Hirohito Seki

Primary systemic chemotherapy of breast cancer: indication and predictive factors

Primary systemic chemotherapy has become a standard of care for operable breast cancer patients who are candidates for adjuvant chemotherapy. Induction of pathological complete response (pCR) is one of the main goals of primary systemic chemotherapy because patients with pCR have shown a better prognosis. The definition of pCR has varied across clinical trials. It would be ideal for all researchers to use the same terminology in describing pathologic response. Identification of accurate predictive factors of pCR to primary systemic chemotherapy is urgent, because patients with a low chance of pCR and clinical response should be spared unnecessary toxicity. Early response to primary systemic chemotherapy might be correlated with a high probability of a pCR. Therefore, evaluation of early response is useful to avoid unnecessary toxicity without potential benefit from chemotherapy.

Weekly nab-paclitaxel followed by FEC in patients with operable breast cancer: Phase II study.

138 Background: Nanoparticle albumin-bound paclitaxel (nab-PTX) has a high transitivity into tumor tissue compared to solvent-based paclitaxel (sb-PTX). In a phase III study in patients with metastatic breast cancer, nab-PTX demonstrated nearly double the response rate and significantly longer time to tumor progression than paclitaxel. However, the current problems are that nab-PTX is a higher rate of discontinuation and sensory neuropathy than sb-PTX. We sought to evaluate the efficacy and safety of nab-PTX followed by FEC. METHODS In this study, patients were received 4 cycles of nab-PTX (80 mg/m2) q1w (days 1, 8, and 15 of each 4-week cycle) followed by 4 cycles of FEC q3w. The primary endpoint was pCR rate (ypT0/is ypN0). The secondary endpoints included clinical response rate, disease-free survival, breast-conserving surgery rate, and safety. RESULTS Forty patients were enrolled; the median age was 53 (range 33-81), postmenopausal women were 62.5%. ER positivity, PgR positivity and HER2 positivity were 62.5%, 52.5% and 37.5%, respectively. Clinical stage for I, II and III were 30%, 62.5% and 7.5%, respectively. The pCR rate (ypT0/is ypN0) was 40% (16/40). In the subtype subset, pCR rates were Luminal A 20% (1/5), Luminal B (HER2 negative) 15.4% (2/13), Luminal B (HER2 positive) 60% (6/10), HER2 enrich 80% (4/5) and TNBC 42.9% (3/7). The breast-conserving surgery rate was 77.5% (31/40). The clinical response rates were cCR 20.0% (8/40), cPR 52.5% (21/40), cSD 25% (10/40) and cPD 2.5% (1/40) after 4 cycles of nab-PTX, cCR 32.5% (13/40), cPR 42.5% (17/40), cSD 20% (8/40) and cPD 5% (2/40) after nab-PTX followed by FEC. Ninety-eight percent patients completed 4 cycles of planned protocol dose of nab-PTX and 62.5% completed FEC. The Grade3/4 hematologic toxicity of nab-PTX was only neutropenia 2.5%. Grade1/2 non-hematologic toxicity were neuropathy 12.5%, arthralgia 7.5% and myalgia 7.5%. Grade3/4 non-hematologic toxicity was no reported. CONCLUSIONS This is the first study to evaluate weekly nab-PTX (80 mg/m2) followed by FEC for operable breast cancer. Our results demonstrated that weekly nab-PTX (80 mg/m2) followed by FEC was well-tolerated and resulted in increased pCR rate than reported data of nab-PTX. CLINICAL TRIAL INFORMATION UMIN000011048.

Thymidylate synthase expression as a predictive factor for response and progression-free survival in metastatic breast cancer patients.

132 Background: S-1, an oral fluoropyrimidine formulation that combines tegafur, 5-chloro-2,4-dihydroxypryidine, and potassium oxonate in a molar ratio of 1:0.4:1 has been widely used against solid cancers including gastric, colorectal, pancreatic, lung and breast cancer. In a phase II study, the response rate (RR) was 41.7% and the median survival was 872 days among taxane-pretreated patients with metastatic breast cancer (MBC). However, the predictive factor of S-1 in patients with MBC has not been determined yet. The purpose of this study is to investigate the correlation between 5-FU-related enzyme and clinical efficacy of S-1 in patients with MBC. METHODS Forty-eight patients with MBC were treated with S-1 twice daily at a dose of 80 mg/m2 for 4 weeks, followed by a 2-week rest interval. Laser-captured microdissection was performed from the formalin-fixed, paraffin-embedded tumor sections at surgery and the expression of 5-FU-related enzyme including thymidylate synthase (TS), thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD) was evaluated by RT-PCR. RESULTS The median age was 58 years. ER, PgR, HER2 was positive in 57, 28, and 14% of the entire patients, respectively. The median number of pretreated chemotherapy regimens was 2 (range 0-6). The sites of metastatic disease were the viceral in 25 patients, bone in 9 patients and soft tissue in 17 patients. The overall response rate (RR) was 22.9% (11/48) and clinical benefit rate was 41.7% (20/48). The median time to tumor progresssion (TTP) was 14.3 months (range 6.0 - 22.7). ER, PgR and HER2 status was not significantly correlated with RR. TS expression was significantly associated with clinical efficacy of S-1. Moreover, it is notable that triple negative breast cancer (TNBC) revealed lower TS expression than luminal type (TNBC vs luminal type = 80% (8/10) vs 36.4% (4/11), P= 0.054, OR 0.143, 95% CI 0.020-1.032). According to the correlation between metastatic sites and RR, better RR was noted for soft tissue metastases (soft tissue vs visceral = 25% (5/20) vs 84% (5/6), OR 15.0 (95%CI 1.40-161.05). CONCLUSIONS This study demonstrated that TS is a significant predicitve factor of S-1 in patients with MBC.

Abstract P4-09-08: HOXB9, a gene promoting tumor angiogenesis and proliferation, is significantly associated with poor clincal outcomes in ER-positive breast cancer patients

Background: Studies have suggested that HOXB9 expression in breast cancer cells promotes cellular invasiveness, metastatic ability, and tumor neovascularization in the surrounding tissue in in vitro and in vivo assays. These findings imply that HOXB9 overexpression may alter tumor-specific cell fates and the tumor stromal microenvironment, contributing to breast cancer progression (Hayashida et al., PNAS 2010). We previously reported that clinical outcomes were significantly decreased in HOXB9-positive patients (Seki et al., Ann Surg Oncol. 2012). In this study, it was demonstrated that HER2 type and basal-like breast cancers were more associated with HOXB9 positivity than the luminal type. Therefore, it is required to identify more detail clinicopathological features most likely to be associated with HOXB9 overexpression. We investigated the correlation between HOXB9 overexpression and clinicopathological variables, and clinical outcomes in estrogen receptor (ER)-positive breast cancer patients. Patients and methods: A consecutive series of 118 ER-positive breast cancer patients who underwent surgical treatment were examined. HOXB9 expression was analyzed immunohistochemically using the anti-human HOXB9 polyclonal antibody. Immunostaining of Ki-67 and CD31 were also performed to evaluate tumor proliferation and angiogenesis. Results: The median age was 59 years and median observation period was 62 months. Of 118 tumor specimens immunostained for HOXB9, 49 specimens (41.5%) were positive staining. Univariate logistic regression revealed high nuclear grade (p Conclusions: Our results suggest that HOXB9 expression promoting the cellular proliferation and the angiogenesis in tumor microenvironment is a significant prognostic factor for clinical outcomes in ER-positive breast cancer patients. Further study might help to determine the application of anti-angiogenic therapy for metastatic ER-positive breast cancer patients. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-09-08.

HOXB9, a gene promoting tumor angiogenesis and proliferation, as a prognostic factor in breast cancer.

33 Background: We demonstrated that HOXB9, a member of homeobox genes, expression promoted tumor neovascularization and metastasis in vitro and in vivo assay. These findings imply that overexpression of HOXB9 contributes to tumor progression through activation of signaling pathways that alter both tumor-specific cell fates and tumor-stromal microenvironment, leading to increased invasion and metastasis. (Hayashida et al., PNAS 2010) We sought to determine whether these results could be extended to the clinical application. In this study, we evaluated the correlation between HOXB9 expression, clinical outcomes, and the clinicopathological variables in breast cancer patients, and the contribution of HOXB9 expression to tumor cell proliferation and angiogenesis. METHODS A consecutive series of 141 patients with invasive ductal carcinoma who underwent surgical treatment were examined. HOXB9 protein expression was analyzed immunohistochemically using the anti-human HOXB9 polyclonal antibody. Immunostaining of Ki-67, CD31, and CD34 were performed to evaluate the association of proliferation and tumor angiogenesis with HOXB9 expression. RESULTS Of 141 tumor specimens immunostained for HOXB9, 69 specimens (48.9%) were positive staining. Univariate logistic regression revealed ER and PgR negativity, HER2 positivity, high nuclear grade, and large pathological tumor size as significant variables associated with HOXB9 expression. Moreover, 12 (92.3%) out of 13 triple negative breast cancer showed HOXB9 expression. The disease-free survival (DFS) and the overall survival were significantly different between the HOXB9 positive and negative group; HR=20.714, p=0.001, HR 9.206, p=0.003, respectively. A Multivariate analysis indicated that HOXB9 expression was the only independent prognostic factor for DFS (HR=15.532, p=0.009). In subgroup analysis, HOXB9 positive tumors showed a significant increase in the number of vasculature and the Ki-67 ratio in comparison with HOXB9 negative. CONCLUSIONS Our results suggest that HOXB9 expression promoting the tumor proliferation and the angiogenesis is a significant prognostic factor in breast cancer.

The relationship of HOXB9 expression promoting tumor cell proliferation and angiogenesis to clinical outcomes of patients with breast cancer.

10546 Background: Recently, we reported that HOXB9, a member of homeobox genes, expression promoted tumor neovascularization and metastasis in in vitro and in vivo asssay. These findings imply that overexpression of HOXB9 contributes to tumor progression through activation of signaling pathways that alter both tumor-specific cell fates and tumor-stromal microenvironment. (Hayashida et al., PNAS 2010) We sought to determine whether these results could be extended to the clinical application. In this study, we evaluated the correlation between HOXB9 expression, clinical outcomes, and the clinicopathological variables in breast cancer patients, and the contribution of HOXB9 expression to tumor cell proliferation and angiogenesis. METHODS A consecutive series of 141 patients with invasive ductal carcinoma who underwent surgical treatment from January 2004 to January 2005 were examined. HOXB9 protein expression was analyzed immunohistochemically using the anti-human HOXB9 polyclonal antibody. Immunostaining of Ki-67, CD31, and CD34 was performed to evaluate the association of proliferation and tumor angiogenesis with HOXB9 expression. RESULTS Of 141 tumor specimens immunostained for HOXB9, 69 specimens (48.9%) were positive staining. Univariate logistic regression revealed ER and PgR negativity, HER2 positivity, high nuclear grade, and large pathological tumor size as significant variables associated with HOXB9 expression. The disease-free survival (DFS) and the overall survival were significantly different between the HOXB9 positive negative group; HR=20.714, p=0.001, HR 9.206, p=0.003, respectively. A Multivariate analysis indicated that HOXB9 expression was the independent prognostic factor for DFS (HR=15.532, p=0.009). In subgroup analysis, patients with strong HOXB9 staining showed a significant increase in the number of vasculature and the Ki-67 ratio in comparison with HOXB9-negative patients. CONCLUSIONS Our results suggest that HOXB9 expression promoting the cellular proliferation and the angiogenesis in tumor microenvironment is a significant prognostic factor for clinical outcomes in breast cancer patient.

Abstract 5183: HOXB9 expression as a new metastatic biomarker for human breast cancer

Background: There are several reports showing a HOX gene family, which plays the critical roles for the differentiation during the embryonic stage, is associated with the tumorigenicity. It was demonstrated that HOXB9 is overexpressed in 42% of breast cancers, specifically those with high histological grade, and it defined the functional consequences of elevated HOXB9 expression in breast cancer. Moreover, HOXB9 expression promotes increased neovascularization and tumor metastasis to the lung in mouse xenograft models (Hayashida et al., PNAS, 2010). The purpose of this research is to evaluate the correlation between HOXB9 expression and poor prognosis in breast cancer patients. Patients and methods: A consecutive series of 141 patients with invasive ductal carcinoma who underwent surgical treatment at Keio University Hospital from January 2004 to January 2005 was involved. HOXB9 expression was analyzed immunohistochemically on formalin-fixed, paraffin-embedded tumor sections using rabbit anti-human HOXB9 polyclonal antibody. Results: The age at the diagnosis ranged from 30 to 93 years (median age, 58 years), and median observation period was 62.2 months. Of 141 tumor specimens immunostained for HOXB9, 69 specimens (48.9%) were positive staining. Univariate logistic regression revealed ER negativity (p Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 5183. doi:10.1158/1538-7445.AM2011-5183

Abstract P4-07-07: HOXB9 Expression as a New Independent Prognostic Factor in Human Breast Cancer

Background: There are several reports showing a HOX gene family, which plays the critical roles for the differentiation during the embryonic stage, is associated with the tumorigenicity. It was demonstrated that HOXB9 is overexpressed in 42% of breast cancers, specifically those with high histological grade, and we defined the functional consequences of elevated HOXB9 expression in breast cancer. Moreover, HOXB9 expression promotes increased neovascularization and tumor metastasis to the lung in mouse xenograft models (Hayashida et al., PNAS, 2010). The puropose of this report is to evaluate the correlation between HOXB9 and clinicopathological variables in breast cancer patients. Patients and methods: A consecutive series of 141 patients with invasive ductal carcinoma who underwent surgical treatment at Keio University Hospital from January 2004 to January 2005 was involved. HOXB9 expression was analyzed immunohistochemically on formalin-fixed, paraffin-embedded tumor sections using rabbit anti-human HOXB9polyclonal antibody. Moreover, immunohistochemical stainings for Ki-67, CD31, and CD34 were also performed to evaluate the association with HOXB9 expression. Results: The age at the diagnosis ranged from 30 to 93 years (median age, 58 years), and median observation period was 62.2 months. Of 141 tumor specimens immunostained for HOXB9, 69 specimens (48.9%) were positive staining. Univariate logistic regression revealed ER negativity (P in vitro and in vivo, we also evaluated the expression of vascular endothelial marker, CD31 and CD34 and cellular proliferation marker, Ki-67 in 45 patients with clinical T2 (tumor size, 2 to 5cm) tumor. In this subgroup analysis, HOXB9 positive patients (n=22) showed increased number of vasculature and Ki-67 ratio in comparison with HOXB9 negative patients (n=23) with statistical significance. Correlations between HOXB 9 expression and Ki-67, CD31 and CD 34 Conclusion: The data identify HOXB9 expression as a new independent prognostic factor in breast cancer, which might help to improve the selection for appropriate therapy. Possibly, it might be useful to determine the application of anti-angiogenic therapy. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-07-07.

Abstract P5-10-13: Phase I Dose Escalation Study of Pirarubicin in Combination with Cyclophosphamide in Breast Cancer

Background: Doxorubicin containing combination chemotherapy regimens are widely used for treatment of breast and other cancers. However, these regimens are associated with significant toxicities including myocardialdysfunction and alopecia. Analogues of doxorubicin are being developed to reduce these side effects. Pirarubicin is a more lipophilic derivative of doxorubicin, with a higher uptake rate of cells, lower cardiotoxicity and better antitumor efficacy in preclinical models. Purpose: We conducted a single-institution phase I clinical trial to determine the maximum-tolerated dose (MTD) and define the toxic effects and recommended dose (RD) of pirarubicin in combination with cyclophosphamide in patients with breast cancer. Patients and Methods: Patients who had received prior anthracycline therapy were excluded. Cohorts of three patients with breast cancer were treated with escalating doses of pirarubicin (40 to 70 mg/m 2 ) intravenously administered every three weeks in combination with cyclophosphamide (60 mg/m 2 ) for 4 or more cycles. Results: Eleven patients of stage I/II operable breast cancer received a total of 46 cycles of pirarubicin and cyclophosphamide as post-operative adjuvant chemotherapy. The most frequently reported treatment-related grade 2 adverse events were constipation (36%) and nausea (27%). There were no grade 3/4 events. Grade 2 leukocytopenia and grade 2 fatigue were dose-limiting at 70 mg/m 2 , the maximum-tolerated dose was 60 mg/m 2 . Grade 2 alopecia was reported in 60 and 70 mg/m 2 pirarubicin group. Conclusion: At the MTD of 60 mg/m 2 every 3 weeks, pirarubicin in combination with cyclophosphamide was associated with mild, reversible toxicity. The recommended phase II dose is pirarubicin 50 mg/m 2 and cyclophosphamide 60 mg/m 2 on day 1 every 21 days. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-10-13.