Factors associated with engraftment success of patient-derived xenografts of breast cancer.

BACKGROUND: Patient-derived xenograft (PDX) models serve as a valuable tool for the preclinical evaluation of novel therapies. They closely replicate the genetic, phenotypic, and histopathological characteristics of primary breast tumors. Despite their promise, the rate of successful PDX engraftment is various in the literature. This study aimed to identify the key factors associated with successful PDX engraftment of primary breast cancer. METHODS: We integrated clinicopathological data with morphological attributes quantified using a trained artificial intelligence (AI) model to identify the principal factors affecting PDX engraftment. RESULTS: Multivariate logistic regression analyses demonstrated that several factors, including a high Ki-67 labeling index (Ki-67LI) (p < 0.001), younger age at diagnosis (p = 0.032), post neoadjuvant chemotherapy (NAC) (p = 0.006), higher histologic grade (p = 0.039), larger tumor size (p = 0.029), and AI-assessed higher intratumoral necrosis (p = 0.027) and intratumoral invasive carcinoma (p = 0.040) proportions, were significant factors for successful PDX engraftment (area under the curve [AUC] 0.905). In the NAC group, a higher Ki-67LI (p < 0.001), lower Miller-Payne grade (p < 0.001), and reduced proportion of intratumoral normal breast glands as assessed by AI (p = 0.06) collectively provided excellent prediction accuracy for successful PDX engraftment (AUC 0.89). CONCLUSIONS: We found that high Ki-67LI, younger age, post-NAC status, higher histologic grade, larger tumor size, and specific morphological attributes were significant factors for predicting successful PDX engraftment of primary breast cancer.

21-gene expression assay and clinical outcomes of premenopausal patients with hormone receptor-positive breast cancer.

The prognostic role of the recurrence score (RS) based on the 21-gene expression assay in premenopausal women is not well delineated, and we investigated the association of outcomes and the RS in premenopausal patients who had 21-gene expression assay at Asan Medical Center, Seoul, Korea, between June 2005 and July 2018. Invasive breast cancer-free survival (IBCFS) by STEEP version 2.0 was compared according to the RS and clinical risk factors. A total of 554 patients were included in our study and 116 patients (20.9%) had age <40 years, 238 patients (43.0%) had luminal B subtype (Ki67 ≥ 20%), and 83 patients (15.0%) had RS >25. All patients received adjuvant tamoxifen ± chemotherapy. Overall, patients with RS >25 showed trend toward worse IBCFS from multivariable analysis (adjusted HR 1.89 [95% CI: 0.95-3.73], P = .069). When comparing outcomes according to age and luminal subtypes, patients with luminal B subtype and age <40 years (n = 60) showed significantly worse outcomes compared to the others (luminal A or luminal B + age ≥40 years, n = 494; adjusted HR 2.95 [95% CI: 1.49-5.82], log-rank P < .001). Among patients with luminal B subtype and age <40 years, there was no significant association observed between IBCFS and the RS (log-rank P = .51). In conclusion, while RS >25 showed association with poor outcomes in premenopausal women, it may have less prognostic significance among those with luminal B subtype and age <40 years.

Persistence and enrichment of dominant T cell clonotypes in expanded tumor-infiltrating lymphocytes of breast cancer.

BACKGROUND: Adoptive cell therapy using tumor-infiltrating lymphocytes (TILs) has shown promising results in cancer treatment, including breast cancer. However, clonal dynamics and clinical significance of TIL expansion ex vivo remain poorly understood. METHODS: We investigated T cell receptor (TCR) repertoire changes in expanded TILs from 19 patients with breast cancer. We compared TCR repertoire of TILs at different stages of expansion, including initial (2W TILs) and rapid expansion (REP TILs), and their overlap with formalin fixed paraffin embedded (FFPE) and peripheral blood. Additionally, we examined differences in TCR repertoire between CD4+ and CD8+ REP TILs. RESULTS: In descending order of proportion, average of 60% of the top 10% clonotypes of FFPE was retained in 2W TIL (60% in TRB, 64.7% in TRA). Among the overlapped clonotypes between 2W TILs and REP TILs, 69.9% was placed in top 30% of 2W TIL. The proportion of clonotypes in 2W TIL and REP TIL showed a significant positive correlation. CD4+ and CD8+ T cells show similar results in diversity and CDR3 length. CONCLUSIONS: Our study traces the changes in TILs repertoire from FFPE to 2W TIL and REP TIL and confirmed that clonotypes with high frequencies in TILs have a high likelihood of maintaining their priority throughout culture process.

Expansion of tumor-infiltrating lymphocytes in non-small cell lung cancer: Clinical potential and efficacy in EGFR mutation subsets.

Our study aimed to expand tumor-infiltrating lymphocytes (TILs) from primary non-small cell lung cancers (NSCLCs) and evaluate their reactivity against tumor cells. We expanded TILs from 103 primary NSCLCs using histopathological analysis, flow cytometry, IFN-γ release assays, cell-mediated cytotoxicity assays, and in vivo efficacy tests. TIL expansion was observed in all cases, regardless of EGFR mutation status. There was also an increase in the median CD4+/CD8+ ratio during expansion. In post-rapid expansion protocol (REP) TILs, 13 out of 16 cases, including all three cases with EGFR mutations, exhibited a two-fold or greater increase in IFN-γ secretion. The cytotoxicity assay revealed enhanced tumor cell death in three of the seven cases, two of which had EGFR mutations. In vivo functional testing in a patient-derived xenograft model showed a reduction in tumor volume. The anti-tumor activity of post-REP TILs underscores their potential as a therapeutic option for advanced NSCLC, irrespective of mutation status.

Expansion of tumor-infiltrating lymphocytes from head and neck squamous cell carcinoma to assess the potential of adoptive cell therapy.

BACKGROUND: Adoptive transfer of in vitro expanded tumor-infiltrating lymphocytes (TILs) has been effective in regressing several types of malignant tumors. This study assessed the yield and factors influencing the successful expansion of tumor-infiltrating lymphocytes (TILs) from head and neck squamous cell carcinoma (HNSCC), along with their immune phenotypes. METHODS: TILs were expanded from 47 surgically resected HNSCC specimens and their metastasized lymph nodes. The cancer tissues were cut into small pieces (1-2 mm) and underwent initial expansion for 2 weeks. Tumor location, smoking history, stromal TIL percentage, human papillomavirus infection, and programmed death-ligand 1 score were examined for their impact on successful expansion of TILs. Expanded TILs were evaluated by flow cytometry using fluorescence-activated cell sorting. A second round of TIL expansion following the rapid expansion protocol was performed on a subset of samples with successful TIL expansion. RESULTS: TILs were successfully expanded from 36.2% samples. Failure was due to contamination (27.6%) or insufficient expansion (36.2%). Only the stromal TIL percentage was significantly associated with successful TIL expansion (p = 0.032). The stromal TIL percentage also displayed a correlation with the expanded TILs per fragment (r = 0.341, p = 0.048). On flow cytometry analysis using 13 samples with successful TIL expansion, CD4 + T cell dominancy was seen in 69.2% of cases. Effector memory T cells were the major phenotype of expanded CD4 + and CD8 + T cells in all cases. CONCLUSION: We could expand TILs from approximately one-third of HNSCC samples. TIL expansion could be applicable in HNSCC samples with diverse clinicopathological characteristics.

Proteomic analysis of breast cancer based on immune subtypes.

BACKGROUND: Immunotherapy is applied to breast cancer to resolve the limitations of survival gain in existing treatment modalities. With immunotherapy, a tumor can be classified into immune-inflamed, excluded and desert based on the distribution of immune cells. We assessed the clinicopathological features, each subtype's prognostic value and differentially expressed proteins between immune subtypes. METHODS: Immune subtyping and proteomic analysis were performed on 56 breast cancer cases with neoadjuvant chemotherapy. The immune subtyping was based on the level of tumor-infiltrating lymphocytes (TILs) and Klintrup criteria. If the level of TILs was ≥ 10%, it was classified as immune-inflamed type without consideration of the Klintrup criteria. In cases of 1-9% TIL, Klintrup criteria 1-3 were classified as the immune-excluded subtype and Klintrup criteria not available (NA) was classified as NA. Cases of 1% TILs and Klintrup 0 were classified as the immune-desert subtype. Mass spectrometry was used to identify differentially expressed proteins in formalin-fixed paraffin-embedded biopsy tissues. RESULTS: Of the 56 cases, 31 (55%) were immune-inflamed, 21 (38%) were immune-excluded, 2 (4%) were immune-desert and 2 (4%) were NA. Welch's t-test revealed two differentially expressed proteins between immune-inflamed and immune-excluded/desert subtypes. Coronin-1A was upregulated in immune-inflamed tumors (adjusted p = 0.008) and α-1-antitrypsin was upregulated in immune-excluded/desert tumors (adjusted p = 0.008). Titin was upregulated in pathologic complete response (pCR) than non-pCR among immune-inflamed tumors (adjusted p = 0.036). CONCLUSIONS: Coronin-1A and α-1-antitrypsin were upregulated in immune-inflamed and immune-excluded/desert subtypes, respectively. Titin's elevated expression in pCR within the immune-inflamed subtype may indicate a favorable prognosis. Further studies involving large representative cohorts are necessary to validate these findings.

Prognostic significance of pretreatment 18F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with T2N1 hormone receptor-positive, ERBB2-negative breast cancer who underwent adjuvant chemotherapy.

PURPOSE: To determine whether tumor uptake of 18F-fluorodeoxyglucose (18F-FDG) is associated with invasive disease-free survival (IDFS) in patients with hormone receptor (HR)-positive ERBB2-negative early-stage breast cancer treated with adjuvant chemotherapy. METHODS: This is a single-center cohort study of women with breast cancer who underwent surgery between 2008 and 2015 at Asan Medical Center, Seoul, Korea. Patients were enrolled if they were diagnosed with HR-positive ERBB2-negative breast cancer with histology of invasive ductal carcinoma, had an American Joint Committee on Cancer pathologic tumor stage of T2N1 with 1-3 positive axillary nodes, underwent preoperative 18F-FDG positron emission tomography/computed tomography (PET/CT), and underwent breast cancer surgery followed by anthracycline- or taxane-based adjuvant chemotherapy. The primary outcome measure was IDFS. The maximum standardized uptake value (SUVmax) was dichotomized using a predefined cut-off of 4.14. RESULTS: A total of 129 patients were included. The median follow-up period for IDFS in those without recurrence was 82 months (interquartile range, 65-106). Multivariable Cox analysis showed that SUVmax was independently associated with IDFS [adjusted hazard ratio 2.49; 95% confidence interval (CI), 1.06-5.84]. Ten-year IDFS estimates via the Kaplan-Meier method were 0.60 (95% CI, 0.42-0.74) and 0.82 (95% CI, 0.65-0.91) for high and low SUVmax groups, respectively. The overall association between SUVmax and IDFS appeared to be consistent across subgroups divided according to age, progesterone receptor status, histologic grade, or presence of lymphovascular invasion. CONCLUSION: High SUVmax on preoperative 18F-FDG PET/CT was independently associated with reduced long-term IDFS in T2N1 HR-positive ERBB2-negative breast cancer patients who underwent adjuvant chemotherapy.

Randomized phase III trial of a neoadjuvant regimen of four cycles of adriamycin plus cyclophosphamide followed by four cycles of docetaxel (AC4-D4) versus a shorter treatment of three cycles of FEC followed by three cycles of docetaxel (FEC3-D3) in node-positive breast cancer (Neo-shorter; NCT02001506).

PURPOSE: To determine whether six cycles of FEC3-D3 has a comparable efficacy to eight of AC4-D4. METHODS: The enrolled patients (pts) were clinically diagnosed with stage II or III breast cancer. The primary endpoint was a pathologic complete response (pCR), and the secondary endpoints were 3 year disease-free survival (3Y DFS), toxicities, and health-related quality of life (HRQoL). We calculated that 252 pts were needed in each treatment group to enable the detection of non-inferiority (non-inferiority margin of 10%). RESULTS: In terms of ITT analysis, 248 pts were finally enrolled. The 218 pts who completed the surgery were included in the current analysis. The baseline characteristics of these subjects were well balanced between the two arms. By ITT analysis, pCR was achieved in 15/121 (12.4%) pts in the FEC3-D3 arm and 18/126 (14.3%) in the AC4-D4 arm. With a median follow up of 64.1 months, the 3Y DFS was comparable between the two arms (75.8% in FEC3-D3 vs. 75.6% in AC4-D4). The most common adverse event (AE) was Grade 3/4 neutropenia, which arose in 27/126 (21.4%) AC4-D4 arm pts vs 23/121 (19.0%) FEC3-D3 arm cases. The primary HRQoL domains were similar between the two groups (FACT-B scores at baseline, P = 0.35; at the midpoint of NACT, P = 0.20; at the completion of NACT, P = 0.44). CONCLUSION: Six cycles of FEC3-D3 could be an alternative to eight of AC4-D4. Trial registration ClinicalTrials.gov NCT02001506. Registered December 5,2013. https://clinicaltrials.gov/ct2/show/NCT02001506.

Breast cancer outcomes following immediate breast reconstruction with implants versus autologous flaps: a propensity score-matched study.

PURPOSE: A large proportion of patients with breast cancer who had mastectomy had undergone breast reconstruction with implants or autologous flaps. However, only a few studies have compared the breast cancer outcomes between the implant-based reconstruction (IBR) and autologous flap reconstruction (AFR). In this study, we retrospectively compared the local recurrence rates, distant metastasis rates, and survival outcomes between immediate IBR and AFR. METHODS: A total of 1530 patients with primary breast cancer who underwent IBR or AFR with nipple-/skin-sparing mastectomy were included. Patients who underwent neoadjuvant systemic therapy were excluded from the study. After propensity score matching by age at diagnosis, T stage, N stage, molecular subtype, mastectomy type, adjuvant radiotherapy status, and follow-up period, 938 patients were 1:1 matched, comprising the well-balanced IBR and AFR groups. Locoregional recurrence-free survival (LRRFS), disease-free survival (DFS), distant metastasis-free survival (DMFS), and breast cancer-specific survival (BCSS) were compared between the matched groups. RESULTS: After matching, the median follow-up periods were 68 months and 71 months for the IBR and AFR groups, respectively. No significant differences were observed between the IBR and AFR groups regarding the local recurrence (7.2% vs. 5.1%; P = 0.175), regional recurrence (2.1% vs. 1.5%; P = 0.463), or distant metastasis (3.2% vs. 3.2%; P = 1.000) rates. Moreover, no significant difference was observed between the IBR and AFR groups in the LRRFS (hazard ratio, 0.691; 95% CI, 0.433-1.102; P = 0.118), DFS (hazard ratio, 0.709; 95% CI, 0.468-1.076; P = 0.104), DMFS (hazard ratio, 1.006; 95% CI, 0.491-2.059; P = 0.987), or BCSS (hazard ratio, 0.445; 95% CI, 0.111-1.786; P = 0.659). CONCLUSION: In this propensity score-matched analysis of oncologic outcomes in patients with primary breast cancer who underwent immediate breast reconstruction with nipple-/skin-sparing mastectomy, no significant differences were observed between the IBR and AFR groups.

Trophoblast cell-surface antigen 2 (TROP2) expression in triple-negative breast cancer.

BACKGROUND: Trophoblast cell-surface antigen 2 (TROP2) is related to tumor proliferation enhancement and poor prognosis. An antibody targeting TROP2 was developed to treat metastatic triple-negative breast cancer (TNBC) which has a limited treatment modality. To characterize the TROP2 expressing tumors in TNBC, we analyzed TROP2 expression in three cohorts; (1) primary tumor without neoadjuvant chemotherapy, (2) primary tumor with neoadjuvant chemotherapy, and (3) metastatic tumor. METHODS: A total of 807 TNBC cases were evaluated for TROP2 immunohistochemical expression. We evaluated the TROP2 H-score distribution in the three cohorts. Tumors were divided into two groups based on TROP2 expression (high vs. low). We analyzed the relationship between clinicopathologic features and markers, including epidermal growth factor receptor, cytokeratin 5/6, p53, and Ki-67, and prognostic significance at high vs. low TROP2 expression. RESULTS: There was no difference in TROP2 H-score distribution between the three cohorts. Moderate-to-strong membranous expression of TROP2 in at least 10% of tumor cells was present in 662 cases (82.0%) in Cohort 1, 59 cases (89.4%) in Cohort 2, and 23 cases (88.5%) in Cohort 3. There was no significant difference in clinicopathologic features between high vs. low TROP2 in all cohorts. TROP2 H-score was an independent poor prognostic factor for overall survival in Cohort 3. CONCLUSIONS: TNBC showed similar TROP2 expression regardless of neoadjuvant treatment or primary tumor/metastasis. Although the prognostic significance of TROP2 expression in metastatic TNBC has been revealed, further evaluation of the predictive value of TROP2 expression for targeted therapy is needed.

Phenotypic Differences of CD103+ Tissue-Resident Memory T Cells Associated with Various Cancers.

BACKGROUND/AIMS: The presence and clinical importance of tissue-resident memory T (TRM) cells have been recently described in association with various cancer types. However, the frequency and the traditional naïve-effector-memory phenotypic characteristics of TRM cells are largely unknown. METHODS: We analyzed single-cell populations of colorectal cancer (CC, n = 18), stomach cancer (SC, n = 13), renal cell carcinoma (RCC, n = 19), and breast cancer (BC, n = 16) by dissociation of tumor tissue with collagenase/hyaluronidase. We investigated populations of naïve, effector, and memory T and TRM cells by flow cytometry. RESULTS: Among CD8- cells, CC was associated with a significantly higher proportion of CD103+ T cells than other tumor types (p < 0.001). Among CD8+ cells, CC and SC were associated with higher CD103+ T-cell proportions than RCC and BC (p < 0.001). Significantly more CD8+ than CD8- cells expressed CD103 (p < 0.001). In association with SC, RCC, and BC, CD8+ T cells had a similar T-cell phenotype composition pattern: fewer effector T cells and more memory-type T cells among CD103+ cells compared with CD103- cells (p < 0.05). Tumors with higher proportion of CD103+ cells had no specific clinicopathologic characteristics than those with lower proportion of CD103+ cells. CONCLUSION: TRM cell abundance and phenotypes varied among CC, SC, RCC, and BC. Further studies regarding the functional differences of TRM associated with various tumors are warranted.

Clinicopathological characteristics and outcomes of malignant adenomyoepithelioma of the breast: a single institution's experience.

BACKGROUND: Malignant adenomyoepithelioma of the breast is a rare tumor and most of relevant literature consists of individual case reports. This study objective was designed to evaluate clinicopathological features and treatment outcomes of 15 cases of malignant adenomyoepithelioma at a single institute. METHODS: A retrospective medical record review was performed for 15 subjects confirmed with malignant adenomyoepithelioma upon postoperative pathological diagnosis at the Asan Medical Center from January 2008 to June 2018. Data regarding age at diagnosis, preoperative biopsy results, operation methods, the status of hormone receptors and HER2, and clinical outcomes were collected. RESULTS: All cases were female patients diagnosed at median age of 50 years. Preoperative core needle biopsy results showed that 40% of the cases (6 out of 15) were benign which was in discordance with the final malignant pathology report. Thirteen cases underwent wide excision with or without sentinel lymph node biopsy (SLNB) and 2 cases had total mastectomy with SLNB. Five of 11 cases (45.5%) were triple negative. Ten of 15 cases underwent postoperative radiation therapy, 3 cases underwent chemotherapy, and 5 cases underwent endocrine therapy. During median follow-up of 55 months, the 5-year overall survival rate was 87.5% and the 5-year disease free survival rate was 91.7%. Two lung metastases developed. One case showed local recurrence 3 years after surgery and radiotherapy and subsequently developed lung metastasis 1 year late. Another case developed lung metastasis one and a half years after surgery in combination with endocrine therapy and neoadjuvant chemotherapy. CONCLUSION: Preoperative core needle biopsy showed inaccurate results for diagnosing malignant adenomyoepithelioma. Malignant adenomyoepithelioma has a high rate of triple negative subtype but has a relatively good prognosis although there is a risk of local and systemic recurrence.

Oncologic Outcomes of Nipple-sparing Mastectomy and Immediate Reconstruction After Neoadjuvant Chemotherapy for Breast Cancer.

OBJECTIVES: To evaluate the oncologic outcomes and risk factors for locoregional recurrence (LRR) and nipple-areola complex recurrence (NR) in a large series of breast cancer patients who underwent nipple-sparing mastectomy (NSM) and immediate reconstruction after neoadjuvant chemotherapy (NACT). SUMMARY OF BACKGROUND DATA: The use of NSM and immediate reconstruction in breast cancer patients receiving NACT is increasing. However, the oncologic safety of this approach is unclear. PATIENTS AND METHODS: A total of 310 breast cancer patients (319 breasts) who underwent NACT and NSM between February 2010 and November 2016 were retrospectively analyzed. Clinical and pathologic factors associated with increased risks of LRR and NR were analyzed using univariate (Chi-square or Fisher exact test) and multivariate (Cox proportional hazard regression model) analyses. RESULTS: During a mean follow-up of 63 ± 22 months, 38 cases had LRR as the first event, including 6 cases of NR as the first event. The 5-year cumulative LRR and NR rates were 11.0% and 1.9%, respectively. In univariate analysis, clinical T stage, pathologic nodal status, histologic grade, lymphovascular invasion, and post-NACT Ki67 status were associated with increased LRR risk, and post-NACT Ki67 status was the only significant risk factor for NR. In multivariate analysis, post-NACT Ki67 ≥10% (hazard ratio, 4.245; 95% confidence interval, 1.865-9.663; P = 0.001) was an independent risk factor for LRR. CONCLUSIONS: NSM and immediate reconstruction seem to be oncologically safe with acceptable LRR and NR rates for appropriately selected breast cancer patients treated with NACT. Post-NACT Ki67 ≥10% was associated with increased risk of LRR or NR, and therefore, necessitates cautious follow-up.

A propensity score-matched comparison of recurrence outcomes after immediate implant vs autologous flap reconstruction in patients receiving neoadjuvant chemotherapy for breast cancer.

PURPOSE: We compared oncologic outcomes between breast cancer patients who underwent immediate implant-based breast reconstruction (IBBR) and those who underwent autologous flap reconstruction (AFR) after neoadjuvant chemotherapy (NACT). METHODS: The study group comprised 536 patients with primary breast cancer who underwent NACT followed by immediate IBBR or AFR. After propensity score matching, 138 patients in the IBBR group and 276 patients in the AFR group were selected for comparisons of locoregional recurrence-free survival (LRRFS), disease-free survival (DFS), distant metastasis-free survival (DMFS), and breast cancer-specific survival (BCSS). RESULTS: No significant differences were observed between the matched groups in locoregional recurrence rates (IBBR vs. AFR: 12.3% vs. 12%; P = 0.915) and distant metastasis (13% vs. 17%; P = 0.293). There was also no significant difference between the groups in LRRFS (P = 0.956), DFS (P = 0.606), DMFS (P = 0.283), or BCSS (P = 0.121). The 5- and 10-year LRRFS rates were 87.6% and 85.9% in the IBBR group, and 87.7% and 86.1% in the AFR group; the 5- and 10-year DFS rates were 79% and 77.5% in the IBBR group, and 77% and 75% in the AFR group; the 5- and 10-year DMFS rates were 85.9% and 85.9% in the IBBR group, and 83.2% and 81.8% in the AFR group; and the 5- and 10-year BCSS rates were 97.8% and 91.3% in the IBBR group, and 91.8% and 86% in the AFR group, respectively. CONCLUSIONS: In this propensity score-matched analysis of oncologic outcomes in breast cancer patients who underwent immediate reconstruction after NACT, no significant differences were observed between the IBBR and AFR groups.

Oncologic Safety of Nipple-Sparing Mastectomy in Patients with Breast Cancer and Tumor-to-Nipple Distance ≤ 1 cm: A Matched Cohort Study.

BACKGROUND: A short tumor-to-nipple distance (TND) is reported as a strong predictor of nipple-areola complex (NAC) involvement. Eligibility for nipple-sparing mastectomy (NSM) remains controversial, especially regarding TND. In this study, we compared long-term oncologic outcomes after NSM between patients with a TND ≤ 1 cm and those with a TND > 1 cm. METHODS: Overall, 1369 patients with primary breast cancer who underwent NSM with immediate reconstruction from March 2003 to December 2015 were included for analysis. After propensity score matching, 495 patients with a TND ≤ 1 cm (group A) and 495 patients with a TND > 1 cm (group B) on imaging were selected to compare long-term oncologic outcomes. RESULTS: After matching, the median follow-up periods for surviving patients were 109 months and 112 months for groups A and B, respectively. There were no significant differences between groups with respect to the 5-year cumulative local recurrence (8.1% vs. 6.3%; p = 0.268), NAC recurrence (5.1% vs. 2.8%; p = 0.072), regional recurrence (2.0% vs. 3.6%; p = 0.125), or distant recurrence (5.9% vs. 4.8%; p = 0.480) rates. Furthermore, no significant differences were observed between the groups with respect to the 10-year local recurrence-free survival (87.1% vs. 90.7%; p = 0.164) or disease-free survival (77.9% vs. 81.6%; p = 0.222) rates. CONCLUSIONS: A preoperative TND ≤ 1 cm on imaging should not be contraindicated to NSM as long as there is no involvement of NAC clinically or on imaging and if retroareolar margins are confirmed to be negative for tumor cells.

Clinicopathological factors associated with tumor-infiltrating lymphocyte reactivity in breast cancer.

BACKGROUND: The clinical significance of adoptive tumor-infiltrating lymphocyte (TIL) therapy has been demonstrated in many clinical trials. We analyzed the in vitro reactivity of cultured TILs against autologous breast cancer cells. METHODS: TILs and cancer cells were cultured from 31 breast tumor tissues. Reactivity of TILs against cancer cells was determined by measuring secreted interferon-gamma. Expression levels of epithelial markers, major histocompatibility complex molecules, and programmed death-ligand 1 (PD-L1) in cancer cells, and T cell markers (memory, T cell activation and exhaustion, and regulatory T cell markers) in expanded TILs were analyzed and compared between the reactive and non-reactive groups. RESULTS: In seven cases, TILs showed reactivity to autologous cancer cells. Six of these cases were associated with triple-negative breast cancer (TNBC). All reactive TNBCs were derived from surgical specimens after neoadjuvant chemotherapy (NAC). Higher expression of Ki67 in tumor tissues and lower expression of PD-L1 in cultured cancer cells were associated with reactivity. Proliferation of reactive TILs was high. High proportions of T cells and PD-1+CD4+ and PD1+CD8+ T cells were associated with reactivity in TNBC cases, while other activation or exhaustion markers were not. CONCLUSION: TILs from approximately half the TNBC cases with NAC showed reactivity against autologous cancer cells. The proportion of PD-1+ T cells was higher in the reactive group. Adoptive TIL therapy combined with PD-1 inhibitors might be promising for TNBC patients with residual tumors after NAC.

Risk stratification system for groups with a low, intermediate, and high risk of subsequent distant metastasis and death following isolated locoregional recurrence of breast cancer.

PURPOSE: This study aimed to identify prognostic factors for long-term outcomes among patients with isolated locoregional recurrence (ILRR) of breast cancer as their first failure event. Many prognostic tools have been developed to inform systemic treatment choices in the adjuvant setting, but tools for predicting post-ILRR prognosis are scarce. METHODS: A total of 495 patients who experienced ILRR after primary surgery at the Asan Medical Center between 1989 and 2008 were included. All patient information and tumor characteristics at the initial surgery were retrieved from our retrospectively collected database, and ILRRs were categorized as local recurrence or regional recurrence (RR). Distant metastasis-free survival (DMFS), breast cancer-specific survival (BCSS), and overall survival post-ILRR were calculated. RESULTS: The median follow-up from the ILRR was 65 months (range 1-249 months), and the 5-year post-ILRR DMFS rate was 58.9%. We found three factors-lymph node metastasis, a disease-free interval < 30 months, and RR as the ILRR type-that were independent prognostic factors for both DMFS [hazard ratio (HR) = 2.08, 1.60, and 1.59; P < 0.001, 0.002, and 0.003, respectively] and BCSS (HR = 2.28, 1.99, and 1.48; P < 0.001, < 0.001, and 0.016, respectively) post-ILRR. Patients were classified into four groups according to the presence these three prognostic indicators: the low-, intermediate-, high-, and extremely high-risk groups. The 5-year post-ILRR DMFS rates were 79.4%, 68.1%, 47.6%, and 36.0%, respectively. CONCLUSIONS: This risk stratification system for subsequent distant metastases after ILRR can be used to make more informed decisions regarding prognosis-based local or systemic management strategies.

Recurrence Outcomes After Nipple-Sparing Mastectomy and Immediate Breast Reconstruction in Patients with Pure Ductal Carcinoma In Situ.

BACKGROUND: Nipple-sparing mastectomy (NSM) has become increasingly prevalent for patients with ductal carcinoma in situ (DCIS) requiring mastectomy. However, few data regarding recurrence outcomes after NSM are available for this patient population. This study evaluated the locoregional recurrence (LRR) rate for patients with pure DCIS who underwent NSM followed by immediate breast reconstruction without adjuvant radiotherapy and investigated potential risk factors for LRR and/or nipple-areola complex recurrence (NR). METHODS: A retrospective chart review was performed for 199 consecutive patients with pure DCIS who underwent NSM and immediate breast reconstruction between March 2003 and December 2015. Risk factors for LRR and NR were analyzed using univariate (Chi square test) and multivariate (Cox model) methods. RESULTS: The median follow-up duration after surgery was 97 months (range, 39-186 months). At 10 years, the LRR rate was 4.5%, and the NR rate was 3%. The univariate analysis showed that high nuclear grade, negative receptor status, positive human epidermal growth factor receptor 2 (HER2) status, and negative hormone receptor/positive HER2 subtype were associated with increased risk for NR. The multivariate analysis demonstrated that negative progesterone receptor status was an independent risk factor for LRR. However, margin status and tumor-to-nipple distance (TND) were not associated with increased risk for either LRR or NR. CONCLUSIONS: The study findings suggest that NSM can be a feasible surgical option even for DCIS with a TND of 1 cm or less if the retroareolar resection margin is negative for malignancy. Determining the molecular subtype of DCIS might be helpful in identifying patients at high risk for recurrence.

Intratumoral CD103-positive tumour-infiltrating lymphocytes are associated with favourable prognosis in patients with triple-negative breast cancer.

AIMS: Cluster of differentiation 103 (CD103), a marker of tissue resident memory T cells, is expressed on subsets of CD8+ T lymphocytes. We investigated the prognostic significance of CD103+ intra-epithelial tumour-infiltrating lymphocytes (iTILs) in invasive breast cancer (IBC). METHODS AND RESULTS: Immunohistochemistry was performed for CD103, CD8 and TGF-ß isoforms (1, 2 and 3) on tissue microarrays of 1187 IBC samples. CD103+ and CD8+ iTILs were present in 904 (76.2%) and 854 (74%) cases with an overall mean ± standard deviation of 38.2 ± 100.2/mm2 and 30.4 ± 89.7/mm2 , respectively. The numbers of CD103+ and CD8+ iTILs were positively correlated, and CD103+ iTILs outnumbered CD8+ iTILs in HER2-positive and triple-negative breast cancer (TNBC). CD103+ and CD8+ iTIL densities were significantly higher in tumours of histological grade 3, absence of lymphovascular invasion, high Ki-67 index, high stromal TIL density or TGF-ß3 expression. High CD103+ iTIL density was associated with better disease-free survival (DFS, P = 0.007), but no significant association was observed for overall survival (OS). Subgroup analysis by cancer molecular subtype showed that CD103+ iTIL count was prognostic only for TNBC (OS, P = 0.035; DFS, P = 0.009). CD8+ iTIL density was significant for DFS, but not for OS, in the entire cohort and TNBC. In multivariate analysis, CD103+ iTIL density was an independent prognostic factor of OS (P = 0.02) and DFS (P = 0.007) in TNBC, while CD8+ iTIL density was not significant for survival. CONCLUSIONS: CD103 iTIL density can serve as a predictor of good prognosis in patients with TNBC.

Prediction of prognostic signatures in triple-negative breast cancer based on the differential expression analysis via NanoString nCounter immune panel.

BACKGROUND: Triple-Negative Breast Cancer (TNBC) is an aggressive and complex subtype of breast cancer. The current biomarkers used in the context of breast cancer treatment are highly dependent on the targeting of oestrogen receptor, progesterone receptor, or HER2, resulting in treatment failure and disease recurrence and creating clinical challenges. Thus, there is still a crucial need for the improvement of TNBC treatment; the discovery of effective biomarkers that can be easily translated to the clinics is essential. METHODS: We report an approach for the discovery of biomarkers that can predict tumour relapse and pathologic complete response (pCR) in TNBC on the basis of mRNA expression quantified using the NanoString nCounter Immunology Panel. To overcome the limited sample size, prediction models based on random Forest were constructed using the differentially expressed genes (DEGs) as selected features. We also evaluated the differences between pre- and post-treatment groups aiming for the combinatorial assessment of pCR and relapse using additive models in edgeR. RESULTS: We identify nine and 13 DEGs strongly associated with pCR and relapse, respectively, from 579 immune genes in a small number of samples (n = 55) using edgeR. An additive model for the comparison of pre- and post-treatment groups via the adjustment of the independent subject in the relapse group revealed associations for 41 genes. Comprehensive analysis indicated that our prediction models outperformed those constructed using features extracted from the existing feature selection model Elastic Net in terms of accuracy. The prediction models were assessed using a randomization test to validate the robustness (empirical P for the model of pCR = 0.015 and empirical P for the model of relapse = 0.018). Furthermore, three DEGs (FCER1A, EDNRB, and TGFBI) in the model of relapse showed prognostic significance for predicting the survival of patients with cancer through Cox proportional hazards regression model-based survival analysis. CONCLUSION: Gene expression quantified via the NanoString nCounter Immunology Panel can be seamlessly analysed using edgeR, even considering small sample sizes. Our approach provides a scalable framework that can easily be applied for the discovery of biomarkers based on the NanoString nCounter Immunology Panel. DATA AVAILABILITY: The source code will be available from github at https://github.com/sungheep/nanostring .