Abstract P2-07-09: Immune recurrence score (IRS) using 7 immunoregulatory protein expression can predict recurrence in stage I-III breast cancer patients

Background: Immune cells in the tumor microenvironment play an essential role in tumor progression and regression. However, immunologic characteristics and their prognostic role have not been clearly identified in breast cancer patients. This study aimed to evaluate the immunologic characteristics and their prognostic role in breast cancer patients.

Methods: This study enrolled pathologically proven stage I-III breast cancer patients. We performed immunohistochemical staining in stromal tumor-infiltrating lymphocytes (TILs) using 10 immune markers (PD-1, PD-L1, PD-L2, IDO, TIM3, OX40, OX40L, B7-H2, B7-H3, B7-H4) with known/possible clinical relevance. Expression of PD-1, PD-L1, and PD-L2 was also measured in adjacent tumor tissue. Intensity and proportion of the staining was measured for each immune marker. The intensity of immunohistochemical staining (IS, intensity score) was graded as follows: 0 (negative), 1 (weak), 2 (moderate), 3 (strong). The proportion of staining (PS, proportion score) was graded as follows: 0 (stain under <1%), 1 (1% to 5%), 2 (5% to 10%), 3 (10 to 25%), 4 (25% to 50%), Grade 5 (> 50%). Immune markers were defined as positive with one of the following; IS 1 with PS over 3, IS 2 with PS over 2, IS 3 with PS over 1.

Results: A total of 392 patients, 271 (69.1%) luminal A, 36 (9.2%) luminal B, 32 (8.2%) HER2-positive, and 53 (13.5%) triple negative breast cancers were included. In total, PD-1 was expressed by stromal TILs in 130 (33.2%) patients, PD-L1 in 47 (12.0%), PD-L2 in 109 (27.8%), B7-H2 in 225 (57.4%), B7-H3 in 227 (57.9%), B7-H4 in 106 (27.0%), TIM3 in 111 (28.3%), IDO in 96 (24.5%), OX40 in 137 (34.9%), and OX40L in 165 (42.1%). In addition, PD-L1 was expressed in 15 (3.8%) tumor tissue, PD-L2 in 237 (60.5%), and PD-1 was not expressed in tumor tissue. Each breast cancer subtype showed different immunologic characteristics. Expression of PD-1 (stromal TILs) and PD-L1 (Tumor and stromal TILS) was higher in HER2-positive and triple negative breast cancer. By contrast, expression of TIM-3, OX40, and OX40L by stromal TILs were higher in luminal A and luminal B breast cancer. In the univariate analysis, expression of B7-H3 was associated with worse DFS and expression of OX40 and B7-H4 was associated with favorable DFS. Expression of PD-L1, PD-L2, OX40L, and B7-H2 had a tendency of favorable DFS. We devised an immune recurrence score (IRS) using 7 markers with prognostic value (B7-H2, B7-H3, B7-H4, OX40, OX40L, PD-L1, and PD-L2). Patients were classified as high-risk (31 patients, 7.9%), intermediate-risk (265, 67.6%), or low-risk (96, 24.5%) according to 7 immune marker expression. In the multivariate analysis, IRS low-risk (adjusted HR, 0.14; 95% CI, 0.04 – 0.45; p = 0.001) and intermediate-risk (adjusted HR, 0.32; 95% CI, 0.16 - 0.656.42; p = 0.002) had significantly lower risk of recurrence compared with high-risk. In the subgroup analysis, the prognostic role of IRS were maintained in both luminal A patients and non-luminal A patients.

Conclusions: This study identified immunologic characteristics of breast cancer patients using 10 immune markers. In addition, we devised an IRS with 7 immune markers which may predict recurrence in stage I-III breast cancer patients.

Citation Format: Lee D-W, Ryu HS, Lee K-H, Jin M-S, Woo G-U, Suh KJ, Yang Y, Kim H-J, Lee H-B, Kim T-Y, Moon H-G, Han W, Park IA, Noh D-Y, Im S-A. Immune recurrence score (IRS) using 7 immunoregulatory protein expression can predict recurrence in stage I-III 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 P2-07-09.

Abstract P4-14-09: A nationwide data on the cardiovascular protective effect of tamoxifen and aromatase inhibitor in postmenopausal women with breast cancer

A large proportion of breast cancer patients receive hormonal therapy as their adjuvant treatment options. For postmenopausal women, the initial choice for the hormonal therapy is aromatase inhibitor (AI), and tamoxifen (TM) is reserved for women experiencing severe side effects against AI or having low bone density. An important but unresolved clinical question regarding the use of AI in postmenopausal women is the safety of AI regarding the risk cardiovascular events. Studies have shown inconsistent results over the cardiovascular safety of AI and TM. In this study, we investigated the risk of developing cardiovascular and cerebrovascular events in women with breast cancer who receive hormonal therapy using AI, TM, or both.

To this end, we used the National Health Insurance Sharing Service in Korea which is provided by National Health Insurance Service. The database provides anonymized insurance data for research purposes after the approval of the review committee. In the database, we identified 47,569 women with the age older than 55 who were diagnosed with breast cancer. Patients were classified as no hormonal treatment group (n=18,807), AI group (n=19,584), TM group (n=7,081), or Switch group (n=2,097). The Switch group was defined as the women with history of both AI and TM prescriptions. During the studied period, a total of 2,032 cardiovascular or cerebrovascular events (CVE) were recorded.

Overall, the women prescribed with TM had significantly less hazard ratio for developing CVE when compared to the women who did not receive any hormonal treatment (HR 0.809 95% C.I. 0.706-0.928). However, this protective effect of tamoxifen was not observed in either AI or Switch group (HR 0.917 95% C.I. 0.833-1.010, and HR 0.856 95% C.I. 0.695-1.053, respectively). The protective effect of TM was also similar in women older than 60 (HR 0.808 95% C.I. 0.696-0.938). The cardiovascular and cerebrovascular protective effects of tamoxifen was also substantial in high risk women defined by their family history of cardiovascular diseases and the diagnosis of hypertension or diabetes.

Our results suggest that the use of TM is associated with a substantial protective effect against developing cardiovascular or cerebrovascular events in women with breast cancer. However, the protective effect was not observed for women receiving AI. Our data suggest the potential tailored approach in hormonal treatment in breast cancer patients who are at high risk of cardiovascular of cerebrovascular events.

Citation Format: Moon H-G, Choi SH, Park Y, Jung JG, Ju YW, Kim KE, Kim Y, Lee E, Lee H-B, Han W, Noh D-Y, Yoon H-J. A nationwide data on the cardiovascular protective effect of tamoxifen and aromatase inhibitor in postmenopausal women with breast cancer [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 P4-14-09.

Associations between serum S100A8/S100A9 and knee symptoms, joint structures and cartilage enzymes in patients with knee osteoarthritis

OBJECTIVE

Animal studies suggest that S100A8/S100A9 may be involved in the pathogenesis of osteoarthritis (OA); however, there has been no clinical study examining the associations between serum S100A8/S100A9 and knee symptoms, joint structures and cartilage degradation enzymes in knee OA patients so far. Therefore, this study was designed to investigate the cross-sectional associations between serum levels of S100A8/S100A9 and the outcomes in patients with knee OA.

DESIGN

A total of 141 subjects with clinical knee OA were included. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score was used to assess joint symptoms. Magnetic resonance imaging (MRI) was used to measure knee structural abnormalities including cartilage defects. Knee radiography was used to assess joint space narrowing (JSN), osteophytes and the radiographic severity of OA. Enzyme-linked immunosorbent assay (ELISA) was used to measure the serum levels of S100A8/S100A9, matrix metalloproteinase (MMP)-3, MMP10 and MMP13.

RESULTS

In multivariable analyses, serum S100A8/S100A9 were positively associated with total WOMAC score (β: 0.111 per 10 ng/ml, P = 0.021), WOMAC weight-bearing pain (β: 0.015 per 10 ng/ml, P = 0.043) and WOMAC physical dysfunction (β: 0.091 per 10 ng/ml, P = 0.010), and had positive associations with total cartilage defects and cartilage defects at lateral femoral, lateral tibial and medial femoral sites (ORs: 1.006-1.008 per 10 ng/ml, all P < 0.05) and serum levels of MMP3 (β: 0.002 per 10 ng/ml, P = 0.032) in patients with clinical knee OA.

CONCLUSIONS

Serum levels of S100A8/S100A9 were positively associated with increased knee symptoms, cartilage defects and serum cartilage degradation enzymes in patients with knee OA, suggesting that S100A8/S100A9 may have a role to play in knee OA. Future longitudinal studies are required to confirm these findings.

A novel method for assessing proximal tibiofibular joint on MR images in patients with knee osteoarthritis

OBJECTIVES

To validate a method to measure the morphological parameters of the proximal tibiofibular joint (PTFJ) in patients with knee osteoarthritis (OA).

METHODS

408 participants were examined in this cross-sectional subject-based study. We calculated the fibular contacting area of PTFJ (S) and its projection areas onto the horizontal plane (load-bearing area, Sτ), the sagittal plane (lateral stress-bolstering area, Sφ) and the coronal plane (posterior stress-bolstering area, Sυ). Joint space narrowing (JSN) and osteophyte was measured using radiographs. Cartilage defects, bone marrow lesions (BMLs) and cartilage volume were evaluated using magnetic resonance imaging (MRI).

RESULTS

The average PTFJ fibular contacting area was 2.4 cm² (SD, ±0.7 cm²). Intra-observer and inter-observer reliabilities of measures of PTFJ morphological parameters were excellent (≥0.90). S, Sτ and Sφ were significantly associated with JSN in the medial tibiofemoral compartment (PR: 1.40, 95% CI 1.10-1.78; PR: 1.65, 95% CI 1.25-2.18 and PR: 0.53, 95% CI 0.29-0.97, respectively). There was a significantly positive association between S, Sτ and medial and/or femoral tibial cartilage defects. S, Sτ and Sυ were significantly and positively associated with medial and/or femoral tibial BMLs (PR: 1.36, 95% CI 1.12-1.64; PR: 1.47, 95% CI 1.17-1.83; and PR: 1.39, 95% CI 1.06-1.82, respectively) after adjustment. S and Sτ were significantly and negatively associated with medial tibial cartilage volume.

CONCLUSIONS

This novel method to assess the morphological parameters of PTFJ in MRI is reproducible. These parameters are associated with knee radiographic and MRI-based OA-related structural abnormalities, suggesting clinical construct validity. Its predictive validity needs to be examined in future longitudinal studies.

Alexithymia in Breast Cancer Patients and Their Sisters in Seoul

Background: The incidence of breast cancer has more than doubled in South Korea since 1999. Breast cancer in the family affects other members such as first degree relatives. Alexithymia is a psychological construct related to an inability to express ones feelings and has been found to be useful in identifying individuals who might benefit from targeted counseling to address distress. Aim: The purpose of this study was to examine the levels of alexithymia in breast cancer patients, their sisters and healthy controls in South Korea with the aim of identifying individuals who will benefit from targeted counseling. Methods: The Korean version of the alexithymia questionnaire was used to compare the groups. The study group consisted of 98 breast cancer in-patients, out-patients, follow-up cases and lymphedema clinic attendees undergoing treatment at the Breast Care Center, Seoul National University Cancer Hospital, 50 sisters and 43 healthy controls. Results: The highest level of alexithymia was reported in patients, followed by their siblings. Healthy controls reported the lowest level of alexithymia. Difficulty in describing feeling scores has shown significant negative correlation with age and marital status among women with breast cancer. Women 51 years and above and married women have lower scores than those below 50 years aged women and those who are single, in a live-in relationship, widowed or divorced. No such significant correlation was observed among siblings and control group. The intensity of cancer was a significant predictor of the alexithymia score. Patients with T4 stage disease reported the highest levels of alexithymia. No significant differences were found among patients with lower staging. Conclusion: Not only breast cancer patients, but also their sisters show significantly more alexithymia than their healthy counterparts. Counselors can use the alexithymia questionnaire to identify persons who require support to prevent or reduce psychological problems in patients and siblings.

Associations between knee structural measures, circulating inflammatory factors and MMP13 in patients with knee osteoarthritis

OBJECTIVE

To investigate cross-sectional associations between serum level of Matrix metalloproteinase (MMP)13 and knee structural measures and circulating inflammatory factors in patients with symptomatic knee osteoarthritis (OA).

DESIGN

A total of 149 subjects with symptomatic knee OA were included. Magnetic resonance imaging was used to measure infrapatellar fat pad (IPFP) volume, IPFP signal intensity alternation, cartilage volume and cartilage defects. Knee radiography was used to assess radiographic OA using the Kellgren-Lawrence (K-L) grading system. Enzyme-linked immunosorbent assay was used to measure the serum levels of inflammatory factors and MMP13.

RESULTS

In multivariable analyses, serum MMP13 was negatively associated with cartilage volume at patellar site (β: -32.94 mm³ per 10 ng/ml, P < 0.05), and positively associated with cartilage defect at medial femoral site (OR: 1.13 per 10 ng/ml, P < 0.05). Also, MMP13 was positively associated with K-L grading and IPFP signal intensity alteration (OR: 1.14 and 1.15 per 10 ng/ml, respectively, both P < 0.05), and negatively associated with IPFP volume (β: -0.34 cm³ per 10 ng/ml, P < 0.05). Furthermore, serum level of adiponectin was negatively associated serum MMP13 quartiles (OR: 0.66 per 10 μg/ml, P < 0.05), and serum levels of tumor necrosis factor (TNF)-α, interleukin (IL)-8 and IL-18 were positively associated with serum MMP13 quartiles (ORs: 1.01-1.18 per 10 pg/ml, all P < 0.05).

CONCLUSIONS

Serum level of MMP13 was associated with knee structural abnormalities as well as serum inflammatory factors. These suggest that systemic MMP13 may play a role in knee OA, and could be regulated by inflammatory factors.

Gender Differences in the Hepatotoxicity and Toxicokinetics of Emodin: The Potential Mechanisms Mediated by UGT2B7 and MRP2

Emodin is a main anthraquinone compound which exists in Chinese traditional medicines including Polygonum multiflorum and Rhubarb. It is documented to have obvious liver and kidney toxicity. This study aims to (a) estimate gender differences of the hepatotoxicity and toxicokinetics in rats after oral administration of emodin (60 and 150 mg/kg/d) for a consecutive 28 days and (b) clarify relative mechanisms caused by glucuronidation and disposition. Hepatotoxicity was significantly higher in female rats than that in male rats, as evidenced by histopathological and biochemical tests. Similarly, the toxicokinetic profiles of emodin have time and gender differences, which could cause time and gender differences in hepatotoxicity. The metabolic and transcriptomics data of 55 human liver and 36 human kidney samples demonstrated that UDP-glucuronosyltransferase 2B7 (UGT2B7) was the predominant enzyme for emodin glucuronidation. A genome-wide association study (GWAS) identified that rs11726899 located within ∼50 kb of the transcript of UGT2B could significantly affect emodin metabolism. Knockdown of UGT2B7 in HepG2 cells significantly decreased emodin glucuronidation and increased cytotoxicity of emodin. The gene expression and protein levels of UGT2B7 were decreased, but those of the multidrug-resistant-protein 2 (MRP2) were increased in HepG2 cells after being treated with 50 μM emodin for 48 h. Long-term use of emodin could decrease the intrinsic clearance (CL_int, decreased by 18.5%-35.4%) values of zidovidue (UGT2B7 substrate) glucuronide in both male and female liver microsomes from rats administrated with emodin for 28 days, thus causing the accumulation of emodin. However, higher self-induced MRP2 expression and lower hepatotoxicity were observed in emodin-treated male rats compared to that in female rats. Therefore, gender differences in the hepatotoxicity and toxicokinetics of emodin are potentially mediated by the coupling of UGT2B7 and MRP2 in vivo.

Systemic and local adipose tissue in knee osteoarthritis

Knee osteoarthritis (OA) is the most common joint disease. Body adipose tissue has been shown to be related to the development and progression of knee OA. Among systemic adipose tissues, subcutaneous adipose tissue is significantly and negatively associated with muscle mass and forces, and could be related to the presence and progression of knee OA. Visceral adipose tissue is associated with increased cartilage loss and production of pro-inflammatory cytokines. Intra-muscular adipose tissue is associated with knee osteoarthritic changes, but it remains controversial if inter-muscular adipose tissue has a role to play in the pathogenesis for knee OA. Knee local adipose tissue such as infrapatellar fat pad (IPFP) can interact with neighbouring tissues, and may have a biphasic effect in knee OA. The underlying mechanisms for the roles of the systemic and local fat in knee OA could be related to biomechanical, metabolic, inflammatory factors and fat fibrosis, which may have a separated or combined effect on OA. Tissue engineering from systemic or local adipose tissue is a new research direction, and adipose tissue-derived stem cells from systemic or local adipose tissue may be beneficial for OA cartilage repair. Research on systemic and local adipose tissue would provide novel approaches for prevention and treatment of knee OA, but further studies are required to explore the roles of different adipose tissues in knee OA and the effects of stem cells derived from different adipose tissues on knee OA.

Production and Characterization of a Tumor-Specific Monoclonal Antibody Act19 Recognizing an Epitope Distinctive from Sialosyl-Tn on the TAG72 Antigen

Aims

A murine monoclonal antibody ACT19 directed at the TAG72 tumor-associated antigen, which was originally defined by the B72.3 antibody, was established.

Methods

This was done by immunizing mice with the bovine mucin followed by the selection of hybridomas secreting antibodies with the desired specificity. In order to better characterize this antibody, its immunoreactivity was compared to that of the B72.3 antibody.

Results

The data showed that the ACT19 antibody bound specifically to the TAG72 antigen as the B72.3 antibody did. However, there were some differences between ACT19 and B72.3. Firstly, the immunoreactivity of ACT19 for the bovine mucin was lower than that of B72.3. Secondly, the immunoreactivity of ACT19 for the TAG72 antigen was not inhibited by N-acetylgalactosamine, nor was that of B72.3. Thirdly, ACT19 did not compete the binding reactivity of B72.3 for the TAG72 antigen. This suggests that the epitope defined by ACT19 is different from the sialosyl-Tn epitope recognized by B72.3. Immunoperoxidase staining of various tumors, normal and embryonic tissues for ACT19 was carried out. For the various tumors, only adenocarcinomas from the colon and stomach showed remarkable positivity. All the normal tissues were negative, except for weak positivity involving the zona reticularis of the adrenal cortex, and intestinal goblet cells. Embryonic tissues showed a wide spectrum of positivity with staining of the small and large intestine, stomach and renal tubules.

Conclusions

The ACT19 antibody appears to be a useful marker for colon and stomach cancers, and this additional anti-TAG72 antibody may be useful in conjunction with the B72.3 antibody in pathology and clinical application.

Tisagenlecleucel, an approved anti-CD19 chimeric antigen receptor T-cell therapy for the treatment of leukemia

On August 30, 2017, the U.S. Food and Drug Administration (FDA) approved Novartis' tisagenlecleucel (CTL-019, Kymriah), which is a synthetic bioimmune product of anti-CD19 chimeric antigen receptor (CAR) T cells, for the treatment of relapsed/refractory B-cell acute lymphoblastic leukemia (B-ALL). This was a milestone in tumor immunology on account of the significant antitumor effect of tisagenlecleucel for the treatment of relapsed/refractory B-ALL patients. Conventional standard therapies for B-ALL have high failure rates, thus developing new therapies is crucial for patients with B-ALL. Results from clinical trials indicate that anti-CD19 CAR T-cell therapies could successfully induce high response rates in B-ALL patients. However, related toxicities, such as cytokine release syndrome and CAR T-cell-related encephalopathy syndrome, may be severe or even fatal, and the management of such toxicities is therefore vital. This review will focus on the clinical application of anti-CD19 CAR T-cell therapy in B-ALL treatment, including design features of CAR constructs, therapeutic use of tisagenlecleucel, CAR T-cell therapy clinical trials and related toxicity, and prospects for cancer immunotherapy.

Abstract P4-06-18: Clinical application of multigene panel testing and genetic counseling for hereditary/familial breast cancer risk assessment: Prospective single center study

Background

The identification of individuals at elevated risk for hereditary cancers has allowed the development of consensus recommendations for cancer screening and prevention. The introduction of multigene panels may identify more individuals with breast cancer gene mutations than does testing for BRCA1/2 alone. Therefore, the multigenerational panel increase the need for genetic counseling suggesting preventive approach or cancer-specific screening to patients and family members. The rapid clinical introduction of multigene panel testing, however, have several issues such as low- to moderate-risk gene mutations and clinical recommendations. We collect the mutation results and clinical recommendations after testing with multigene panel and giving genetic counseling.

Methods

We had developed multigene panel consisted of 64 genes related to hereditary cancer through previous study and prospectively enrolled 104 individuals who were appropriate candidates for hereditary breast cancer evaluation. The patients were tested with 64-gene panel(Celemics) and results were provided by us 4˜10 weeks later. We checked the family history of cancer and made a pedigree before testing.

Result

Among 104 participants, 26 patients harbored deleterious mutations, most commonly in high to moderate-risk breast/ovarian cancer genes (BRCA1/2, BRIP, RAD51 and RAD51D), Lynch syndrome gene(MSH6) and other genes(FH, SPINK1). We recommended the cancer-specific screening and/or preventive approach for mutation-positive patients and suggested additional genetic test for the family members. Among them, 6 (23%) patients received Risk reducing procedures (Prophylactic mastectomy or oophorectomy) and most of them(19 patients(73%)) received cancer specific screening.

Conclusion

We demonstrate the use of multigene panel testing for hereditary breast cancer and will suggest the process of the genetic counseling including indication and results analysis with multigene panel testing.

Citation Format: Lee E-S, Han W, Kim Y, Rhu J, Park JH, Kim K-E, Ju YW, Kim R, Lee H-B, Moon H-G, Noh D-Y. Clinical application of multigene panel testing and genetic counseling for hereditary/familial breast cancer risk assessment: Prospective single center study [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 P4-06-18.

Abstract P4-06-16: Frequency of pathogenic mutation in patients at high risk for hereditary breast cancer

Background: Next-generation sequencing technology allows the simultaneous sequencing of multiple target genes. We developed a gene panel containing 64 genes which were associated with various hereditary cancers. This study was performed to evaluate the frequency of pathogenic mutations associated with hereditary cancer among Korean patients at high risk hereditary breast cancer using multi-gene sequencing panel.

Methods: A total of 252 breast cancer patients with high-risk hereditary cancer were included. Among them, 179 patients (71.0%) had multiple primary cancers including breast cancer, 27 patients (10.7%) were diagnosed with bilateral breast cancer at age 40 or younger. Thirty-five patients (13.9%) had breast cancer family history of more than 2 relatives. With the 64-gene panel, sequence variants were detected by next-generation sequencing technology.

Results: Sixty seven patients (26.8%) were found to have 77 germline pathogenic mutations, 12 in BRCA1, 13 in BRCA2, 9 in CDH1, 3 in FH, 5 in MSH2, 2 in MSH6, 4 in NAT1, 6 in PTCH1, 3 in RAD51, 7 in RET, 4 in SPINK1, 3 in TP53 and one each in ALK, BRIP1, CHEK2, MLH2, MUTYH, and PTEN. In 20 patients (4.0%), 2 (n=9) or 3 (n=1) pathogenic mutations were detected. In 227 patients with BRCA1/2 negative, CDH1 (n=7), RET (n=7), PTCH1 (n=5), and MSH2 (n=5) were the most prevalent pathogenic mutations.

Conclusions: The 64 gene panel detected germline pathogenic mutations in 26.8% of Korean breast cancer patients with feature of hereditary cancer. Mutations of BRCA1, BRCA2, CDH1, RET, and PTCH1 were the most prevalent variants.Mutation carriers were considered as high risk to develop malignancy and recommended to receive genetic counseling and intensive cancer screening.

Citation Format: Shin H-C, Yoo T-K, Lee H-B, Moon H-G, Noh D-Y, Han W. Frequency of pathogenic mutation in patients at high risk for hereditary breast cancer [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 P4-06-16.

Abstract P2-06-01: Molecular characterization of human malignant phyllodes tumors reveals potential targeted approaches

Malignant phyllodes tumor (MPT) which belong to the fibroepithelial neoplasm spectrum is a rare type of breast malignancy, and currently there is no effective targeted approach available for MPT. In this study, we tried to identify key genomic alterations and biologic pathways in MPT by whole exome and RNA sequencing of nine MPT tissues. Whole exome sequencing revealed somatic alterations in EGFR, MED12, PIK3CA, PIK3R1, PDGFRA, PDGFRB, PTEN, and TP53. Transcriptome sequencing showed dysregulation of ECM-receptor interaction, focal adhesion, and PI3K-Akt signaling in MPTs when compared to normal breast or invasive breast cancer tissues. Based on the transcriptome profiles, the MPTs were classified into two subtypes; fibrous subtype with upregulation of stromal genes such as collagens and epithelial subtype with upregulation of E-cadherin and Claudins. The molecular classification of fibrous and epithelial subtypes was validated in 28 paraffin-embedded MPT tissues. The fibrous subtype showed higher mitotic index and increased risk for recurrence when compared to the epithelial subtype. We established a patient-derived xenograft model from one fibrous subtype MPT which harbored somatic mutation in PIK3R1 and PDGFRB. In that model, targeted treatment against PIK3CA/mTOR and PDGFR pathways effectively suppressed the tumor growth in vivo. Our data provide insights on the biologic understanding of MPT and suggest a clinically relevant molecular classification. Furthermore, we show that developing effective targeted approaches in MPT can be possible with genomic profiles and patient-derived xenograft models. The clinical efficacy of targeting PDGFR and PIK3CA/mTOR pathways in MPT should be tested in future clinical trials.

Citation Format: Moon H-G, Yun J, Hong BS, Lee E, Lee H-B, Han W, Kim J-I, Noh D-Y, Heo W, Hur S, Kang W, Lee C. Molecular characterization of human malignant phyllodes tumors reveals potential targeted approaches [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 P2-06-01.

Abstract P3-01-14: Nomogram predicting axillary lymph node metastases to skip intraoperative analysis of sentinel lymph nodes

Background: According to the American College of Surgeons Oncology Group Z0011 trial, complete axillary lymph node dissection (ALND) did not affect survival of patients with clinical T1-T2 invasive breast cancer and one to two sentinel lymph nodes (SLNs) metastases treated with lumpectomy, adjuvant systemic therapy, and radiation therapy. A significant proportion of breast cancer patients may not require ALND, in whom intraoperative analysis of SLNs can be omitted reducing operation time and cost. The aim of this study was to develop a nomogram predicting three or more axillary lymph nodes (ALNs) metastases based on preoperative imaging and clinicopathological factors.

Methods: The training set consisted of 1030 patients with clinical T1-T2 invasive breast cancer and clinically negative ALN who received surgery at Seoul National University Hospital (SNUH) between January 2010 and December 2013. Preoperative imaging techniques including ultrasonography (US), computed tomography (CT), positron emission tomography (PET), and clinicopathological features associated with three or more ALN metastases were evaluated by logistic regression analysis. A nomogram predicting three or more ALNs was developed with statistically significant factors. The validation set consisted of 781 independent patients who received surgery at SNUH between January 2014 and December 2015.

Results: Of the 1030 patients, 89 (8.6%) had three or more ALN metastases. Multivariate analysis showed that three or more ALN metastases was independently associated with tumor size (cm) by US (p&lt;0.001), suspicious ALNs findings in US (p&lt;0.001), chest CT (p&lt;0.001), and PET/CT (≥ 1.4 SUV, p&lt;0.001). Established nomogram evaluating the probability of three or more ALNs metastases includes the above four associated factors. The areas under the receiver operating characteristic (ROC) curve of the nomogram were 0.866 (95% confidence interval [CI] 0.826-0.905) for the training set and 0.867 (95% CI: 0.801-0.932) for the validation set. With cutoff point of 142, false negative ratio is 3.6%, and 8.6% of patients were candidates for intraoperative SLN analysis.

Conclusion: Patients with a strong possibility of three or more ALNs metastases can be identified using preoperative imaging methods including US, CT, and PET. The nomogram measuring this prospect may be valuable in skipping intraoperative analysis of SLNs with advantage of reduced operation time and cost.

Citation Format: Park JH, Ju YW, Kim KE, Rhu J, Kim Y, Lee E, Lee H-B, Moon H-G, Noh D-Y, Han W. Nomogram predicting axillary lymph node metastases to skip intraoperative analysis of sentinel lymph nodes [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 P3-01-14.

Abstract P4-12-11: Cost effectiveness of oncotype Dx for early stage breast cancer under National health insurance

Background : Oncotype Dx is being used increasingly for risk stratification to identify for patients with estrogen receptor-positive (ER+), node negative early-stage breast cancer who are most likely to benefit from adjuvant chemotherapy. In Korea, all citizens are covered by national health insurance (NHI), besides patients just pay 5% of hospital bill, if who diagnosed with cancer. NHI can help solve the financial burden for cancer patients.

So the acquisition costs of the Oncotype DX test are sometimes a barrier to its widespread use. This study was conducted for existing cost-effectiveness analyses of Oncotype DX in Korea.

Methods : We analyzed the hospital expenses of patients who diagnosis with LN-negative ER-positive early-stage breast cancer from October 2010 to October 2016 in Seoul National University Hospital. All patients are possible candidates for adjuvant chemotherapy. Among them 273 patients were tested Oncotype Dx. A cost-utility analysis (CUA) was performed.

We analyzed the hospital expenses of chemotherapy by regimens who underwent adjuvant chemotherapy patients, and costs of accompanying adverse event. Each costs of therapy were derived from the hospital administration and expressed by USD. (KRW convert into USD) We also analyzed every patient charges and real expense.

Result :

Of 273 patients, 39(14.3%) were underwent adjuvant chemotherapy. The patients proportion by regimens are FAC(56.4%), AC(10.3%), AC followed by weekly paclitaxel (5.1%), TC(10.3%), AC followed by docetaxel (5.1%), TC and CMF etc. Each patient's hospital expense are roughly 3,000 USD (2,200 – 4,000 USD), it including all costs of laboratory test, computer tomography, chest x-ray, chemoagents and other medications. Of these costs, patients should pay only 5% so it could be around 150 USD (110-200USD).

Disccusion ;

The economic benefits of Oncotype DX are modelled by an overall reduction in chemotherapy usage, thus avoiding associated costs and disutility, and an increase in chemotherapy usage in the high RS group, reducing the risk of recurrence and improving health outcomes. Several studies shows Oncotype DX has been proposed to better estimate baseline risk and response to chemotherapy, to appropriately target chemotherapy to higher risk patients. In the costeffectiveness model, decision making with Oncotype DX in addition to standard decision-making tools is compared with standard decision making without Oncotype DX. From this study, most patient (234 of 273, 85.7%) who are possible candidates for adjuvant chemotherapy avoiding the treatment. A number of studies have looked at the impact of Oncotype DX on clinical decision making. But under the special environment of Korea that most costs who diagnosed with cancer covered by National Insurance health, it relatively expensive than other conturies. So it deserve much consideration that necessity of further studies and reaserches to develop new tools that could be more reasonable in cost in Korea.

Citation Format: Kim Y, Han W. Cost effectiveness of oncotype Dx for early stage breast cancer under National health insurance [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 P4-12-11.