Genomic Signature of the Standardized Uptake Value in 18F-Fluorodeoxyglucose Positron Emission Tomography in Breast Cancer

The standardized uptake value (SUV), an indicator of the degree of glucose uptake in 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), has been used for predicting the clinical behavior of malignant tumors. However, its characteristics have been insufficiently explored at the genomics level. Here, we aim to identify genomic signatures reflecting prognostic SUV characteristics in breast cancer (BRC). Through integrative genomic profiling of 3710 BRC patients, including 254 patients who underwent preoperative FDG-PET, we identified an SUV signature, which showed independent clinical utility for predicting BRC prognosis (hazard ratio [HR] 1.27, 95% confidence interval [CI] = 1.12 to 1.45, p = 2.23 × 10-4). The risk subgroups classified by the signature exhibited mutually exclusive mutation patterns of TP53 and PIK3CA and showed significantly different responsiveness to immunotherapy. Experimental assays revealed that a signaling axis defined by TP53-FOXM1 and its downstream effectors in glycolysis-gluconeogenesis, including LDHA, might be important mediators in the FDG-PET process. Our molecular characterizations support an understanding of glucose metabolism and poor prognosis in BRC with a high SUV, utilizable in clinical practice to assist other diagnostic tools.ope

RNF208, an Estrogen-Inducible E3 Ligase, Targets Soluble Vimentin to Suppress Metastasis in Triple-Negative Breast Cancers

The development of triple-negative breast cancer (TNBC) negatively impacts both quality of life and survival in a high percentage of patients. Here, we show that RING finger protein 208 (RNF208) decreases the stability of soluble Vimentin protein through a polyubiquitin-mediated proteasomal degradation pathway, thereby suppressing metastasis of TNBC cells. RNF208 was significantly lower in TNBC than the luminal type, and low expression of RNF208 was strongly associated with poor clinical outcomes. Furthermore, RNF208 was induced by 17β-estradiol (E2) treatment in an estrogen receptor alpha (ΕRα)-dependent manner. Overexpression of RNF208 suppresses tumor formation and lung metastasis of TNBC cells. Mechanistically, RNF208 specifically polyubiquitinated the Lys97 residue within the head domain of Vimentin through interaction with the Ser39 residue of phosphorylated Vimentin, which exists as a soluble form, eventually facilitating proteasomal degradation of Vimentin. Collectively, our findings define RNF208 as a negative regulator of soluble Vimentin and a prognostic biomarker for TNBC cells.ope

Clinical Outcomes Following Letrozole Treatment according to Estrogen Receptor Expression in Postmenopausal Women: LETTER Study (KBCSG-006)

Purpose: In this trial, we investigated the efficacy and safety of adjuvant letrozole for hormone receptor (HR)-positive breast cancer. Here, we report the clinical outcome in postmenopausal women with HR-positive breast cancer treated with adjuvant letrozole according to estrogen receptor (ER) expression levels. Methods: In this multi-institutional, open-label, observational study, postmenopausal patients with HR-positive breast cancer received adjuvant letrozole (2.5 mg/daily) for 5 years unless they experienced disease progression or unacceptable toxicity or withdrew their consent. The patients were stratified into the following 3 groups according to ER expression levels using a modified Allred score (AS): low, intermediate, and high (AS 3-4, 5-6, and 7-8, respectively). ER expression was centrally reviewed. The primary objective was the 5-year disease-free survival (DFS) rate. Results: Between April 25, 2010, and February 5, 2014, 440 patients were enrolled. With a median follow-up of 62.0 months, the 5-year DFS rate in all patients was 94.2% (95% confidence interval [CI], 91.8-96.6). The 5-year DFS and recurrence-free survival (RFS) rates did not differ according to ER expression; the 5-year DFS rates were 94.3% and 94.1%in the low-to-intermediate and high expression groups, respectively (p = 0.6), and the corresponding 5-year RFS rates were 95.7% and 95.4%, respectively (p = 0.7). Furthermore, 25 patients discontinued letrozole because of drug toxicity. Conclusion: Treatment with adjuvant letrozole showed very favorable treatment outcomes and good tolerability among Korean postmenopausal women with ER-positive breast cancer, independent of ER expression. Trial registration: ClinicalTrials.gov Identifier: NCT01069211.ope

Clinical Features of Breast Cancer in South Korean Patients with Germline TP53 Gene Mutations

Purpose: Li-Fraumeni syndrome (LFS) is a rare autosomal cancer syndrome caused by a germline mutation in the TP53 gene. Breast cancer in LFS patients is of various subtypes; however, limited data are available on the clinicopathological features of these subtypes and their appropriate treatments. This study aimed to review the clinical features and treatments for breast cancer in South Korean patients with germline TP53 mutations. Methods: Data on the clinicopathological features and treatment of all breast cancer patients with LFS were collected retrospectively from the available database of 4 tertiary hospitals in the Republic of Korea. Results: Twenty-one breast cancer cases in 12 unrelated women with confirmed germline TP53 mutations were included in the study. The median age at diagnosis was 33.5 years. The histopathological diagnosis included invasive ductal carcinoma (n = 16), ductal carcinoma in situ (n = 3), and malignant phyllodes tumor (n = 2). While 42% and 31% of the cases were positive for estrogen and progesterone receptors, respectively, 52.6% were human epidermal growth factor receptor 2 (HER2) positive, and 21% were triple-negative. The treatments included mastectomy (52%) and breast-conserving surgery (38%). Five patients underwent radiotherapy (RT). The median follow-up period was 87.5 (8-222) months. There were 3 ipsilateral and 4 contralateral breast recurrences during the follow-up, and 8 patients developed new primary cancers. In the post-RT subgroup, there were 2 ipsilateral and 2 contralateral breast recurrences in 1 patient, and 4 patients had a new primary cancer. Conclusion: As reported in other countries, breast cancer in LFS patients in South Korea had an early onset and were predominantly but not exclusively positive for HER2. A multidisciplinary approach with adherence to the treatment guidelines, considering mastectomy, and avoiding RT is encouraged to prevent RT-associated sequelae in LFS patients.ope

A nationwide, multicenter retrospective study on the effectiveness and safety of eribulin in Korean breast cancer patients (REMARK)

Purpose: Approval of eribulin for metastatic breast cancer was based on data primarily from Western patients, and there is a paucity of data on the effectiveness and safety of eribulin for Asian patients. To determine the effectiveness and safety of eribulin in Korean women with breast cancer in a real-world setting, we conducted a nationwide, multicenter, retrospective study. Methods: Patients with locally advanced or metastatic breast cancer who were treated with eribulin in 14 centers throughout Korea were included in this study. Eribulin was generally administered at a dose of 1.23 mg/m2 (equivalent to 1.4 mg/m2 eribulin mesylate) by intravenous infusion for 2-5 min, or as a diluted solution, on Days 1 and 8 of every 21-day cycle. The primary endpoint was progression-free survival (PFS) rate at 6 months. Secondary endpoints included median PFS, overall survival (OS), time-to-treatment failure (TTF), tumor response rate, and incidence of hematologic treatment-emergent adverse events (TEAEs). Results: The safety and full analysis populations included 398 and 360 (38 had no efficacy data) patients, respectively. The PFS rate at 6 months was 37.8%. Median PFS, OS, and TTF were 134, 631, and 120 days, respectively. Objective response rate, clinical benefit rate, and disease control rate were 18.1%, 50.6%, and 49.4%, respectively. Hematologic TEAEs were reported in 65.1% of patients; neutropenia (56.8%) and anemia (11.3%) were most common. Conclusion: Real-world effectiveness and safety of eribulin in Korean breast cancer patients were consistent with previous reports; no new safety concerns were identified.ope

Education Level Is a Strong Prognosticator in the Subgroup Aged More Than 50 Years Regardless of the Molecular Subtype of Breast Cancer: A Study Based on the Nationwide Korean Breast Cancer Registry Database

PURPOSE: This study investigated the role of the education level (EL) as a prognostic factor for breast cancer and analyzed the relationship between the EL and various confounding factors. MATERIALS AND METHODS: The data for 64,129 primary breast cancer patients from the Korean Breast Cancer Registry were analyzed. The EL was classified into two groups according to the education period; the high EL group (≥ 12 years) and low EL group (< 12 years). Survival analyses were performed with respect to the overall survival between the two groups. RESULTS: A high EL conferred a superior prognosis compared to a low EL in the subgroup aged > 50 years (hazard ratio, 0.626; 95% confidence interval [CI], 0.577 to 0.678) but not in the subgroup aged ≤ 50 years (hazard ratio, 0.941; 95% CI, 0.865 to 1.024). The EL was a significant independent factor in the subgroup aged > 50 years according to multivariate analyses. The high EL group showed more favorable clinicopathologic features and a higher proportion of patients in this group received lumpectomy, radiation therapy, and endocrine therapy. In the high EL group, a higher proportion of patients received chemotherapy in the subgroups with unfavorable clinicopathologic features. The EL was a significant prognosticator across all molecular subtypes of breast cancer. CONCLUSION: The EL is a strong independent prognostic factor for breast cancer in the subgroup aged > 50 years regardless of the molecular subtype, but not in the subgroup aged ≤ 50 years. Favorable clinicopathologic features and active treatments can explain the main causality of the superior prognosis in the high EL group.ope

Analysis of risk factors associated with survival in human epidermal growth factor receptor 2-positive ductal carcinoma in situ using Korean Breast Cancer Society Database

Purpose: This study was performed to identify the risk of mortality in patients diagnosed with human epidermal growth factor receptor 2 (HER2)-positive ductal carcinoma in situ (DCIS). Methods: We selected 2,592 patients with HER2-positive DCIS from Korean Breast Cancer Society (KBCS) database between January 1997 and December 2019. Patients who received neoadjuvant chemotherapy were excluded. Logistic regression analysis was used to determine the association between clinical factors and overall death after adjusting for tumor and clinical characteristics. Mortality data were modified using the Statistics Korea data. Results: Thirty deaths (1.2%) were identified out of 2,592 patients in the KBCS database. In the univariate logistic regression analysis, older age, higher body mass index (BMI), type of breast surgery (mastectomy), estrogen receptor-negative, progesterone receptor-negative, and exposure to endocrine therapy were significant clinical factors associated with death. In the multivariate analysis, age (hazard ratio [HR], 1.062; 95% confidence interval [CI], 1.015-1.111; P = 0.006), BMI (HR, 1.179; 95% CI, 1.032-1.347, P = 0.016), breast surgery type (mastectomy vs. lumpectomy; HR, 0.285; 95% CI, 0.096-0.844; P = 0.024), and endocrine therapy (HR, 0.314; 95% CI, 0.099-0.995; P = 0.049) were significant risk factors for mortality. Conclusion: Advanced age, higher BMI, mastectomy, and the absence of endocrine therapy were factors associated with poor survival of patients with HER2-positive DCIS. This finding requires further validation combined with additional analysis of large databases.ope

The Policy Proposal for Effective Prevention and Management of Breast Cancer

Breast cancer is the most common cancer in Korean women since 2001 and needs national interests. The incidence of breast cancer is increasing with new breast cancer cases reaching more than 10,000 cases annually. But, there are some difficulties in breast cancer control; first, the National Cancer Screening Program is ineffective and of low quality, second, the lack of psychosocial care for mastectomized patients, third, the lack of national care for terminal cancer patients. For effective breast cancer control, we need special support for breast cancer awareness campaign, activation of breast cancer registry, development of clinical practice guideline, development of hospice program, breast cancer research, and upgrading its guarantee on breast cancer treatment. The Korean Breast Cancer Society should have the leading role in solving the current problems, but moreover, we cannot overemphasize the need for national support.ope

A phase II study of preoperative capecitabine in women with operable hormone receptor positive breast cancer

Conventional preoperative chemotherapy regimens have only limited efficacy in hormone receptor positive (HR+) breast cancer and new approaches are needed. We hypothesized that capecitabine, which is effective in metastatic breast cancer, may be an active preoperative treatment for HR+ breast cancer. Women with HR+, HER2-negative operable breast cancer received capecitabine, 2000 mg/m2 daily in divided doses for 14 days, followed by a 7-day rest period. Treatment was repeated every 21 days for a total of four cycles. The primary endpoint of the study was to determine the rate of pathological complete response (pCR). Because of slow accrual, the study was closed after 24 patients were enrolled. Three patients had a complete clinical response, and eight patients had a partial clinical response, for an overall clinical response rate of 45.8%. There were no cases of pCR. Of the 22 patients who had pathological response assessment by the Miller–Payne grading system, there were six grade 3 responses, and no grade 4 or 5 responses. Toxicity was manageable: the only grade 3 toxicities observed were one case each of diarrhea, palmar plantar erythrodysesthesia, hypokalemia, and mucositis. There was no association between baseline levels, or change in level from baseline to cycle 1, or from baseline to time of surgery, of thymidine phosphorylase (TYMP), thymidylate synthase (TYMS), dihydropyrimidine dehydrogenase (DPYD), or Ki67 and pathological, clinical, or radiographic response. Preoperative capecitabine is a well-tolerated regimen, but appears not lead to pCR when used as monotherapy in HR+ breast cancer.ope

The association between the expression of nuclear Yes-associated protein 1 (YAP1) and p53 protein expression profile in breast cancer patients

Background: Yes-associated protein 1 (YAP1) is a key effector molecule regulated by the Hippo pathway and described as a poor prognostic factor in breast cancer. Tumor protein 53 (TP53) mutation is well known as a biomarker related to poor survival outcomes. So far clinical characteristics and survival outcome according to YAP1 and TP53 mutation have been poorly identified in breast cancer. Patients and methods: Retrospectively, 533 breast tumor tissues were collected at the Seoul St Mary's hospital and Gangnam Severance Hospital from 1992 to 2017. Immunohistochemistry with YAP1 and p53 specific antibodies were performed, and the clinical data were analyzed. Results: Mutant p53 pattern was associated with aggressive tumor features and advanced anatomical stage. Inferior overall survival (OS) and recurrence free survival (RFS) were related with mutant p53 pattern cases with low nuclear YAP1 expression (P = 0.0009 and P = 0.0011, respectively). Multivariate analysis showed that mutant p53 pattern was an independent prognostic marker for OS [hazard ratios (HR): 2.938, 95% confidence intervals (CIs): 1.028-8.395, P = 0.044] and RFS (HR: 1.842, 95% CIs: 1.026-3.304). However, in cases with high nuclear YAP1 expression, there were no significantly difference in OS and RFS according to p53 staining pattern. Conclusion: We found that mutant p53 pattern is a poor prognostic biomarker in breast tumor with low nuclear YAP1 expression. Our findings suggest that interaction between nuclear YAP1 and p53 expression pattern impact survival outcomes.ope