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Purpose: To investigate the long-term clinical outcomes of transplanted amniotic membrane in patients who underwent permanent amniotic membrane transplantation (P-AMT) on cornea.Methods: From April 2014 to March 2021, medical records and digital photographs of 68 patients (72 eyes) who underwent P-AMT were analyzed retrospectively. The duration of complete re-epithelization of cornea and wearing therapeutic contact lense (T-lens) after surgery were investigated, the size of preserved amniotic membrane (AM) excluding the melted portion was analyzed using the Image J program every year up to 6 years after surgery, and it was compared by dividing into a single-layer group and a double-layer group. In addition, when the AM melts, the cause, time, and related factors of melting were analyzed.Results: The average duration to complete re-epithelialization after surgery was 12.2 ± 11.0 days, and T-lens were worn on average up to 8.7 ± 8.5 months after surgery. In total group, the average ratio of preserved AM annually up to 6 years after surgery was 94.9%, 94.3%, 97.8%, 96.4%, 95.8%, 91.6% respectively, and there was no significant difference between the single-layer group and the double-layer group. AM melting appeared in 38.9% (28 eyes) of the total group, and melting was first observed on average 16.4 ± 17.2 months after surgery. The formation and rupture of bullae was the most common cause of melting at 71.4% (20 eyes), and there were no statistically significant related factors involved in the formation of bullae.Conclusions: In the case of P-AMT performed in various diseases of the cornea, the transplanted AM is partially melt but considered to be well preserved up to 6 years after surgery to form a stable ocular surface.

Although prospective randomized clinical trials have reported that the use of prophylactic tamoxifen in patients at a high risk of breast cancer is associated with an increased risk of cataracts development, such findings are inconsistent. This study aimed to clarify the relationship between adjuvant tamoxifen use and cataracts risk using a nationwide longitudinal population-based registry.This retrospective cohort study was conducted using the Korean National Health Insurance claims database over a 15-year period (January 2007-December 2021). Data from all female patients diagnosed with ductal carcinoma in situ (DCIS) between 2009 and 2015 were extracted. We evaluated the incidence of cataracts diagnosis and surgery after adjuvant tamoxifen administration in patients with DCIS.A total of 43,434 patients who met the inclusion criteria were diagnosed with DCIS between 2009 and 2015. Data from 2849 patients receiving tamoxifen and 1615 patients not receiving tamoxifen were analyzed before matching. After matching for comorbidities, type of breast surgery, and age, both groups consisted of 1597 patients. Both before and after matching, adjuvant tamoxifen was not a significant factor for an increased risk of cataracts diagnosis alone or with surgery.Our study showed that adjuvant tamoxifen was not a risk factor for increased cataracts diagnosis and surgery in patients with DCIS. This finding provides a basis for physicians to reduce their ocular toxicity concerns regarding the risk of patients developing cataracts by tamoxifen treatment.

Older patients with breast cancer have good prognosis and most die from diseases other than breast cancer. Previous studies suggested that the surgical extent in older patients could be reduced. We aimed to compare survival outcomes in patients aged ≥70 years with clinically node-negative breast cancer, based on whether axillary surgery was performed.A total of 2,995 patients with breast cancer aged ≥70 years who underwent breast surgery were included in the Korean Breast Cancer Registry. Patients were classified into two groups according to the performance of axillary surgery. We used propensity score matching for demographic and treatment factors to minimize selection bias. We compared the 5-year overall survival (OS) and breast cancer-specific survival (BCSS).Among 708 patients after 3:1 propensity score matching, 531 underwent breast surgery with axillary surgery and 177 underwent breast surgery alone. Of all patients, 51.7% had T1 stage, and 73.2% underwent mastectomy. Approximately 31.2% of patients received chemotherapy. Among patients who did not undergo axillary surgery, the 5-year OS and BCSS rates were 85.2% and 96.7%, respectively. The hazard ratio of axillary surgery for OS was 0.943 (95% confidence interval 0.652-1.365, p = 0.757), indicating no significant difference between two groups.Our study demonstrates that axillary surgery in a matched cohort of older patients with breast cancer and clinically negative nodes does not provide a survival benefit compared to patients undergoing breast surgery alone. These findings suggest that axillary surgery may be safely omitted in a select group of patients aged ≥70 years with clinically node-negative cancer. Further studies are needed to identify potential candidates for omitting axillary surgery.

Background: In human epidermal growth factor receptor 2 (HER2)-positive early stage breast cancer, prediction of trastuzumab-related cardiac toxicity remains a challenge. The coronary calcium artery (CAC) reflects the total coronary plaque burden, which predicts the risk of atherosclerosis. We investigated the prediction of left ventricular ejection fraction (LVEF) decline in breast cancer according to CAC scores. Methods: A total of 347 patients were enrolled from Seoul St Mary’s Hospital between January 2010 and December 2019. Chest computed tomography (CT) was performed at a single tertiary center. Patients who received trastuzumab for HER2-positive early breast cancer were included in this study. Results: Of the 347 patients, 312 and 35 had CAC scores of 0 and ≥1, respectively. The CAC ≥1 group was associated with older age, body mass index, and receipt of left breast irradiation. The CAC ≥1 group was significantly associated with LVEF decline (absolute value, ≤50%) (hazard ratio [HR] 12.038, 95% confidence interval [CI] 2.845–50.937, p = 0.001), LVEF decline (absolute value, ≤55%) (HR 4.439, 95% CI: 1.787–11.028, p = 0.001), and decline in LVEF of ≥10% points compared with baseline echography (HR 5.083, 95% CI: 1.658–15.582, p = 0.004). Even after adjusting for other clinical factors, CAC ≥1 remained a significant predictor of decreased LVEF. Conclusion: Our findings suggest that the CAC score is a significant predictor of cardiac toxicity following trastuzumab treatment in HER2-positive breast cancer. Therefore, CAC measurement could reduce cardiac toxicity by distinguishing patients at high risk for trastuzumab.

Purpose: To investigate the clinical efficacy of MS-Amnion amniotic membrane contact lenses.Methods: MS-Amnion amniotic membrane contact lenses were placed for 1 week in patients with severe superficial punctate keratitis or corneal epithelial defects that did not respond to medical treatment. Eighteen eyes followed-up for ≥3 months were evaluated in terms of the best-corrected visual acuity, tear break-up time, and corneal sensation and opacity before and after application of the MS-Amnion amniotic membrane contact lens. The success and recurrence rates, and complications during follow-up, were recorded.Results: Out of 18 eyes, 15 (83.3%) healed within 2 weeks without any treatment other than the amniotic membrane; three eyes (16.7%) were unresponsive, and thus underwent temporary amniotic membrane transplantation. Recurrence developed in three eyes (20%). The amniotic membrane contact lens dropped out in five eyes (27.8%) and folded over in two (11.1%). The mean best-corrected visual acuity improved from 0.89 to 0.27 logarithm of the minimal angle of resolution after 3 months, while the mean corneal opacity decreased from 0.38 to 0.11 after 3 months; the changes were statistically significant. The tear break-up time and corneal sensation also improved, but they were not statistically significant. We encountered no significant complications.Conclusions: The MS-Amnion amniotic membrane contact lenses can heal the amniotic membrane and do not require suturing when applied in the outpatient clinic. This may be beneficial for patients with intractable ocular surface disorders.

Radiation-induced anti-tumor responses occur in the immune system, particularly in peripheral blood mononuclear cells (PBMCs), which are overly sensitive to ionizing radiation. Irradiation of PBMCs is associated with inflammation. We assessed the association between radiotherapy (RT)-induced changes in peripheral blood cells, utilizing the lymphocyte-to-monocyte ratio (LMR), and survival outcome in breast cancer patients who underwent breast-conserving surgery followed by adjuvant RT.LMR values were obtained from retrospective data, and serial sampling of blood before the first and last RT sessions was performed. The cut-off point was analyzed using the Youden index and receiver operating characteristic curve. Recurrence-free survival (RFS) and overall survival (OS) were the main outcomes.Patients with RT-induced low LMR had significantly shorter RFS (hazard ratio [HR] 2.730; 95% confidence interval [CI], 1.607-4.636, P = 0.0002) and OS (HR 2.890; 95% CI 1.410-5.924, P = 0.0038). The results were more robust in the subgroup of patients who received chemotherapy. Multivariate analysis showed that lymph node metastasis and RT-induced low LMR were associated with poor RFS (HR 1.763; 95% CI, 1.017-3.059, P = 0.044) and OS (HR 2.254; 95% CI, 1.060-4.796, P = 0.035).This study demonstrates that RT-induced low LMR is a valid prognostic marker for recurrence and survival in breast cancer patients undergoing RT.

Background:Ocular neuropathic pain (ONP) has various etiologies and substantially decreases the quality of life of patients. Theclinical management of patientswith ONP has been debated. Based on the convergence in the trigeminocervical complex, this study evaluated the effect of repeated greater occipital nerve block (GONB) for ONP. Methods:Two hundred and four patients received a GONB every two weeks, up to 10 times. The posttreatmentoutcomes were measured using a pain relief scale at the next visit, with the first visit as the baseline (10). Results: The differences and magnitude of decrease in the overall pain relief scale score (estimate=-0.55, pConclusions:Although it is premature to recommend repeated GONB for the management of ONP, it can be used as an effective technique. Trial registration: Registered this study in the Clinical Research Information Service of Republic of Korea (no. KCT0007615) on October 26, 2022

Purpose: To investigate the long-term efficacy and stability of the use of various reinforcement material grafts on scleromalacia.Methods: This retrospective study was conducted on scleromalacia patients who underwent surgical treatment with reinforcement material grafts from January 2012 to March 2019. The choice of amniotic membrane, Tenon’s capsule, acellular sclera, or collagen matrix implanted in the area of scleromalacia was made based on disease severity. Amniotic membrane transplantation with a pedicular rotatory inferior conjunctival flap was performed to prevent having a bare sclera. The patient demographics, cause of scleromalacia, best-corrected visual acuity (BCVA), recurrence rate, postoperative complications, and restoration appearance were evaluated.Results: A total of 58 patients (58 eyes) were enrolled in this study. The mean age of patients was 65.7 ± 9.6 years, and 32 patients (55.2%) were women. The mean follow-up period was 28.1 ± 17.3 months. The most common cause of scleromalacia was pterygium operation (53 patients, 91.4%). The reinforcement materials were mainly amniotic membrane (31 patients, 53.4%) and acellular sclera (15 patients, 25.7%). There was no recurrence of scleromalacia or structural instability during the follow-up period. The preoperative and postoperative mean BCVA values were 0.24 ± 0.24 and 0.21 ± 0.23 logMAR, respectively. Wound dehiscence (three patients, 5.2%) and conjunctival cyst (three patients, 5.2%) occurred with the highest frequency.Conclusions: The use of the appropriate reinforcement material graft according to the severity of scleromalacia and amniotic membrane transplantation using a pedicular rotatory inferior conjunctival flap to prevent a bare sclera can be effective for treating scleromalacia, without long-term recurrence.

Immune checkpoint inhibitors (ICI) have demonstrated efficacy in the treatment of solid cancers. However, there is no unified predictive biomarker available for ICIs. We aimed to compare the prognostic impact of using three PD-L1 antibodies (SP142, SP263, and 22C3) for immunohistochemical (IHC) analysis. We retrospectively investigated tumor tissues derived from 316 breast cancer cases, by constructing tissue microarrays and by performing IHC staining. The immune-cell expression rate (for SP142 and SP263) and combined proportional score (for 22C3) were evaluated, and survival outcomes were analyzed. Prediction models were developed, and values of Harrel’s c-index and areas under curves were calculated to compare the discriminatory power. Negative PD-L1 expression based on the 22C3-IHC assay was determined to be an independent prognostic marker for recurrence-free survival (RFS, P = 0.0337) and distant metastasis-free survival (DMFS, P = 0.0131). However, PD-L1 expression based on SP142- and SP263-IHC assays did not reveal a prognostic impact. Among the three antibodies, adding PD-L1 expression data obtained via 22C3-IHC assay to the null model led to a significant improvement in the discriminatory power of RFS and DMFS. We suggest that PD-L1 expression based on the 22C3-IHC assay is a superior prognostic marker than that based on SP142- and SP263-IHC assays.

The purpose of this study is to investigate imaging characteristics of young age breast cancer (YABC) focusing on correlation with pathologic factors and association with disease recurrence. From January 2017 to December 2019, patients under 40 years old who were diagnosed as breast cancer were enrolled in this study. Morphologic analysis of tumor and multiple quantitative parameters were obtained from pre-treatment dynamic contrast enhanced breast magnetic resonance imaging (DCE-MRI). Tumor-stroma ratio (TSR), microvessel density (MVD) and endothelial Notch 1 (EC Notch 1) were investigated for correlation with imaging parameters. In addition, recurrence associated factors were assessed using both clinico-pathologic factors and imaging parameters. A total of 53 patients were enrolled. Several imaging parameters derived from apparent diffusion coefficient (ADC) histogram showed negative correlation with TSR; and there was negative correlation between MVD and Ve in perfusion analysis. There were nine cases of recurrences with median interval of 16 months. Triple negative subtype and low CD34 MVD positivity in Notch 1 hotspots showed significant association with tumor recurrence. Texture parameters reflecting tumor sphericity and homogeneity were also associated with disease recurrence. In conclusion, several quantitative MRI parameters can be used as imaging biomarkers for tumor microenvironment and can predict disease recurrence in YABC.

BackgroundAlthough previous studies demonstrated no association between depression and tamoxifen in patients with breast cancer, there is still a limited amount of long-term follow-up data. This study aimed to evaluate the relationship between endocrine treatment and the risk of depression.MethodsThis nationwide population-based cohort study used data obtained over a 14-year period (January 2007 to December 2021) from the Korean National Health Insurance claims database. All female patients with breast cancer were included. We examined the incidence of depression in patients who underwent endocrine treatment, and those who did not undergo endocrine treatment constituted the control group.ResultsThe data from 11,109 patients who underwent endocrine treatment and 6,615 control patients between 2009 and 2010 were analyzed. After performing matching for comorbidities and age, both groups comprised 6,532 patients. The median follow-up were 119.71 months. Before and after matching was performed, the endocrine treatment was not a significant risk factor for developing depression (p=0.7295 and p=0.2668, respectively), nor was it a significant factor for an increased risk for suicide attempt (p=0.6381 and p=0.8366, respectively).ConclusionsUsing a real-world population-based cohort, this study demonstrated that there is no evidence that the endocrine treatment increases the risk of depression.

Despite being a standard treatment option in breast cancer, immune checkpoint inhibitors (ICIs) are only efficacious for a subset of patients. To gain a better understanding of the antitumor immune response in breast cancer, we examined the heterogeneity of CD8

Despite being a standard treatment option in breast cancer, immune checkpoint inhibitors (ICIs) are only efficacious for a subset of patients. To gain a better understanding of the antitumor immune response in breast cancer, we examined the heterogeneity of CD8 + T cells in tumors, metastatic lymph nodes (mLNs), and peripheral blood from patients with early breast cancer ( n = 131). Among tissue-resident memory CD8 + T (T RM ) cells, including virus- and tumor-specific CD8 + T cells, CD39 expression was observed in a tumor-specific and exhausted subpopulation in both tumors and mLNs. CD39 + T RM cells from tumors and mLNs exhibited a phenotypic similarity and clonally overlapped with each other. Moreover, tumor or mLN CD39 + T RM cells clonally overlapped with CD39 − T RM and non-T RM cells in the same compartment, implying a tissue-specific differentiation process. These inter-subpopulationally overlapping CD39 + T RM clonotypes were frequently detected among effector memory CD8 + T cells in peripheral blood, suggesting a systemic clonal overlap. CD39 + T RM cell enrichment was heterogeneous among molecular subtypes of breast cancer, which is associated with the different role of antitumor immune responses in each subtype. In vitro blockade of PD-1 and/or CTLA-4 effectively restored proliferation of CD39 + T RM cells and enhanced cytokine production by CD8 + T cells from tumors or mLNs, particularly in the presence of CD39 + T RM enrichment. This suggests that CD39 + T RM cells have a capacity for functional restoration upon ICI treatment. Thus, our study indicates that CD39 + T RM cells with a clonal overlap across compartments are key players in antitumor immunity in breast cancer.

Although adjuvant chemotherapy (CTx) is still recommended for high-risk patients with hormone receptor-positive and human epidermal receptor (HER)-2-negative breast cancer, recent studies found that selected patients with low disease burden may be spared from CTx and receive hormonal treatment (HT) alone. This study aims to evaluate the trends of treatment (CTx + HTThe Korean Breast Cancer Society Registry was queried (2000 to 2018) for women with pT1-2N0-1 hormone receptor-positive and HER2-negative disease who underwent surgery and adjuvant systemic treatment (CTx and HT). Clinicopathologic factors, change in pattern of treatment over time, and OS for each treatment option were analyzed.A total of 40,938 women were included in the study; 20,880 (51.0%) received CTx + HT, while 20,058 (49.0%) received HT only. In recent years, there has been a steady increase in the use of HT alone, from 21.0% (2000) to 64.6% (2018). In Cox regression analysis, age, type of breast and axillary operations, T and N stages, body mass index, histologic grade, and presence of lymphovascular invasion were prognostic indicators for OS. There was no significant difference between CTx + HT and HT alone in terms of OS (P = 0.126).Over the years, there has been a shift from CTx + HT to HT alone without a significant difference in OS. Therefore, HT alone could be a safe treatment option in selected patients, even those with T2N1 disease.

Background There is no proven primary preventive strategy for doxorubicin‐induced subclinical cardiotoxicity (DISC), especially among patients without a cardiovascular (CV) risk. We investigated the primary preventive effect on DISC of the concomitant use of angiotensin receptor blockers (ARBs) or beta‐blockers (BBs), especially among breast cancer patients without a CV risk. Methods A total of 385 patients who were scheduled for doxorubicin chemotherapy were screened. Among them, 195 patients of the study populations were included and were randomly divided into two groups [candesartan 4 mg q.d. vs. carvedilol 3.125 mg q.d.] and patients who were unwilling to take one of the medications were evaluated as controls. The primary outcomes were the incidence of early DISC (DISC developing within 6 months after chemotherapy), and late DISC (DISC developing only at least 12 months after chemotherapy). Result Compared with the control group (8 out of 43 patients (18.6%)), only the candesartan group (4 out of 82 patients (4.9%)) showed a significantly lower incidence of early DISC (p = 0.022). Compared with the control group, the candesartan group demonstrated a significantly reduced decrease in left ventricular ejection fraction (LVEF) throughout the study period [−1.0% vs. −3.00 (p, This study showed that low cumulative doses of doxorubicin were associated with the early development of subclinical cardiotoxicity in breast cancer patients without cardiovascular risk. Concomitant treatment with low‐dose candesartan may attenuate and even reverse early left ventricular systolic dysfunction in these patients.

AIM: To assess the clinical performance of a multifocal corneoscleral lens for the presbyopia correction. METHODS: A prospective clinical trial of the Onefit™ A multifocal corneoscleral lens was conducted with 40 participants with presbyopia. At 4wk of continuous wear of the corneoscleral lens, changes in the distance, intermediate, and near visual acuity (VA) were evaluated. The safety of the corneoscleral lens, central corneal thickness (CCT), corneal endothelial cell count, binocular stereopsis, tear film break-up time (BUT), corneal staining, corneal edema, corneal neovascularization (NV), and conjunctival hyperemia were examined. In addition, a subjective questionnaire addressing satisfaction (rated from 1 to 5 points) and discomfort (rated from 1 to 5 points) was administered. RESULTS: Forty participants were enrolled in this study. Six participants were excluded because of poor compliance with lens fitting (n=2) and loss to follow-up (n=4). The mean age of the participants was 53.0±4.9y. At 4wk of continuous wear of the corneoscleral lens, the best corrected far, intermediate, and near VA was 0.08±0.11, 0.10±0.12, and 0.10±0.12 logMAR, respectively. These results were significant improvements over the baseline uncorrected VA (far: P=0.004; intermediate: P=0.004; near: P=0.002). CCT, corneal endothelial cell count, binocular stereopsis, BUT, corneal staining, corneal edema, corneal NV, and conjunctival hyperemia were not significantly different between baseline and after corneoscleral lens use. The average satisfaction scores for fit sensation; corrected far, intermediate, and near VA; and ease of handling were 4.1, 3.4, 3.6, 3.5, and 3.4, respectively. The average discomfort scores for dryness, irritation, foreign body sensation, redness, fogging, and halo were 1.7, 1.8, 1.5, 1.7, 1.7, and 1.3, respectively. CONCLUSION: Far, intermediate, and near VA are improved in presbyopic patients with the multifocal corneoscleral lens compared to uncorrected baseline VA, without adverse ocular effects. This evidence supports the safety and effectiveness of presbyopia correction with multifocal corneoscleral lenses.

Introduction Incidence of microinvasive Breast cancer (DCISM) along with ductal carcinoma in situ is increasing due to mammographic screening. However, DCISM is not a common pathologic entity and surgical management of the axilla, overall treatment, and prognosis of this entity still remains unclear. Our study aims to determine whether sentinel lymph node biopsy (SLNB) is necessary for all DCISM patients and analyze the characteristics of lymph node-positive patients among DCISM patients to identify risk factors associated with lymph node metastasis. Materials and MethodsA total of 184,007 Breast cancer patients treated were registered in the Korean Breast Cancer Society Registry between 1978 to 2020. A retrospective review of the database was performed and the analysis includes diagnostic and clinic-pathologic characteristics such as positive lymph node and immunohistochemistry. A univariate analysis was carried out to determine associations between lymph node positivity and the clinical variables via Fisher’s exact test.ResultsOf the 184,007 patients, 2,556 (1.4%) breast cancer patients were classified as DCISM and 134 (5.2%) had at least one lymph node (node-positive), while 2,422 were node-negative patients. We found statistically significant results with hormone receptor status between node-positive and node-negative patients. Estrogen receptor (ER) and progesterone receptor (PR)-negative cases were associated with lower ORs (ER: OR=0.63, 95CI=0.43-0.92, P=0.016; PR: 0.67, 0.46-0.96, 0.026, respectively). A particularly interesting finding is that human epidermal growth factor receptor 2 (HER2)-negative cases were associated with higher OR (HER2: 2.03, 1.36-3.06, 0.001), suggesting hormone receptor status could be useful to identify potential lymph node metastases.ConclusionOur study suggests that we could omit axillary staging in DCISM patients, and consider optional SLNB in patients with ER, PR, and HER2 status with other overrepresented clinical entities such as palpable mass, BMI, and histologic grade.KeywordsMicroinvasive ductal carcinoma, Sentinel lymph node biopsy, lymph node metastasis Citation Format: Pill Sun Paik, Min Kyung Cho, Juneyoung Ahn, Chang Ik Yoon, Tae-Kyung Yoo, Woo-Chan Park. Risk factors for lymph node metastasis and the role of SLNB in microinvasive breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS1-54.

Purpose Pathological complete response (pCR) predicts improved survival in breast cancer patients undergoing neoadjuvant chemotherapy (NAC). However, the prognosis of patients with non-pCR remains unclear. The aim of this study was to evaluate the effect of radiological response pattern on breast cancer patients’ outcome. Method A total of 396 breast cancer patients who underwent neoadjuvant chemotherapy between 2010-2017 at Seoul St. Mary’s Hospital were retrospectively reviewed. Among them, patients who underwent 4-6 cycles of neoadjuvant chemotherapy and underwent response evaluation every 2 cycles using breast MRI were included for analysis. Early and late response ratio was calculated from breast MR images using the longest diameter of the main tumor. Early response ratio was calculated as post-2 cycle NAC / pre-NAC ratio. Late response ratio was calculated as post-4 cycle NC / post-2 cycle NAC ratio. Radiological response pattern was divided into three groups; fast-slow responder meaning early response ratio > late response ratio + 20%, slow-fast responder meaning late response ratio > early response ratio + 20% and constant responder meaning the difference between initial response ratio and later response ratio is lower than 20%. Survival analysis was done using the Kaplan-Meier method and multivariate analysis by Cox regression. Disease-free survival (DFS) was defined as locoregional recurrence, contralateral breast recurrence and distant metastasis. Result A total of 177 patients were included for analysis. Among them 19 (10.7%) patients were pCR, 122 (68.9%) patients had partial response, 29 (16.4%) patients had stable disease and 7 (4.0%) patients had progressive disease. Median follow-up period was 50 months (range, 3-112 months). Radiological response pattern was significantly associated with disease-free survival in univariate analysis (p=0.042). Fast-slow responders had significantly worse disease-free survival (DFS) in univariate analysis compared to slow-fast responders and constant responders (p=0.042, 5-year DFS 67.6%, 88.3% 67.6%). Radiological response pattern continued to be statistically significant by multivariable analysis (p=0.037). Conclusion Our results showed that fast-slow responders have worse survival compared to constant or slow-fast responders. Radiological response patterns may be useful to more accurately assess prognosis, especially when considering adjuvant chemotherapy. Citation Format: Juneyoung Ahn, Tae-kyung Yoo, Pill Sun Paik, Min Kyung Cho, Chang Ik Yoon, Woo Chan Park. Radiological response pattern predicts disease-free survival in breast cancer patients undergoing neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS13-45.

In this paper, we propose a multi-chip architecture based on parallel frame rendering suitable for real-time ray tracing in dynamic scenes. In multi-chip architecture with the commonly used screen partitioning method, the acceleration structure data, such as a tree, updated in a dynamic scene must be transmitted to each chip. In the proposed frame division method, a tree build and ray tracing are performed on the same chip, and each frame is allocated to a predesignated multi-chip. Thus, the proposed method can achieve scalable performance improvement not only of ray tracing but also of a tree build. We implemented a multi-chip architecture on three field-programmable gate array (FPGA) boards and built 12 ray-tracing cores in the FPGA chip of each board. This configuration means that the inter-chip operates using the frame division method, while the inner chip operates using the screen partitioning method. The results of experiments showed that the proposed multi-chip architecture improved frames per second (FPS) performance by an average of 2.83 times compared to a single-chip architecture.