No abstract

#1151 Purpose
 To compare the efficacy of adriamycin and cyclophosphamide (AC) followed by tamoxifen (AC->T) with gonadotropin-releasing hormone analog plus tamoxifen (GnRHa+T) in premenopausal women with hormone-response, node-negative breast cancer.
 Patients and Methods 
 We retrospectively reviewed the records of 587 premenopausal women with hormone- responsive, node-negative breast cancer. Of these, 269 were treated with AC->T, and 318 were treated with GnRHa (goserelin acetate 3.6 mg/kg or leuprorelin acetate 3.75 mg/kg every 28 days subcutaneously)+T. The main study outcome was disease-free survival (DFS).
 Results
 At a median follow-up time of 30 months, eight patients had relapsed and three had died. DFS did not differ between the AC->T and GnRHa+T groups. Of the three deaths, two were not related to breast cancer. The third patient, in the AC ->T group, died because of brain metastasis. GnRHa+T treatment had no effect on blood profile and did not cause the development of detrimental symptoms but decreased bone mineral density. The efficacy of leuprorelin was similar to that of goserelin.
 Conclusion 
 GnRHa +T and AC->T had comparable efficacy after 30 months of follow-up. The efficacy and tolerability of leuprorelin acetate was similar to that of goserelin. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1151.

Background: Previous studies have shown that progesterone receptor (PR) status has a prognostic value in hormone receptor-positive breast cancer. In this study, we evaluated the clinical significance of PR status in estrogen receptor (ER)-positive and HER2-positive breast cancer. Methods: We retrospectively analyzed the data of ER+ and HER2+ breast cancer patients who underwent surgery at Gangnam Severance hospital and Severance hospital from 2002 to 2012. We excluded patients who had a history of previous cancer, received neoadjuvant chemotherapy, did not received adjuvant chemotherapy, and had contralateral breast cancer or metastasis at diagnosis. A total of 346 patients were identified. Among them, 155 patients (44.8%) received adjuvant trastuzumab. Results: At a median follow-up of 59 months, median disease-free survival (DFS) and overall survival (OS) were 56 and 59 months, respectively. The DFS and OS showed no difference according to PR status in overall patients. Then, these patients were categorized into two groups: ER+/HER2+/PR+ and ER+/HER2+/PR-. In ER+/HER2+PR+ patient, there was no difference of DFS or OS according to trastuzumab use. In ER+/HER2+/PR- patients, DFS was significantly better in patients who received adjuvant trastuzumab treatment compared to those who did not (p=0.009). We also analyzed influence of PR status on treatment outcome between patients who received adjuvant trastuzumab and those who did not. In patients who received adjuvant trastuzumab, there was no difference of DFS or OS according to PR status. However, in patients who did not receive adjuvant trastuzumab, ER+/HER2+/PR- patients showed worse DFS than ER+/HER2+/PR+ patients (p=0.006). Conclusions: In patients with ER+/HER2+ breast cancer, we found that a prognostic value of PR only retained in those who did not receive adjuvant trastuzumab. Our findings suggest that the use of adjuvant trastuzumab may offer less clinical benefit for the patients with ER+/HER2+/PR+ breast cancer. Citation Format: Lee HW, Ahn SG, Park JT, Yang BS, Park S, Jeong J, Kim SI. The association between the expression of progesterone receptor and clinical benefit of adjuvant trastuzumab in estrogen receptor-positive and HER2-positive 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 P3-07-10.

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.

Background: Newly released guideline standardizing a negative margin after breast-conservative surgery (BCS) as “no ink on tumor” by SSO-ASTRO stressed the importance of estimation tumor extent with comprehensive breast imaging studies. To evaluate clinical value of breast magnetic resonance imaging (MRI) in patients with BCS, we compared the degree of correlation between MRI-pathology and ultrasonography (US)-pathology according to subtypes. In addition, we investigated the margin-positive rates and secondary operation rates for margin clearance. Methods: We identified patients with invasive breast cancer who had preoperative breast MRI and ultrasound between 2011 and 2016. We excluded patients having large tumor more than 5cm or multiple tumors or undergoing mastectomy. Patients were classified into 4 subtypes based on the immunohistochemistry; luminal A, luminal B/HER2, HER2, triple-negative breast cancer (TNBC). Lin's concordance correlation coefficient was used to measure the agreement between the MRI or US and tumor extent. Tumor extent was defined as pathologic tumor size including in situ carcinoma. Margin-positivity was assessed based on intraoperative frozen examination. Results: A total 516 patients with single tumor undergoing BCS were included. Means of tumor size were 1.99 ± 0.91 cm by pathologic examination, 1.91 ± 1.01 cm by MRI, and 1.76 ± 0.92 cm by US, respectively. The correlation coefficient of MRI-pathology was significantly higher than that of US-pathology (r=0.6975 vs. 0.6211, P=0.001). A superiority of MRI than US in measuring pathologic extent was only observed in TNBC (r=0.8089 vs. 0.6014, P<0.001), whereas the agreement between the MRI or US and tumor extents was low in the HER2 (MRI: 0.3509, US: 0.3165). Also, the margin-positive rate was higher in HER2 (luminal A, 11.6%; luminal B/HER2, 17.5%; HER2, 29.6%; TNBC, 17.8%; P=0.0382). In the post-hoc test, the HER2 was more likely to have positive margin compared to Luminal A (P=0.0039). There is no significant difference in secondary operation as margin clearance according to the subtypes (P>0.999). Margin positive and re-excision rates according to the subtypes Luminal A (n=302)Luminal B (n=80)HER2 (n=27)TNBC (n=107)P valuePositive margin35 (11.6)14 (17.5)8 (29.6)19 (17.8)0.0382Re-excision14 (4.6)4 (5.0)1 (3.7)5 (4.7)>0.9999 Conclusions: Given a superiority of MRI to US in preoperative assessment, MRI-guided BCS did not reduce the margin-positive rate in TNBC. In the HER2, size correlation of MRI-pathology was very low, and the margin-positive rate was high. Collectively, our findings suggest that accuracy of MRI has limited value to reduce the margin-positive rate. Citation Format: Bae SJ, Ahn SG, Yoon C, Cha YJ, Jeong J. Accuracy of breast magnetic resonance imaging has limited value to reduce the margin-positive rate: A study in relation to the molecular subtypes [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 P4-02-11.