Long-term exposure to air pollution and precocious puberty in South Korea

BACKGROUND AND AIM

The increasing prevalence of precocious puberty (PP) has emerged as a significant medical and social problem worldwide. However, research on the relationship between long-term air pollution exposure and PP has been relatively limited. We thus investigated the association between long-term air pollution exposure and the onset of PP in South Korea.

METHODS

We investigated a retrospective cohort using the Korea National Health Insurance Database. Six-year-old children born from 2007 to 2009 were examined (2013-2015). We included boys ≤10 years and girls aged ≤9 years who visited hospitals for early pubertal development, were diagnosed with PP per the ICD-10 (E228, E301, and E309), and received gonadotropin-releasing hormone agonist treatment. We analyzed data for boys up until 10 years old (60-month follow-up) and for girls up to 9 years old (48-month follow-up). We assessed the association between long-term air pollution exposure and the onset of PP using a Cox proportional hazard model. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) per 1 μg/m3 increase in fine particulate matter (PM2.5) and particulate matter (PM10) and per 1 ppb increase in sulfur dioxide (SO2), nitrogen dioxide (NO2), and ozone (O3).

RESULTS

This study included 1,205,784 children aged six years old between 2013 and 2015. A positive association was found between the 48-month moving average PM2.5 (HR: 1.019; 95% CI: 1.012, 1.027), PM10 (HR: 1.009; 95% CI: 1.006, 1.013), SO2 (HR: 1.037; 95% CI: 1.018, 1.055), and O3 (HR: 1.006; 95% CI: 1.001, 1.010) exposure and PP in girls but not boys.

CONCLUSIONS

This study provides valuable insights into the harmful effects of air pollution during childhood and adolescence, emphasizing that air pollution is a risk factor that should be managed and reduced.

A Case of Chromosome 17q12 Deletion Syndrome with Type 2 Mayer-Rokitansky-Küster-Hauser Syndrome and Maturity-Onset Diabetes of the Young Type 5

Chromosome 17q12 deletion syndrome (OMIM #614527) is a rare genetic disorder associated with a heterozygous 1.4-1.5 Mb deletion at chromosome 17q12, leading to a spectrum of clinical manifestations, including kidney abnormalities, neurodevelopmental delay, maturity-onset diabetes of the young type 5 (MODY5), and Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome. We present the case of a 14-year-old Korean female diagnosed with chromosome 17q12 deletion syndrome, confirmed by chromosomal microarray analysis. The patient exhibited MODY5 with pancreatic agenesis, MRKH syndrome, dysmorphic facial features, developmental delay, kidney rotation anomaly, portal vein thrombosis with liver hypoplasia, short stature, and scoliosis. Management involved the initiation of multiple daily insulin injections for diabetes control, gynecological evaluation for MRKH syndrome, and multidisciplinary care for associated complications. This case highlights the complexity and varied organ involvement in chromosome 17q12 deletion syndrome. A comprehensive and multidisciplinary approach is crucial for the management of affected individuals, including regular monitoring, tailored interventions across various medical specialties, and providing psychosocial support.

Multidisciplinary Shared Decision Making for Fertility Preservation in Young Women With Breast Cancer

PURPOSE

Fertility preservation (FP) is an important issue for young survivors of breast cancer. Although international guidelines recommend pre-treatment fertility counseling for women with breast cancer, there is no standardized protocol or referral system for FP in South Korea. There are also barriers to discussing FP that make patient-centered decision making difficult. This study aimed to develop a shared decision making program for FP and compare the rates of FP procedures between the usual care and shared decision making groups. We hypothesized that multidisciplinary shared decision making for FP would increase the rate of FP procedures and patient satisfaction.

METHODS

The multidisciplinary shared decision making for FP in young women with breast cancer (MYBC) is a multicenter, clustered, stepped-wedge, randomized trial. A total of 1100 patients with breast cancer, aged 19-40 years, from nine hospitals in South Korea, will be enrolled. They will be randomized at the institutional level and assigned to usual care and shared decision making groups. Four institutions, each of which can recruit more than 200 patients, will each become a cluster, whereas five institutions, each of which can recruit more than 50 patients, will become one cluster, for a total of five clusters. The shared decision making groups will receive multidisciplinary programs for FP developed by the investigator. The primary outcome is the rate of FP procedures; secondary outcomes include fertility results, satisfaction, and quality of life. Outcomes will be measured at enrollment, treatment initiation, and the 1-, 3-, and 5-year follow-ups after starting breast cancer treatment.

DISCUSSION

A multidisciplinary shared decision making program for FP is expected to increase fertility rates and satisfaction among young patients with breast cancer. This study will provide the evidence to implement a multidisciplinary system for patients with breast cancer.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05139641. Registered on December 1, 2021.

Metabolic complications of obesity in children and adolescents

The global prevalence of childhood and adolescent obesity, exacerbated by the COVID-19 pandemic, is affecting not only school-aged children but also preschoolers. Early-onset obesity, along with a higher risk of metabolic complications, may contribute to a lower age of onset of cardiovascular disease (CVD). As metabolic diseases such as diabetes, dyslipidemia, and non-alcoholic fatty liver disease (NAFLD) observed in adulthood are increasingly recognized in the pediatric population, there is an emphasis on moving disease susceptibility assessment from adulthood to childhood for early detection. Unlike adults, there is a lack of consensus in the definition of metabolic diseases in children. In response to this, various indicators such as pediatric simple metabolic syndrome score (PsiMS), continuous metabolic syndrome score (cMetS), single point insulin sensitivity estimator (SPISE), and fatty liver index (FLI) have been proposed in several studies. These indicators may help explain and early detect metabolic complications associated with pediatric obesity, although more validity studies are needed. Meanwhile, obesity assessment is shifting its perspective from visual obesity to metabolic health and body composition considerations to fill the gap in health impact assessment. Sarcopenic obesity, defined as muscle-to-fat ratio (MFR), has been proposed in pediatric populations and has also been found to be associated with metabolic health in children and adolescents. The National health screening program for children in Korea has expanded but still faces limitations in laboratory testing. These tests facilitate timely intervention by identifying high-risk groups for metabolic complications. Early detection and intervention through comprehensive health screening are critical to mitigate long-term complications of childhood obesity.

Clinical characteristics and prognosis of postpartum breast cancer

PURPOSE

Postpartum breast cancer (PPBC) is a not well-established subset of breast cancer, and only few studies address its poorer prognosis. However, previous studies show that PPBC is associated with worse outcome with higher rates of metastasis than in young women's breast cancer (YWBC). We aimed to analyze the clinical characteristics and prognosis of PPBC based on the diagnosis period of PPBC.

METHODS

We retrospectively reviewed 208,780 patients with breast cancer from the Korean Breast Cancer Society registry (KBCSR) database between January 2000 and December 2014. We included premenopausal women aged 20-50 years who underwent breast cancer surgery. The patients were classified by 5-year intervals according to the diagnosis period of breast cancer, from the first birth to the breast cancer diagnosis.

RESULTS

Compared with patients in the other groups, patients diagnosed within postpartum 5 years (PPBC < 5 years) group were younger, had a more advanced stage, had lower estrogen receptor (ER) and progesterone receptor (PR) expression, and had a higher human epidermal growth factor receptor 2 (HER2) positive rate. Further, PPBC < 5 years group had a worse survival rate than the nulliparous and other groups (5-year cumulative survival: PPBC < 5 years group, 89%; nulliparous group, 97.3%; 5 ≤ PPBC < 10 years group, 93%). In the multivariate analysis, the PPBC < 5 years group was associated with a worse survival rate (hazard ratio 1.55, 95% confidence interval [CI] 1.148-2.094, p 0.004) after adjustment for age at diagnosis, breast cancer stage, ER and HER2 status, Ki-67 level, and chemotherapy.

CONCLUSION

Our findings indicated that patients diagnosed with breast cancer within the first 5 years after delivery had aggressive characteristics and a poor survival rate. It is important to elucidate the pathophysiology of PPBC and establish novel therapeutic strategies to improve the survival rate.

Increase of Prevalence of Obesity and Metabolic Syndrome in Children and Adolescents in Korea during the COVID-19 Pandemic: A Cross-Sectional Study Using the KNHANES

(1) Background: The aim of this study was to evaluate the prevalence of obesity and metabolic syndrome since the COVID-19 pandemic outbreak utilizing representative data on youth aged 2-18 years from the Korean National Health and Nutrition Examination Surveys (KNHANES) conducted in 2019-2020. (2) Methods: The survey consists of three parts: health interviews, health examinations, and nutrition surveys. From the 2019 and 2020 surveys, 1371 (2-9 years = 702 and 10-18 years = 669) and 1124 (2-9 years = 543 and 10-18 years = 581) individuals were included in the analysis. (3) Results: The mean body mass index (BMI) increased significantly among youth aged 2-9 years from 16.53 kg/m² in 2019 to 17.1 kg/m² in 2020 (p < 0.01). In youth aged 10-18 years, the BMI was found to increase slightly from 21.25 kg/m² in 2019 to 21.41 kg/m² in 2020 (p = 0.64). The increasing prevalence of extreme obesity was significant in girls, especially those aged 2-9 years (p < 0.01). However, extreme obesity had increased in 10-18-year-old boys (p = 0.08). The overall prevalence of metabolic syndrome in adolescents increased from 3.79% to 7.79% during the COVID-19 pandemic (p = 0.01). (4) Conclusions: We observed that the prevalence of obesity and metabolic syndrome among children and adolescents has increased after the COVID-19 outbreak. This is believed to be associated with an increase in the rate of early comorbidities in adulthood. The prevention of the progression of pediatric obesity has recently become an urgent public health concern in Korea.

Breast Cancer Statistics in Korea, 2019

This article provides an annual update of Korean breast cancer statistics, including the incidence, tumor stage, type of surgical treatment, and mortality. The data was collected from the Korean Breast Cancer Society registry system and Korean Central Cancer Registry. In 2019, 29,729 women were newly diagnosed with breast cancer. Breast cancer has continued to increase in incidence since 2002 and been the most common cancer in Korean women since 2019. Of the newly diagnosed cases in 2019, 24,820 (83.5%) were of invasive carcinomas, and 4,909 (16.5%) were of carcinoma in situ. The median age of women with breast cancer was 52.8 years, and breast cancer was most commonly diagnosed in the age group of 40-49 years. The number of patients who have undergone breast conserving surgery has continued to increase since 2016, with 68.6% of patients undergoing breast conserving surgery in 2019. The incidence of early-stage breast cancer continues to increase, with stage 0 or I breast cancer accounting for 61.6% of cases. The most common subtype of breast cancer is the hormone receptor-positive human epidermal growth factor receptor 2-negative subtype (63.1%). The 5-year relative survival rate of patients with breast cancer from 2015 to 2019 was 93.6%, with an increase of 14.3% compared to that from 1993 to 1995. This report improves our understanding of breast cancer characteristics in South Korea.

Prediction of Oncotype DX Recurrence Score Using Clinicopathological Variables in Estrogen Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Breast Cancer

PURPOSE

Oncotype DX (ODX) is a well-validated multigene assay that is increasingly used in Korean clinical practice. This study aimed to develop a clinicopathological prediction (CPP) model for the ODX recurrence scores (RSs).

METHODS

A total of 297 patients (study group, n = 175; external validation group, n = 122) with estrogen receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative, T1-3N0-1M0 breast cancer, and available ODX test results were included in the study. Risk categorization as determined by ODX RSs concurred with the TAILORx study (low-risk, RS ≤ 25; high-risk, RS > 25). Univariate and multivariate logistic regression analyses were used to assess the relationships between clinicopathological variables and risk stratified by the ODX RSs. A CPP model was constructed based on regression coefficients (β values) for clinicopathological variables significant by multivariate regression analysis.

RESULTS

Progesterone receptor (PR) negativity, high Ki-67 index, and nuclear grade (NG) 3 independently predicted high-risk RS, and these variables were used to construct the CPP model. The C-index, which represented the discriminatory ability of our CPP model for predicting a high-risk RS, was 0.915 (95% confidence interval [CI], 0.859-0.971). When the CPP model was applied to the external validation group, the C-index was 0.926 (95% CI, 0.873-0.978).

CONCLUSION

Our CPP model based on PR, Ki-67 index, and NG could aid in the selection of patients with breast cancer requiring an ODX test.

Risk factors for level V metastasis in patients with N1b papillary thyroid cancer

BACKGROUND

Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer, and its incidence has increased. Lateral lymph node metastasis (LLNM) implies a worse prognosis than central lymph node metastasis, with a higher recurrence rate and decreased disease-free survival. The 2015 American Thyroid Association guidelines recommend compartmental node dissection in patients with LLNM to reduce the risk of recurrence and mortality. The purpose of this study was to identify the risk factors for level V lymph node (LN) metastasis in patients with N1b papillary thyroid cancer (PTC).

METHODS

A total of 110 consecutive patients who underwent total thyroidectomy with lateral neck dissection for PTC between April 2016 and April 2022 were retrospectively enrolled. Based on level V metastasis, 94 patients were divided into two groups, and their clinicopathological characteristics were compared. Univariable analysis were used to assess the factors associated with level V metastasis. Spearman correlation analysis were used to assess the correlation between tumors and LN. The receiver operating characteristic (ROC) curve was used to determine the optimal cutoff value for the number of metastatic LNs at each level for level V metastasis.

RESULTS

The number of metastatic LNs and lymph node ratio (LNR) in level II were significantly associated with level V metastasis (P = 0.011 and 0.001, respectively). The number of metastatic LNs in level II and those in the total number of levels correlated with the number of metastatic LNs in level V (rho = 0.331, 0.325, and P = 0.001, 0.001, respectively). The cutoff value for the number of metastatic LNs in level II was defined as 2.5 (area under the curve = 0.757, sensitivity = 50%, specificity = 82.5%, 95% confidence interval [CI] 0.626-0.889, P = 0.002). Simultaneous 3-level metastasis (level II, III, and IV) and 3-level with ≥ 2.5 metastatic LNs in level II were significantly associated with level V metastasis (P = 0.003 and 0.002).

CONCLUSIONS

The number of metastatic LNs and LNR in level II, simultaneous 3-level metastasis (level II, III, and IV), and 3-level with ≥ 2.5 metastatic LNs in level II were significantly associated with level V metastasis. (P = 0.011, 0.001, 0.003, and 0.002, respectively). In the future, larger-scale multi-institutional studies were needed to find out predictors for level V metastasis.

Clinicopathological features and prognosis associated with breast cancer laterality: a nationwide study from the Korean Breast Cancer Society

Purpose

Although breast cancer is known to show a left predominance, the clinical characteristics and causes underlying this finding remain unclear. In addition, no related studies on breast cancer laterality have been conducted in patients with breast cancer in Korea. Therefore, we aimed to analyze differences in breast cancer laterality and the associated clinicopathological characteristics and prognosis among Korean patients with breast cancer.

Methods

We conducted a retrospective analysis using large-scale data on clinicopathological factors and prognosis differences related to breast cancer laterality from the Korean Breast Cancer Society Registration system. The left-to-right ratio (LRR) of breast cancer was calculated through binomial distribution, and factors related to breast cancer laterality were identified through logistic regression analysis. In addition, the differences in the survival rates for left and right breast cancers were analyzed using the Kaplan-Meier method and Cox proportional hazards model.

Results

In 171,500 patients, the LRR was 1.031 (95% confidence interval, 1.022-1.041; P < 0.001). Multivariate analysis showed that the ratio of left breast cancer was related to age, body mass index (BMI), location, and human epidermal growth factor receptor 2 (HER2) status. The survival rate of patients with left and right breast cancers showed no significant difference.

Conclusion

A large-scale analysis revealed a left predominance in breast cancer laterality in Korean patients. Over time, this predominance gradually decreased. Age, BMI, location, and HER2 status affected breast cancer laterality. However, while left breast cancer showed relatively aggressive characteristics, it was not associated with a difference in the survival rate.

Characteristics and Prognosis of Estrogen Receptor Low-Positive Breast Cancer

Purpose

The updated American Society of Clinical Oncology/College of American Pathologists guideline for estrogen receptor (ER) testing recommends that breast cancer with ER expression in 1–10% of tumor cells should be reported as ER-low positive (ER^low), although limited data are available on the overall benefits of endocrine therapy. We investigated the clinicopathological characteristics and clinical outcomes of ER^low breast cancer and to compare them with those of ER-negative (ER^neg) and ER-high (> 10% of tumor cells, ER^high) breast cancers.

Methods

Consecutive patients with invasive breast cancer who underwent curative surgery between November 2007 and December 2014 were included. Clinicopathological characteristics and disease-free survival (DFS) of ER^low tumors were compared with those of ER^neg and ER^high tumors.

Results

Of the 2,309 cases included, 46 (2%), 643 (27.8%), and 1,620 (70.2%) were ER^low, ER^neg, and ER^high, respectively. ER^low tumors were associated with no special type of histology (p = 0.011), advanced pT (p = 0.017), pN (p = 0.009) and anatomic stages (p < 0.001), high grade (p < 0.001), negative/low progesterone receptor (PR) status (p < 0.001), human epidermal growth factor receptor 2 positivity (p < 0.001), high Ki-67 (p < 0.001), and recurrence (p = 0.006) compared to ER^high tumors. DFS was significantly dependent on ER status, and ER^low tumors showed poorer DFS than ER^high tumors (p = 0.001), however, there was no significant survival difference between ER^low and ER^neg tumors. Furthermore, DFS in ER^high patients was affected by hormone therapy (p < 0.001), while it was not affected in ER^low patients.

Conclusion

Patients with ER^low breast cancer have clinicopathological characteristics that differ from those with ER^high tumors. Although this study was limited by the small sample size of the ER^low group, no benefit from hormone therapy was observed in the ER^low group compared with the ER^high group.

Low incidence of lymph node metastasis in patients with microinvasive breast cancer: a Korean nationwide study

Purpose

Microinvasive breast cancer (MIBC) is an invasive carcinoma with a tumor dimension not exceeding 1 mm. Owing to its low incidence, the rate of axillary node metastasis and its management are not well established. The aim of this study was to assess the incidence of lymph node metastasis (LNM) and identify variables associated with LNM, as well as to evaluate the need for axillary staging in MIBC patients by analyzing nationwide data.

Methods

The Korean Breast Cancer Society registry was searched to identify MIBC patients diagnosed between January 1996 and April 2020. Patients without neoadjuvant chemotherapy experiences, systemic metastasis, and missing or discordant data were eligible for the analysis. The incidence rate of LNM was determined, and variables associated with LNM were identified by multivariable regression analysis.

Results

Of 2,427 MIBC patients identified, 98 (4.0%) had LNM and 12 (0.5%) had N2/3 disease. Type of breast operation (odds ratio [OR], 2.093; 95% confidence interval [CI], 1.332–3.290; P = 0.001), age (OR, 2.091; 95% CI, 1.326–3.298; P = 0.002), hormone receptor status (OR, 2.220; 95% CI, 1.372–3.594; P = 0.001), and lymphovascular invasion (OR, 11.143; 95% CI, 6.354–19.540; P < 0.001) were significantly related to LNM.

Conclusion

The incidence of LNM in MIBC patients was only 4.0% in our study, suggesting that de-escalation of axillary surgical interventions could be carefully considered. The indications for axillary staging should be individualized considering tumor volume, age, hormone receptor status, and lymphovascular invasion to improve the quality of life of MIBC survivors.

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.

Clinical impact of radioactive iodine dose selection based on the number of metastatic lymph nodes in patients with papillary thyroid carcinoma: A multicenter retrospective cohort study

OBJECTIVE

The aim of this study is to investigate whether the number of metastatic lymph nodes (LNs) could be used as a basis in the radioactive iodine (RAI) dose selection for patients with papillary thyroid carcinoma (PTC).

PATIENTS

A total of 595 patients with PTC who received first RAI therapy after total or near-total thyroidectomy and had no evidence of disease in treatment response assessment were retrospectively enroled from five hospitals. The patients were classified into two subgroups based on the number of metastatic LNs (>5). The multivariate Cox-proportional hazard model was performed to identify the significant factors for recurrence prediction in each group as well as all enroled patients.

RESULTS

Overall, 22 (3.7%) out of 595 patients had the recurrent disease during the follow-up period. The number of metastatic LNs (>5) was only a significant factor for recurrence prediction in all enroled patients (odds ratio: 7.834, p < .001). In the subgroup with ≤5 metastatic LNs, the presence of extrathyroidal extension was only associated with recurrence (odds ratio: 7.333, p = .024) in multivariate analysis. RAI dose was significantly associated with recurrence rate in which the patients with high-dose RAI (3.7 GBq or higher) had less incidence of recurrence than those with low-dose RAI (1.11 GBq) in the subgroup with more than five metastatic LNs (odds ratio: 6.533, p = .026).

CONCLUSIONS

High-dose RAI (≥3.7 GBq) therapy significantly lowered the recurrence rate in patients with more than five metastatic LNs. Therefore, RAI dose should be determined based on the number of metastatic LNs as well as conventional risk factors.

Deep learning models for screening of high myopia using optical coherence tomography

This study aimed to validate and evaluate deep learning (DL) models for screening of high myopia using spectral-domain optical coherence tomography (OCT). This retrospective cross-sectional study included 690 eyes in 492 patients with OCT images and axial length measurement. Eyes were divided into three groups based on axial length: a “normal group,” a “high myopia group,” and an “other retinal disease” group. The researchers trained and validated three DL models to classify the three groups based on horizontal and vertical OCT images of the 600 eyes. For evaluation, OCT images of 90 eyes were used. Diagnostic agreements of human doctors and DL models were analyzed. The area under the receiver operating characteristic curve of the three DL models was evaluated. Absolute agreement of retina specialists was 99.11% (range: 97.78–100%). Absolute agreement of the DL models with multiple-column model was 100.0% (ResNet 50), 90.0% (Inception V3), and 72.22% (VGG 16). Areas under the receiver operating characteristic curves of the DL models with multiple-column model were 0.99 (ResNet 50), 0.97 (Inception V3), and 0.86 (VGG 16). The DL model based on ResNet 50 showed comparable diagnostic performance with retinal specialists. The DL model using OCT images demonstrated reliable diagnostic performance to identify high myopia.

Comparison of clinicopathological characteristics and prognosis in breast cancer patients with different Breast Imaging Reporting and Data System categories

Purpose

The Breast Imaging Reporting and Data System (BI-RADS) is a systematic and standardized scheme of the radiological findings of breast. However, there were different BI-RADS categories between breast cancers as the clinical characteristics in previous studies. We analyzed the association of BI-RADS categories with the clinicopathological characteristics and prognosis of breast cancer.

Methods

A total of 44,184 patients with invasive breast cancers assigned to BI-RADS category 3, 4, or 5 in preoperative mammography or ultrasonography were analyzed retrospectively using large-scale data from the Korean Breast Cancer Society registration system. The difference in the clinicopathological factors and prognoses according to the BI-RADS categories (BI-RADS 3–4 and BI-RADS 5) were compared between the mammography and ultrasonography groups. Comparisons of the clinicopathological factors in both groups were made using logistic regression analysis, while the prognoses were based on the breast cancer-specific survival using the Kaplan-Meier method and Cox proportional hazards model.

Results

The factors associated with BI-RADS were T stage, N stage, palpability, histology grade, and lymphovascular invasion in the mammography group; and N stage, palpability, histology grade, and lymphovascular invasion in the ultrasonography group. In the survival analysis, there were significant differences in the breast cancer-specific survival of the BI-RADS category groups in both of the mammography (hazard ratio [HR], 3.366; P < 0.001) and ultrasonography (HR, 2.877; P < 0.001) groups.

Conclusion

In this study, the BI-RADS categories of preoperative mammography and ultrasonography of patients with invasive breast cancer were associated with prognosis and could be an important factor in making treatment decisions.

Immunohistochemical Expressions of Senescence-Associated Secretory Phenotype and Its Association With Immune Microenvironments and Clinicopathological Factors in Invasive Breast Cancer

This study was undertaken to investigate immunohistochemical expression of the senescence-associated secretory phenotype (SASP) in invasive breast cancer (IBC) tissues and to determine relationships between SASP positivity and tumor microenvironments and the clinicopathological characteristics of IBC. Immunohistochemistry for senescence markers, that is, high mobility group box-1 (HMGB1), p16, p15, and decoy receptor 2 (DCR2), was performed in tissue microarrays of 1140 IBC samples. Cases positive for at least one of these four markers were considered SASP-positive. Relations between SASP and tumor characteristics, including immune microenvironments (stromal tumor-infiltrating lymphocytes [sTILs] density and numbers of intraepithelial CD103-positive [iCD103 + ] lymphocytes) and clinical outcomes were retrospectively evaluated. HMGB1, p16, p15, or DCR2 was positive in 6.7%, 26.6%, 21.1%, and 26.5%, respectively, of the 1,140 cases. Six hundred and five (53.1%) cases were SASP positive, and SASP positivity was significantly associated with histologic grade 3, high-sTIL and iCD103 + lymphocyte counts, absence of ER or PR, and a high Ki-67 index. Although SASP did not predict breast cancer-specific survival (BCSS) or disease-free survival (DFS) in the entire cohort, SASP positivity in luminal A IBC was associated with poor BCSS and DFS. However, patients with SASP-positive TNBC showed better survival than those with SASP-negative TNBC. In multivariate analysis, SASP positivity was an independent prognostic factor in both luminal A IBC and TNBC, although the effect on prognosis was the opposite. In conclusion, SASP would be involved in the modulation of immune microenvironments and tumor progression in IBC, and its prognostic significance depends on molecular subtype.

Response to neoadjuvant chemotherapy based on pathologic complete response in very young patients with ER-positive breast cancer: a large, multicenter, observational study

Background

In estrogen receptor (ER)-positive breast cancer (BC), young age is associated with poor prognosis. While very young patients respond better to chemotherapy, chemotherapy is less effective in ER-positive tumors than in ER-negative tumors. The authors tried to evaluate chemotherapy response of very young patients with ER-positive BC by pathologic complete response (pCR) after neoadjuvant chemotherapy excluding the effect of endocrine treatment to the extent possible.

Methods

We collected individual patient data from 1992 to 2013 from the Korean Breast Cancer Society (KBCS). Total 1048 ER-positive and 797 ER-negative patients aged < 50 years who had been treated with neoadjuvant chemotherapy were included for analysis. We compared pCR rate between patients aged < 35 years with ER-positive tumors and the other groups.

Results

The proportion of patients aged < 35 years was 14.0% of patients with ER-positive BC in this cohort of under 50 years old, and 16.8% of patients with ER-negative BC in this cohort of under 50 years old. Although most characteristics of tumors according to age were comparable, tumors with high Ki-67 expression were more common in patients aged < 35 years than in patients aged 35-49 years in both ER-positive and -negative group (P = 0.001). Breast conservation rates were not significantly different according to age (44.2% vs. 46.8% in ER-positive group, 55.2% vs. 48.0% in ER-negative group). pCR rate was not different according to age in ER-positive group (P = 0.71) but significantly better in patients aged < 35 years in ER-negative group (P = 0.009). After adjusting for confounding variables, young patients maintained the higher probability of pCR than older patients in ER-negative tumors. However, pCR rate did not differ according to age in ER-positive tumors. In multivariate analysis, young age (< 35 years) was correlated with poor overall survival (P = 0.003, HR = 1.98) and there was only one event in a few patients achieved pCR in ER-positive group.

Conclusions

Chemotherapy response based on pCR was not better in young patients (< 35 years) with ER-positive BC than in older premenopausal patients with non-metastatic ER-positive BC. Young age cannot be a predictive factor of response to neoadjuvant chemotherapy in ER-positive BC. Different biological characteristics such as high proliferative index should be considered.

Trial registration

Retrospectively registered.

Analysis of the Molecular Signature of Breast Implant-Associated Anaplastic Large Cell Lymphoma in an Asian Patient

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL)—a new category of anaplastic large cell lymphoma associated with textured breast implants—has a distinct variation in incidence and is especially rare in Asia. We report the first case of BIA-ALCL in Korea and present its histological and genetic characteristics. A 44-year-old female patient presented with a typical clinical course and symptoms, including breast augmentation with textured breast implants, late-onset peri-implant effusion, and CD30⁺ALK⁻ histology, followed by bilateral implant removal and total capsulectomy. For histological analysis, we performed immunohistochemistry of the bilateral breast capsules. For transcriptome analysis, we identified highly upregulated gene sets employing RNA-sequencing and characterized the lymphoma immune cell components. In the lymphoma-associated capsule, CD30⁺ cells infiltrated not only the lymphoma lesion but also the peritumoral lesion. The morphologies of the myofibroblasts and vessels in the peritumoral lesion were similar to those in the tumoral lesion. We observed strong activation of the JAK/STAT3 pathway and expression of programmed death ligand-1 in the lymphoma. Unlike the molecular profiles of BIA-ALCL samples from Caucasian patients—all of which contained activated CD4⁺ T cells—the Asian patient’s profile was characterized by more abundant CD8⁺ T cells. This study contributes to a better understanding of the pathogenesis and molecular mechanisms of BIA-ALCL in Asian patients that will ultimately facilitate the development of clinical therapies.

Level of Evidence: 5

Recurrence prediction for breast phyllodes tumours: validation of the Singapore nomogram in Korean women

AIM

The Singapore nomogram was developed to predict recurrence risk of phyllodes tumours (PTs) of the breast based on histological features of stromal atypia, stromal mitoses, stromal overgrowth and surgical margin status. We aimed to validate the utility of the Singapore nomogram in a Korean PT cohort.

METHODS

One hundred and twenty-four patients with Korean PT who underwent surgical resection between 1996 and 2015 were included in this study. Pathology reports and slides were reviewed to obtain histopathologic features and acquire Singapore nomogram scores. The probability of concordance between predicted and observed survivals by means of the Singapore nomogram was evaluated using a concordance index (C-index).

RESULTS

Of the 124 cases, 57 (46%) were diagnosed as benign, 50 (40.3%) as borderline and 17 (13.7%) as malignant. Recurrences occurred in 25 (20.2%) patients. Univariate analysis showed PTs with higher stromal mitotic counts, marked stromal cellularity, stromal overgrowth, positive surgical margin, marked stromal atypia or a malignant grade presented higher risks of recurrence. Multivariate analysis showed stromal mitoses and surgical margin status independently predicted recurrence-free survival. Patients with high nomogram scores were at greater risk of recurrence (HR=1.05, 95% CI: 1.02 to 1.07, p<0.001) with a C-index of 0.762.

CONCLUSION

The Singapore nomogram provided a useful means of predicting PT outcomes in a Korean PT cohort.

Repeat Sentinel Lymph Node Biopsy for Ipsilateral Breast Tumor Recurrence After Breast Conserving Surgery With Sentinel Lymph Node Biopsy: Pooled Analysis Using Data From a Systematic Review and Two Institutions

Introduction: Best surgical approach of axillary staging remains controversial in locally recurrent breast cancer. We evaluated the reliability of repeat sentinel lymph node biopsy (reSLNB) in patients with ipsilateral breast tumor recurrence (IBTR) after breast conserving surgery (BCS) with sentinel lymph node biopsy (SLNB) in terms of identification rate (IR) and false negative rate (FNR). To address the FNR, we identified patients who underwent sequential axillary lymph node dissection (ALND) after reSLNB.

Methods: A systematic search of PubMed, EMBASE, and Cochrane Library were conducted to identify patient-level data from articles. We searched for data of patients who underwent BCS with SLNB for primary breast cancer and who underwent sequential ALND after reSLNB due to local recurrence. Patients data was also identified by the same criteria at two institutions.

Results: In total, 197 peer-reviewed publications were obtained, of which 20 included patients who met the eligibility criteria. Data from 464 patients were collected. From the two institutions, 31 patients were identified. A total of 495 patients were pooled. The IR of reSLNB was 71.9% (356/495). To address the FNR of reSLNB, 171 patients who underwent ALND after reSLNB were identified. The FNR and accuracy of reSLNB were 9.4% (5/53) and 97.1% (165/170), respectively.

Conclusion: Our pooled data analysis showed that the FNR of reSLNB is lower than 10%, indicating that this operation is a reliable axillary surgery in patients with IBTR after they underwent BCS.

Impact of the Updated Guidelines on Human Epidermal Growth Factor Receptor 2 (HER2) Testing in Breast Cancer

Purpose

In 2007, the American Society of Clinical Oncology and the College of American Pathologists had established a human epidermal growth factor receptor 2 (HER2) testing guideline, which was updated in 2013 and subsequently in 2018. We assessed the clinical impact of the recent update by comparing the in situ hybridization (ISH) results based on the 2007, 2013, and 2018 guidelines.

Methods

We assessed 2 cohorts. The first cohort included 1,161 primary invasive breast cancer (IBC) samples including 18 bilateral IBC cases, with both immunohistochemistry (IHC) and silver-enhanced ISH (SISH) results available for the HER2 status. The second cohort included 160 IBC cases with equivocal HER2 IHC, assessed using SISH. We retrospectively evaluated and compared the HER2 SISH results.

Results

There were 22 (1.9%) and 20 (12.5%) cases with altered SISH results according to the 2013 guidelines in cohorts 1 and 2, respectively. As per the 2018 guidelines, final HER2 statuses of 16 (1.4%) and 14 (8.5%) cases changed in cohorts 1 and 2, respectively. The 2013 guidelines increased the positive rate compared to the 2007 guidelines, in both cohorts (0.6% and 6.2%, respectively). Most equivocal cases in cohorts 1 (92.3%) and 2 (100%) as per the 2013 guidelines were reclassified as HER2-negative according to the 2018 guidelines. The 2018 guidelines increased the negative rates (1.3% in cohort 1 and 8.7% in cohort 2) and slightly decreased the positive rates (−0.2% in cohort 1 and −3.1% in cohort 2), compared to the 2013 guidelines. With each update, minor changes in the positive and negative rates were observed in whole breast cancer samples (cohort 1). However, the 2018 guidelines affected previously defined HER2-positive IBC with equivocal IHC results.

Conclusion

Under the 2013 guidelines, the positive and equivocal cases increased. However, the 2018 guidelines eliminated ambiguous cases by reclassifying them as HER2-negative.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Psychoacoustics and neurophysiological auditory processing in patients with Charcot-Marie-Tooth disease types 1A and 2A

BACKGROUND AND PURPOSE

Hidden hearing loss has been reported in patients with Charcot-Marie-Tooth (CMT) disease; however, the auditory-processing deficits have not been widely explored. We investigated the psychoacoustic and neurophysiological aspects of auditory processing in patients with CMT disease type 1A (CMT1A) and type 2A (CMT2A).

METHODS

A total of 43 patients with CMT1A and 15 patients with CMT2A were prospectively enrolled. All patients with CMT disease had normal sound-detection ability by using pure-tone audiometry. Spectral-ripple discrimination, temporal modulation detection and auditory frequency-following response were compared between CMT1A, CMT2A and control groups.

RESULTS

Although all participants had normal audiograms, patients with CMT disease had difficulty understanding speech in noise. The psychoacoustic auditory processing was somewhat different depending on the underlying pathophysiology of CMT disease. Patients with CMT1A had degraded auditory temporal and spectral processing. Patients with CMT2A had no reduced spectral resolution, but they showed further reduced temporal resolution than the patients with CMT1A. The amplitudes of the frequency-following response were reduced in patients with CMT1A and CMT2A, but the neural timing remained relatively intact.

CONCLUSIONS

When we first assessed the neural representation to speech at the brainstem level, the grand average brainstem responses were reduced in both patients with CMT1A and CMT2A compared with healthy controls. As the psychoacoustic aspects of auditory dysfunctions in CMT1A and CMT2A were somewhat different, it is necessary to consider future auditory rehabilitation methods based on their pathophysiology.

The effectiveness of prophylactic ipsilateral central neck dissection in selected patients who underwent total thyroidectomy for clinically node-negative unilateral papillary thyroid carcinoma

Background

Prophylactic central neck dissection (CND) in clinically node-negative (cN0) papillary thyroid carcinoma (PTC) remains controversial. The purpose of this study was to evaluate the benefits of prophylactic ipsilateral CND compared with bilateral CND in total thyroidectomy for cN0 unilateral PTC.

Methods

We retrospectively enrolled 174 patients who underwent total thyroidectomies with prophylactic CND for cN0 unilateral PTC between January 2009 and May 2010. The prophylactic CND patients were divided into group 1, the ipsilateral CND group (n=74), and group 2, the bilateral CND group (n=100). The incidence of central lymph node metastasis (CLNM) and postoperative complications, such as hypoparathyroidism, recurrent laryngeal nerve injury, and recurrence were assessed.

Results

CLNM was found in 22 (29.8%) in group 1 and 69 (69%) in group 2. The incidence of postoperative severe hypocalcemia less than 7.0 was also significantly different (six patients [8.1%] in group 1 and 23 [23%] in group 2; p=0.009). Permanent hypoparathyroidism was significantly more frequent in group 2 (4.1% vs. 19%; p=0.005). However, the incidence of transient hypoparathyroidism, recurrence, and recurrent laryngeal nerve injury was not significantly different.

Conclusion

Prophylactic ipsilateral CND has advantage not only to reduce incidence of some complications but also to have similar recurrence rate compared with bilateral CND. We suggest that prophylactic ipsilateral CND may be safe and effective for selected patients undergoing total thyroidectomy for cN0 unilateral PTC.

Abstract P3-08-13: Prognostic significance of intraepithelial CD103-positive tumor-infiltrating lymphocytes in breast cancer

Cluster of differentiation 103 (CD103), also known as αEβ7 integrin, is expressed on subsets of CD8+ T lymphocytes and a biomarker for tissue resident memory CD8+ T cells (TRM). CD103 expression is upregulated upon antigen recognition concurrent with transforming growth factor β (TGFβ) stimulation. CD103 is primarily expressed in the intra-epithelial tumor-infiltrating lymphocytes (iTILs) compared with that in stromal TILs (sTILs). Here, we investigated the prognostic significance of CD103+ iTILs in invasive breast cancer (IBC). Immunohistochemistry was performed for CD103, TGFβ isoforms (1, 2, and 3), and TGFβ receptors on tissue microarrays of 1173 IBC samples. CD103 expression was analyzed using Aperio ScanScope slide scanner. An area with the highest density of CD103+ iTILs was captured at a magnification of × 200, and CD103+ iTILs per unit area (mm2) were enumerated. The threshold for CD103+ iTILs (high vs low) was determined based on the mean number. Immunohistochemical staining for TGFβ isoforms (1, 2, and 3) and their receptors was quantitated using H-score and calculated as: staining intensity (0-3) × the percentage of positive tumor cells (0-100%). For statistical analyses, we categorized cases as positive or negative based on the mean value of H-score. The number of CD103+ iTILs were compared with clinicopathological characteristics, and tumor cell expression of TGFβ and its receptors. Further, the relationship between CD103+ iTILs density and prognosis was investigated according to the molecular subtypes. CD103+ iTILs were observed in 713 (60.8%) cases with a mean ± standard deviation of 34.2 ± 94.6. Increased abundance of CD103+ iTILs was found to be significantly associated with histological grade 3, high Ki-67 labelling index, non-luminal subtypes, high sTIL density, and positive expression of TGFβ3 and its receptor (all, P&lt; 0.001). Furthermore, high CD103+ iTIL density was significantly associated with prolonged overall survival (OS) (P = 0.02) and disease-free survival (DFS) (P = 0.001). Subgroup analysis according to molecular subtypes showed that CD103+ iTILs was prognostic only for triple-negative breast cancer (OS, P = 0.003; DFS, P = 0.005). Multivariate analysis of CD103+ iTILs with clinicopathological prognostic factors revealed that CD103+ iTILs was an independent prognostic factor for OS (P = 0.005) and DFS (P = 0.006) for the triple-negative subtype. Our study revealed that breast cancer cell expression of TGFβ3 may be involved in recruitment of CD103+ iTILs. In breast cancer, CD103+ iTILs indicates good prognosis which is an independent favorable prognostic factor in patients with triple negative subtype and more reliable than sTIL density.

Citation Format: Young Kyung Bae, Min Hui Park, Jung Eun Choi, Su Hwan Kang, Gyungyub Gong. Prognostic significance of intraepithelial CD103-positive tumor-infiltrating lymphocytes in breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P3-08-13.

Usefulness of 1-year of thyroid stimulating hormone suppression on additional levothyroxine in patients who underwent hemithyroidectomy with papillary thyroid microcarcinoma

Background

The purpose of this study was to identify usefulness of 1-year of thyroid stimulating hormone (TSH) suppression, on additional levothyroxine in patients who underwent hemithyroidectomy with papillary thyroid microcarcinoma (PTMC).

Methods

Two-hundred consecutive patients who had received hemithyroidectomy February 2011 to March 2013, were enrolled, retrospectively. Group 1, only, was taking levothyroxine for a year, postoperatively. We evaluated postoperative hypothyroidism through serum TSH level, measured periodically.

Results

Postoperative TSH >10 was significantly different, at 13% and 25%, between two groups (P=0.036). Twenty patients in group 1, and 32 patients in group 2, received additional levothyroxine. Multivariate analysis showed that 1-year suppression, clinical thyroiditis, and preoperative TSH >2, were significantly associated with additional levothyroxine (OR 2.17, P=0.025 and OR 2.00, P=0.046 and OR 2.64, P=0.006). Too, 1-year TSH suppression, preoperative TSH >2, were also significantly associated with postoperative TSH >10 (OR 2.55, P=0.022 and OR 2.22, P=0.048).

Conclusions

We suggest 1-year TSH suppression after hemithyroidectomy, for PTMC in patients with preoperative TSH >2 mU/L and clinical thyroiditis, to reduce additional levothyroxine.

Clinical and biological significance of EZH2 expression in endometrial cancer

The objective of this study was to examine the clinical significance of EZH2 expression and the therapeutic efficacy of its silencing in endometrial cancer. EZH2 expression in clinical samples was evaluated using a tissue microarray and correlated with clinical outcomes. The biological roles of EZH2 were assayed in vitro and in vivo. Gene expression was examined to reveal the molecular mechanism underlying the roles of EZH2 in endometrial cancer. We found that EZH2 overexpression was significantly correlated with disease-free and overall survival of patients with endometrial cancer. EZH2 silencing resulted in decreased cell viability and invasiveness, and increased apoptosis. In addition, EZH2 silencing enhanced the cytotoxicity of taxanes and cisplatin in Hec-1A and Ishikawa endometrial cancer cells. EZH2 silencing using small-interfering RNA (siRNA) incorporated into chitosan nanoparticles (siRNA/CN) induced a significant anti-tumor effect compared with that observed in controls (66.6% reduction in Hec-1A cells and 63.2% reduction in Ishikawa cells, p < .05 for both). Moreover, EZH2 siRNA/CN in combination with taxanes produced more robust anti-tumor effects versus those induced by monotherapies (77.0% for Hec-1A cells and 57.7% for Ishikawa cells, p < .05 for both). These results were associated with decreased angiogenesis and cell proliferation, and enhanced apoptosis. Genomic analyses revealed that EZH2 silencing decreased the expression levels of many genes associated with tumor growth, including PRDX6. Collectively, these results support EZH2 as an attractive target for the therapeutic management of endometrial cancer.

Abstract P2-08-53: Tumor elasticity and clinicopathologic factors affecting neoadjuvant chemotherapy response in breast cancer patients

Background: Neoadjuvant chemotherapy for breast cancer has been increased. Many studies have reported on clinicopathologic factors to predict neoadjuvant chemotherapy response. Elastography, which is usually used to differentiate benign and malignant tumors, can be performed to evaluate tissue elasticity during conventional ultrasonography. The purpose of this study was to determine the clinicopathologic factors, including tumor elasticity, that affect neoadjuvant chemotherapy response in stage II or III breast cancer patients.

Methods: From April 2014 to March 2017, 95 patients received neoadjuvant chemotherapy for clinical stage IIa-IIIc primary breast cancer. To evaluate tumor elasticity, strain elastography was performed in 74 patients before neoadjuvant chemotherapy. Patients were divided into two groups by the Tsukuba elasticity scoring system (soft group ≤3 vs. hard group ≥4). Histologic type, nuclear grade, tumor infiltrating lymphocytes (TILs), tumor cellularity, characteristics of stroma, and hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status were evaluated using core needle biopsy specimens obtained before neoadjuvant chemotherapy. Pathologic complete response (pCR) was defined as the absence of invasive carcinoma in breast (ypT0 and ypTis) and axillary lymph node (ypN0). Residual cancer burden (RCB) was also calculated in 79 cases and the cases were categorized into 2 groups; favorable RCB group (RCB-0 and I) and unfavorable RCB group (RCB-II and III).

Results: The mean age of patients was 46.43±8.62 years (range, 27-71 years) and the mean initial tumor size was 3.63±1.95cm (range, 2.1-12.8cm). Twenty-four patients (32.4%) were categorized into the soft group and 50 patients (67.6%) into the hard group. The mean tumor cellularity on core needle biopsy specimens and characteristics of stroma were not significantly different between the two groups (p=0.35 and p=0.79, respectively). Twenty-two patients achieved pCR (23.2%). The patients with pCR were more likely to have estrogen receptor (ER) or progesterone receptor (PR) negative breast cancer (p=0.04 and p=0.03). The rate of nuclear grade 3 was higher in patients with pCR than those without (p=0.03). Tumor elasticity was not correlated with pCR (p=0.28). Thirty patients (38.0%) achieved favorable RCB and forty-nine patients (62.0%) had unfavorable RCB. Not only the rates of ER negativity (p=0.05), PR negativity (p=0.03), nuclear grade 3 (p=0.01), and high TILs level (≥ 10%) (p=0.04) but also the mean TILs level (p=0.05) were significantly higher in the favorable RCB group compared withthe unfavorable RCB group. No significant difference in tumor elasticity was observed between the two groups (p=0.30). In univariate analyses, nuclear grade 3 (p=0.03), and high TILs level (≥10%) (p=0.04) were significantly correlated with favorable RCB. HR negativity was an independent predictor of favorable RCB in multivariate analysis (odds ratio, 2.93; 95% confidence interval, 1.04-8.28; p=0.04).

Conclusion: Tumor elasticity was not associated with pCR or RCB. HR negativity was an independent predictor for favorable RCB.Nuclear grade and TILs were also potential predictive factors for neoadjuvant chemotherapy response.

Citation Format: Park JY, Choi JE, Bae YK, Lee SJ. Tumor elasticity and clinicopathologic factors affecting neoadjuvant chemotherapy response in breast cancer patients [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-08-53.

Abstract P3-03-02: Redo sentinel lymph node biopsy for ipsilateral breast tumor recurrence after breast conserving surgery with negative sentinel nodes: A pooled analysis from a systematic review and two institutes

Background:Cases of redo sentinel lymph node biopsy (SLNB) are growing according to the increase of ipsilateral breast tumor recurrence (IBTR) after breast-conservative surgery (BCS). To evaluate a feasibility of redo SLNB in patients with IBTR after negative SLN, we conveyed a pooled analysis using data from a systematic review and two institutes.

Materials and methods:A systematic search of PubMed was conducted to identify data of patient level from publications evaluating redo SLNB for cases with IBTR. Eligible patients who underwent BCS and were confirmed as negative axilla after SLNB were identified. An identification rate (IR) and a false-negative rate (FNR) were calculated. To identify FNR, we only included cases with back-up axillary node dissection (ALND) from retrieved data.

Results:In a systematic review, a total of 197 peer-reviewed publications were retrieved, of which 19 papers included patients who met eligibility criteria. Data from 464 patients were collected. In two-institutes, 38 cases with same criteria were identified. A total of 502 patient's data were pooled. The IR of redo-SLNB was 71.7% (360/502) in pooled data. For the FNR, data from 147 patients with back-up ALND after SLNB was analyzed. The FNR and accuracy of redo-SLNB were 9.8% (5/51) and 97% (142/147).

Conclusions:We found that the IR and the FNR of redo SLNB were 71.7% and 9.8%, respectively. Redo SLNB is reliable procedure for axillary staging in patients with IBTR after negative SLNB.

Citation Format: Yoon C-i, Bae SJ, Choi JE, Cha CH, Park SE, Ahn SG, Jeong J. Redo sentinel lymph node biopsy for ipsilateral breast tumor recurrence after breast conserving surgery with negative sentinel nodes: A pooled analysis from a systematic review and two institutes [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-03-02.

Liver-specific Gene Delivery Using Engineered Virus-Like Particles of Hepatitis E Virus

Virus-like particles (VLPs) possess great potential for organ-specific transport of therapeutic agents due to their central cavity surrounded by viral capsid proteins and similar tropism to their original viruses. The N-terminal truncated second open reading frame (Nt-ORF2) of the hepatotropic hepatitis E virus (HEV) forms VLPs via self-assembly. In the present study, we investigated whether HEV-LPs could deliver foreign genes specifically to the liver. HEV-LPs were obtained from Nt-ORF2 expression in Huh7 cells that were transduced with recombinant baculoviruses and purified by continuous density gradient centrifugation. The purified HEV-LPs efficiently penetrated liver-derived cell lines and the liver tissues. To evaluate HEV-LPs as gene delivery tools, we encapsulated foreign plasmids in HEV-LPs with disassembly/reassembly systems. Green fluorescence was detected at higher frequency in liver-derived Huh7 cells treated with HEV-LPs bearing GFP-encoding plasmids than in control cells. Additionally, HEV-LPs bearing Bax-encoding plasmids induced apoptotic signatures in Huh7 cells. In conclusion, HEV-LPs produced in mammalian cells can encapsulate foreign genes in their central cavity and specifically transport these genes to liver-derived cells, where they are expressed. The present study could contribute to advances in liver-targeted gene therapy.

CD9 Expression in Tumor Cells Is Associated with Poor Prognosis in Patients with Invasive Lobular Carcinoma

Purpose

We investigated the prognostic significance of CD9 expression in tumor cells of patients with invasive lobular carcinoma (ILC).

Methods

CD9 expression was evaluated by immunohistochemistry in 113 ILC tissue samples. Correlation of CD9 expression with the patients' clinicopathological parameters and overall survival was assessed.

Results

CD9 expression was detected in 48 (42.5%) ILC patients. However, no significant relation could be determined between CD9 expression and the clinicopathological parameters of the patient including tumor size, lymph node metastasis, lymphovascular invasion, histologic grade, expression of hormone receptors, human epidermal growth factor receptor 2 status, and Ki-67 labeling index. Patients with CD9 expression had worse overall survival (p = 0.051) and disease-free survival (DFS, p = 0.014) compared to patients without CD9 expression. Multivariate analysis revealed that CD9 expression was an independent prognostic factor for DFS (p = 0.049).

Conclusion

CD9 expression in tumor cells could be a significant prognostic marker in patients with ILC.

Intense upconversion red emission from Gd-doped NaErF4:Tm-based core/shell/shell nanocrystals under 980 and 800 nm near infrared light excitations

Strong upconversion red-emitting Gd-doped NaErF₄:Tm-based upconversion nanophosphors (UCNPs) are successfully synthesized by the formation of a core/intermediate shell/active shell structure.

Comparative Study between Sentinel Lymph Node Biopsy and Axillary Dissection in Patients with One or Two Lymph Node Metastases

Purpose

Sentinel lymph node biopsy (SLNB) is a standard axillary surgery in early breast cancer. If the SLNB result is positive, subsequent axillary lymph node dissection (ALND) is a routine procedure. In 2011, the American College of Surgeons Oncology Group Z0011 trial revealed that ALND may not be necessary in early breast cancer with one or two positive sentinel lymph nodes. The purpose of this study was to compare outcomes among Korean patients with one or two positive axillary lymph nodes in the final pathology who did and did not undergo ALND.

Methods

A total of 131,717 patients from the Korea Breast Cancer Society registry database received breast cancer surgery from January 1995 to December 2014. Inclusion criteria were T stage 1 or 2, one or two positive lymph nodes, and having received breast-conserving surgery (BCS), whole breast radiation therapy, and no neoadjuvant therapy. We analyzed the differences in disease-specific survival (DSS) and overall survival (OS) between patients who received SLNB only and those who underwent SLNB+ALND.

Results

A total 4,442 patients met the inclusion criteria, with 1,268 (28.6%) in the SLNB group and 3,174 (71.4%) in the SLNB+ALND group. There were no differences in DSS and OS between the two groups (p=0.378 and p=0.925, respectively). The number of patients who underwent SLNB alone for one or two positive lymph nodes increased continuously from 2004 to 2014.

Conclusion

Korean patients with early breast cancer and 1 or 2 positive axillary lymph nodes who received BCS plus SLNB showed no significant difference in DSS and OS regardless of whether they received ALND. The findings of this retrospective study demonstrate that omitting ALND can be considered when treating selected patients with early breast cancer who have one or two positive lymph nodes.

Interleukin-13 receptor alpha 2 expression in tumor cells is associated with reduced disease-free survival in patients with luminal subtype invasive breast cancer

Interleukin-13 receptor alpha 2 is one of the subunits of transmembrane receptor for interleukin-13. The aim of this study was to investigate the prognostic value of interleukin-13 receptor alpha 2 expression in invasive breast cancer. Interleukin-13 receptor alpha 2 expressions were assessed by immunohistochemistry in tissue microarrays of 1283 invasive breast cancer samples, and associations between these expressions and clinicopathological variables and clinical outcomes were investigated. Interleukin-13 receptor alpha 2 expression was observed in 138 (10.8%) samples, and found to be associated with positive estrogen receptor (p < 0.001) and progesterone receptor (p < 0.001) and with the luminal subtype (p < 0.001). No significant association was found between interleukin-13 receptor alpha 2 expression and other clinicopathological variables including age, tumor size, lymph node metastasis, histologic types, histologic grade, HER2 status, Ki-67 labeling index, or tumor-infiltrating lymphocytes levels. Patients with interleukin-13 receptor alpha 2 expression tended to have poorer disease-free survival, but the difference was not statistically significant (p = 0.069). Subgroup analysis showed luminal breast cancer patients positive for interleukin-13 receptor alpha 2 expression had significantly poorer disease-free survival (p = 0.018) than luminal breast cancer patients negative for interleukin-13 receptor alpha 2 expression. However, no association between interleukin-13 receptor alpha 2 expression and clinical outcome was observed in HER2-positive and triple-negative subgroups (p = 0.574 and p = 0.936, respectively). Multivariate analysis showed interleukin-13 receptor alpha 2 expression was an independent poor prognostic factor for luminal breast cancer (p = 0.03). This study shows interleukin-13 receptor alpha 2 expression could be a useful prognostic marker for selecting patients with luminal breast cancer likely to follow a clinically aggressive course despite receiving systemic therapy.

Differentiation between incomplete Kawasaki disease and secondary hemophagocytic lymphohistiocytosis following Kawasaki disease using N-terminal pro-brain natriuretic peptide

Purpose

Hemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory syndrome with many causes, including Kawasaki disease (KD). The purpose of this study was to identify the laboratory tests needed to easily differentiate KD with HLH from incomplete KD alone.

Methods

We performed a retrospective study on patients diagnosed with incomplete KD and incomplete KD with HLH (HLH-KD) between January 2012 and March 2015. We compared 8 secondary HLH patients who were first diagnosed with incomplete KD with all 247 incomplete KD diagnosed patients during the study period. The complete blood count, erythrocyte sedimentation rate, platelet count, and serum total protein, albumin, triglyceride, C-reactive protein, N-terminal pro-brain natriuretic peptide (NT-proBNP), and ferritin levels were compared. Clinical characteristics and echocardiography findings were also compared between the 2 groups.

Results

The total duration of fever was longer in the HLH-KD group than in the KD group. White blood cell and platelet counts were higher in the KD group. Alanine aminotransferase, ferritin, and coronary artery diameter were increased in the HLH-KD group compared with those in the KD group. The median of NT-proBNP was significantly higher in the HLH-KD group than in the KD group at 889.0 (interquartile range [IQR], 384.5-1792.0) pg/mL vs. 233.0 (IQR, 107.0-544.0) pg/mL.

Conclusion

The NT-proBNP level may be helpful in distinguishing incomplete KD from KD with HLH. The NT-proBNP level should be determined in KD patients with prolonged fever, in addition to the white blood cell count, platelet count, and ferritin level, to evaluate secondary HLH.

Once-daily dosing of amikacin for treatment of Mycobacterium abscessus lung disease

SETTING

Tertiary referral centre, Samsung Medical Center, South Korea.

OBJECTIVE

To evaluate the pharmacokinetic parameters and toxicities of once-daily amikacin (AMK) dosing for lung disease due to Mycobacterium abscessus.

DESIGN

A retrospective review of 48 patients with M. abscessus lung disease who received once-daily AMK for 4 weeks between January 2012 and June 2015.

RESULTS

With a starting dose of 15 mg/kg/day and adjustment of AMK dose according to the peak serum level (Cmax), the Cmax target of 55-65 μg/ml was achieved in 31.3% (15/48) of patients in the first week, 68.8% (33/48) in week 2, 91.7% (44/48) in week 3 and 95.8% (46/48) in week 4. Transient nephrotoxicity developed in 6.3% (3/48) of patients and ototoxicity in 25.0% (6/24), which was determined by audiogram as hearing loss, asymptomatic in five patients and tinnitus in one. Multivariate analysis revealed that the highest drug concentration 12 h after administration was significantly associated with the development of toxicities (adjusted odds ratio 1.862, P = 0.047).

CONCLUSION

Our results suggest that once-daily AMK for 4 weeks with a target Cmax of 55-65 μg/ml can be used in patients with M. abscessus lung disease, with careful monitoring of toxicity.

Abstract P5-22-03: Arm node preserving surgery in primary breast cancer patients : 5 year experience

Background:

Lymphedema is one of the major complications of axillary lymph node dissection (ALND) in patients with breast cancer. Axillary reverse mapping (ARM) is the technique to find lymphatic drainage from the arm during ALND. The purpose of this study is to evaluate the efficacy of arm node preserving surgery using ARM for reducing the incidence of lymphedema after axillary lymph node dissection in breast cancer patients and its oncologic safety.

Methods:

From January 2009 to October 2014, 167 patients with primary breast cancer were included. In all patients, 1 mCi of 99mTc-phytate was injected at the ipsilateral subareolar plexus and for axillary reverse mapping, 2.5mL of methylene blue was injected into the subcutaneous area of the medial intermuscular groove of the ipsilateral upper arm. The injection site was massaged for at least 5 minutes with the arm lifted above the heart level. At least 15 minutes later, ALND was performed and blue-stained arm nodes were identified. Arm nodes that were enlarged, hard or looked suspicious for metastasis were removed and all other arm nodes were preserved. Arm circumference at 10cm proximal to the medial epicondyle were measured pre- and post-operatively for 2 years. Circumference difference between both upper arms (CD) was evaluated and lymphedema was defined as CD of ≥ 2cm. Follow-up studies were performed every 6 months for 5 years and then annually using mammography, ultrasonography, and/or positron emission tomography.

Results:

Among 167 patients, 125 patients (74.9%) had their arm node preserved (ANP) and 42 (25.1%) patients had their arm node removed (ANR). Statistically significant difference in the mean number of harvested nodes was observed between ANP group (17.85±6.74) and ANR group (20.17±6.08) (p=0.05). The mean number of total identified blue stained arm nodes were 1.35±0.84. The mean follow-up period for measurement of arm circumference was 16.62±8.36 months. The last measured CD between both upper arms was 0.19±0.67cm in ANP group and 0.67±0.92cm in ANP group (p=0.003). 20 patients complained subjective symptoms of lymphedema, 7 patients in ANP group and 13 patients in ANR group (5.6% vs 31%, p&lt;0.001). Among them, one patient in ANP group and 6 patients in ANR group were diagnosed with lymphedema ( 0.8% vs 14.3%, p=0.001). The other 13 patients' CDs between both upper arms were below objective criteria of lymphedema. Follow-up studies were performed for 59.4±22.40 months. There were 16 cases of distant metastasis, 12 cases in ANP group, 4 cases in ANR group (9.6% vs 9.5%, p=1). Two patients in ANP group had distant metastasis and ipsilateral axillary recurrence simultaneously, but their TNM stages were already IIIc and IIb at the diagnosis. There's no solitary axillary recurrence.

Conclusion:

Arm node preserving surgery using axillary reverse mapping in breast cancer patients can reduce the incidence of lymphedema after axillary lymph node dissection and it simultaneously has oncologic safety.

Citation Format: Park JY, Choi JE, Bae YK, Lee SJ. Arm node preserving surgery in primary breast cancer patients : 5 year experience [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-22-03.

Role of ADAM17 in invasion and migration of CD133-expressing liver cancer stem cells after irradiation

We investigated the biological role of CD133-expressing liver cancer stem cells (CSCs) enriched after irradiation of Huh7 cells in cell invasion and migration. We also explored whether a disintegrin and metalloproteinase-17 (ADAM17) influences the metastatic potential of CSC-enriched hepatocellular carcinoma (HCC) cells after irradiation. A CD133-expressing Huh7 cell subpopulation showed greater resistance to sublethal irradiation and specifically enhanced cell invasion and migration capabilities. We also demonstrated that the radiation-induced MMP-2 and MMP-9 enzyme activities as well as the secretion of vascular endothelial growth factor were increased more predominantly in Huh7^CD133+ cell subpopulations than Huh7^CD133− cell subpopulations. Furthermore, we showed that silencing ADAM17 significantly inhibited the migration and invasiveness of enriched Huh7^CD133+ cells after irradiation; moreover, Notch signaling was significantly reduced in irradiated CD133-expressing liver CSCs following stable knockdown of the ADAM17 gene. In conclusion, our findings indicate that CD133-expressing liver CSCs have considerable metastatic capabilities after irradiation of HCC cells, and their metastatic capabilities might be maintained by ADAM17. Therefore, suppression of ADAM17 shows promise for improving the efficiency of current radiotherapies and reducing the metastatic potential of liver CSCs during HCC treatment.

Role of ADAM17 in invasion and migration of CD133-expressing liver cancer stem cells after irradiation

We investigated the biological role of CD133-expressing liver cancer stem cells (CSCs) enriched after irradiation of Huh7 cells in cell invasion and migration. We also explored whether a disintegrin and metalloproteinase-17 (ADAM17) influences the metastatic potential of CSC-enriched hepatocellular carcinoma (HCC) cells after irradiation. A CD133-expressing Huh7 cell subpopulation showed greater resistance to sublethal irradiation and specifically enhanced cell invasion and migration capabilities. We also demonstrated that the radiation-induced MMP-2 and MMP-9 enzyme activities as well as the secretion of vascular endothelial growth factor were increased more predominantly in Huh7CD133+ cell subpopulations than Huh7CD133- cell subpopulations. Furthermore, we showed that silencing ADAM17 significantly inhibited the migration and invasiveness of enriched Huh7CD133+ cells after irradiation; moreover, Notch signaling was significantly reduced in irradiated CD133-expressing liver CSCs following stable knockdown of the ADAM17 gene. In conclusion, our findings indicate that CD133-expressing liver CSCs have considerable metastatic capabilities after irradiation of HCC cells, and their metastatic capabilities might be maintained by ADAM17. Therefore, suppression of ADAM17 shows promise for improving the efficiency of current radiotherapies and reducing the metastatic potential of liver CSCs during HCC treatment.

C-reactive protein and N-terminal pro-brain natriuretic peptide discrepancy: a differentiation of adenoviral pharyngoconjunctival fever from Kawasaki disease

Purpose

To differentiate adenoviral pharyngoconjunctival fever (PCF) from acute Kawasaki disease (KD) using laboratory tests before results of virus-real time polymerase chain reaction and ophthalmologic examination are obtained.

Methods

Baseline patient characteristics and laboratory measurements were compared between 40 patients with adenovirus infection and 123 patients with KD.

Results

The patients with adenovirus infection were generally older than those with KD (median: 3.9 years vs. 2 years, P=0.000). White blood cell and, platelet count, and aspartate aminotransferase, alanine aminotransferase, and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels showed significant differences between the 2 groups, but the C-reactive protein (CRP) levels did not (6.8±3.0 mg/dL vs. 8.3±5.8 mg/dL, P=0.126). In the adenovirus infection group, the CRP levels were <1, <3, <10, and ≥10 mg/dL in 2 (5%), 3 (7.5%), 30 (75%), and 5 patients (12.5%), respectively. The cutoff NT-proBNP level was 265 pg/mL. Discrepancy was defined as CRP and NT-proBNP levels of ≥3 or <3 mg/dL, and <265 or ≥265 pg/mL, respectively. Among the 35 patients with adenovirus infection whose CRP levels were ≥3 mg/dL, 29 (82.9%) showed a discrepancy. Conversely, of the 103 patients with KD whose CRP levels were ≥3 mg/dL, 83 (80.6%) showed no discrepancy. Between the groups, a significant difference in discrepancy rate was observed (P=0.000). None of the patients with adenovirus infection had CRP and NT-proBNP levels of <3 mg/dL and ≥265 pg/mL, respectively.

Conclusion

With a sensitivity of 82.9% and a specificity of 80.6%, CRP and NT-proBNP levels may differentiate between adenoviral PCF and acute KD.

Elk-3 Contributes to the Progression of Liver Fibrosis by Regulating the Epithelial-Mesenchymal Transition

Background/Aims

The role of Elk-3 in the epithelial-mesenchymal transition (EMT) during liver fibrogenesis remains unclear. Here, we determined the expression of Elk-3 in in vitro and in vivo models and in human liver fibrotic tissues. We also investigated the molecular relationships among Elk-3, early growth response-1 (Egr-1), and the mitogen activated protein kinases (MAPK) pathway during EMT in hepatocytes.

Methods

We established anin vitro EMT model in which normal mouse hepatocyte cell lines were treated with transforming growth factor (TGF)-β1 and a CCl₄-induced liver fibrosis model. Characteristics of EMT were determined by evaluating the expression levels of related markers. The expression of Elk-3 and its target Egr-1 were analyzed using Western blotting. Gene silencing of Elk-3 was performed using an siRNA knockdown system.

Results

The expression levels of mesenchymal markers were increased during TGF-β1-induced EMT of hepatocytes. The expression levels of Elk-3 and Egr-1 were significantly (p<0.05) increased during the EMT of hepatocytes, in CCl₄-induced mouse liver fibrotic tissues, and in human liver cirrhotic tissues. Silencing of Elk-3 and inhibition of the Ras-Elk-3 pathway with an inhibitor suppressed the expression of EMT-related markers. Moreover, Elk-3 expression was regulated by p38 MAPK phosphorylation during EMT.

Conclusions

Elk-3 contributes to the progression of liver fibrosis by modulating the EMT via the regulation of Egr-1 under MAPK signaling.

RAR-Related Orphan Receptor Gamma (ROR-γ) Mediates Epithelial-Mesenchymal Transition Of Hepatocytes During Hepatic Fibrosis

The epithelial‐mesenchymal transition (EMT) is involved in many different types of cellular behavior, including liver fibrosis. In this report, we studied a novel function of RAR‐related orphan receptor gamma (ROR‐γ) in hepatocyte EMT during liver fibrosis. To induce EMT in vitro, primary hepatocytes and FL83B cells were treated with TGF‐β1. Expression of ROR‐γ was analyzed by Western blot in the fibrotic mouse livers and human livers with cirrhosis. To verify the role of ROR‐γ in hepatocyte EMT, we silenced ROR‐γ in FL83B cells using a lentiviral short hairpin RNA (shRNA) vector. The therapeutic effect of ROR‐γ silencing was investigated in a mouse model of TAA‐induced fibrosis by hydrodynamic injection of plasmids. ROR‐γ expression was elevated in hepatocyte cells treated with TGF‐β1, and ROR‐γ protein levels were elevated in the fibrotic mouse livers and human livers with cirrhosis. Knockdown of ROR‐γ resulted in the attenuation of TGF‐β1‐induced EMT in hepatocytes. Strikingly, ROR‐γ bound to ROR‐specific DNA response elements (ROREs) in the promoter region of TGF‐β type I receptor (Tgfbr1) and Smad2, resulting in the downregulation of Tgfbr1 and Smad2 after silencing of ROR‐γ. Therapeutic delivery of shRNA against ROR‐γ attenuated hepatocyte EMT and ameliorated liver fibrosis in a mouse model of TAA‐induced liver fibrosis. Overall, our results suggest that ROR‐γ regulates TGF‐β‐induced EMT in hepatocytes during liver fibrosis. We suggest that ROR‐γ may become a potential therapeutic target in treating liver fibrosis. J. Cell. Biochem. 118: 2026–2036, 2017. © 2016 The Authors. Journal of Cellular Biochemistry Published by Wiley Periodicals Inc.

Conversion from weight to volume of mastectomy specimen: Convenient equations

Accurate restoration of the volume lost during breast removal is the key to achieve beautiful, symmetric breasts. This study aimed to devise a simpler and more accurate method for measuring breast tissue volume by studying the relationship between weight and volume of the excised tissue according to density. Mammograms of 276 women who were advised to undergo breast reconstruction surgery were divided into 4 different groups according to tissue densities. The correlation between weight and volume was studied for each group. The regression equations are as follows: 1st group: V = 1.218 × W+7.45 (V: volume, W: weight). 2nd group: V = 1.036 × W + 10.36. 3rd group: V = 0.969 × W-7.47. 4th group: V = 0.871 × W-14.13. These equations will be useful for reconstruction of natural-appearing and symmetric breasts following mastectomy.

Prognostic significance of CD9 expression differs between tumour cells and stromal immune cells, and depends on the molecular subtype of the invasive breast carcinoma

AIMS

CD9, a tetraspanin transmembrane protein, modulates cell motility, migration, and proliferation. The aim of this study was to investigate the prognostic significance of CD9 expression in patients with invasive breast carcinoma (IBC).

METHODS AND RESULTS

CD9 expression was evaluated in tissue microarrays of 1349 IBC samples via immunohistochemistry. CD9 expression in tumour cells (T-CD9 expression) and CD9 expression in stromal immune cells (S-CD9 expression) were analysed separately. T-CD9 expression was observed in 732 (54.3%) cases, and was associated with lymph node metastasis, histological type, lymphovascular invasion, high histological grade, HER2 positivity, a high Ki67 labelling index, and distant metastasis. S-CD9 expression was observed in 833 (61.7%) cases, and was associated with large tumour size, histological type, high histological grade, negative hormone receptors, HER2 positivity, a high Ki67 labelling index, and tumour-infiltrating lymphocytes. Patients with T-CD9 expression had shorter disease-free survival (DFS) than those without T-CD9 expression in the univariate and multivariate analyses. However, S-CD9 expression correlated significantly with a favourable DFS in the univariate and multivariate analyses. In the subgroup analysis, T-CD9 expression and S-CD9 expression were independent markers for DFS in luminal A and luminal B (HER2-negative) subgroups, respectively.

CONCLUSIONS

T-CD9 expression could be a biomarker for poor prognosis in luminal A IBC, whereas S-CD9 expression could be a marker of good prognosis in luminal B (HER2-negative) IBC. Therefore, tumour compartment-specific analyses considering molecular subtypes are necessary to study the prognostic significance of CD9 expression in IBC.