Showing papers by "Young Jin Suh published in 2018"

Prognostic value of systemic inflammatory markers and development of a nomogram in breast cancer

Abstract: Systemic inflammatory markers derived from peripheral blood cell, such as the neutrophil-lymphocyte ratio (NLR), derived neutrophil-lymphocyte ratio (dNLR), platelet-lymphocyte ratio (PLR) and lymphocyte-monocyte ratio (LMR), have been demonstrated as prognostic markers in several types of malignancy. Here, we investigated and compared the association between systemic inflammatory markers and survival and developed a prognostic nomogram in breast cancer patients. We reviewed the clinical and pathological records of 661 patients diagnosed with invasive breast carcinoma between 1993 and 2011. The NLR, dNLR, PLR and LMR in the immediate preoperative period were assessed. We analyzed the relationship between these inflammatory markers and clinicopathologic variables, disease-specific survival (DSS), and disease-free survival (DFS) in patients. A nomogram was developed to predict 3- and 5-year DSS for breast cancer. In the univariate analysis, high NLR, dNLR, PLR and low LMR were all significantly associated with poor DSS and DFS. In the multivariate analysis, only the PLR (HR 3.226, 95% CI 1.768-5.885 for DSS and HR 1.824, 95% CI 1.824-6.321 for DFS) was still identified as an independent predictor of outcomes. A subgroup analysis revealed that the PLR was the sole independent marker predicting poor DSS in patients with lymph node metastasis (HR 2.294, 95% CI 1.102-4.777) and with luminal subtype (HR 4.039, 95% CI 1.905-8.562). The proposed nomogram, which includes the PLR, shows good accuracy in predicting DSS with a concordance index of 0.82. PLR is an indicator of systemic inflammation as a part of the host immune response. As an independent prognostic factor, an elevated preoperative PLR is superior to the NLR, dNLR, and LMR in predicting clinical outcomes in patients with breast cancer. Moreover, the nomogram incorporating the PLR could accurately predict individualized survival probability in breast cancer.

BRCA1/2-negative, high-risk breast cancers (BRCAX) for Asian women: genetic susceptibility loci and their potential impacts.

Abstract: “BRCAX” refers breast cancers occurring in women with a family history predictive of being a BRCA1/2 mutation carrier, but BRCA1/2 genetic screening has failed to find causal mutations. In this study, we report the findings of the genetic architecture of BRCAX with novel and redefined candidate loci and their potential impacts on preventive strategy. We performed a genome-wide association study involving 1,469 BRCAX cases from the Korean Hereditary Breast Cancer study, and high-risk breast cancer cases (1,482 Asians and 9,902 Europeans) from the Breast Cancer Association Consortium. We also evaluated the previously reported susceptibility loci for their roles in the high-risk breast cancers. We have identified three novel loci (PDE7B, UBL3, and a new independent marker in CDKN2B-AS1) associated with BRCAX, and replicated previously reported SNPs (24 of 92) and moderate/high-penetrance (seven of 23) genes for Korean BRCAX. For the novel candidate loci, evidence supported their roles in regulatory function. We estimated that the common low-penetrance loci might explain a substantial part of high-risk breast cancer (39.4% for Koreans and 24.0% for Europeans). Our study findings suggest that common genetic markers with lower penetrance constitute a part of susceptibility to high-risk breast cancers, with potential implications for a more comprehensive genetic screening test.

Real hypersurfaces in the complex hyperbolic quadrics with isometric Reeb flow

Abstract: We classify real hypersurfaces with isometric Reeb flow in the complex hyperbolic quadrics Q∗m = SO 2,mo/SO mSO2, m ≥ 3. We show that m is even, say m = 2k, and any such hypersurface becomes an open part of a tube around a k-dimensional complex hyperbolic space ℂHk which is embedded canonically in Q∗2k as a totally geodesic complex submanifold or a horosphere whose center at infinity is 𝔄-isotropic singular. As a consequence of the result, we get the nonexistence of real hypersurfaces with isometric Reeb flow in odd-dimensional complex quadrics Q∗2k+1, k ≥ 1.

Synergistic anticancer effects of ruxolitinib and calcitriol in estrogen receptor‑positive, human epidermal growth factor receptor 2‑positive breast cancer cells.

Abstract: The Janus kinase (JAK)1 and JAK2 inhibitor, ruxolitinib, and the active form of vitamin D (calcitriol) were previously reported to possess anticancer effects in breast cancer. The present study investigated the combined effects of ruxolitinib and calcitriol on an estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-positive, breast cancer cell line. The ER and HER2-positive MCF7-HER18 breast cancer cell line was used to investigate the combination effect of ruxolitinib and calcitriol. A bromodeoxyuridine (BrdU) assay was used to investigate cell growth inhibition. The synergism of this combination therapy was examined using the Chou-Talalay method. Cell cycle analysis was performed by flow cytometry, and apoptosis was evaluated by flow cytometry following Annexin V-fluorescein isothiocyanate (FITC) and propidium iodide (PI) staining. Alterations in protein expression levels were analyzed by western blotting. The BrdU assay indicated that combination treatment using ruxolitinib and calcitriol produced a synergistic anti-proliferative effect in MCF7-HER18 breast cancer cells. Annexin V-FITC/PI staining and cell cycle analysis identified a synergistic increase in apoptosis and sub-G1 arrest in the presence of ruxolitinib and calcitriol. Western blot analysis revealed that these synergistic effects of ruxolitinib and calcitriol were associated with reduced protein levels of JAK2, phosphorylated JAK2, c-Myc proto oncogene protein, cyclin-D1, apoptosis regulator Bcl-2 and Bcl-2-like protein 1, and with increased levels of caspase-3 and Bcl-2-associated agonist of cell death proteins. The results of the present study demonstrated the synergistic anticancer effects of ruxolitinib and calcitriol in ER and HER2-positive MCF7-HER18 breast cancer cells. Based on these findings, ruxolitinib and calcitriol may have potential as a combination therapy for patients with ER and HER2-positive breast cancer.

Clinical subtypes and prognosis of pregnancy-associated breast cancer: results from the Korean Breast Cancer Society Registry database.

Abstract: We analyzed the clinicopathologic characteristics and prognosis of pregnancy-associated breast cancer (PABC) according to clinical subtypes to better understand the characteristics of PABC. A total of 83,792 female patients between the ages of 20 and 49 were enrolled in the Korean Breast Cancer Society Registry database from January 1, 1996 to December 31, 2015. ‘PABC’ is defined as breast cancer diagnosed during pregnancy or within 1 year after delivery. Other patients were defined as ‘non-PABC’ patients. In non-PABC patients, luminal A subtype was the most common (50.2%). In PABC patients, TNBC was the most common (40.4%) subtype, while luminal A comprised 21.2% and HER2 subtype comprised 17.3%. There was a significant difference in overall survival (OS). In non-PABC patients, TNBC had the highest HR (HR 2.3, 95% CI 2.1–2.6). In PABC patients, the luminal B subtype (HR+ HER2-high Ki67) had the highest HR at 7.0 (95% CI 1.7–29.1). In multivariate analysis of OS by subtypes, PABC patients had significantly higher HR than non-PABC patients in the HER2 subtype (HR 2.0, 95% CI 1.1–3.7) and luminal B subtype (HR+ HER2-high Ki67) (HR 4.4, 95% CI 1.6–12.3). PABC showed different biologic features than non-PABC. PABC had a particularly poor prognosis in the luminal B (HR+ HER2-highKi67) and HER2 subtypes. To improve the prognosis of PABC, treatment should be considered according to subtype. Development of drugs that can be used during pregnancy is needed.

Derivatives of the Shape Operator of Real Hypersurfaces in the Complex Quadric

Abstract: On a real hypersurface in the complex quadric we can consider the Levi-Civita connection and, for any nonnull constant k, the k-th generalized Tanaka-Webster connection. We also have a differential operator of first order of Lie type associated to the k-th generalized Tanaka-Webster connection. We prove non-existence of real hypersurfaces in the complex quadric for which the covariant derivatives associated to both connections coincide or Lie derivative and Lie type differential operator coincide when they act on the shape operator of the real hypersurface.

Real Hypersurfaces with Killing Shape Operator in the Complex Quadric

Abstract: We introduce the notion of Killing shape operator for real hypersurfaces in the complex quadric $$Q^m = SO_{m+2}/SO_mSO_2$$ . The Killing shape operator condition implies that the unit normal vector field N becomes $$\mathfrak {A}$$ -principal or $$\mathfrak {A}$$ -isotropic. Then according to each case, we give a complete classification of Hopf real hypersurfaces in $$Q^m = SO_{m+2}/SO_mSO_2$$ with Killing shape operator.

Yamabe Solitons on Three-Dimensional N(k)-Paracontact Metric Manifolds

Abstract: We prove that if a three-dimensional N(k)-paracontact metric manifold admits a Yamabe soliton $$(g,\xi )$$ , then the scalar curvature is constant and the manifold is a paraSasakian manifold. Moreover, we show that if a three-dimensional N(k)-paracontact metric manifold admits a Yamabe soliton (g, V), then either the manifold is a space of constant curvature, or the flow vector field V is Killing.

Real Hypersurfaces in the Complex Hyperbolic Quadric with Parallel Normal Jacobi Operator

Abstract: First, we introduce the notion of parallel normal Jacobi operator for real hypersurfaces in the complex hyperbolic quadric $${Q^m}^* = SO_{m,2}/SO_mSO_2$$ . Next we give a complete proof of non-existence of real hypersurfaces in $${Q^m}^* = SO_{m,2}/SO_mSO_2$$ with parallel normal Jacobi operator.

The effect of adjuvant chemotherapy on survival in Korean patients with node negative T1c, triple negative breast cancer.

Abstract: BACKGROUND The present study investigated the prognostic role of adjuvant systemic chemotherapy in patients with node negative, T1c triple negative breast cancer (TNBC) from a nationwide cohort. In addition, the prognostic effect between 3 different chemotherapy regimens were compared in node-negative T1c TNBC patients by subgroup analysis. METHODS From the Korean breast cancer registry database, 1,151 T1c node negative TNBC patients were included in this study. Patients were categorized into four treatment groups according to chemotherapy regimen: (1) no chemotherapy, (2) adriamycin plus cyclophosphamide (AC), (3) adriamycin/epirubicin plus cyclophosphamide plus 5-FU (FAC/FEC), and (4) cyclophosphamide plus 5-FU plus methotrexate (CMF). Overall survival (OS) was evaluated between each patient group. RESULTS Of the 1,151 T1c node negative TNBC patients, 1,006 received adjuvant chemotherapy, while 145 received no chemotherapy. Among the patients receiving adjuvant chemotherapy the distribution of regimens was: 586 AC, 168 FAC/FEC (126 FAC, 42 FEC), and 252 CMF. The mean follow-up time of the full study cohort was 87.98 ± 33.56 months (range = 6-192 months). Patients in the no chemotherapy group showed significantly worse OS compared to each chemotherapy regimen group. However, when OS was compared between each chemotherapy regimen, no significant difference was found. CONCLUSIONS This study showed that adjuvant systemic chemotherapy improved OS in T1c node negative TNBC patients, regardless of chemotherapy between AC, FAC/FEC, and CMF regimens.

Clinical implication of subcategorizing T2 category into T2a and T2b in TNM staging of breast cancer

Abstract: Regarding TNM staging in breast cancer, T2 category is currently not divided into subcategories even though it covers a wider range of tumor sizes than T1 category. Using Korean Breast Cancer Registry database, data of 41 071 women diagnosed as non-metastatic T2 breast cancer between 2001 and 2014 were analyzed. Cutoff value for optimal tumor size was approximated by receiver operating characteristic (ROC) curve to subcategorize T2 tumors. Overall survival (OS) was compared between two subcategories. Median follow-up period was 65 months. Of 41 071 patients, 4504 (11.0%) died. Based on ROC curve analysis, 3.0 cm was selected as the cutoff value. Five-year OS rate was 91% in patients with breast tumors ≤3.0 cm (T2a) and 86% in patients with breast tumors >3.0 cm (T2b) (log-rank P < 0.001). T2b subcategory showed worse OS than T2a subcategory regardless of node status (log-rank P < 0.001 for all node categories). Within every subgroup defined by primary OS analysis covariates, T2b subcategory consistently showed worse outcome compared to T2a subcategory. By multivariate analysis, T2b subcategory was a significant independent prognostic factor of OS (hazard ratio: 1.26, 95% CI = 1.18-1.34). T2 category of breast cancer could be subcategorized into T2a and T2b with a cutoff value of 3 cm. These subcategories definitely showed different OSs even after adjusted for known prognostic factors. Subcategorization of T2 category might be useful for predicting prognosis more accurately and tailoring adjuvant therapy.

Cancer in thyroid nodules with fine-needle aspiration in Korean pediatric populations.

Abstract: Purpose To determine the prevalence and clinical findings of benign thyroid nodules and cancer in Korean pediatric patients with thyroid nodules. Methods We investigated the medical records of 134 patients aged younger than 18 years who had a goiter, thyroid nodule, thyroid mass, or thyroid cancer who underwent fine needle aspiration biopsy (FNAB). Results The study population included 113 females (84.3%) and 21 males (13.7%); the mean patient age was 16.1±2.3 years (range, 8-18 years). Of the 134 patients, 24 (18.0%) were finally diagnosed with thyroid cancer, of which 20 (83.3%) were papillary cancer and 4 (16.7%) were follicular cancer. No patient was exposed to radiation. FNAB revealed malignant cancer in 21 of the patients; 3 were initially reported as having benign tumors by FNAB, but were later diagnosed with follicular cancer. An additional 13 patients were suspected to have malignant tumors by FNAB, with a final diagnosis of nodular hyperplasia. Cystic nodules were more common in the benign group. The percentages of cervical lymphadenopathy and irregular nodular margins were higher in the malignant group compared to the benign group. Cervical lymphadenopathy and FNAB malignant findings were highly suggestive of malignant nodules. Conclusion Thyroid cancer prevalence in a Korean pediatric population is comparable to reported estimates of worldwide thyroid cancer prevalence. In this population, cancer predominates on the right thyroid lobe. Papillary thyroid cancers are dominant in the Korean pediatric population but are less prevalent than in Korean adults. As expected, FNAB was highly accurate in predicting malignant nodules.