNA targeting human TP53 were more sensitive to cell death by treatment of genistein. Furthermore, genistein induced mitotic arrest by inhibiting Plk1 activity and, consequently, led to mitotic catastrophe and apoptosis. These data suggest that genistein may be a promising anticancer drug candidate due to its inhibitory activity against Plk1 as well as EGFR and effectiveness toward cancer cells, especially those with p53-mutation. J. Cell. Physiol. 232: 2818-2828, 2017. © 2016 Wiley Periodicals, Inc.

Comparison of skin-sparing mastectomy using LigaSure™ Small Jaw and electrocautery.

BACKGROUND: Skin-sparing mastectomy (SSM) is increasingly used in patients with breast cancer. We compared the differences between use of electrocautery and LigaSure™ Small Jaw in patients with breast cancer who underwent SSM. METHODS: Between January 2012 and December 2015, 81 patients with breast cancer who underwent SSM were selected and were divided into the electrocautery group and the LigaSure™ Small Jaw group based on the devices that were used. Clinicopathological characteristics, body mass index, operative time, and weight of removed breast were obtained from medical records. Total amount and days of drain use, until removal, and postoperative skin necrosis, requiring debridement, were also analyzed. RESULTS: The study population consisted of 50 patients in the electrocautery group and 31 in the LigaSure™ Small Jaw group. The latter group has significantly shorter operative time (117.5 ± 16.9 vs. 104.0 ± 23.6 min, P = 0.004). The mean total volume of drainage was less (805 ± 278 vs. 694 ± 131 mL, P = 0.017) and mean duration of drainage was also significantly shorter in the LigaSure™ Small Jaw group (11.3 ± 2.5 vs. 10.1 ± 2.0 days, P = 0.029). CONCLUSIONS: The use of LigaSure™ Small Jaw during skin-sparing mastectomy shortened the operative time and duration of drainage and reduced the total volume of drainage.

Two nuclear export signals of Cdc6 are differentially associated with CDK-mediated phosphorylation residues for cytoplasmic translocation.

Cdc6 is cleaved at residues 442 and 290 by caspase-3 during apoptosis producing p49-tCdc6 and p32-tCdc6, respectively. While p32-tCdc6 is unable to translocate into the cytoplasm, p49-tCdc6 retains cytoplasmic translocation activity, but it has a lower efficiency than wild-type Cdc6. We hypothesized that a novel nuclear export signal (NES) sequence exists between amino acids 290 and 442. Cdc6 contains a novel NES in the region of amino acids 300-315 (NES2) that shares sequence similarity with NES1 at residues 462-476. In mutant versions of Cdc6, we replaced leucine with alanine in NES1 and NES2 and co-expressed the mutant constructs with cyclin A. We observed that the cytoplasmic translocation of these mutants was reduced in comparison to wild-type Cdc6. Moreover, the cytoplasmic translocation of a mutant in which all four leucine residues were mutated to alanine was significantly inhibited in comparison to the translocation of wild-type Cdc6. The Crm1 binding activities of Cdc6 NES mutants were consistent with the efficiency of its cytoplasmic translocation. Further studies have revealed that L468 and L470 of NES1 are required for cytoplasmic translocation of Cdc6 phosphorylated at S74, while L311 and L313 of NES2 accelerate the cytoplasmic translocation of Cdc6 phosphorylated at S54. These results suggest that the two NESs of Cdc6 work cooperatively and distinctly for the cytoplasmic translocation of Cdc6 phosphorylated at S74 and S54 by cyclin A/Cdk2.

Differential Cellular Effects of Plk1 Inhibitors Targeting the ATP-binding Domain or Polo-box Domain.

The expression of polo-like kinase 1 (Plk1) correlates with malignancy and is thus recognized as a target for cancer therapy. In addition to the development of ATP-competitive Plk1 inhibitors, the polo-box domain (PBD), a unique functional domain of PLKs, is being targeted to develop Plk1-specific inhibitors. However, the action mechanisms of these two classes of Plk1 inhibitors have not been thoroughly evaluated. Here, we evaluate the differences in cellular effects of ATP-binding domain inhibitors (BI 2536, GSK 461364) and PBD inhibitors (poloxin, thymoquinone) to determine their mechanisms of Plk1 inhibition. Our data show that BI 2536 and GSK461364 increased the population of cells in the G2/M phase compared with controls, while treatment with poloxin and thymoquinone increased cell population in the S phase as well as in G2/M, in a p53-independent manner. The population of cells staining positively for p-Histone H3 and MPM2, mitotic index, was increased by treatment with BI 2536 or GSK461364, but not by treatment with poloxin or thymoquinone. Furthermore, treatment with BI 2536 or GSK461364 resulted in activation of the BubR1 spindle checkpoint kinase, suggesting that treatment with ATP-binding domain inhibitors induces metaphase arrest. However, the administration of poloxin and thymoquinone resulted in an increase in p21(WAF1) and S arrest, indicating that PBD inhibitors also affected interphase before mitotic entry. Taken together, these data suggest that the PDB of Plk1 plays a role in S phase progression through interaction with other proteins, while its ATP-binding domain is important for regulating mitotic progression mediated by its catalytic activity involving consumption of ATP.

Robotic thyroidectomy using bilateral axillo-breast approach: Comparison of surgical results with open conventional thyroidectomy.

BACKGROUND: The aim of the present study was to compare the surgical outcomes of robotic thyroidectomy using the bilateral axillo-breast approach (BABA) with open conventional thyroidectomy. METHODS: Database of patients who underwent thyroidectomy with cervical lymph node dissection after diagnosed as papillary thyroid carcinoma between July 2008 and February 2013 were examined. Clinicopathologic characteristics, surgical outcomes, and postoperative morbidities of robot group and open group were investigated. RESULTS: The dominant tumor size (P=0.974), body mass index (BMI) (P=0.426), and the mean number of metastatic lymph nodes in central compartment neck dissection (P=0.269) were comparable between the two groups. The mean number of retrieved central lymph nodes was higher in the open group than in the robot group (P=0.001). Postoperative complications were comparable: hypoparathyroidism in 2 weeks (P=0.296) and 3 months (P=0.446) after the surgery; vocal cord palsy in 2 weeks (P=0.363) and 3 months (P=0.312); hematoma (P=0.162); and wound infection (P=0.421). CONCLUSIONS: Robotic thyroidectomy using BABA may be a technically feasible and safe procedure comparable to conventional open surgery especially in node-negative patients.

Transoral periosteal thyroidectomy: cadaver to human.

BACKGROUND: Although endoscopic thyroid surgery is gaining wide acceptance, existing endoscopic methods for thyroidectomy are blamed for the increased frequency of flap dissections and longer surgical times. More recently, transoral endoscopic thyroidectomy has overcome the limitations of previous approaches. Herein, we present our initial experience with transoral periosteal thyroidectomy (TOPOT) in cadaver and porcine models. Using these models, the surgical view was improved and had greater freedom of motion; the technique was then performed in human subjects using robotic TOPOT, which has not previously been reported. METHOD: TOPOTs were performed in seven fresh human cadavers and ten live pigs. Total thyroidectomies were performed in all cadavers and pigs. After the cadaver and animal trials, four human patients underwent robotic TOPOT performed using the da Vinci® surgical system at Korea University Anam Hospital. Recurrent laryngeal nerve function, intra- and postoperative complications, and postoperative outcomes were assessed in all patients. RESULT: One left lobectomy for follicular adenoma, two right lobectomies for nodular hyperplasia, and one left lobectomy with a central neck dissection for papillary thyroid microcarcinoma were performed in the human subjects using a robotic transoral periosteal approach. In three cases, paresthesia occurred in the mental nerve, but this improved within 4 weeks in all cases. No local infections occurred at the incision site or anterior neck, and no recurrent laryngeal nerve cord palsies occurred postoperatively. CONCLUSION: TOPOT may be an effective and safe approach for robotic thyroid surgery.

YKL-40 expression could be a poor prognostic marker in the breast cancer tissue.

YKL-40 is a glycoprotein involved in cellular growth, migration, and the inflammatory process. Elevation in serum levels of YKL-40 has been associated with worse prognosis in various cancers, including breast cancer. Given that the clinical significance of YKL-40 expression in breast cancer tissue is unclear, we aimed to determine the prognostic value of YKL-40 expression in breast cancer tissue using immunohistochemistry. We performed tissue microarray (TMA) analysis of 425 breast cancer tissues collected during operation. Immunohistochemical staining was performed to measure expression of YKL-40 and several breast cancer biomarkers, such as aldehyde dehyadrogenase1, TGF-beta, and Gli-1 as well as hormonal receptor and Her-2/neu status. Statistical analysis of the relationship of YKL-40 expression with clinicopathological characteristics was performed for 390 TMA samples. YKL-40 was expressed to varying degrees in 84.9% of breast cancer tissues. YKL-40 expression was correlated with estrogen receptor and progesterone receptor negativity and was positively correlated with TGF-beta and Gli-1 expression. Strong YKL-40 expression was associated with a larger proportion of Her-2/neu-enriched and basal-like tumors. The results of this study demonstrate that YKL-40 expression in breast cancer tissues is associated with hormone receptor negativity and Her-2/neu-enriched molecular subtypes of breast cancer, and therefore could be considered a poor prognostic predictor.

Synergistic effect of simvastatin plus NS398 on inhibition of proliferation and survival in hepatocellular carcinoma cell line.

BACKGROUND AND AIMS: NS398, a selective cyclooxygenase-2 inhibitor, and simvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, both exert an anticancer effect on hepatocellular carcinoma cells, but the effect of co-administration of the two drugs remains unknown. We aimed to investigate the synergistic in vitro anticancer effect of co-administration of NS398 and simvastatin and its mechanism. METHODS: The Hep3B and Huh-7 cell lines were cultured. Cells were treated with simvastatin, NS398, or a combination. 5-bromo-2'-deoxyuridine ELISA assay, flow cytometry, Western blot analyses, and immunofluorescence assay were performed. RESULTS: In both cell lines, co-administration of simvastatin and NS398 resulted in a greater effect on proliferation and apoptosis. In Hep3B cells, co-administration of the two drugs resulted in a greater decrease in procaspase 3 and Bcl-2 and an increase in cleaved caspase 9 than that noted with monotherapy. In Huh-7 cells, co-administration of the two drugs resulted in a greater decrease in procaspase 3 and cyclin D1 and an increase in cleaved caspase 9. Expression of NF-κB and Akt were also decreased to a greater extent when the two drugs were co-administered in both cell lines. Immunofluorescence assay showed suppression of the nuclear localization of NF-κB by simvastatin or NS398. The effect was greater by co-administration. CONCLUSIONS: The co-administration of NS398 and simvastatin produced greater antiproliferative and proapoptotic effects against Hep3B cells and Huh-7 cells. Inhibition of the NF-κB and Akt pathway and activation of caspase cascade, which are considered as the major mechanism of synergistic anticancer properties, were observed in both cell lines.

Predictive value of urinary and serum biomarkers in young children with febrile urinary tract infections.

BACKGROUND: Early predictive biomarkers for the diagnosis and management of febrile urinary tract infections (UTIs) can be valuable diagnostic tools in children. METHODS: The study cohort comprised 73 pediatric patients with febrile UTIs [46 with acute pyelonephritis (APN) and 27 with lower UTIs] and 56 healthy children. Urine neutrophil gelatinase-associated lipocalin (uNGAL) and kidney injury molecule-1 (uKIM-1) levels and serum cystatin C (sCysC) levels were measured. RESULTS: The uNGAL/creatinine (Cr) and uKIM-1/Cr levels were higher in the UTI group than in the controls (P < 0.05). uNGAL/Cr and sCysC levels were higher in patients with APN than in those with lower UTIs (P < 0.05). uNGAL/Cr levels in both the APN and UTI groups decreased following the administration of antibiotics compared to those before treatment (P < 0.05). The uNGAL/Cr level was correlated with serum levels of white blood cells, C-reactive protein, CysC and with uKIM-1/Cr (P < 0.05). uKIM-1/Cr was also correlated with sCysC (P < 0.05). Receiver operating curve analyses showed good diagnostic profiles of uNGAL/Cr and uKIM-1/Cr for identifying UTIs [area under the curve (AUC) 0.9 and 0.66, respectively) and of uNGAL/Cr and sCysC for predicting APN (AUC 0.78 and 0.72, respectively). CONCLUSIONS: Our results suggest that uNGAL, uKIM-1 and sCysC levels may be useful for predicting and managing febrile UTIs in children.

Safe and successful pregnancy following breast cancer treatment in young patients 35 years old or under without invasive fertility preservation: a retrospective study.

Purpose: Recent advances in the treatment of breast cancer have led to the improvement of breast cancer patient's survival. With the prolonged survival of these patients, pregnancy became an important issue, especially in young cancer patient aged 35 years or under. Increased hormone levels during pregnancy, however, raise concerns about elevating the risk of cancer recurrence. The aim of this study was to validate the notion of increased risk associated with pregnancy after breast cancer treatment in young patients. Methods: From January 2009 to December 2020, newly diagnosed breast cancer patients 35 years old or under who underwent optimal surgery in Korea University Guro Hospital were enrolled in this study. Patients were categorized into 3 groups: nulliparous, pregnancy prior to treatment of breast cancer, and patients with pregnancy after breast cancer treatment. Their overall survival and disease-free survival were evaluated. Results: A total of 107 patients were enrolled in this study. Thirteen patients (12.1%) conceived and successfully delivered. The mean follow-up period after surgery was 58.9 (± 33.5) months. There was no significant difference in overall survival (P = 0.608) and disease-free survival (P = 0.591) among different groups. Conclusion: In young patients, pregnancy after treatment for breast cancer did not affect their overall survival or diseasefree survival as compared to nullipara or previously delivered groups. Therefore, pregnancy counseling should not be prevented in young breast cancer patients 35 years old or under.

Phosphorylation of Cdc6 at serine 74, but not at serine 106, drives translocation of Cdc6 to the cytoplasm.

Phosphorylation-dependent cytoplasmic translocation of human Cdc6 during S phase is sufficient to control its activity after origin firing. Export from the nucleus also serves as a mechanism for preventing re-replication in mammalian cells. Phosphorylation of the CDK consensus serine residues 54, 74, and 106 has been suggested to be involved in the cytoplasmic translocation of Cdc6. To determine the relative importance of the three phosphorylation sites, we have generated Cdc6 variants by substituting one or more of the three serine residues with alanine or aspartic acid and have assessed their cytoplasmic translocation behavior. Phosphorylation of serine 74 mainly contributes to the cytoplasmic translocation of Cdc6, while serine 54 phosphorylation provides a minor contribution. In contrast, phosphorylation at serine 106 does not affect the nuclear export of Cdc6. Comparative results were found in cells coexpressing the phosphorylation defective mutants of Cdc6 and cyclin A as well as in non-transfected cells synchronized by their release from a double thymidine block. We conclude that Cdk-mediated phosphorylation of Cdc6 at serine 74 is required for the cytoplasmic translocalization of Cdc6 during the cell cycle. Phosphorylation of Cdc6 at serine 54 plays a minor role and phosphorylation of serine 106 plays no role in the cytoplasmic localization of Cdc6. The phosphorylation of S74 in Cdc6 could be important for binding to the nuclear export protein for translocalization.

The relationship between preeclampsia, pregnancy-induced hypertension and maternal risk of breast cancer: a meta-analysis.

BACKGROUND: It has long been recognized that some human breast cancers are hormone dependent. Preeclampsia is a syndrome of pregnancy defined by the onset of hypertension and proteinuria and characterized by dysfunction of the maternal endothelium. Many hormonal changes occur with preeclampsia, and we hypothesize that these changes may influence the risk of maternal breast cancer. We also analyzed the relation between pregnancy-induced hypertension (PIH) and maternal risk of breast cancer. METHODS: Among 13 relevant publications about preeclampsia and six relevant publications about PIH, some studies find preeclampsia associated with a lower risk of breast cancer, but others did not. Therefore, these results are inconclusive. We conducted meta-analysis to evaluate more precisely the relationship between preeclampsia, PIH and maternal risk of breast cancer. RESULTS: The pooled estimate of the hazard ratio (HR) associated with preeclampsia was 0.86 (95% CI 0.73-1.01), and that associated with PIH was 0.83 (0.66-1.06), both based on the random effects model. CONCLUSION: Some suggestive but not entirely consistent nor conclusive evidence was found on the association between the history of preeclampsia or PIH with the subsequent risk of breast cancer.

Epidemiology of Second Non-breast Primary Cancers among Survivors of Breast Cancer: A Korean Population-Based Study by the SMARTSHIP Group.

PURPOSE: This study aimed to evaluate the incidence and prognosis of second non-breast primary cancer (SNBPC) among Korean survivors of breast cancer. Materials and Methods: Data from the Korean National Health Insurance Service were searched to identify women who received curative surgery for initial breast cancer (IBC) between 2003 and 2008 (n=64,340). Among them, patients with the following characteristics were excluded: other cancer diagnosis before IBC (n=10,866), radiotherapy before IBC (n=349), absence of data on sex or age (n=371), or male (n=248). Accordingly, data of 52,506 women until December 2017 were analyzed. SNBPC was defined as a newly diagnosed SNBPC that occurred 5 years or more after IBC diagnosis. RESULTS: The median follow-up time of all patients was 12.13 years. SNBPC was developed in 3,084 (5.87%) women after a median of 7.61 years following IBC diagnosis. The 10-year incidence of SNBPC was 5.78% (95% confidence interval [CI], 5.56 to 6.00). Higher SNBPC incidence was found in survivors with the following factors: old age at IBC diagnosis, low household income, and receiving combined chemotherapy with endocrine therapy, whereas receiving radiotherapy was related to a lower incidence of SNBPC (hazard ratio, 0.89; p < 0.01). Among the patients with SNBPC, the 5-year survival rate was 62.28% (95% CI, 65.53 to 69.02). CONCLUSION: Approximately 5% of breast cancer survivors developed SNBPC within 10 years after IBC diagnosis. The risk of SNBPC was associated with patient's age at IBC diagnosis, income level, and a receipt of systemic treatments.

The relationship between twin births and maternal risk of breast cancer: a meta-analysis.

Women who undergo a greater number of menstrual cycles may be at increased risk of breast cancer, possibly due to cumulative exposure to ovarian hormones. Pregnancy reduces the lifetime number of menstrual cycles and also influences the levels of ovarian hormones. Twin pregnancies differ from singleton pregnancies in both hormone levels and perinatal changes. To date, a meta-analysis on the effects of twin birth on the risk of maternal breast cancer has not been conducted. Among 17 relevant publications identified in a systematic search, some suggest that twin births may be associated with lower breast cancer risk but others do not; therefore, the results are inconclusive. Although our pooled results of all 17 published studies did not show a reduced maternal risk of breast cancer for twin births (HR 0.94; 95% CI = 0.87-1.02; P = 0.127), a trend toward reduced maternal risk of breast cancer was identified in a subgroup analysis of cohort studies (HR 0.91; 95% CI = 0.83-1.01; P = 0.068). The results of this meta-analysis suggest that twin pregnancy does not significantly decrease the maternal risk of breast cancer.

Association of a vascular endothelial growth factor gene 936 C/T polymorphism with breast cancer risk: a meta-analysis.

Published studies on the association between the vascular endothelial growth factor (VEGF) gene 936 C/T polymorphism and breast cancer risk are inconclusive, and a meta-analysis is required to verify the association. Nine studies, including a total of 4,973 cases and 5,035 controls, were subjected to meta-analysis. When all eligible subjects were pooled for meta-analysis, the CT + TT genotypes were not associated with a significant decrease in breast cancer risk (odds ratio = 0.87; 95% confidence interval 0.75-1.02; P = 0.087). We also categorized by ethnicity (Caucasian, Asian, or mixed) for subgroup analysis, however, according to this subgroup analysis, we found no significant association between the CT and TT versus CC genotype with breast cancer risk reduction in any of the subgroups. We conclude that the VEGF gene 936 C/T polymorphism does not affect breast cancer risk.