International retrospective cohort study of locoregional and systemic therapy in oligometastatic breast cancer (OLIGO-BC1)

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Background: Systemic therapy is the standard care in metastatic breast cancer (BC). However, retrospective studies demonstrated survival benefits of locoregional and systemic (combination) therapy in oligometastatic BC. To clarify it, the Federation of Asian Clinical Oncology conducted an international retrospective cohort study (OLIGO-BC1) (UMIN No.000030047). Methods: Oligometastatic BC patients diagnosed from 2007 to 2012 were registered. “Oligometastases” is defined as low volume metastatic disease with limited number and size of metastatic lesions up to five and not necessarily in the same organ by the ABC guidelines. Overall survival (OS) from the diagnosis of oligometastases was the primary endpoint and compared between combination and systemic therapy using a log-rank test. Assuming the 5-year OS of 50% and 40%, respectively, 698 patients were required to achieve 80% power to detect the superiority of combination therapy, at a two-sided significance level. A multivariable Cox regression model with stratification by country was performed to estimate hazard ratio (HR) for therapy and other risk factors. Results: While 1,262 cases had been registered from February 2018 to May 2019, 1,200 remained for analysis after exclusion of unavailable cases. Among them, 573, 529 and 98 cases were registered from China, Japan and Korea, respectively. Luminal BC was recorded in 526 cases (44%), luminal-HER2 BC in 189 (16%), HER2 BC in 154 (13%), triple-negative BC in 166 (14%) and others in 165 (13%). One oligometastatic BC was found in 578 cases, 2 in 289, 3 in 154, 4 in 102 and 5 in 77. Bone metastases were recorded in 301 cases, visceral metastases in 387, locoregional recurrence in 25, local recurrence in 83 and multiple metastatic sites in 404. Combination therapy was performed in 595 cases and systemic therapy in 404. At median follow-up of 4.9 years, 5-year OS was 59.6% and 41.9%, respectively (p < 0.01). An adjusted HR was 0.61 (95% CI: 0.51, 0.74). Type of systemic therapy, younger age, ECOG performance status 0, stage I BC, non-triple negative subtype, fewer metastatic sites, local recurrence and longer disease-free interval were significantly favorable prognostic factors. Discussions: Oligometastatic BC under some conditions seems to be curable. Taken together with recent molecular targeted therapy, locoregional therapy will be advantageous to conquer it. Conclusions: Combination therapy is a promising strategy for patients with oligometastatic BC.

Annual report of the Japanese Breast Cancer Society registry for 2016

The Japanese Breast Cancer Society (JBCS) registry began data collection in 1975, and it was integrated into National Clinical Database in 2012. As of 2016, the JBCS registry contains records of 656,896 breast cancer patients from more than 1400 hospitals throughout Japan. In the 2016 registration, the number of institutes involved was 1422, and the total number of patients was 95,870. We herein present the summary of the annual data of the JBCS registry collected in 2016. We analyzed the demographic and clinicopathologic characteristics of registered breast cancer patients from various angles. Especially, we examined the registrations on family history, menstruation, onset age, body mass index according to age, nodal status based on tumor size and subtype, and proportion based on ER, PgR, and HER2 status. This report based on the JBCS registry would support clinical management for breast cancer patients and clinical study in the near future.

Ki-67 response-guided preoperative chemotherapy for HER2-positive breast cancer: results of a randomised Phase 2 study

BACKGROUND

The effectiveness of a therapeutic strategy that switches chemotherapy, based on Ki-67 tumour expression after initial therapy, relative to that of standard chemotherapy, has not been evaluated.

METHODS

Patients were randomly assigned to the control arm or the Ki-67 response-guided arm (Ki-67 arm). Primary tumour biopsies were obtained before treatment, and after three once-weekly doses of paclitaxel and trastuzumab to assess the interim Ki-67 index. In the control arm, paclitaxel and trastuzumab were continued for a total of 12 doses, regardless of the interim Ki-67 index. In the Ki-67 arm, subsequent treatment was based on the interim Ki-67 index. Ki-67 early responder is defined as the absolute Ki-67 value that was <10%, and the percentage of Ki-67-positive tumour cells was reduced by >30% compared with before treatment. Early Ki-67 responders continued to receive the same treatment, while early Ki-67 non-responders were switched to epirubicin plus cyclophosphamide. The primary endpoint was the pathological complete response (pCR) rate.

RESULTS

A total of 237 patients were randomised. There was almost linear correlation between the Ki-67 reduction rate at interim assessment and the pCR rate. The pCR rate in Ki-67 early non-responders in the Ki-67 arm was inferior to that in the control arm (44.1%; 31.4-56.7; P = 0.025).

CONCLUSIONS

The standard chemotherapy protocol remains as the recommended strategy for patients with HER2-positive breast cancer.

CLINICAL TRIAL REGISTRATION

Clinical Trial Registration: UMIN-CTR as UMIN000007074.

A double-blind, randomized, multicenter phase 3 study of palonosetron vs granisetron combined with dexamethasone and fosaprepitant to prevent chemotherapy-induced nausea and vomiting in patients with breast cancer receiving anthracycline and cyclophosphamide

Purpose

To investigate whether palonosetron is better than granisetron in preventing chemotherapy‐induced nausea and vomiting (CINV) in a three‐drug combination with dexamethasone and fosaprepitant (Fos) in patients with breast cancer who are placed on anthracycline and cyclophosphamide (AC‐based regimen).

Patients and Methods

Chemo‐naive women with primary breast cancer were randomly administered either palonosetron 0.75 mg (day 1) or granisetron 1 mg (day 1) combined with dexamethasone (12 mg at day 1, 8 mg at day 2 and day 3) and Fos 150 mg (day 1) before receiving AC‐based regimen in a double‐blind study. The primary endpoint was the complete response (CR) rate of emesis in cycle 1 in the delayed phase. This was defined as neither vomiting nor rescue drug usage for emesis at >24‐120 hours after chemotherapy. Secondary endpoints were the CR in the acute/overall phase (0‐24/0‐120 hours, respectively, after chemotherapy), no nausea and vomiting, Patient‐Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO‐CTCAE), and safety.

Results

From December 2012 to October 2014, 326 patients were treated and evaluated (164/162 evaluable patients in granisetron/palonosetron arm, respectively). The CR during the delayed phase was 60.4% in the granisetron regimen and 62.3% in the palonosetron regimen. The CR during acute phase (73.2% vs 75.9%, respectively) and the CR during overall phase (54.9% in both regimens) were very identical. A significantly higher number of patients in the palonosetron arm were free from nausea during the delayed phase (28% vs 40.1%; P = .029). Adverse events were also identical, although infusion site reactions (ISR) were higher (20.3%‐23.3%) than preceding studies in both regimens.

Conclusion

In combination with dexamethasone and Fos, this study suggests that palonosetron is not better than granisetron in chemo‐naive patients with primary breast cancer receiving AC‐based regimen. Administration of Fos in peripheral veins after AC‐based regimen increased ISR.

Abstract GS1-09: Addition of S-1 to endocrine therapy in the post-operative adjuvant treatment of hormone receptor-positive and human epidermal growth factor receptor 2-negative primary breast cancer: A multicenter, open-label, phase 3 randomized trial (POTENT trial)

BACKGROUND: Although long-term prognostic outcomes of primary breast cancer (PBC) patients have been improved remarkably in recent years, the disease recurrence remains a serious problem. We have previously investigated a role for oral fluoropyrimidines in postoperative adjuvant treatments.In this study, we aimed to verify the usefulness of S-1 in combination with adjuvant endocrine therapy for PBC patients having luminal disease.

PATIENTS AND METHODS: This open-label, randomized, phase 3 trial was carried out in 139 centers in Japan. StageI-IIIPBC patients, who had hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negativestatus and intermediate or higher risk of recurrence were randomly assigned (1:1) to receive standard endocrine therapy alone (control arm) or endocrine therapy plus S-1 (S-1 arm). Recurrence risk assessment was performed using anatomical stage, pathological findings such as histologic grade, and centrally confirmed proliferative marker status. S-1 was administered postoperatively in combination with standard endocrine therapy. For patients who underwent multi-drug postoperative adjuvant or preoperative neoadjuvant chemotherapy, S-1 was administered following the multi-drug chemotherapy. Cases having no residual cancer in the breast and axillary node after the preoperative chemotherapy were excluded from this study. The S-1 dosage was chosen among 80 mg/day, 100 mg/day, and 120 mg/day according to the body surface area of each patient, and S-1 was administered for one year with a 2 weeks on/1 week off administration schedule. The primary endpoint was invasive disease-free survival (iDFS), defined as time from randomization to invasive disease recurrence, occurrence of second invasive cancer event, or death, and was analyzed on an intent-to-treat basis. Secondary endpoints included DFS, distant DFS, overall survival, and safety profile.

RESULTS: From Feb 2012 to Feb 2016, 1959 patients were enrolled and 1932 patients were included in the full analysis set (control arm, 973; S-1 arm, 959). The results of the prespecified interim analysis met the primary end point, and this trial was terminated early. Median follow-up was 51.4 months. S-1 significantly reduced invasive events; 153 iDFS events were reported in the control arm and 99 iDFS events were reported in the S-1 arm [hazard ratio, 0.63 (95%CI, 0.49-0.81); p-value, 0.0003]. The 5-year iDFS estimate was 81.5% in the control arm and 86.9% in the S-1 arm. Distant recurrence as the first disease event was observed in 6.8% of patients in the S-1 arm and in 9.5% of those in the control arm. The safety data in patients treated with S-1 was consistent with the known profile of S-1. The S-1 treatment was well tolerated and manageable.

CONCLUSIONS: It was concluded that the postoperative adjuvant use of an oralfluoropyrimidine S-1 significantly reduced iDFS events and improved 5-year iDFS estimate in PBC patients having HR-positive and HER2-negative disease, in the combination with standard endocrine therapy, with a feasible safety profile.

Funding: This study was funded by the Comprehensive Support Project (CSP) of the Public Health Research Foundation. The research fund was provided to CSP by Taiho Pharmaceutical Co., Ltd. This trial was conducted as a study of ‘Advanced Medical Care,’ the Ministry of Health, Labour and Welfare, Japan. JRCT ID: jRCTs051180057, UMIN000003969

Citation Format: Masakazu Toi, Shigeru Imoto, Takanori Ishida, Yoshinori Ito, Hiroji Iwata, Norikazu Masuda, Hirofumi Mukai, Shigehira Saji, Akira Shimizu, Takafumi Ikeda, Hironori Haga, Toshiaki Saeki, Kenjiro Aogi, Tomoharu Sugie, Takayuki Ueno, Takayuki Kinoshita, Yuichiro Kai, Masahiro Kitada, Yasuyuki Sato, Kenjiro Jimbo, Nobuaki Sato, Hiroshi Ishiguro, Masahiro Takada, Yasuo Ohashi, Shinji Ohno. Addition of S-1 to endocrine therapy in the post-operative adjuvant treatment of hormone receptor-positive and human epidermal growth factor receptor 2-negative primary breast cancer: A multicenter, open-label, phase 3 randomized trial (POTENT trial) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr GS1-09.

A population-based recurrence risk management study of patients with pT1 node-negative HER2+ breast cancer: a National Clinical Database study

Purpose

Recurrence risk management of patients with small (≤ 2 cm), node-negative, human epidermal growth factor receptor 2 (HER2)-positive breast cancer remains challenging. We studied the effects of adjuvant chemotherapy and/or trastuzumab and survival outcomes among these patients, using data from the population-based Japanese National Clinical Database (NCD).

Methods

We identified a cohort of 2736 breast cancer patients with HER2+ pT1N0 disease: 489 pT1a, 642 pT1b, and 1623 pT1c. The median observation period was 76 months, and the 5-year follow-up rate was 48.2%. The number of events was 212 for disease-free survival (DFS), 40 for breast cancer-specific survival, and 84 for overall survival (OS).

Results

There were 24.5% of pT1a, 51.9% of pT1b, and 63.3% of pT1c patients who were treated systemically after surgery. OS in pT1b (logrank test; p = 0.03) and DFS in pT1c (logrank test; p < 0.001) were significantly improved in treated compared with untreated patients. In the Cox proportional hazards model, treated patients had significantly longer OS than untreated patients in pT1b (hazard ratio (HR) 0.20) and pT1c (HR 0.54) groups. Estrogen receptor-negative tumors was also a significant predictor of survival in pT1c (HR 2.01) but not pT1ab patients. Furthermore, HR was greater in patients aged ≤ 35 years (3.18) compared to that in patients aged 50–69 years in the pT1b group.

Conclusions

NCD data revealed that systemic treatment improved OS in pT1bc but not in pT1a node-negative HER2+ breast cancer patients. Future observational research using big-sized data is expected to play an important role in optimizing treatment for patients with early-stage breast cancer.

Electronic supplementary material

The online version of this article (10.1007/s10549-019-05413-7) contains supplementary material, which is available to authorized users.

Risk Factors for Skin Flap Necrosis in Breast Cancer Patients Treated with Mastectomy Followed by Immediate Breast Reconstruction

BACKGROUND

Skin-sparing mastectomy (SSM) and nipple-sparing mastectomy (NSM) are the standard techniques for achieving a cosmetic outcome, but necrosis of a cutaneous flap including the nipple-areolar complex (NAC) is a serious complication. To analyze the risk factors for skin flap necrosis, we retrospectively evaluated a clinical database of breast cancer patients treated with mastectomy followed by immediate breast reconstruction.

METHODS

Four hundred and twelve cases were consecutively recorded between 2006 and 2016. Body weight (BW), body mass index (BMI), distance from NAC to referent tumor, distance from overlying skin to the tumor and weight of breast resection (WBR) as measured in the operating theater were included in the statistical analysis.

RESULTS

NSM, SSM and total mastectomy were performed in 123 (30%), 96 (23%) and 193 cases (47%), respectively. A tissue expander was used in 379 cases (92%), a silicone implant in 8 (2%) and autologous breast reconstruction in 25 (6%). Skin flap necrosis was found in 7% of all cases and NAC necrosis in 13% of NSM cases. In a univariate analysis, BW, NSM and WBR were risk factors for skin flap necrosis, and BW, BMI and WBR were risk factors for NAC necrosis. In a multivariate analysis, NSM and WBR remained significant risk factors for skin flap necrosis, and WBR was a significant risk factor for NAC necrosis.

CONCLUSIONS

WBR is an important risk factor for skin flap necrosis. Especially, NAC necrosis should be considered for patients with large-volume breasts who undergo NSM and immediate breast reconstruction.

Relation between dexamethasone (DEX) usage, preventive trimetprim/sulfametoxazole (ST), and pneumocystis pneumonia (PCP) for patients with breast cancer receiving dose-dense AC followed by dose-dense paclitaxel (ddAC-ddP): Preplanned analysis of WJOG9016B

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Background: PCP is rare complication of ddAC-ddP. DEX is plausible risk factor for PCP. Dose and duration of DEX against CINV is changing over time as other anti-emetic drugs (5HT3 RA, NK1 RA, and olanzapin) became available. Then DEX usage varies widely in each hospitals. ASCO/IDSA guideline recommends preventive ST for patients receiving 20 mg or more predonisone equivalents daily for more than one month, although evidence is lacking in patients receiving ddAC-ddP. This study is to investigate relation between DEX usage, preventive ST, and risk of PCP for patients receiving ddAC-ddP. Methods: This study is preplanned analysis of WJOG9016B (UMIN000024992) which investigated relative dose intensity of ddAC-ddP supported by 3.6 mg (approved dose in Japan) of pegfilgrastim. Eligible pts were HER2 negative PBC with stage I to IIIc, going to start ddAC-ddP and younger than 65 y.o.. DEX usage and preventive ST usage were discrete to treating physicians. Results: From Jan. 2017 to Jan. 2018, 92 pts were registered and 91 pts were in the FAS set, because one patients turned out be ineligible after registration. All patients received DEX for prevention of delayed CINV. Median total dose of DEX during ddAC was 112 mg (range; 80 to 212 mg), which was equal to 13.3 mg (9.52 mg–24.76 mg) predonisone equivalents daily. Only five of them (5.4%) received more than 20 mg predonisone equivalents daily. Twenty patients received preventive ST. Three patients developed PCP. None of them with preventive ST developed PCP (0%), whereas three of patients without ST developed PCP (4.2%). These three patients received total DEX dose during ddAC at 80 mg, 112 mg, and 112 mg, respectively. Conclusions: ST was highly effective for PCP prevention for patients receiving ddAC-ddP, if DEX used against delayed CINV. Without ST prevention, the risk of PCP was 4.2 %, which was higher than threshold (3.5%) proposed in ASCO/ IDSA guidelines. The threshold of steroid dose leading to the risk of PCP might be lower than 20 mg or more predonisone equivalents daily in patients receiving ddAC-ddP. Clinical trial information: UMIN000024992.

Progesterone receptor expression in proliferating cancer cells of hormone-receptor-positive breast cancer

Breast cancer has been suggested to have two distinct driving mechanisms: the hormone receptor and the growth factor receptor pathways. We hypothesized that each driving system produces a different expression pattern of estrogen-regulated genes, such as progesterone receptor, in proliferating cells. Progesterone receptor and Ki67 expressions were assessed by dual-fluorescence immunohistochemistry in estrogen-receptor-positive breast cancer tissues. Two distinct proliferating cell populations were observed: progesterone-receptor-positive and progesterone-receptor-negative. In the training cohort, tissues with progesterone-receptor-positive proliferating cells were associated with lower grade and better disease-free survival (p = 0.0055 and 0.0026, respectively). These associations were confirmed in the validation cohort from the neoadjuvant endocrine trial JFMC34 (p = 0.033 and 0.0003, respectively). In the validation cohort, patients with progesterone-receptor-positive proliferating cells responded better to endocrine therapy and had a lower Oncotype DX Recurrence Score. In the multivariate analysis, progesterone receptor status of proliferating cells, but not progesterone receptor or Ki67 alone, was an independent predictor of disease-free survival in both cohorts (p = 0.0043 and 0.0026). In conclusion, the progesterone receptor status of proliferating cancer cells was associated with histological grade and Recurrence Score, and a potent prognostic factor in estrogen-receptor-positive breast cancers. Results suggest that different driving systems generate different expression patterns of progesterone receptor in proliferating cancer cells. Further studies are warranted to validate the findings.

Abstract OT2-05-02: International retrospective cohort study of locoregional and systemic therapy in oligometastatic breast cancer (OLIGO-BC1)

Breast cancer (BC) is so-called “systemic disease”, because disseminated cancer cells in bone marrow and blood are detected even in early BC patients. Despite adjuvant therapy and postoperative radiation therapy, patients with triple negative BC and Luminal B-like BC often relapse early and systemic therapy is the only way to control disease progression. On the other hand, some BC patients relapse several years later. In such patients, oligometastases are occasionally diagnosed, because metastatic cancer cells are slowly growing and indolent. Oligometastatic BC is defined as low volume metastatic disease with limited number and size of metastatic lesions (up to five and not necessarily in the same organ). This definition is proposed in the Advanced Breast Cancer guidelines that are developed as a joint effort from European School of Oncology and European Society of Medical Oncology. Several retrospective studies demonstrated survival benefit of locoregional therapy in addition to systemic therapy. Locoregional therapy consisted of surgical resection, radiation therapy, ablation therapy, etc. However, it remains unclear about survival benefit of combined therapy in oligometastatic BC. To improve the standard of cancer treatment through the cooperate studies on more effective therapeutic strategies based on drugs, surgery and/or radiotherapy, Federation of Asian Clinical Oncology (FACO) was established in 2012 by Chinese Society of Clinical Oncology (CSCO), Korean Society of Medical Oncology (KSMO) and Japan Society of Clinical Oncology (JSCO). Thus, FACO conducted a retrospective cohort study on oligometastatic BC. The primary endpoint is to compare the estimated 5-year overall survival (OS) of oligometastatic BC patients treated with combined therapy and systemic therapy alone. To hypothesize that combined therapy has more advantage of OS in oligometastatic BC, the 5-year OS rates are expected to be 50% and 40%, respectively. The estimated sample size is calculated to be the number of 698 cases (349 cases in each group) needed to prove the superiority of survival with a two-sided type I error rate of 5% and a statistical power of 80%. Case registry opened in February 2018 and will close in January 2019. We planned to register 700 cases, i.e., 234 cases each from investigators of CSCO, KSMO and JSCO. Update information will be discussed.

Citation Format: Imoto S, Futamura M, Toi M, Fujiwara Y, Ueno T, Im Y-H, Im S-A, Ahn SG, Lee JE, Park YH, Wang K, Kitagawa Y, Nishiyama M. International retrospective cohort study of locoregional and systemic therapy in oligometastatic breast cancer (OLIGO-BC1) [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 OT2-05-02.

Abstract OT2-01-01: Observational study of axilla treatment for breast cancer patients with 1 to 3 positive micrometastases or macrometastases in sentinel lymph nodes

[Background] Axilla surgery in node-positive breast cancer is dramatically changing from axillary lymph node dissection (ALND) to sentinel node biopsy (SNB). From the results of ACOSOG Z0011, IBCSG23-01 and AMAROS trials, adjuvant therapy and regional node irradiation could reduce regional lymph node recurrence for sentinel node-positive breast cancer patients. However, optimal indication of SNB alone remains uncertain. Trial design: To evaluate the outcome of sentinel node-positive breast cancer patients, the Japanese Society for Sentinel Node Navigation Surgery (SNNS) conducted a prospective cohort study in 2013 (UMIN000011782, Jpn J Clin Oncol, p.876-9, 2014). [Eligibility criteria] For eligible patients, SNB was performed or scheduled after 1 January 2012. Then 1 to 3 positive micrometastases or macrometastases in sentinel lymph nodes are confirmed by histological or molecular diagnosis. Primary chemotherapy before or after SNB is also acceptable for registration. [Specific aims] The primary endpoint is the 5-year recurrence rate of regional lymph node in patients treated with SNB alone. The secondary endpoint is the 5-year overall survival rate of this cohort. Patients treated with SNB followed by ALND are also registered simultaneously to compare the prognosis. The propensity score matching (PSM) is used to make the distributions of baseline risk factors comparable. [Statistical method] Based on an estimated recurrence rate of 5% at 5 years among patients treated with SNB alone, 240 patients are needed to give a 80% power to reject the null hypothesis that the recurrence rate is 10% with a one-sided type I error rate of 2.5%. If we consider that some patients will be lost to follow-up or become ineligible, a total of 250 patients will be needed to comprise the sample. [Present accrual] Eight hundred and eighty patients who underwent SNB alone or SNB followed by ALND were registered from 27 participating institutes between 2013 and 2016. Data cleaning is being performed. Patient's background and PSM will be reported.

Citation Format: Imoto S, Saito Oba M, Masuda N, Nagashima T, Wada N, Takashima T, Kitada M, Kawada M, Hayashida T, Taguchi T, Aihara T, Miura D, Toh U, Yoshida M, Sugae S, Yoneyama K, Matsumoto H, Jinno H, Sakamoto J. Observational study of axilla treatment for breast cancer patients with 1 to 3 positive micrometastases or macrometastases in 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 OT2-01-01.

Phase II study on radiofrequency ablation in stage 0 and I breast cancer without extensive intraductal components

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Background: We reported about a multi-center registration study on radiofrequency ablation (RFA) in early breast cancer (BC) (ASCO2012 #1119). Although various devices and ablation procedure were used, 5-year’s recurrence-free survival was 96% in 425 cases of T1BC treated with RFA alone. To validate complete pathological ablation in BC, we started a non-randomized phase II study in 2013 (UMIN000013836). Methods: Unilateral BC patients with stage 0 (TisN0M0) or I (T1N0M0 or T1N1miM0) were eligible. Tumor diameter of 2cm or less should be diagnosed by ultrasound and MR mammography. RFA was performed by Cool-tip RF ablation system (Covidien, USA). One month later, ablated tissue was collected by core needle biopsy or vacuum-assisted breast biopsy. Cell viability was determined by central review of independent pathologists using tumor specimens stained with hematoxylin–eosin and nicotinamide adenine dinucleotide (NADH) diaphorase. In case of complete ablation, breast irradiation and adjuvant therapy was planned. In case of incomplete ablation, partial mastectomy was recommended. The primary endpoint is complete ablation rate. The secondary endpoints are breast deformity after RFA, relapse-free survival and overall survival for 10 years. Two-step design consisting of 9 cases at 1st step and 20 cases at 2nd step was used for statistical evaluation. We expected complete ablation rate of 95% and 29 cases were needed to reject the null hypothesis that complete ablation rate would be less than 80% at lower threshold. Thus, 32 cases were required. Results: Thirty-six patients were enrolled between February 2013 and May 2016. The mean tumor size was 1.3 cm measured by MR mammography. Two patients were ineligible because of macrometastasis in a sentinel node. Of 34 eligible patients, one patient had viable cancer cells with NADH diaphorase staining in ablated specimens. Finally, complete ablation rate was 97%. As of January 2017, one patient, who refused adjuvant therapy and breast irradiation, had in-breast tumor recurrence adjacent to previously ablated lesion. Conclusions: Long-term follow-up should be needed, but RFA in early BC is a promising strategy instead of breast-conserving surgery. Clinical trial information: UMIN000013836.

Abstract 4138: Immunological profile of metastatic or recurrent breast cancer patients

Background: We previously reported about immune suppression in breast cancer patients at this meeting. In brief, tumor tissue specimens and peripheral blood mononuclear cells (PBMC) were analyzed in 50 early or advanced breast cancer (BC) patients. To compare between 38 early and 12 advanced BC cases, CD163-positive tumor cells and CCR4-positive tumor cells were detected more frequently in advanced cases than in early cases. Regulatory T (Treg) cells in PBMC significantly increased in percentage of the population in 37 BC patients than in 21 healthy volunteers (AACR 2011). In addition, several cytokines were examined in that cohort and plasma IL-17A had significantly higher levels in early BC than in advanced BC (AACR 2013). Then, we examined their prognosis and immunological profile.

Patients and methods: Treg cells were examined by counting CD4+CD25highCD127low/-cells in PBMC with flow cytometry analysis. Immunohistochemical evaluation of tumor specimens was performed with monoclonal antibodies of HLA-ABC and DR, CD56, CD68, CD83, CD163 and CCR4. The number of stained cells was analyzed using a semiquantitative ordinal scale ranging from 0 to 3 (0, +/-, ++, +++). Human IL-2, IL-4, IL-6, IL-10, TNF, INFγ and IL-17A were measured using cytometric beads array system. Most patients received chemotherapy, hormonal therapy, and/or anti-HER2 therapy on the basis of intrinsic subtype and breast irradiation after breast-conserving surgery.

Results and discussions: At the median follow-up of 7 years after blood sample collection, only 2 operable patients relapsed and 3 patients including 2 cases of stage IV died of disease. Of 5 cases of stage IV or recurrent BC, CD163 and/or CCR4 were strongly stained positive in tumor cells. There were significant differences of staining intensity in CD163 and CCR4-positive tumor cells between those cases and the rest 45 cases (p&lt;0.01 at Chi-square test). However, other immune cell profiles, Treg cells in PBMC and cytokines in plasma had no trend between them. Several reports demonstrated that cancer patients with CD163-positive tumor-infiltrating macrophages and CD163-positive tumor cells had poor prognosis due to tumor-associated macrophage. Phenotypic macrophage traits in cancer cells, like CD163 expression, may be explained by heterotypic cell fusion between monocytes/macrophages and cancer cells.

Conclusion: Targeted therapy against M2 macrophage or CCR4 is considered as a promising strategy of advanced breast cancer.

Citation Format: Shigeru Imoto, Takayuki Ueno, Hirotsugu Isaka, Hiroki Ito, Kaisuke Miyamoto, Tomohiro Chiba, Hiroshi Kamma. Immunological profile of metastatic or recurrent breast cancer patients. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4138.

Abstract 3484: Analysis of in situ expression of hormone receptors and proliferation marker at a single cell level in breast cancer tissues

Background: Hormone receptors and proliferation markers are critical parameters for treatment selection of breast cancer patients. The expression of different parameters are currently assessed separately in different tissue sections but it is unclear how different parameters are co-expressed in a single cell in breast cancer tissues.

Samples and Methods: Breast cancer tissues from fifty-one patients with ER-positive HER2-negative breast cancer were analyzed. Expressions of ER and PgR were assessed in association with Ki67 using dual fluorescence immunohistochemistry with specific antibodies: SP-1 (abcam, Tokyo), 1E2 (Roche Diagnostics GmBH, Germany), and MIB1 (Dako Japan, Tokyo), respectively. More than 500 cancer cells were assessed in each tissue. Expression levels of each marker in a single cell were semi-quantitatively assessed by MetaMorph image analyzer (Molecular Devices Japan, Tokyo). All statistical analyses were performed using JMP ver.8.01 (SAS Institute Japan, Tokyo).

Results: To validate the system, Ki67 LI in breast cancer tissues were compared between this system and the regular DAB system. The two systems showed a good concordance (p &lt; 0.0001). All cancer tissues expressed ER. There were two distinct populations among Ki67-positive proliferating cells according to PgR expression status: PgR-positive proliferating cells and PgR-negative proliferating cells. Since cell proliferation is regulated in cancer cells by at least two different drivers including hormone receptor and growth factor, it is conceivable that these two populations depend on different driving systems. Indeed, tissues with dominantly PgR-positive proliferating cells showed mostly histological grade 1 (15/20, 75%), while most of tissues with PgR-negative proliferating cells showed grade 2 and 3 (22/31, 71%) (p = 0.0025 by chi square test). Moreover, the multivariate analysis using the ordered logistic regression analysis showed that PgR status in proliferating cells is an independent factor associated with histological grade (p = 0.003) while PgR expression rate and Ki67 LI were not (p = 0.3 and 0.25, respectively).

Conclusion: PgR status in Ki67-positive proliferating cells is associated with histological grade in ER positive HER2-negative breast cancers. Our results suggest that different driving systems give different expression patterns of PgR and Ki67 at a single cell level, which may distinguish between luminal A and luminal B cancers.

Citation Format: Takayuki Ueno, Hirotsugu Isaka, Hiroki Itoh, Kaisuke Miyamoto, Manami Kitamura, Shigeru Imoto. Analysis of in situ expression of hormone receptors and proliferation marker at a single cell level in breast cancer tissues. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3484.

The hnRNP-Htt axis regulates necrotic cell death induced by transcriptional repression through impaired RNA splicing

In this study, we identify signaling network of necrotic cell death induced by transcriptional repression (TRIAD) by α-amanitin (AMA), the selective RNA polymerase II inhibitor, as a model of neurodegenerative cell death. We performed genetic screen of a knockdown (KD) fly library by measuring the ratio of transformation from pupa to larva (PL ratio) under TRIAD, and selected the cell death-promoting genes. Systems biology analysis of the positive genes mapped on protein-protein interaction databases predicted the signaling network of TRIAD and the core pathway including heterogeneous nuclear ribonucleoproteins (hnRNPs) and huntingtin (Htt). RNA sequencing revealed that AMA impaired transcription and RNA splicing of Htt, which is known as an endoplasmic reticulum (ER)-stabilizing molecule. The impairment in RNA splicing and PL ratio was rescued by overexpresion of hnRNP that had been also affected by transcriptional repression. Fly genetics with suppressor or expresser of Htt and hnRNP worsened or ameliorated the decreased PL ratio by AMA, respectively. Collectively, these results suggested involvement of RNA splicing and a regulatory role of the hnRNP-Htt axis in the process of the transcriptional repression-induced necrosis.

Clinical significance of the expression of autophagy-associated marker, beclin 1, in breast cancer patients who received neoadjuvant endocrine therapy

Background

Neoadjuvant endocrine therapy (NAE) has been employed to improve surgical outcomes for hormone receptor-positive breast cancers in postmenopausal women. Endocrine responsiveness is estimated by expressions of hormone receptors, but its heterogeneity has been recognized. Autophagy is an evolutionally conserved process associated with cell survival and cell death and has been implicated in cancer treatment.

Methods

In order to examine the possible association between autophagy and response to endocrine therapy, we evaluated the status of autophagy-associated markers, beclin 1 and LC3, and apoptosis-associated markers, TUNEL and M30, in pre- and post-treatment specimens from 71 patients in a multicenter prospective study of neoadjuvant exemestane (JFMC34-0601).

Results

Immunoreactivity of the autophagy-associated markers, beclin 1 and LC3, in carcinoma cells increased in 14 % and 52 % of the patients, respectively, following the exemestane treatment. These increases were statistically significant (beclin 1, p = 0.016, N = 49; LC3, p < 0.0001, N = 33). The status of M30 immunoreactivity decreased (p = 0.008, N = 47) and TUNEL remained unchanged (N = 53). In addition, tumors with pre-treatment stromal beclin 1 immunoreactivity revealed poor clinical and pathological responses compared with those without stromal beclin 1 immunoreactivity (25 % vs 67 % for clinical response, p = 0.011, N = 51; 0 % vs 41 % for pathological response, p = 0.0081, N = 49). Tumors with positive pre-treatment stromal beclin 1 had a higher baseline Ki-67 labeling index (both hot spot and overall average) than those without (p = 0.042 and 0.0075, respectively, N = 53). Results of logistic regression analyses revealed that stromal beclin 1 was a predictor for clinical and pathological responses while ER, PR, Ki-67, and stromal LC3 expressions were not.

Conclusions

Results of our present study demonstrated that beclin 1 and LC3 immunoreactivity increased in carcinoma cells following exemestane treatment and that the status of pre-treatment stromal beclin 1 is associated with higher carcinoma cell proliferation and poor clinical and pathological responses to NAE.

Trial registration

UMIN C000000345 (2006/03/06)

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2270-9) contains supplementary material, which is available to authorized users.

Abstract P3-13-07: Radiofrequency ablation (RFA) is a promising treatment option for primary breast cancer: Experience in 386 Japanese breast cancer patients

Background. Radiofrequency ablation (RFA) is used for the treatment of various solid tumors. Several small experiences have reported as a primary treatment for breast cancer using RFA. However, the clinical benefits remain uncertain. We retrospectively studied 386 patients and analyzed their RFA-related complications and outcomes.

Methods. A clinical database was constructed from 10 institutions. RFA was performed using an electrical generator connected to a single cooled-tip electrode or multiple electrodes. Adjuvant systemic therapy and whole breast radiation were administered according to the clinicopathological background of each patient. Follow-up periods ranged from 1 to 90 months (mean 45.4 months). RFA-related complications and risk factors for in-breast recurrence after RFA were evaluated. Variables evaluated included patient characteristics, pre- and post-operative imaging modalities, tissue sampling modalities, and RFA-related factors.

Results. Skin burns were observed in 7 patients (1.8 %) and RFA-induced damage to the nipple-areolar complex in 7 patients (1.8 %). Persistent induration of the breast after RFA was observed in 137 patients (35.5 %). Eleven patients (2.8 %) developed in-breast recurrence. In-breast recurrence was more frequent in patients with tumor size &gt;2.0 cm, ER-negative tumor, HER2-positive tumor, positive nodes, no breast irradiation and adjuvant chemotherapy.

Conclusions. Skin burns were a major problem after RFA, but the frequency of burns was relatively low. Breast induration was also developed, but it did not bring harmful effect to the patients with this complication. We conclude that RFA is a promising treatment option for solid T1 breast cancer without malignant potential.

Citation Format: Takahashi M, Ito T, Oura S, Nagamine S, Yamamoto N, Yamamichi N, Earashi M, Doihara H, Imoto S, Mitsuyama S, Akazawa K. Radiofrequency ablation (RFA) is a promising treatment option for primary breast cancer: Experience in 386 Japanese breast cancer patients. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-13-07.

One-step nucleic acid amplification assay for intraoperative prediction of advanced axillary lymph node metastases in breast cancer patients with sentinel lymph node metastasis

The one-step nucleic acid amplification (OSNA) assay is used to semiquantitatively measure the cytokeratin (CK)19 mRNA copy numbers of each sentinel lymph node (SLN) in breast cancer patients. The aim of the present study was to evaluate whether the diagnosis of ≥4 LN metastases is possible using the OSNA assay intraoperatively. Between May, 2010 and December, 2014, a total of 134 patients who underwent axillary lymph node dissection (ALND) of positive SLNs were analyzed. The total tumor load (TTL) was defined as the total CK19 mRNA copies of all positive SLNs. The correlation between TTL and ≥4 LN metastases was evaluated. Of the 134 patients, 31 (23.1%) had ≥4 LN metastases. TTL ≥5.4×10⁴ copies/µl evaluated by receiver operator characteristic curve analysis was examined along with other clinicopathological variables. In the multivariate analysis, only TTL ≥5.4×10⁴ copies/µl was correlated with ≥4 LN metastases (odds ratio = 2.95, 95% confidence interval: 1.17-7.97, P=0.022). Therefore, TTL assessed by the OSNA assay has the potential to be a predictor of ≥4 LN metastases and it may be useful for the selection of patients with positive SLNs in whom ALND may be safely omitted.

Taxanes versus S-1 as the first-line chemotherapy for metastatic breast cancer (SELECT BC): an open-label, non-inferiority, randomised phase 3 trial

BACKGROUND

Oral fluoropyrimidines are used for the first-line treatment of metastatic breast cancer to avoid severe adverse effects, although firm supporting evidence is lacking. We aimed to establish whether S-1 is non-inferior to taxanes in this setting.

METHODS

We did an open-label, non-inferiority, phase 3 trial at 154 hospitals in Japan. We enrolled individuals who had HER2-negative metastatic breast cancer who had received no chemotherapy for advanced disease, and who were resistant to endocrine treatment. Patients were randomly assigned (1:1) either to taxane (docetaxel 60-75 mg/m(2) at intervals of 3-4 weeks; paclitaxel 80-100 mg/m(2) weekly for 3 of 4 weeks; or paclitaxel 175 mg/m(2) at intervals of 3-4 weeks) or to S-1 (40-60 mg twice daily for 28 consecutive days, followed by a 14-day break). Randomisation was done centrally with the minimisation method, with stratification by institution, liver metastasis, oestrogen and progesterone receptor status, previous treatment with taxanes or oral fluorouracil, and time from surgery to recurrence. The primary endpoint was overall survival, with a prespecified non-inferiority margin of 1·333 for the hazard ratio (HR). The primary efficacy analysis was done in the full analysis set, which consisted of all patients who took at least one study treatment and who had all data after randomisation. This trial is registered with the University Hospital Medical Information Network, Japan (protocol ID C000000416).

FINDINGS

Between Oct 27, 2006, and July 30, 2010, we enrolled 618 patients (309 assigned to taxane; 309 assigned to S-1). The full analysis set consisted of 286 patients in the taxane group and 306 in the S-1 group. Median follow-up was 34·6 months (IQR 17·9-44·4). Median overall survival was 35·0 months (95% CI 31·1-39·0) in the S-1 group and 37·2 months (33·0-40·1) in the taxane group (HR 1·05 [95% CI 0·86-1·27]; pnon-inferiority=0·015). The most common grade 3 or worse adverse events were neutropenia (20 [7%] of 307 patients in the S-1 group vs nine [3%] of 290 patients in the taxane group), fatigue (ten [3%] vs 12 [4%]), and oedema (one [<1%] vs 12 [4%]). Treatment-related deaths were reported in two patients in the taxane group.

INTERPRETATION

S-1 is non-inferior to taxane with respect to overall survival as a first-line treatment for metastatic breast cancer. S-1 should be considered a new option for first-line chemotherapy for patients with HER2-negative metastatic breast cancer.

FUNDING

Comprehensive Support Project for Oncology Research of the Public Health Research Foundation, Japan; Taiho.