Aiko Nagayama

Comparative Effectiveness of Neoadjuvant Therapy for HER2–Positive Breast Cancer: A Network Meta-Analysis

BACKGROUND The growing number of antihuman epidermal growth factor receptor-2 (HER2) agents suggests the need for defining the optimal choice of neoadjuvant therapy for HER2-positive breast cancer. This study aims to assess the efficacy and safety of neoadjuvant therapy for HER2-positive breast cancer. METHODS Randomized trials that compared different anti-HER2 regimens in the neoadjuvant setting were included. The odds ratio (OR) for pathological complete response (pCR), treatment completion, and safety was utilized for pooling effect sizes. Network meta-analysis using a Bayesian statistical model was performed to combine the direct and indirect evidence of neoadjuvant therapy for HER2-positive breast cancer. All statistical tests were two-sided. RESULTS A database search identified 1047 articles, with 10 studies meeting the eligibility criteria. A total of 2247 patients in seven different treatment arms were assessed. Anti-HER2 agents evaluated included trastuzumab (tzmb), lapatinib (lpnb), and pertuzumab (pzmb). Network meta-analysis showed no statistically significant difference between dual targeting treatment arms; however, lpnb reduced treatment completion due to adverse events. Patients in dual targeting arms had statistically significantly more pCR than those in other treatment arms (chemotherapy [CT] + tzmb + pzmb vs CT + tzmb, OR = 2.29, 95% credibility interval = 1.02 to 5.02, P = .02). The surface under the cumulative ranking probability curve indicated that CT + tzmb + pzmb had the highest probability of being the best treatment arm in terms of pCR. CONCLUSIONS This study indicates that combining two anti-HER2 agents with CT is the most effective treatment modality in the neoadjuvant setting for HER2-positive breast cancer.

Clinical predictors of pathological complete response to neoadjuvant chemotherapy in triple-negative breast cancer

The response of triple-negative breast cancer (TNBC) to chemotherapy is heterogeneous; particular subtype classifications based on mRNA gene expression analysis have been demonstrated to be associated with a pathological complete response (pCR). The aim of the present study was to investigate additional clinical and pathological characteristics associated with pCR status. The pathological and clinical characteristics of 40 TNBC patients who underwent neoadjuvant chemotherapy followed by surgery were retrospectively analyzed by dividing the cases into two groups according to the response to treatment: pCR (n=12) and non-pCR (n=28). Clinically, patients in the pCR group presented tumors with a significantly less advanced Tumor-Node-Metastasis stage (P=0.030) and mammographic calcification was less common (17 vs. 58%; P=0.034). Pathologically, whereas all cases in the pCR group (12/12, 100%) were of the histological type ‘invasive ductal carcinoma, not otherwise specified’ (IDC-NOS), the non-pCR group consisted of a lower proportion of IDC-NOS cases (20/28, 71%) and more cases of special histological types, including mucinous, metaplastic, medullary and apocrine carcinomas (P=0.079). The positive rates of androgen receptor (AR) and forkhead-box A1 (FOXA1) tended to be lower in the pCR group (AR, 0 vs. 29%, P=0.079; FOXA1, 8 vs. 29%, P=0.233). The Ki-67 score was significantly higher in the pCR group than in the non-pCR group (P=0.041). The results suggest that patients with TNBC who present with clinically less advanced tumors and less frequent mammographic calcification are more likely to respond to chemotherapy. From a pathological standpoint, IDC-NOS type, negative AR status and higher Ki-67 scores may be associated with chemotherapy sensitivity.

Antibody–Drug Conjugates for the Treatment of Solid Tumors: Clinical Experience and Latest Developments

Antibody–drug conjugates (ADCs) are complex immunoconjugates designed to selectively deliver toxic small molecules preferentially to cancer cells. These immunoconjugates consist of a monoclonal antibody - directed to a tumor antigen - and a cytotoxic agent that is conjugated to the antibody via a molecular linker. Following the binding to a specific antigen on the surface of cancer cells, the conjugate is internalized and releases its cytotoxic payload to kill the malignant cell. ADCs that have gained regulatory approval from the US Food and Drug Administration (FDA) include brentuximab vedotin for CD30-positive Hodgkin’s lymphoma and trastuzumab emtansine for human epidermal growth factor receptor 2 (HER2)-positive breast cancer. Several other agents are in advanced stages of clinical development, including sacituzumab govitecan for breast cancer, mirvetuximab soravtansine for ovarian cancer, rovalpituzumab tesirine for lung cancer, depatuxizumab mafodotin for glioblastoma, and oportuzumab monatox for bladder cancer. This review provides an overview of the recent clinical experience with the approved, most advanced, and other promising candidates of ADCs for solid tumors, including a description of biology and chemistry of ADCs, drug resistance and biomarkers, and the future perspective on combination strategies with these new immunoconjugates.

The updated network meta-analysis of neoadjuvant therapy for HER2-positive breast cancer

BACKGROUND We previously described a systematic assessment of the neoadjuvant therapies for human epidermal growth factor receptor-2 (HER2) positive breast cancer, using network meta-analysis. Accumulation of new clinical data has compelled us to update the analysis. METHODS Randomized trials comparing different anti-HER2 regimens in the neoadjuvant setting were included, and odds ratio for pathologic complete response (pCR) in seven treatment arms were assessed by pooling effect sizes. Direct and indirect comparisons using a Bayesian statistical model were performed. All statistical tests were two-sided. RESULTS A database search identified 993 articles with 13 studies meeting the eligibility criteria, including three new studies with lapatinib (lpnb). In an indirect comparison, dual anti-HER2 agents with CT achieved a better pCR rate than other arms. The credibility intervals of CT + tzmb + lpnb arm were largely reduced compared to our former report, which we added sufficient clinical evidence by this update. Values of surface under the cumulative ranking (SUCRA) suggested that CT + tzmb + pzmb had the highest probability of being the best treatment arm for pCR, widening the difference between the top two dual-HER2 blockade arms compared to our former report. The overall consistency with our first report enhanced the credibility of the results. CONCLUSION Network meta-analysis using new clinical data firmly establish that combining two anti-HER2 agents with CT is most effective against HER2-positive breast cancer in the neoadjuvant setting. New pzmb related trials are required to fully determine the best neoadjuvant dual-HER2 blockade regimen.

Abstract P3-06-49: Prognostic impact of discordance in hormone receptor status after the neoadjuvant chemotherapy in primary breast cancer

Background : Hormone receptor (Estrogen receptor (ER), Progesterone receptor (PgR)) is an important biological marker for predicting prognosis and making effective treatment decisions. Discordance in these biomarkers between the primary tumor and recurrent lesions is reported frequently. However, it is not well known whether these biomarkers are affected by neoadjuvant chemotherapy and their impacts on outcomes still remain to be elucidated. The aim of the present study is to evaluate the changes in HR status after neoadjuvant chemotherapy in patients with operable breast cancer and their relationship with response to treatment and prognosis. Patients and Methods : Of 162 patients with stage II/III breast cancer patients receiving neoadjuvant chemotherapy from January 2005 to September 2012 at Keio University Hospital, 140 patients with non-pCR were analyzed. Patients were treated with sequential anthracycline and taxane. ER and PgR were assessed in both CNB performed prior to neoadjuvant chemotherapy and surgical samples. HR status was assessed by immunohistochemistry (IHC). ER/PgR status was determined using the Allred score and defined as positive when score was 3 and more. HR status was considered positive in cases of ER and/or PgR positivity. Pathological response criteria were classified as grade 0, 1, 2, or 3: grade 0 includes almost no change in cancer cells; grade 1 includes slight or marked changes in less than two thirds of area; grade 2 includes marked changes in more than two thirds of area; grade3 includes necrosis or disappearance of all tumor cells. Results : ER, PgR and HR positive rates before neoadjuvant chemotherapy were 72.9%, 67.1% and 76.4%, respectively. Changes in ER, PgR and HR status between CNB and surgical samples were 12.1% (4.3% gain; 7.8% loss), 17.1% (2.1% gain; 15.0% loss) and 9.3% (2.9% gain; 6.4% loss), respectively. In ER-discordant group, grade 2 rate of pathological response was significantly higher than ER- concordant group (61.1% vs. 30%, p=0.033), whereas there were no significant differences of pathological response between discordant and concordant group in PgR status. In the disease free survival (DFS), there were no significant difference between concordance and discordance group for ER, PgR and HR (p=0.216, 0.859, 0.233) after a median follow-up of 40.4 months. But patients with a loss in ER and/or HR status had a trend to a shorter DFS compared with the concordant ER and/or HR-positive group (p=0.169 and 0.154) Conclusions : After neoadjuvant chemotherapy, discordance of biomarkers was seen in 5-20%. The pathological response was significantly associated with the change in ER status. A loss in ER and/or HR status may affect a prognosis of breast cancer after neoadjuvant chemotherapy, but still need further investigation. Citation Format: Toshiaki Kurihara, Hanako Ueno, Masaru Takemae, Aiko Nagayama, Maiko Takahashi, Tetsu Hayashida, Hiromitsu Jinno, Yuko Kitagawa. Prognostic impact of discordance in hormone receptor status after the neoadjuvant chemotherapy in primary breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P3-06-49.

Abstract P3-13-11: Response to treatment and prognosis of recurrent breast cancer patients with receptor discordance

BACKGROUND Estrogen receptor (ER), progesterone receptor (PgR) and human epidermal growth factor receptor -2 (HER2) statuses are clinically used to select treatments. Several studies reported that discordance between primary and metastatic lesions lead to detrimental outcome. Although biopsy of recurrent breast cancer has been recently recommended by international clinical guidelines, prognostic relevance remains to be elucidated. The aim of the present study is to evaluate response to treatment and prognosis of patients with receptor discordance, compared with patients with receptor concordance. Patients and METHODS We retrospectively identified recurrent breast cancer patients who had biopsies or resections of recurrent lesions between January 2007 and April 2012 at Keio University Hospital. HR status was assessed by immunohistochemistry (IHC) and determined using the Allred score. HR status was defined as positive when score was 3 and more. HER2 status was assessed by IHC and fluorescence in situ hybridization (FISH) analysis. We defined HER2 positivity as 3+ staining intensity by IHC or the presence of HER2 gene amplification by FISH. Tumors were classified as luminal (HR+ and HER2-), luminal/HER2 (HR+ and HER2+), HER2 (HR- and HER2+), or triple negative (HR- and HER2-). Treatment was decided according to the receptor status of recurrent tumors. RESULTS Among 38 patients undergoing biopsy or resection, 13.2% (5) were loco-regional recurrences and 86.8% (33) were distant metastases (lung 21; liver 6; brain 3; pleura 1). Overall, 10 patients (26.3%) changed subtypes at recurrent lesions (table1) and all of them had a change in treatment plan. Changes in management included the addition of trastuzumab in patients with gain of HER2 (n=3), the use of chemotherapy in those with loss of HR (n=6) and provision of endocrine therapy for those with gaining HR (n=3). Response rate of discordant group and concordant group were 10.0% and 21.4%, respectively (p=1.000). Clinical benefit rate of discordant group and concordant group were 40.0% and 67.9%, respectively (p=0.150). There is no significant difference of time to progression (TTP) between the discordant and concordant groups (169.5days vs.319.5days, p= 0.081). CONCLUSION Patients with receptor discordance tended towards worse response rate and shorter TTP, leading to the poor prognosis of the recurrent breast cancer patients with receptor discordance. Citation Format: Hanako Ueno, Hiromitsu Jinno, Takamichi Yokoe, Toshiaki Kurihara, Masaru Takemae, Aiko Nagayama, Maiko Takahashi, Tetsu Hayashida, Kaori Kameyama, Yuko Kitagawa. Response to treatment and prognosis of recurrent breast cancer patients with receptor discordance [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P3-13-11.

Abstract P1-14-09: Immunohistochemical classification of intrinsic subtypes as a predictive biomarker of pathological compelete response in breast cancer patients treated with preoperative chemotherapy.

Background: Analysis of gene expression arrays has resulted in the recognition of several fundamentally different subtypes of breast cancer. These subtypes have different natural histories and different responses to systemic and local therapies. However, widespread use of gene expression profiling is limited because of its expense and of technical difficulty. Alternatively, this classification has also been reproduced in immunohistochemical studies. The objective of this study was to evaluate the clinical utility of immunohistochemical classification of breast cancer intrinsic subtypes in the prediction of pathological compelete response (pCR) in a cohort of breast cancer patients receiving the sequential combination of taxane followed by anthracycline as preoperative chemotherapy. Materials and methods: A prospective database of 150 women with stage II/ III breast cancer, who received neoadjuvant chemotherapy, was analyzed. The regimens were either four cycles of docetaxel (40 mg/m 2 on day 1 every 3 weeks) with S-1 (80 mg/m 2 on days 1–14 every 3 weeks) followed by four cycles of 5-fluorouracil (500 mg/m 2 ), epirubicin (100 mg/m 2 ) and cyclophosphamide (500 mg/m 2 ) (FEC) or four cycles of docetaxel (60 mg/m 2 on day 8 every 3 weeks) with capecitabine (1650 mg/m 2 on days 1–14 every 3 weeks) followed by four cycles of FEC. Subtypes were classified into luminal A (lumA) (ER+ and/or PgR+, HER2−, Ki67 14%), triple-positive (TP) (ER+ and/or PgR+, HER2+), HER2 (ER−, PgR−, HER2+), and triple-negative (TN) (ER−, PgR−, HER2−) by using immunohistochemically stained specimen obtained by core needle biopsy. Absence of invasive tumor cells in the breast at the time of surgery was defined as pCR. Results: We found 34 women in lumA, 54 in lumB, 15 in TP, 8 in HER2, 33 in TN. The median age in each group was 53, 51, 50, 57 and 53 respectively (p = .397). The mean tumor size was 3.2cm, 3.5cm, 4.4cm, 3.9cm and 3.6cm respectively (p = .158). The clinical response rate measured by physical examination (calliper) was 80.6%, 93.9%, 86.7%, 100% and 82.4% (p = .378). pCR rate was 5.9%, 14.8%. 13.3%, 50%, 21.2% respectively (p = .031). The multivariate analysis showed ER negative, PgR negative and intrinsic subtype (TN) were the significant predictive factors of pCR (p = .027, p = .003, p = .004). Conclusion: This study indicated that immunohistochemical classification of intrinsic subtype might be a useful predictive biomarker of pCR in breast cancer patients treated with preoperative chemotherapy. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-14-09.