Locoregional recurrence-associated factors and risk-adapted postmastectomy radiotherapy for breast cancer staged in cT1-2N0-1 after neoadjuvant chemotherapy

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Open Access Full Text Article Locoregional recurrence-associated factors and risk-adapted postmastectomy radiotherapy for breast cancer staged in cT1-2N0-1 after neoadjuvant chemotherapy This article was published in the following Dove Press journal: Cancer Management and Research Xin Wang Liming Xu Zhenzhen Yin Daquan Wang Qi Wang Kunpeng Xu Jinlin Zhao, Lujun Zhao Zhiyong Yuan Ping Wang Department of Radiation Oncology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin’s Clinical Research Center for Cancer, Key Laboratory of Breast Cancer, Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, 300060, China Objective: In order to identify risk factors associated with locoregional recurrence (LRR) and assess the role of postmastectomy radiotherapy (PMRT) in early breast cancer (BC), managed with neoadjuvant chemotherapy (NAC) and mastectomy, a retrospective analysis of BC diagnosed with clinical stage T1-2N0-1 was conducted. Patients and methods: A total of 217 patients were included in this analysis. The median age was 50 years (24–72 years). The clinical stage distributions were cT1 in 15 cases, cT2 in 202, cN0 in 53, and cN1 in 161 cases. All patients were treated with NAC and mastectomy, and 128 patients received PMRT. Results: With a median follow-up time of 61 months, the 5-year cumulative LRR rate was 12%. Multivariate analysis demonstrated that pathological N stage, lymph-vascular invasion, and histological grade were independent prognostic factors associated with LRR. A nomogram model based on these factors was established, based on which the patients were deeply stratified into low- and high-risk group. In the low-risk group, radiotherapy did not decrease LRR (3.3% in PMRT group, 1.7% in no PMRT group, P=0.192). While in the high-risk group, PMRT significantly decreased LRR (21.8% in PMRT group, 42.2% in no PMRT group, P=0.031). Conclusion: Lymph-vascular invasion, histological grade, as well as pathological N stage were important prognostic factors associated with LRR in BC patients staged in cT1-2N0-1, who were managed with NAC and mastectomy. In our cohort, not only clinical and pathological stage information but also other risk factors were taken into consideration when adjuvant PMRT was recommended. In the high-risk subgroup, PMRT significantly improved the prognosis. Keywords: breast cancer, neoadjuvant chemotherapy, postmastectomy radiotherapy, prognosis Introduction Correspondence: Ping Wang Department of Radiation Oncology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin’s Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Huanhuxi Road, Tianjin 300060, China Tel +86 186 2222 1112 Fax +86 22 2334 5607 Email In recent decades, neoadjuvant chemotherapy (NAC) has become common for treatment of breast cancer (BC). With the downstage of NAC, some inoperable diseases may regain chances of surgery, and those who would have originally required mastectomy maybe able to undergo breast-conserving surgery (BCS).1–5 Therefore, NAC has been used for locally advanced diseases and also early-staged BC.6,7 However, there were also some concerns of NAC such as cancer may progress, potential of over- or under-treatment, and limited evidence base to guide adjuvant treatment. Furthermore, upfront surgery followed by adjuvant chemotherapy assured an accurate assessment of disease at the time of initial treatment. Due to the inconsistency of clinical evaluation of the disease extent both at diagnosis and post-NAC, the evaluation of locoregional submit your manuscript | www.dovepress.com Cancer Management and Research 2018:10 4105–4112 Dovepress © 2018 Wang et al. This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms. php and incorporate the Creative Commons Attribution – Non Commercial (unported, v3.0) License (http://creativecommons.org/licenses/by-nc/3.0/). By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms (https://www.dovepress.com/terms.php). http://dx.doi.org/10.2147/CMAR.S173628 4105 Dovepress Wang et al recurrence (LRR) risks becomes more complex. Though it is well established that patients with stage III/IV, or positive node ≥4, harboring high LRR rates and postmastectomy radiotherapy (PMRT) show significantly reduced LRR and improved survival,8–12 there is little information available on stage I–II disease after NAC and mastectomy. For cT1-2N0-1 disease, even in the adjuvant settings, the value of PMRT has remained an issue of controversy until now. The addition of NAC in this subgroup will significantly mask the indication for PMRT and complicate the situation. LRR risks at the time of presentation and post-NAC, as well as biologic response to NAC, should be taken into consideration. This may lead to the recommendation of PMRT in early BC after NAC is determined on a case-by-case basis. In order to evaluate the LRR rate and identify associated risk factors, a retrospective analysis of cT1-2N0-1 BC postNAC and mastectomy was conducted, helping to provide some evidence for the recommendation of adjuvant PMRT. Patients and methods Patient characteristics Patients with BC staged in cT1-2N0-1M0 and treated with mastectomy after NAC in our institute between 2011 and 2013 were retrospectively analyzed. All patients underwent mammography and breast ultrasonography prior to chemotherapy. Clinical nodal status was determined by physical examination and ultrasound. Patients with distant metastasis, inflammatory or bilateral breast cancer, and previous or concurrent malignancy were excluded. A total of 217 patients met the inclusion criteria. The clinical stage was determined according to American Joint Committee on Cancer criteria (seventh edition). The clinical stage distributions were cT1 in 15, cT2 in 202, cN0 in 53, and cN1 in 164 patients. This study was approved by Tianjin Medical University Cancer Institute and Hospital’s Ethics Committee. And a waiver for individual patients’ consent for this retrospective study was also obtained from this committee. To maintain confidentiality, relevant medical records, laboratory results, images, and histo (...truncated)