Repeat Breast-conserving Surgery Research Articles

Do we need reshape rTNM staging system for ipsilateral breast tumor recurrence of breast cancer? A population-based, propensity score matched cohort study.

The aim of the study was to explore the role of recurrent TNM (rTNM) staging in predicting prognosis for ipsilateral breast tumor recurrence (IBTR) and determine the optimal treatment strategy for IBTR. IBTR cases were identified from the Surveillance, Epidemiology, and End Results (SEER) database spanning the years 2000-2018. Cox proportional hazards analysis was performed to examine factors associated with overall survival (OS) and breast cancer-specific survival (BCSS). Propensity score matching (PSM) was employed to match IBTR with primary early breast cancer (EBC) based on clinicopathological characteristics. Investigations into the impact of different therapies were also included. Of the 4375 IBTR cases included in the study, the 5-year OS was 87.1%, 71.6% and 58.7% in rTNM stages I, II and III, respectively. After PSM, while IBTR patients had worse survival to primary EBC patients, prognosis of IBTR for different rTNM stage always closely aligned with the corresponding stage of primary EBC. Repeat breast-conserving surgery (BCS) with radiation therapy was equivalent to mastectomy with respect to OS and BCSS. Chemotherapy was favorable for OS and BCSS in estrogen receptor (ER)-negative IBTR or IBTR occurring within a 60-month interval. rTNM staging system has an outstanding prognostic value for survival outcome of patients with IBTR, and IBTR and primary EBC may have potentially analogous features in the context of TNM staging. BCS plus radiation therapy may be an alternative. IBTR cases who have experienced recurrence with short intervals and with ER-negative tumors might benefit from chemotherapy.

Is breast conservation surgery feasible in ipsilateral cancer recurrence with previous radiotherapy?

Introduction: Breast-conserving surgery (BCS) is the preferred modalityfor early breast cancer, yet there is a significant research gap in understandingthe feasibility of BCS in ipsilateral recurrent breast cancer(IRBC) post-radiotherapy. This systematic review aims to investigate theoutcomes of repeat BCS (rBCS) in managing IRBC, providing crucialinsights for clinicians and patients in evaluating treatment options.Methods: The PRISMA framework guided data collection from PubMedand Embase. A qualitative systematic approach involved descriptive andthematic analysis, examining patterns and consistencies in outcome findingsacross identified studies. Due to the nature of the research, no statisticalanalysis was conducted.Results: Four papers, employing a 95% confidence level, were included.Studies revealed a 2.103 risk ratio for second local recurrence (SLR) afterrBCS compared to mastectomy. Pooled data indicated SLR rates of15.7% for BCS and 10.3% for mastectomy, with a 5-year overall survival(OS) rate of 86.8 and 79.8%, respectively. Repeat radiotherapy showed aprotective effect for SLR and a small OS benefit favoured rBCS. However,this came with overall evidence certainty. Other studies found a 5-year OSof 77 and 87% after rBCS, with oncological advantages for adjunctiveradiotherapy. Post-IBTR, 84% had a 5-year survival rate, while multivariateanalysis highlighted factors influencing SLR.Conclusion: This systematic review suggests that rBCS may be consideredin a subset of patients with IBCR after BCS and RT. Individual assessmentencompassing tumour-size and duration prior to relapse showsimportance approach feasibility. However, further research wouldimprove subject knowledge and aid in optimal patient selection.

Abstract GS02-08: Five-year outcomes of the IDEA trial of endocrine therapy without radiotherapy after breast-conserving surgery for postmenopausal patients age 50-69 with genomically-selected favorable Stage I breast cancer

Abstract Background: Multiple studies have shown a low risk of ipsilateral breast events (IBE) or other recurrences for selected patients age 65-70 or older with Stage I breast cancers treated with breast conserving surgery (BCS) and endocrine therapy (ET) without adjuvant radiotherapy (RT). We designed a prospective single-arm trial, IDEA (Individualized Decisions for Endocrine therapy Alone), to see if younger postmenopausal patients could also be successfully treated without RT, adding a genomic assay to classic selection factors. Methods: Postmenopausal patients aged 50-69 with pT1N0 unifocal invasive breast cancer with margins 2 mm or wider after BCS whose tumors were ER+, PR+, and Her2- with Oncotype DX 21-gene recurrence score (RS) 18 or lower were eligible to avoid RT if they consented to take at least 5 years of ET and surveillance on study. The primary endpoint was the rate of breast cancer recurrence at 5 years of follow-up after BCS. A valid 5–year assessment was defined as a clinical assessment within 4 months prior to the 5-year anniversary or later. Follow-up time was calculated from the date of BCS until first recurrence [ipsilateral breast events (IBE) or regional or distant failures] or to last clinical follow-up. The time-to-event endpoint was calculated using the product-limit method of Kaplan and Meier measured from the date of BCS. Results: 200 eligible patients were enrolled from 13 US institutions between June 2015 and October 2018. Median age was 63 years (IQR 58-66); mean RS was 11.2 (SD 4.8). Tumors were grade 1 in 85 patients, grade 2 in 109, and grade 3 in 6. Mean tumor size was 10 mm (SD 4.6). Lymphovascular invasion was present in 16 tumors and an extensive intraductal component in 11. Median follow-up time was 5.21 years (IQR 5.01-5.97); 8 of 14 patients with less than 56 months of follow-up were lost to follow-up. Overall and breast cancer-specific survival rates at 5 years were both 100%; 2 deaths occurred later than 5 years. The 5-year freedom from recurrence was 99% (95% CI, 96%-100%). One of the two events occurring by 5 years was an isolated axillary recurrence at 21 months treated with axillary dissection and breast and regional nodal irradiation. The other was an IBE at 49 months, treated with repeat BCS. Both these patients had been compliant with ET. Six additional patients recurred later than 5 years after BCS (5 IBEs, 1 IBE plus regional recurrence). Crude rates of IBE for the entire follow-up period for patients aged 50-59 and 60-69 were 3.3% (2/60) and 3.6% (5/140), respectively; crude rates of overall relapse were 5.0% (3/60) and 3.6% (5/140). Conclusions: This multicenter trial of ET without RT following BCS achieved a very low risk of relapse for postmenopausal patients with Stage I cancers using a genomic assay in combination with classic clinical and biologic features for treatment selection, including for patients younger than age 60. IDEA demonstrates a 5-year probability of recurrence consistent with or lower than the 4% risk estimated a priori, and the patients accrued were younger when compared to prior prospective trials (e.g., PRIME II, minimum age 65; CALGB 9343, minimum age 70; LUMINA, median age 67). The results of ongoing NRG BR007 trial, which randomly allocates women meeting these eligibility criteria to receive RT or not, and similar randomized and single-arm studies will help determine whether the option of avoiding initial RT can be offered to a broader group of women than current guidelines recommend. Long-term follow-up beyond the 5-year required period of ET will be important to determine if the risk of recurrence increases, particularly after discontinuation of ET. Citation Format: Reshma Jagsi, Kent Griffith, Eleanor Harris, Jean Wright, Abram Recht, Alphonse Taghian, Lucille Lee, Meena Moran, William Small, Candice Johnstone, Asal Rahimi, Gary Freedman, Mahvish Muzaffar, Bruce Haffty, Kathleen Horst, Simon Powell, Jody Sharp, Michael Sabel, Anne Schott, Mahmoud El-Tamer. Five-year outcomes of the IDEA trial of endocrine therapy without radiotherapy after breast-conserving surgery for postmenopausal patients age 50-69 with genomically-selected favorable Stage I breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr GS02-08.

ASO Author Reflections: Do Patients with Ipsilateral Breast Tumor Recurrence Prefer Repeat Breast-Conserving Surgery or Mastectomy?

ASO Author Reflections: Do Patients with Ipsilateral Breast Tumor Recurrence Prefer Repeat Breast-Conserving Surgery or Mastectomy?

Patient Preference for Surgical Methods for Ipsilateral Breast Tumor Recurrence.

Mastectomy has been the standard surgical treatment for ipsilateral breast tumor recurrence (IBTR). Recently, there has been growing interest in repeat breast-conserving surgery (rBCS) for IBTR among breast surgeons; however, there is currently little information regarding patient preferences for surgical procedure for IBTR. The purpose of this study was to evaluate preference for surgical procedure (mastectomy vs. rBCS) among breast cancer patients who had undergone salvage surgery for IBTR. Overall, 100 breast cancer patients who had undergone salvage surgery for IBTR were asked about their preferred surgical methods for IBTR and the reason. The association of patient preference and the reasons related to various clinical and pathological factors were assessed. Of the 100 respondents, only 11 patients (11%) preferred rBCS. Patients who had undergone rBCS and radiotherapy for IBTR were significantly more likely to prefer to undergo rBCS than other groups (p = 0.030). The most frequent reason for choosing rBCS was the patient's desire to minimize breast deformity and surgical wounds. Our study revealed that there is a low rate of patients who opt to undergo rBCS among patients who had undergone salvage surgery for IBTR. Discrepancies in perceptions regarding the surgical procedure for IBTR between patients and their surgeons may exist.

Rates of reoperation after breast conserving cancer surgery in Western Australia before and after publication of the SSO-ASTRO margins guideline.

A 2014 SSO-ASTRO guideline on surgical margins aimed to reduce unnecessary reoperation after breast conserving surgery (BCS). We investigate whether publication of the guideline was associated with a reduction in reoperation in Western Australia (WA). In this retrospective, population-based cohort study, cases of newly-diagnosed breast cancer were identified from the WA Cancer Registry. Linkage to the Hospital Morbidity Data Collection identified index BCS for invasive cancer between January 2009 and June 2018 (N=8059) and reoperation within 90 days. Pre-guideline (2009-2013) and post-guideline (2014-2018) reoperation proportions were compared, and temporal trends were estimated with generalised linear regression. The pre-guideline reoperation proportion was 25.8% compared with 21.7% post-guideline (difference -4.0% [95% CI -5.9, -2.2, p<0.001], odds ratio [OR] 0.80 [95% CI 0.72, 0.89, p<0.001]). Absolute reductions were similar for repeat BCS (16.3% versus 14.6%; difference -1.8% [95% CI -3.4, -0.2, p=0.03]) and conversion to mastectomy (9.4% versus 7.2%; difference -2.2% [95% CI -3.4, -1.0, p<0.001]). Over the study period, there was an annual absolute change in reoperation of -0.8% (95% CI -1.2, -0.5, p<0.001). Accounting for this linear trend, the difference in reoperation between time periods was -0.5% (95% CI -4.3, 3.3; p=0.81), reflecting a non-significant reduction in conversion to mastectomy. Comparisons of pre- versus post-guideline time periods in WA showed reductions in reoperation that were similar to international estimates; however, an annual decline in reoperation predated the guideline. Analyses that do not account for temporal trends are likely to overestimate changes in reoperation associated with the guideline.

Early effectiveness and toxicity outcomes of reirradiation after breast conserving surgery for recurrent or new primary breast cancer

Breast reirradiation (reRT) after breast conserving surgery (BCS) has emerged as a viable alternative to mastectomy for women presenting with recurrent or new primary breast cancer. There are limited data on safety of different fractionation regimens. This study reports safety and efficacy among women treated with repeat BCS and reRT. Patients who underwent repeat BCS followed by RT from 2015 to 2021 at 2 institutions were analyzed. Univariate logistic regression models were used to identify predictors of acute and late toxicities. Kaplan-Meier estimates were used to evaluate overall survival (OS), distant metastasis-free survival (DMFS) and locoregional recurrence-free survival (LR-RFS). Sixty-six patients were reviewed with median follow-up of 16months (range: 3-60months). At time of first recurrence, 41% had invasive carcinoma with a ductal carcinoma in situ (DCIS) component, 41% had invasive carcinoma alone and 18% had DCIS alone. All were clinically node negative. For the reirradiation course, 95% received partial breast irradiation (PBI) (57.5% with 1.5Gy BID; 27% with 1.8Gy daily; 10.5% with hypofractionation), and 5% received whole breast irradiation (1.8-2Gy/fx), all of whom had received PBI for initial course. One patient experienced grade 3 fibrosis, and one patient experienced grade 3 telangiectasia. None had grade 4 or higher late adverse events. We found no association between the fractionation of the second course of RT or the cumulative dose (measured as EQD2) with acute or late toxicity. At 2years, OS was 100%, DMFS was 91.6%, and LR-RFS was 100%. In this series of patients with recurrent or new primary breast cancer, a second breast conservation surgery followed by reirradiation was effective with no local recurrences and an acceptable toxicity profile across a range of available fractionation regimens at a median follow up of 16months. Longer follow up is required.

Effectiveness and Toxicity of Re-Irradiation after Breast Conserving Surgery for Recurrent Breast Cancer: A Multi-Institutional Study

<h3>Purpose/Objective(s)</h3> Breast re-irradiation (reRT) after repeat breast conserving surgery (BCS) has emerged as a viable alternative to mastectomy in women presenting with low risk in-breast tumor recurrence (IBTR). However, there is limited data on optimal patient selection and safety of different fractionation regimens. This multi-institutional study reports safety and efficacy in a large cohort of women with IBTR treated with repeat BCS and reRT. <h3>Materials/Methods</h3> Using electronic medical record search tools, we identified all patients who underwent repeat BCS followed by breast reRT from 2015-2021 at 2 institutions. Univariate logistic regression models were used to identify clinical and dosimetric factors associated with development of acute and late toxicities. All statistical tests were two-sided, and the null hypothesis was rejected for p<0.05. Kaplan Meier methodology was used to calculate overall survival (OS), disease-free survival (DFS) and locoregional recurrence-free survival (LR-RFS). <h3>Results</h3> We identified 66 patients with an IBTR treated with repeat BCS. In the initial RT course, 55% received whole breast RT (WBI) with conventional fractionation (≤2 Gy/fraction[fx]), 29% WBI with hypofractionation (2.6-2.7 Gy/fx), 6% partial breast irradiation (PBI) ultrahypofractionation (6-8 Gy/fx) and 11% had unavailable treatment details. There was a median of 11 years between initial breast cancer and IBTR. At time of recurrence, 36% of patients had tumors located in the same quadrant as the initial cancer, 41% had invasive carcinoma with ductal carcinoma in situ (DCIS), 41% had invasive carcinoma alone, 18% had DCIS alone, 92% had tumors < 2 cm, 68% had low-intermediate grade tumors and all were clinically node negative. For reRT, 95% received PBI (57.5% 45 Gy/1.5 Gy twice daily; 27% 45 Gy/1.8 Gy daily; 10.5% hypofractionation), and 5% received WBI (45-46.8 Gy in 1.8 Gy/fx), all of whom had received PBI for the initial course. Nine patients (13%) underwent adjuvant chemotherapy and 44 (67%) adjuvant hormone therapy. Median follow-up was 16 months (range 3-60). Twenty-one patients (32%) experienced any acute ≥ grade 2 events, and 17 (26%) experienced any late ≥ grade 2 toxicities. One patient experienced grade 3 fibrosis and one patient experienced grade 3 telangiectasia at 36 months. None had grade 4 or higher late adverse events. We found no association between fractionation of reRT or cumulative dose (measured as EQD2) with acute or late toxicity. At 2 years, OS was 100%, DMFS was 91.6%, and LR-RFS was 100%. <h3>Conclusion</h3> In this large multi-institutional series of patients with recurrent breast cancer, second breast conservation surgery followed by reRT was effective with no local recurrences and excellent disease control outcomes, and toxicity appears to be acceptable. Longer follow-up and more prospective study are needed to further inform patient selection and establish the efficacy and tolerability of repeat breast conservation therapy in the setting of limited, low-risk recurrence.

Is repeat breast conservation possible for small ipsilateral breast cancer recurrence?

Most cases of ipsilateral breast tumor recurrence (IBTR) after breast-conserving surgery (BCS) involve small tumors. Although a few guidelines recommend mastectomy, several patients prefer repeat BCS (re-BCS). This study aimed to compare re-BCS and mastectomy in terms of prognosis in patients with IBTR and to identify candidates for re-BCS. The data of patients with small IBTR between 1999 and 2015 were obtained from the Surveillance, Epidemiology, and End Results database. The outcomes of interest were overall survival (OS) and breast cancer-specific survival (BCSS). Multivariable Cox proportional hazards regression models and propensity score matching were applied. Of the 3648 patients with IBTR, 2831 (77.6%) underwent mastectomy and 817 (22.4%) underwent re-BCS. The multivariate Cox model showed that re-BCS was associated with a worse OS (hazard ratio [HR], 1.342; 95% confidence interval [CI], 1.084-1.663) and BCSS (HR, 1.454; 95% CI, 1.004-2.105) compared with mastectomy. The omission of radiation after re-BCS was associated with worse survival overall and especially in patients with estrogen receptor (ER)-negative IBTR (HR, 1.384; 95% CI, 1.110-1.724; and HR, 1.577; 95% CI, 1.075-2.314, respectively). No statistically significant differences were observed in the OS and BCSS between re-BCS with radiation and mastectomy. Subgroup analysis indicated that the surgical approach was not an independent factor for survival in the ER-positive patients with IBTR. Re-BCS should be considered with caution in patients with small IBTR. However, a positive ER status can be an important factor for choosing re-BCS, and radiation therapy may improve oncological safety after re-BCS. Repeat breast-conserving surgery (re-BCS) was investigated to determine if it is safe for patients with small ipsilateral breast tumor recurrence (IBTR) after breast-conserving surgery (BCS). This population-based cohort study included 2831 patients with small IBTR. Re-BCS was associated with a worse overall survival and breast cancer-specific survival compared with mastectomy. Further analysis found that the IBTR estrogen receptor status was an important basis for choosing re-BCS, and radiation may improve oncological safety after re-BCS.

ASO Visual Abstract: A Systematic Review and Meta-analysis on the Role of Repeat Breast-Conserving Surgery for the Management of Ipsilateral Breast Cancer Recurrence.

ASO Visual Abstract: A Systematic Review and Meta-analysis on the Role of Repeat Breast-Conserving Surgery for the Management of Ipsilateral Breast Cancer Recurrence.

A Systematic Review and Meta-Analysis on the Role of Repeat Breast-Conserving Surgery for the Management of Ipsilateral Breast Cancer Recurrence.

The standard surgical management of ipsilateral breast cancer recurrence (IBCR) in patients previously treated with breast-conserving surgery (BCS) and radiotherapy (RT) is mastectomy. Recent international guidelines provide conflicting recommendations. The aim of this study was to perform a systematic literature review and meta-analysis of the oncological outcomes in patients with IBCR treated with repeat BCS (rBCS). The MEDLINE and EMBASE databases were searched for relevant English-language publications, with no date restrictions. All relevant studies providing sufficient data to assess oncological outcomes (second local recurrence [LR] and overall survival [OS]) of rBCS for the management of IBCR after previous BCS and RT were included (PROSPERO registration CRD42021286123). Forty-two observational studies met the criteria and were included in the analysis. The pooled second LR rate after rBCS was 15.7% (95% confidence interval [CI] 12.1-19.7), and 10.3% (95% CI 6.9-14.3) after salvage mastectomy. On meta-analysis of comparative studies (n=17), the risk ratio (RR) for second LR following rBCS compared with mastectomy was 2.103 (95% CI 1.535-2.883; p<0.001, I2=55.1%). Repeat RT had a protective effect (coefficient: - 0.317, 95% CI - 0.596 to - 0.038; p=0.026, I2=40.4%) for second LR. Pooled 5-year OS was 86.8% (95% CI 83.4-90.0) and 79.8% (95% CI 74.7-84.5) for rBCS and salvage mastectomy, respectively. Meta-analysis of comparative studies (n=20) showed a small OS benefit in favor of rBCS (RR 1.040, 95% CI 1.003-1.079; p=0.032, I2=70.8%). Overall evidence certainty was very low. This meta-analysis suggests rBCS could be considered as an option for the management of IBCR in patients previously treated with BCS and RT. Shared decision making, appropriate patient selection, and individualized approach are important for optimal outcomes.

Surgical Options for Ipsilateral Breast Tumor Recurrence: Mastectomy Versus Repeat Breast-Conserving Surgery

Purpose: The standard care for patients with ipsilateral breast tumor recurrence (IBTR) after breast-conserving surgery (BCS) is a total mastectomy (TM); however, there is growing interest in repeating BCS for IBTR.Methods: We retrospectively analyzed patients with IBTR who underwent initial BCS for breast cancer at our institution between January 2000 and December 2018. The Kaplan-Meier method was used to compare survival rates between the standard BCS-TM treatment group and the repeat-BCS group.Results: We enrolled 209 IBTR patients with a median follow-up of 102.3 months. No significant differences were observed in overall survival (10 years: 87.3% vs. 78.8%; hazard ratio [HR], 1.11; 95% confidence interval [CI], 0.44-2.81; p=0.821), distant metastasis free survival (10 years: 73.9% vs. 77.7%; HR, 0.80; 95% CI, 0.37-1.72; p=0.727) and disease-free survival (10 years: 57.1% vs. 65.2%; HR, 0.63; 95% CI, 0.35-1.12; p=0.115) between two groups. Repeat-BCS group showed significantly poorer locoregional recurrence free survival rate than did the TM group (HR, 2.44; 95% CI, 1.06-5.56; p=0.029) but the significance was not shown after excluding ipsilateral breast tumor recurrence events.Conclusion: No significant differences were observed in survival outcomes and recurrence rates between patients with IBTR who underwent mastectomy or repeat BCS regardless of molecular subtype, except secondary IBTR rates.

Partial Breast Reirradiation for Patients With Ipsilateral Breast Tumor Recurrence After Initial Treatment With Breast Conservation for Early Stage Breast Cancer

PurposeAccelerated partial breast irradiation (APBI), including intraoperative radiation therapy (IORT), is an evidence-based treatment option in patients undergoing breast conserving surgery (BCS) for early-stage breast cancer. However, literature regarding reirradiation for patients with ipsilateral breast tumor recurrences (IBTR) is limited. This prospective study assessed the feasibility and efficacy of using APBI in patients who had prior whole breast irradiation. Methods and MaterialsThis was a single institution, prospective study of patients who were previously treated with BCS and adjuvant whole breast radiation. At the time of enrollment, all had unifocal IBTR, histologically confirmed invasive ductal carcinoma with negative margins after repeat BCS. Patients received either IORT in a single fraction at time of BCS or MammoSite brachytherapy twice daily over 5 days. Follow-up data and patient surveys were collected at 1, 3, 6, 9, and 12 months, then annually for at least a 5-year period. ResultsFrom 2008 to 2014, 13 patients were enrolled. Median time to recurrence after initial course of radiation was 12.5 years. Median follow-up after retreatment was 7.8 years. One patient in the IORT group had a subsequent tumor bed recurrence, yielding a local control of 92%. One patient had distant recurrence. At baseline, 680 reported excellent-good cosmesis compared with 42% at 5 years. All patients indicated total satisfaction with overall treatment experience. ConclusionsAPBI using IORT was well tolerated with excellent local control and may be a reasonable alternative to mastectomy for IBTR. Further study is needed to determine the most suitable candidates for this approach.

The MARECA (national study of management of breast cancer locoregional recurrence and oncological outcomes) study: National practice questionnaire of United Kingdom multi-disciplinary decision making

IntroductionEvidence based guidelines for the optimal management of breast cancer locoregional recurrence (LRR) are limited, with potential for variation in clinical practice. This national practice questionnaire (NPQ) was designed to establish the current practice of UK breast multidisciplinary teams (MDTs) regarding LRR management. MethodsUK breast units were invited to take part in the MARECA study MDT NPQ. Scenario-based questions were used to elicit preference in pre-operative staging investigations, surgical management, and adjuvant therapy. Results822 MDT members across 42 breast units (out of 144; 29%) participated in the NPQ (February–August 2021). Most units (95%) routinely performed staging CT scan, but bone scan was selectively performed (31%).For patients previously treated with breast conserving surgery (BCS) and radiotherapy, few units (7%) always/usually offered repeat BCS. However, in the absence of radiotherapy, most units (90%) always/usually offered repeat BCS. For patients presenting with isolated local recurrence following previous BCS and SLNB (sentinel lymph node biopsy), most units (95%) advocated repeat SLNB. Where SLNs could not be identified, 86% proceeded to a four-node axillary sampling procedure.For ER positive, HER2 negative, node negative local recurrence, 10% of units always/usually offered chemotherapy. For ER positive, HER2 negative, node positive local recurrence, this recommendation increased to 64%. For triple negative breast cancer local recurrence, 90% of units always/usually offered chemotherapy. ConclusionThis survey has highlighted where consistencies and variations exist in the multidisciplinary management of breast cancer LRR. However, further research is required to determine how these management patterns influence patient outcomes, which will further refine optimal treatment pathways.

Radiological Underestimation of Tumor Size Influences the Success Rate of Re-Excision after Breast-conserving Surgery.

Failure to achieve adequate margins after breast-conserving surgery often leads to re-excision, either by repeat breast-conserving surgery (BCS) or by mastectomy. Despite the high frequency of this problem, the success rate of achieving adequate margins by repeat BCS is not well documented. The objective of this study was to determine the success rate of repeat BCS and identify the factors influencing that rate. A retrospective review was performed of all women undergoing repeat BCS for inadequate margins after initial BCS in our breast unit between 2013 and 2019. Univariate and multivariate analyses were carried out to identify the factors influencing how often adequate margins were achieved after repeat BCS. One hundred fifty-four patients underwent repeat BCS after initially inadequate margins, of which adequate margins were achieved in 82%. Patients with successful repeat BCS had smaller tumors, had less underestimation of tumor size on imaging, and were less likely to have had cavity shaves taken at their initial BCS. A tumor size more than 50% larger than predicted by imaging was independently associated with failure of repeat BCS in multivariate analysis (odds ratio: 3.6, 95% CI: 1.41-9.20, p = 0.007). Underestimation of tumor size by imaging was commoner and more extensive in patients with larger tumors and those with ductal carcinoma in situ. Re-excision by cavity shaves has a high success rate and should be offered to all patients who are deemed suitable for the procedure. Patients whose tumors are more than 50% larger than predicted by imaging should be counseled about the higher risk of failure.

PR77 - BREAST CONSERVING SURGERY VERSUS SALVAGE MASTECTOMY FOR IPSILATERAL BREAST CANCER RECURRENCE: A PROPENSITY SCORE MATCHING ANALYSIS

Salvage mastectomy is regarded as the treatment of first choice for ipsilateral breast cancer recurrence (IBCR), even if a second breast conserving surgery (BCS) is feasible. The purpose of this study was to compare the long-term oncological outcomes of IBCR patients who had undergone either mastectomy or second BCS, performing a propensity score matching (PSM) analysis to reduce the selection bias. All the consecutive patients with IBCR were retrospectively reviewed and divided into two different groups of treatment: repeat BCS versus salvage mastectomy. The propensity score predicting the probability of surgical treatment was determined for each patient and a 1:1 matching was performed. Disease-free survival (DFS), distant disease-free survival (DDFS), overall survival (OS), and breast cancer-specific survival (BCSS) were analyzed and compared between the two groups. A total of 309 patients underwent surgical treatment for IBCR. After PSM, 108 patients treated with repeat BCS and 108 patients treated with salvage mastectomy were included in the analysis. There was no significant difference in terms of DFS between patients with IBCR receiving repeat BCS or salvage mastectomy (p = 0.167). However, patients with IBCR undergoing second BCS had significantly better DDFS, OS, and BCSS compared to salvage mastectomy (p < 0.001). Salvage mastectomy should not be considered the optimal treatment for IBCR and it does not seem to improve prognosis compared to repeat conserving surgery. Second BCS for IBCR is a safe option with encouraging long-term oncological outcomes and should be proposed to all patients, when technically feasible.

Breast conserving surgery versus salvage mastectomy for ipsilateral breast cancer recurrence: a propensity score matching analysis.

Salvage mastectomy is regarded as the treatment of first choice for ipsilateral breast cancer recurrence (IBCR), even if a second breast conserving surgery (BCS) is feasible. The purpose of this study was to compare the long-term oncological outcomes of IBCR patients who had undergone either mastectomy or second BCS, performing a propensity score matching (PSM) analysis to reduce the selection bias. All the consecutive patients with IBCR were retrospectively reviewed and divided into two different groups of treatment: repeat BCS versus salvage mastectomy. The propensity score predicting the probability of surgical treatment was determined for each patient and a 1:1 matching was performed. Disease-free survival (DFS), distant disease-free survival (DDFS), overall survival (OS), and breast cancer-specific survival (BCSS) were analyzed and compared between the two groups. A total of 309 patients underwent surgical treatment for IBCR. After PSM, 108 patients treated with repeat BCS and 108 patients treated with salvage mastectomy were included in the analysis. There was no significant difference in terms of DFS between patients with IBCR receiving repeat BCS or salvage mastectomy (p = 0.167). However, patients with IBCR undergoing second BCS had significantly better DDFS, OS, and BCSS compared to salvage mastectomy (p < 0.001). Salvage mastectomy should not be considered the optimal treatment for IBCR and it does not seem to improve prognosis compared to repeat conserving surgery. Second BCS for IBCR is a safe option with encouraging long-term oncological outcomes and should be proposed to all patients, when technically feasible.

Abstract PS1-16: Ipsilateral breast cancer recurrence: Treatment and long-term oncological results at a high volume center

Abstract Background A small proportion of patients with primary breast cancer who receive breast conserving surgery (BCS) will develop an ipsilateral breast cancer recurrence (IBCR). In these patients, mastectomy is still considered the treatment of first choice, even if a second conservative surgical approach is technically feasible. The aims of our study are to analyze the characteristics of patients with IBCR after BCS, evaluate and compare the different treatment modalities (repeat BCS vs. mastectomy) in terms of patients and tumor characteristics, disease-free interval (DFI), disease-free survival (DFS), and overall survival (OS).MethodsOur prospectively maintained institutional database was queried, and 309 patients with IBCR after BCS who underwent either repeat BCS or mastectomy, between January 2008 and December 2018, were identified. Ipsilateral breast cancer recurrence was defined as a local tumor reappearance in the same breast or in the surgical scar. Exclusion criteria were: age &amp;lt;18 years, primary cancer treated with mastectomy, residual disease, controlateral recurrence, recurrent benign disease, only distant or axillary recurrence, IBCR not treated surgically, follow-up &amp;lt;24 months, and DFI &amp;lt;6 months.ResultsThe mean age of patients at primary breast cancer was 55.3 years. The majority of primary tumors were ductal (87.4%), luminal A-B (81.2%) breast cancers. After BCS, 222 (71.8%) patients underwent radiotherapy. Out of 309 patients with IBCR after BCS, 143 underwent repeat BCS and 166 underwent mastectomy. At multivariable analysis, young age, &amp;lt;65 years (59.6% vs. 37.1% if age ≥65 years, odds ratio (OR)=2.374, 95% confidence interval (95%CI)=0.02-0.24, p= 0.018) and short DFI &amp;lt;24 months (15.7% vs. 10.5% if DFI ≥24 months, OR=2.705, 95%CI=0.02-0.17, p= 0.007) were found to significantly increase the probability to receive mastectomy for IBCR after BCS. After IBCR, DFS rate at 3-, 5-, and 10-years was 79.2%, 68.2%, 36.9%, and 77.2%, 65.9%, 55.3%, in patients receiving repeat BCS or mastectomy, respectively (p = 0.842). Overall-survival rate at 3-, 5-, and 10-years was 95.4%, 91.4%, 68.5%, and 87.3%, 69.3%, 57.9%, in patients receiving repeat BCS or mastectomy, respectively (p = 0.018).ConclusionsThe best candidates for repeat BCS in the treatment of IBCR are patients ≥65 years with a DFI ≥24 months. Young patients (&amp;lt;65 years) with early onset of recurrence (DFI &amp;lt;24 months) have a high probability to receive mastectomy for the treatment of IBCR. Mastectomy does not improve survival in patients with IBCS after BCS. The information about the risk of poor long-term prognosis after mastectomy should be shared with the patient and a repeat BCS could be proposed. Citation Format: Damiano Gentile, Andrea Sagona, Chiara Annunziata Pasqualina Anghelone, Erika Barbieri, Emilia Marrazzo, Wolfgang Gatzemeier, Giuseppe Canavese, Valentina Errico, Alberto Testori, Corrado Tinterri. Ipsilateral breast cancer recurrence: Treatment and long-term oncological results at a high volume center [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS1-16.

Ipsilateral Breast Cancer Recurrence: Characteristics, Treatment, and Long-Term Oncologic Results at a High-Volume Center

IntroductionSalvage mastectomy is considered the treatment of choice for ipsilateral breast cancer recurrence (IBCR), even if a second breast-conserving surgery (BCS) is feasible. The purpose of this study was to describe the characteristics of IBCR patients, to compare the 2 therapeutic options in terms of long-term outcomes, and to identify independent factors that may predict the type of treatment. Patients and MethodsA total of 309 IBCR patients who underwent either repeat BCS or mastectomy were identified. All the analyzed patients with IBCR had true recurrence. ResultsRepeat BCS and salvage mastectomy were performed in 143 and 166 patients, respectively. Age < 65 years (59.6% vs 37.1% if age ≥ 65 years; odds ratio, 2.374; 95% confidence interval, 0.92-5.24; P = .018) and disease-free interval < 24 months (15.7% vs 10.5% if disease-free interval ≥ 24 months; odds ratio, 2.705; 95% confidence interval, 1.42-5.97; P = .007) were found to significantly increase the probability of receipt of mastectomy. Disease-free survival rates at 3, 5, and 10 years were 79.2%, 68.2%, and 36.9%; and 77.2%, 65.9%, and 55.3% in patients receiving repeat BCS or mastectomy, respectively (P = .842). Overall survival rates at 3, 5, and 10 years were 95.4%, 91.4%, and 68.5%; and 87.3%, 69.3%, and 57.9%, respectively, in patients receiving repeat BCS or mastectomy (P = .018). ConclusionSalvage mastectomy should not be considered the only treatment option for IBCR. A second BCS can still be evaluated and proposed to IBCR patients, with acceptable locoregional control and survival. The risk of poor long-term prognosis after mastectomy should be shared with the patient.

PCN149 TREATMENT PATTERNS FOR WOMEN UNDERGOING BREAST CONSERVING SURGERY AFTER A NEWLY DIAGNOSED BREAST CANCER

This retrospective review describes surgical treatment patterns, surgical healthcare costs and complication rates in women who received breast conserving surgery (BCS). The IBM MarketScan Commercial and Medicare database was used to identify a retrospective cohort of women aged 21 years and older who underwent BCS within 180 days of a new diagnosis of breast cancer between 2013 and 2018. Only women who had ≥12 months of continuous insurance enrollment pre and post cancer diagnosis were eligible for inclusion. Outcomes were the frequency, timing, and costs of additional surgeries (repeat BCS, mastectomy, breast reconstruction) and complications following BCS. 5,584 women treated with BCS were included. The median time between diagnosis and initial BCS was 23 days. Approximately one quarter (27%) of women receiving BCS underwent additional surgery (mastectomy or repeat BCS) within 1 year of diagnosis. The median time between initial and subsequent surgeries was 48 days for women undergoing repeat BCS and 42 days for women undergoing mastectomy following BCS. Women with repeat BCS incurred an average of $6,823 in total healthcare costs on the day of their repeat BCS and women receiving mastectomy incurred an average of $26,783 in healthcare costs on the day of mastectomy. 10% of women undergoing initial BCS had breast reconstruction within 1 year. The median time between initial BCS and reconstruction was 29 days. Women undergoing breast reconstruction incurred an average of $28,181 in healthcare costs on the day of breast reconstruction. Among women undergoing BCS, 25% were diagnosed with pain, 7% with lymphedema, 4% with seroma, 3% with breast abscess within 1 year of undergoing BCS. Approximately one-third (37%) of women who underwent breast conserving surgery following a breast cancer diagnosis have additional surgery at significant additional direct cost ($6,823 to $28,181). Complications were noted in more than a third of women post-BCS.