Increasing Mastectomy Rates Research Articles

Abstract IA024: DCIS and MRI: Challenges translating MRI depiction of DCIS to improved clinical performance and future opportunities to optimize treatment

Abstract The value of breast MRI for DCIS detection and characterization remains highly debated. Though initially thought to be poor for DCIS detection, MRI is now well-established as the most superior imaging tool for DCIS detection and characterization. This is particularly true of high nuclear grade subtypes, possibly due MRI’s ability to not only reflect neovascularity but also basement membrane permeability. NMEs account for the majority of DCIS lesions identified on MRI and generally reflect a pathology growth pattern that extends along the milk ducts. Rarer presentations of DCIS as masses or foci may indicate a more indolent DCIS growth pattern that primarily expands rather than spreads along the milk ducts. DCIS exhibits variable semi-quantitative kinetic features, generally peaking later than invasive cancers and often resulting in medium initial phase and/or delayed phase persistent or plateau. The appearance of DCIS on diffusion weighted imaging and novel ultrafast sequences remains areas of active investigation. MRI is also more accurate than mammography at determining DCIS extent. Of nine studies published to date, eight concluded that MRI span is more accurate than mammographic span. However, the practical surgical benefit of this improved depiction of DCIS is less clear, with a meta-analysis and a recent systematic review showing no reduction in re-operation rate with preoperative MRI. Two more recent prospective multicenter trials (E4112 and IRCIS) and two newer retrospective studies have suggested that MRI may be associated with better surgical outcomes without increasing mastectomy rates. Still, there remains uncertainty in how MRI affects surgical management of DCIS. It is possible that MRI’s improved depiction of DCIS will only be of substantial clinical benefit when guiding future treatment de-escalation approaches to mitigate overtreatment, such as guiding multiple lumpectomies in lieu of mastectomies and/or omitting radiation therapy. Advances in artificial intelligence applied to radiological image features to develop and validate imaging biomarkers have created a major opportunity for MRI to assist with DCIS management by further illuminating lesion biology and heterogeneity. Prior studies have suggested that simple MRI features can correlate with basic pathologic features, such as nuclear grade, comedonecrosis, or ER positivity. MRI-based radiomic features have recently been shown to predict clinical outcomes such as ipsilateral breast recurrent for invasive cancers. Two pilots studies of DCIS and MRI radiomics demonstrated that quantitative parameters could predict nuclear grade and HER2 amplification and IBR. Preliminary data from the E4112 trial also has suggested that MRI radiomic features results in two distinct phenotypes that may have independent prognostic value. Future trials of DCIS should carefully standardize imaging approaches so that imaging markers can be developed and validated to improve DCIS management. Citation Format: Habib Rahbar. DCIS and MRI: Challenges translating MRI depiction of DCIS to improved clinical performance and future opportunities to optimize treatment [abstract]. In: Proceedings of the AACR Special Conference on Rethinking DCIS: An Opportunity for Prevention?; 2022 Sep 8-11; Philadelphia, PA. Philadelphia (PA): AACR; Can Prev Res 2022;15(12 Suppl_1): Abstract nr IA024.

Tumor size assessment of invasive breast cancers: which pathological features affect MRI-pathology agreement?

BackgroundPreoperative assessment of tumor size is important in breast cancer treatment planning, especially in breast conservation surgeries. The use of the Magnetic Resonance Imaging (MRI) is increasing among patients with newly diagnosed breast cancers. However, some pathological features can overestimate the measurement of tumor size by MRI, increasing mastectomy rates. The objective is to evaluate which pathological features may affect the agreement between MRI and pathologic tumor size on invasive breast carcinomas.MethodsEighty seven patients with breast cancer who underwent preoperative breast MRI were retrospectively evaluated. The main tumor size measured by MRI was compared with pathology (gold standard) and concordance was defined as a greater diameter difference of less than 10 mm.ResultsThere was MRI-pathology concordance in 60 cases (69.0%), MRI overestimated tumor size in 21 (24.1%) and underestimated in 6 (6.9%). After multivariate analysis, only associated ductal carcinoma in situ (DCIS) remained significantly related to overestimation of tumor size on MRI (OR: 9.00; 95% IC:1.13-71.87; p = 0.038).ConclusionThere was good correlation between tumor size evaluation on MRI and pathology. The presence of associated DCIS was the only pathological parameter associated with size overestimation on MRI.

Trends in breast reconstruction practices in a specialized breast tertiary referral centre.

BackgroundBreast reconstruction is an important component of multidisciplinary breast cancer management. The practice of breast reconstruction after mastectomy has evolved significantly in the past decade as a result of both increasing mastectomy rates and advances in reconstructive strategy. These changes have significantly influenced the contemporary surgical management of breast cancer. The aim of this study was to examine trends in breast reconstruction after mastectomy in an Irish population.MethodsData were reviewed from a database of all patients who had mastectomy with or without breast reconstruction at Galway University Hospital, a tertiary breast cancer referral centre, between 2004 and 2014. Trends in breast reconstruction after mastectomy were explored with respect to patient demographics, clinicopathological features, and neoadjuvant and adjuvant therapy.ResultsOf 1303 patients who underwent mastectomy during interval studied, 706 (54.2 per cent) had breast reconstruction after mastectomy. In 629 patients (89·1 per cent), breast reconstruction was performed in the immediate setting. Reconstruction rates increased over time from 20·5 per cent in 2004 to 44·7 per cent in 2014. Reconstruction was more commonly performed in younger patients and those with benign, in situ and early‐stage disease. A negative relationship between radiotherapy and reconstruction was observed. A pedicled flap with or without an implant was the most commonly used reconstructive approach in patients receiving radiotherapy.ConclusionBreast reconstruction after mastectomy has become the standard of care in the surgical treatment of breast cancer. Recent trends show a transition favouring implant‐based approaches.

Is there an Ideal Breast Conservation Rate for the Treatment of Breast Cancer?

Since the results of randomised controlled trials in the last quarter of the twentieth century were reported, it has been conventionally accepted that breast conservation treatment (BCT) provides equivalent survival to mastectomy for early breast cancer. As expected, there was an initial fall in the use of mastectomy. The first decade of the twenty-first century, however, witnessed a trend of increasing mastectomy rates in some regions. This perplexing circumstance served as an impetus for a relook at survival outcomes with each surgical modality. Recent studies have demonstrated higher survival rates and improved local control associated with BCT. Such findings warrant a re-evaluation of treatment strategies, beginning with whether there is an optimum BCT rate.

Role of Breast MRI in Patients with Newly Diagnosed Breast Cancer

The role of breast MRI in patients with newly diagnosed breast cancer is controversial. Preoperative MRI is highly sensitive and accurate in assessing tumor size, extensive intraductal component (EIC), and in detection of additional sites of disease. It also has utility in assessing chest wall, nipple-areolar complex, and nodal involvement. Yet there are conflicting results in whether the use of preoperative MRI improves re-excision rate, local recurrence rate, and ultimately, survival. MRI has also been associated with overestimation of disease and increased mastectomy rates, and may contribute to treatment delay. Nevertheless, certain subgroups of patients may benefit more from preoperative MRI than others, including those with invasive lobular cancer (ILC), dense breasts, and those at elevated risk for breast cancer.

Rethinking Preoperative Breast Magnetic Resonance Imaging.

Although magnetic resonance imaging (MRI) is exquisitely sensitive for detecting breast cancer, its precise clinical benefit in the routine preoperative setting is uncertain, and determinationof itsappropriateuse todatehasbeenchallenging.1 Early randomized prospective trials were hindered by low numbers, wide variation in imaging quality, and inconsistencies in incorporating MRI findings into treatment planning. Larger, more recent, retrospective trialshave reportedcorrelationsbetweenuseofbreast MRI and increased mastectomy rates but have been significantly limited by not controlling for key variables that are independentlyassociatedwithmastectomyrates.2-4Womenwho undergo preoperative MRI comprise a distinct subset of patients: theyaremore likely tobeyoung, athigh risk,havedense breast tissue, have genetic mutations, have more aggressive tumor subtypes, be seen at academic subspecialized centers thatoffer advanced reconstructive surgical techniques, andbe in ahigher socioeconomic status group than thosewhodonot undergo MRI. These factors themselves are known to be associatedwith higher rates ofmastectomies2,5; thus, failure to control for these variables is a significant limitation of retrospective studies seekingmeaningful correlationsbetweenMRI use and outcomes. Most important, correlation does not imply causation. In this issueof JAMAOncology, Arnaout et al6 evaluate the utilization of preoperative breast MRI. Using a populationbased cancer registry in Ontario, Canada, to identify incident breast cancers in thepreoperative setting, the authors6 found that preoperative MRI was performed in less than 15% of all patients diagnosed ashavingbreast cancer. The authors6 confirmedwhatothershavereported:womenwhounderwentpreoperative breast MRI were more likely to be young, at higher socioeconomic status, anddiagnosedashaving invasive lobular cancers at higher stage comparedwithwomenwhodidnot receive MRI. Patients seen at teaching hospitals or by surgeonswithhighervolumeswhomorerecentlycompletedtraining were more likely to undergo breast MRI. They6 also found differences in short-term surgical outcomesbetweenpatientswhounderwentbreastMRIand those who did not, including longer wait-times between diagnosis and surgery, higher rates of additional imaging and/or biopsies prior to surgery, and higher rates of ipsilateral and contralateralprophylacticmastectomy.Recognizingthat theseoutcomes aredependent onpatient, surgeon, and systemfactors, the authors6 controlled for some variables, such as socioeconomic status, age, tumor histologic type, patient comorbidity, surgeon experience, and the environment (academic vs community-basedpractice) inwhichapatientwas treated.Unfortunately, theauthorswerenotable tocontrol forgeneticmutation status, family history, or breast density. The authors6 suggest that rising breastMRIuse inwomen newly diagnosed as having breast cancer may contribute to a general problem of breast cancer overtreatment by prompting unnecessary additional imaging tests, biopsies, andmastectomies either in the affected breast or the unaffected contralateral breast. Because abnormalities identified on breast MRI require samplingprior todefinitive treatment, it isnot surprising that preoperative breastMRI prompts additional tests and biopsies, which in turn can lead to longer wait times between diagnosis and surgery. Furthermore, because MRI detectsmammographicallyoccultmulticentricdisease in roughly 10% of patients, and mastectomy is currently indicated for women with multicentric disease, it is logical that mastectomy rates would rise with its use. Finally, it is reasonable to believe that additional procedures resulting from falsepositive examinations could result in higher patient anxiety, tipping the scales toward more mastectomies. However, it is important to interpret the outcomes associatedwithobtainingpreoperative breastMRI from this study with some caution. Because the authors6 did not report MRI results (eg, if the MRI was interpreted as positive or negaRelated article page 1238 Opinion Editorial

A misperceived threat: Understanding the increasing mastectomy rates.

75 Background: Rates of unilateral (UM) and contralateral prophylactic mastectomy (CPM) for early-stage breast cancer (ESBC) have been increasing. Both surgeons’ preference and patients’ choice have been suggested to play a role. Methods: A qualitative study was conducted examining surgeon’s practices and patient’s decision-making during treatment for ESBC. The Health-Belief Model was applied identifying factors influential in the choice for UM+/-CPM. Purposive sampling identified non-high-risk women across Toronto, Canada who were candidates for breast conserving therapy (BCT) but underwent UM+/-CPM. Academic and community breast surgeons from across Ontario, Canada and the United States were also recruited. Data were collected through semi-structured interviews. Constant comparative analysis identified key ideas. Results: 29 patients and 45 surgeons were interviewed. The dominant theme was the ‘misperceived threat of ESBC: an overestimated risk’. Surgeons described the high survivability of ESBC, yet patients greatly overestimated the threat of death from their cancer and strived to eliminate this threat by choosing UM+/-CPM. Surgeons described BCT and UM as equivalent treatment options for ESBC, and recommended BCT. In this average-risk population CPM was discouraged by the surgeons describing no survival advantage; despite this, women requested UM+CPM. Personal cancer experiences with family and friends were extremely influential in women’s request for UM+/-CPM. Previous negative experiences translated into an overestimated risk of recurrence, contralateral cancer, metastasisand subsequent death. Patients’ misperceived the severity of ESBC, and believed that by choosing UM+/-CPM they would live longer. Most women did not perceive any risks of undergoing mastectomy, yet many had ongoing issues with skin sensation, cosmesis and body image. Conclusions: Despite surgeons counseling otherwise, women greatly overestimated the risk of ESBC and misperceived the benefits of mastectomy. As undergoing UM+/-CPM is not without risks, improved discussion of patient sources of information and fears around survival may benefit surgical consultations, facilitating informed decision-making.

Toolbox to Reduce Lumpectomy Reoperations and Improve Cosmetic Outcome in Breast Cancer Patients: The American Society of Breast Surgeons Consensus Conference.

BackgroundMultiple recent reports have documented significant variability of reoperation rates after initial lumpectomy for breast cancer. To address this issue, a multidisciplinary consensus conference was convened during the American Society of Breast Surgeons 2015 annual meeting.MethodsThe conference mission statement was to “reduce the national reoperation rate in patients undergoing breast conserving surgery for cancer, without increasing mastectomy rates or adversely affecting cosmetic outcome, thereby improving value of care.” The goal was to develop a toolbox of recommendations to reduce the variability of reoperation rates and improve cosmetic outcomes. Conference participants included providers from multiple disciplines involved with breast cancer care, as well as a patient representative. Updated systematic reviews of the literature and invited presentations were sent to participants in advance. After topic presentations, voting occurred for choice of tools, level of evidence, and strength of recommendation.ResultsThe following tools were recommended with varied levels of evidence and strength of recommendation: compliance with the SSO-ASTRO Margin Guideline; needle biopsy for diagnosis before surgical excision of breast cancer; full-field digital diagnostic mammography with ultrasound as needed; use of oncoplastic techniques; image-guided lesion localization; specimen imaging for nonpalpable cancers; use of specialized techniques for intraoperative management, including excisional cavity shave biopsies and intraoperative pathology assessment; formal pre- and postoperative planning strategies; and patient-reported outcome measurement.ConclusionsA practical approach to performance improvement was used by the American Society of Breast Surgeons to create a toolbox of options to reduce lumpectomy reoperations and improve cosmetic outcomes.

Surgical margin reporting in breast conserving surgery: Does compliance with guidelines affect re-excision and mastectomy rates?

PurposeMargin status is important in guiding decisions to re-excise following breast-conserving surgery (BCS) for breast cancer. The College of American Pathologists (CAP) developed guidelines to standardize pathology reporting; however, compliance with margin documentation guidelines has been shown to vary. The aim of this retrospective study was to determine whether compliance with CAP guidelines affects re-excision and mastectomy rates. MethodsWe identified 1423 patients diagnosed with breast cancer between 1998 and 2006 who underwent BCS with negative margins. CAP compliance was categorized as maximal, minimal, or non-compliant. Statistical analyses were performed comparing the frequency of re-excision and mastectomy after initial BCS according to CAP margin reporting guideline compliance. Data were adjusted for provider facility by including a clustering variable within the regression model. ResultsPatients with non-compliant margin reporting were 1.7 times more likely to undergo re-excision and/or mastectomy than those with maximally compliant reporting. Level of compliance was most strongly associated with the frequency of mastectomy; non-compliant margin reporting was associated with a 2.5-fold increase in mastectomy rates compared to maximally compliant reporting. The results did not substantially change when the analyses accounted for clustering at the provider facility level. ConclusionsOur findings suggest that compliance with CAP guidelines in pathology reporting may be associated with variation in re-excision and mastectomy rates following BCS.

Abstract AL-2: William L. McGuire memorial lecture – Local therapy in the molecular era: Relevant or relic?

Abstract Surgery has always been driven by disease burden; initially, to determine operability, and recently, to select patients for BCT. Systemic therapy also initially relied on disease burden (axillary nodes, tumor size), but gene profiles and molecular targets now predominate in selecting systemic therapy. Reliance on disease burden as a determinant of the intensity of local therapy is problematic as advanced imaging modalities and molecular pathology allow detection of increasingly smaller tumors. The application of management strategies proven beneficial for macroscopic tumor to subclinical disease has the potential for overtreatment as evidenced by increased mastectomy rates in patients undergoing preoperative MRI, and use of ALND and chemotherapy for sentinel node micrometastases. It is an appropriate time to ask how recognition of molecular subtypes and improvements in systemic therapy can be leveraged to improve local therapy outcomes and decrease the burden of therapy. Recognition that systemic therapy results in a major decrease in the rate of IBTR was the major impetus for SSO and ASTRO to commission a systemic review on margins for BCT in stage I and II breast cancer as the evidence base for a consensus conference. We concluded that evidence that margins more widely clear than no ink on tumor significantly improve local control was lacking and the routine practice of obtaining more widely clear margins is not indicated. Adoption of this approach has the potential to spare many women unnecessary surgery. The morbidity of ALND can also be avoided in many patients. The ACOSOG Z0011 trial showed no benefit to ALND for patients with 1 or 2 sentinel node metastases receiving WBRT and systemic therapy. There were many criticisms of this study, but 3 other prospective randomized trials (NSABP B04, NSABP B32, IBCSG 2013) demonstrate that residual axillary nodal disease does not translate to regional recurrence or a decrease in survival in a 1:1 ratio, and that systemic therapy greatly reduces the incidence of regional recurrence. In a prospective study of the applicability of Z0011 findings to an unselected population of women meeting study eligibility criteria, we found that only 16% of 287 consecutive patients had metastases in ≥3 sentinel nodes or matted nodes identified intraoperatively, sparing 84% ALND. These examples represent initial steps in reducing the morbidity of local therapy. Moving forward, it is appropriate to ask whether patients with favorable molecular profiles (luminal A), require the same local therapy as those with other molecular subtypes. More controversially, the success of HER2 blockade in improving survival raises the question of whether effective targeted therapy could allow a reduction in local therapy intensity. A major barrier to progress is the belief of many clinicians and patients that bigger surgery is better surgery. The full realization of multidisciplinary care will occur when improvements in outcomes with one modality result in studies examining the elimination of other treatments which may no longer be beneficial to patients. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr AL-2.

Abstract P2-18-12: Surgical management of breast cancer: Breast conserving surgery or mastectomy in the 2010 SEER registries by hormone receptor and HER2 status

Abstract Background Breast conserving therapy and mastectomy have been shown to have similar overall survival outcomes in large trials. After many years of decline, mastectomy rates are on the rise for a variety of reasons. In this context, there is increasing discussion that the risk of loco-regional recurrence is complex and varies by breast cancer subtype. Several, pre-trastuzumab-era, reports have shown that loco-regional recurrence is higher for HER2+ and triple negative breast cancer (TNBC) patients who undergo breast conserving therapy (BCS) compared with women with hormone receptor positive (HR+) disease. Other literature has suggested that some breast cancer subtypes have better outcomes with BCS. To provide the most recent data on surgical choice by breast cancer subtype, we report BCS and mastectomy rates from 2010 SEER data. Surgical choice is presented for ductal carcinoma in situ (DCIS) and invasive breast cancer. For women with invasive disease the subcategories of HR+, HER2+ and TNBC are reported. Methods SEER data were used to identify incident breast cancer patients diagnosed in 2010. Only pathologically confirmed cases were included. In addition, individuals were excluded if they were diagnosed at autopsy or by death certificate, did not receive surgery or if the type of surgery was unknown. Patients were categorized as having received BCS or mastectomy and, for invasive disease, by receptor subtype (HR+, HER2+ and TNBC). For invasive cancers, patients with unknown receptor subtypes were excluded. Results SEER data for 2010 included 65,598 women, 13,849 (21.1%) women had DCIS and 51,749 (78.9%) had invasive disease (Table 1). For invasive cancers after excluding 5,062 patients with unknown receptor status, 12.1% were TNBC, 14.4% were HER2+, and 83.5% were HR+. Overall, 43.5% of women underwent mastectomy (33.2% for DCIS). Mastectomy rate increased by stage at diagnosis: 33.5% for Stage I, 53.9% for Stage II disease and 77.8% for Stage III (OR = 0.49, p<0.001 for Stage 1 compared to other stages). By age, mastectomy rates were 69.0% for <30, 53.4% for 30-49, 43.3% for 50-59, 39.0% for 60-69, 39.4% for 70-79 and 41.1% for 80+ (OR = 2.90, p<0.001 for women under 30 compared to older women). Conclusions In this large, recent series, 43.5% of women underwent mastectomy. This rate is among the highest reported from population-based registries and suggests a continued trend of increasing mastectomy rates. Women with HER2+ and TNBC were younger and significantly more likely to have mastectomy than their HR+ counterparts. Women with HER2+ breast cancer, in this trastuzumab-era cohort, were the subtype most likely to choose to undergo mastectomy. Monitoring for relapse events could contribute to a better understanding of how loco-regional recurrence risk might vary by subtype and surgical choice. Table 1: Percent receiving BCS and mastectomy by subtype for invasive cancersReceptor StatusNMean AgeBCS (%)Mastectomy (%)Odds Ratio*p valueFull cohort51,74961.354.145.9 HR+38,98161.855.744.30.68<0.001HER2+6,73858.143.056.01.61<0.001TNBC5,65858.849.150.91.26<0.001* Odds Ratio of undergoing mastectomy versus lumpectomy for this subtype compared to those not of this subtype. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-18-12.

Fluctuating Mastectomy Rates Across Time and Geography

In 2009, 2 single-institution studies from the United States reported increasing mastectomy rates during the last decade. We have recently reported unilateral mastectomy trends from a European database and demonstrated a significant trend of decreasing mastectomy rates from 38.1 % in 2005 to 13.1 % in 2010. A recent study from the SEER registry in the United States confirmed a previously reported decrease in mastectomy rates from 40.1 % in year 2000 to 35.6 % in 2005, but showed a statistically significant increase in mastectomy rates up to 38.4 % in 2008. This report provides evidence that mastectomy trends may be in opposite directions in different geographical areas. The sharpest increase in mastectomy rates across all ages in the recent SEER study occurs right after year 2005, which interestingly corresponds with the time of publication of the meta-analysis by the EBCTCG that highlighted the importance of local control in breast cancer. The coincident timing raises the question of whether this evidence may have indirectly triggered an increase in mastectomy rates in the United States that would partially explain the observed trend, and more importantly, of whether an increase would be justified on this basis. Multiple factors influence the proportion between mastectomy and breast conservation, so it may be unreasonable to think of an optimal cutoff. There is not necessarily a right or wrong direction for mastectomy trends, but aiming to determine explanations for these differences may help provide a clearer insight of the decision-making process involved in the surgical management of breast cancer.

Preoperative Magnetic Resonance Imaging in Breast Cancer

The role of breast magnetic resonance imaging (MRI) in women newly diagnosed with breast cancer (BC) is controversial. This meta-analysis examines the effect of preoperative MRI compared with standard preoperative assessment on surgical outcomes, focusing on studies that used a controlled design. Using random-effects logistic meta-regression modeling, we estimated the proportion of women with each outcome in the MRI versus no-MRI groups, and calculated the odds ratio (OR) and adjusted OR (adjusted for study-level median age, and, where appropriate, for temporal effect) for each model. There were 9 eligible studies (2 randomized trials; 7 comparative cohorts). Outcomes in 3112 patients with BC (any histological tumor type) for MRI versus no-MRI (referent) were as follows: initial mastectomy 16.4% versus 8.1% [OR, 2.22 (P < 0.001); adjusted OR, 3.06 (P < 0.001)]; re-excision after initial breast conservation 11.6% versus 11.4% [OR, 1.02 (P = 0.87); adjusted OR, 0.95 (P = 0.71)]; overall mastectomy 25.5% versus 18.2% [OR, 1.54 (P < 0.001); adjusted OR, 1.51 (P < 0.001)]. In 766 patients with invasive lobular cancer (ILC), outcomes were as follows: initial mastectomy 31.1% versus 24.9% [OR, 1.36 (P = 0.056); adjusted OR, 2.12 (P = 0.008)]; re-excision after initial breast conservation 10.9% versus 18.0% [OR, 0.56 (P = 0.031); adjusted OR, 0.56 (P = 0.09)]; overall mastectomy 43.0% versus 40.2% [OR, 1.12 (P = 0.45); adjusted OR, 1.64 (P = 0.034)]. Our summary of the evidence showed that MRI significantly increased mastectomy rates and suggests an unfavorable harm-benefit ratio for routine use of preoperative MRI in BC. We found weak evidence that MRI reduced re-excision surgery in patients with ILC -although this was at the expense of increased mastectomies-and overall patient benefit from MRI in ILC is not clear from this study.

Increasing Mastectomy Rates Among all Age Groups for Early Stage Breast Cancer: A 10-Year Study of Surgical Choice

First-line surgical options for early stage breast cancer and ductal carcinoma in situ include breast conserving surgery or mastectomy. We analyzed factors that influence the receipt of mastectomy and resultant trends over time. Registry analysis was carried out for 21,869 women who underwent up-front surgical treatment for stage 0, I or II breast cancer between 1998 and 2007 using data from the Kentucky Cancer Registry. We examined the trend of treatment over time and assessed the probability of receiving mastectomy using multivariate logistic regression. Overall, 54.5% of women received breast conservation and 45.5% received mastectomy over a 10-year period (annual BCS rate range: 46.9-61.2%). The overall mastectomy rate substantially decreased from 53.1% in 1998 to 38.8% in 2005 (p < 0.0001), but then increased to 45% in 2007 (p < 0.001). Between 2005 and 2007, the increase in mastectomies in the age groups of <50 years, 50-69 years, and ≥ 70 years was 7.5% (p = 0.0351), 4.9% (p = 0.0132) and, 8.0% (p = 0.0283), respectively. On multivariate analysis, the rate of receiving mastectomy was drastically higher for women with stage I or II (versus in situ) disease and moderate or poorly differentiated (versus well differentiated) histology. The rate was modestly higher for uninsured and government-insured (versus privately insured) patients, patients older than 70 years (versus younger), rural (versus urban) location, receptor negative (versus receptor positive) disease, and unusual histologies (versus ductal and lobular histology). There was no statistically significant difference in surgical choice with regard to race. Determinants of mastectomy for in situ and early stage breast cancer include stage, histology, age, insurance status, county of residence, receptor status. The rate of mastectomy declined until 2005 and is now increasing across all age groups, especially for women < 50 years and ≥ 70 years.

Are mastectomy rates really increasing? Experiences from a single institution and a population-based database.

1028 Background: Recent studies have reported increased mastectomy rates for the treatment of early stage breast cancer during the last decade. The aims of this study were to examine trends in mastectomy rates at a single institution and in a population-based database and to compare differences between the two cohorts. Methods: Patients with stage 0-II breast cancer diagnosed from 2000 to 2008 were identified from our cancer center institutional database (CC cohort, n=8,915) and the Surveillance, Epidemiology and End Results database (SEER cohort, n=359,572). Patients without primary surgery or unknown surgery type were excluded. Mastectomy rates by the year of diagnosis were evaluated and multivariable logistic regression models were built to identify clinicopathologic factors that predicted mastectomy as the treatment choice. Results: The proportion of patients treated with mastectomy decreased from 44.5% to 37.8% between 2000 and 2005 in the CC cohort (P=0.003) and from 42.8% to 36.6% in the SEER cohort (P&lt;0.0001). Subsequently, the mastectomy rate increased to 48.6% in the CC cohort (P&lt;0.0001) and to 40.1% in the SEER cohort by 2008 (P&lt;0.0001). Multivariable analysis found that patients with younger age (&lt;50), stage 0 or II cancer vs. stage I, high grade tumor, low median household income, and lobular histology were more likely to choose mastectomy in both the SEER and CC cohorts. In the CC cohort, patients with preoperative breast MRI were also more likely to undergo mastectomy. The percentages of patients receiving preoperative MRI and choosing prophylactic contralateral mastectomy increased each year in the CC cohort. The rate of preoperative breast MRI increased from 4.7% in 2005 to 9.6% in 2008 (P&lt;0.0001). Patients choosing prophylactic contralateral mastectomy increased from 8.4% in 2005 to 11.8% in 2008 (P=0.06). Conclusions: Our study shows that there was a decrease in mastectomy rates from 2000 to 2005 and a subsequent increase in mastectomy rates from 2005-2008 in both the CC and SEER cohorts. Increased use of preoperative breast MRI and the decision to undergo contralateral prophylactic mastectomy likely contributed to the increased mastectomy rates in the CC cohort.

Mastectomy trends for early-stage breast cancer: A report from the EUSOMA multi-institutional European database

IntroductionRecent single-institution reports have shown increased mastectomy rates during the last decade. Further studies aiming to determine if these reports could be reflecting a national trend in the United States of America (US) have shown conflicting results. We report these trends from a multi-institutional European database. Patients and methodsOur source of data was the eusomaDB, a central data warehouse of prospectively collected information of the European Society of Breast Cancer Specialists (EUSOMA). We identified patients with newly diagnosed unilateral early-stage breast cancer (stages 0, I or II) to examine rates and trends in surgical treatment. ResultsA total of 15,369 early-stage breast cancer cases underwent surgery in 13 Breast Units from 2003 to 2010. Breast conservation was successful in 11,263 cases (73.3%).Adjusted trend by year showed a statistically significant decrease in mastectomy rates from 2005 to 2010 (p=0.003) with a progressive reduction of 4.24% per year. A multivariate model showed a statistically significant association of the following factors with mastectomy: age <40 or ⩾70years, pTis, pT1mi, positive axillary nodes, lobular histology, tumour grade II and III, negative progesterone receptors and multiple lesions. ConclusionOur study demonstrates that a high proportion of patients with newly diagnosed unilateral early-stage breast cancer from the eusomaDB underwent breast-conserving surgery. It also shows a significant trend of decreasing mastectomy rates from 2005 to 2010. Moreover, our study suggests mastectomy rates in the population from the eusomaDB are lower than those reported in the US.

P2-15-01: Surgical Patterns of Care after Magnetic Resonance Imaging in the Academic Setting in Patients with Operable Breast Cancer Treated with Neoadjuvant Systemic Therapy: A Secondary Analysis of TBCRC 017.

Abstract Background: Neoadjuvant chemotherapy is increasingly used to downstage locally advanced tumors, test new regimens, and improve chances of breast conservation. In parallel, use of breast MRI for surgical planning and as a potential response biomarker has also increased along with an observed increase in mastectomy rates. This secondary analysis reports surgical patterns of care across 8 NCI comprehensive cancer centers in women receiving both neoadjuvant therapy and breast MRIs. Methods: 770 women from 8 institutions were retrospectively identified as having received neoadjuvant systemic therapy with MRI done before and after systemic treatment. Univariate and multivariate analyses of covariates associated with surgical management were performed. Within MRI complete response or not, the Jonckheere-Terpstra Test (JTT) was used to test for a trend in mastectomy rate by T stage. Results: Surgical data was available on 763/770 patients. Table 1 lists MRI response by pretreatment imaging size and final breast surgery. Distribution of pretreatment imaging-defined T stage was as follows: T1 66 (8%), T2 436 (57%), T3 230 (30%), and T4 36 (5%). 347/763 (45%) patients received breast conserving surgery and 416/763 (55%) had a mastectomy. 58% vs 43% (p=0.0003) of those with an incomplete vs complete MRI response had a mastectomy, respectively. Univariate logistic regression analysis of covariates significantly associated with use of mastectomy included ER- status (p=0.01), incomplete MRI response (p=0.0003), higher T stage (p&amp;lt;0.0001), chemotherapy regimen (p=0.006), younger age (p&amp;lt;0.0001), and institution (p=0.002); all except chemotherapy regimen and institution remained independent predictors of mastectomy on multivariate analysis. Patients with larger baseline T stage and an incomplete response on MRI (P&amp;lt;0.001) were more likely to undergo mastectomy. Overall, breast conservation was low (262/495, 53%) of all T1-T2 patients, especially in the T1 subset (26/65, 40%). Conclusions: In a contemporary group of women treated with preoperative chemotherapy at NCI designated cancer centers and with available pre/post MRI, we observed a lower frequency of breast conservation as compared to historical data from prospective randomized trials. Larger tumor size at baseline was associated with higher mastectomy rates. However, even among those with a complete MRI response, 43% had a mastectomy. In addition to clinical response and MRI findings, factors not examined here (e.g., BRCA status, education level, and patient/provider preference) may influence the decision-making process and deserve further evaluation. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-15-01.

Mammography screening and surgical breast cancer treatment in Norway.

177 Background: We have investigated whether the introduction of organized mammography screening in Norway led to less aggressive breast cancer surgery in the invited age group. Methods: We obtained aggregate incidence and surgical treatment data for women treated for ductal carcinoma in situ or invasive breast cancer from the Norwegian Cancer Registry. Rates of breast operations (mastectomy plus breast conserving therapy) and rates of mastectomy only for three age groups; women aged 40-49, 50-69 and 70-79 years were calculated. Changes in rates from a pre-screening period (1993-95) to a screening introduction phase (1996-2004) and then to a screening period (2005-08) are presented as hazard ratios comparing invited and non-invited women. Results: From the pre-screening period (1993-95) to the screening period (2005-08) the annual breast operation rate increased by 70% (HR=1.70 95% CI 1.62 to 1.78), from 180 to 305 per 100 000 women in the invited age group (50-69 years). In contrast, the increase was only 8% (HR=1.08 95% CI 1.00 to 1.16), from 133 to 144 per 100 000 women per year in the younger, non-invited age group (40-49 years) while an 8% decline (HR=0.92 95% CI 0.86 to 1.00), from 227 to 214 per 100 000 women per year occurred in the older, non-invited age group (70-79 years). In the screening period (2005-08) mastectomy rates fell similarly in invited and non-invited women. However, during the screening introduction phase (1996-2004) the mastectomy rate was 31% (HR=1.31 95% CI 1.20 to 1.43) higher in screened compared to non-screened younger age group. Annual mastectomy rates increased in invited from the pre-screening period to the screening introduction period from 156 to 167 per 100,000 women compared to a decline from 109 to 91 per 100,000 women in younger non-invited. Conclusions: Mammography service screening is associated with a marked increase in breast operation rates in the invited age group and also an increase in mastectomy rates. While overdiagnosis likely caused the initial increase in mastectomy rates and the overall increase in use of surgery in the age group subjected to screening, the more recent decline in mastectomy rates has affected all age groups and is likely to have been caused by changes in surgical policy.

Early evidence of increasing national mastectomy rates for the treatment of breast cancer.

136 Background: The use of mastectomy for the treatment of breast cancer has declined since initial randomized trials demonstrated equivalent survival with breast conservation therapy. Recent single institution series, however, have reported increasing mastectomy rates within the past decade. Methods: In order to verify these findings at the national level, we analyzed data from the Surveillance, Epidemiology, and End Results database, including women diagnosed with T1-2 N0-3 M0 breast cancer from 2000 to 2007. We evaluated therapeutic mastectomy rates by the year of diagnosis and performed a multivariable logistic regression analysis to determine predictors of mastectomy as the treatment choice. Results: A total of 228,240 patients met the entry criteria. The proportion of women treated with mastectomy decreased from 40.3% to 35.6% between 2000 and 2005. Subsequently, the mastectomy rate increased to 37.9% in 2007 (p &lt; 0.0001). The mastectomy rate in 2007 was the highest since 2002 (38.6%). A reversal in previously declining mastectomy rates was noted in nearly all cohorts, but was most pronounced among younger women. Multivariable analysis found that age, race, marital status, geographic location, involvement of multiple regions of the breast, lobular histology, increasing tumor size, lymph node positivity, increasing grade, negative hormone receptor status, and synchronous diagnosis of an ipsilateral or contralateral breast cancer were independent predictors of mastectomy. Additionally, multivariable analysis confirmed that women diagnosed in 2007 were more likely to undergo mastectomy than women diagnosed in 2005 (HR = 1.14, CI: 1.09 to 1.18, p &lt; 0.0001). Conclusions: There is evidence of a reversal in the previously declining national mastectomy rates, with the mastectomy rate reaching a nadir in 2005 and subsequently rising. Further follow-up to confirm this trend and investigation to determine the underlying cause of this trend and its impact on outcomes are warranted.

Effect of mammography screening on surgical treatment for breast cancer in Norway: comparative analysis of cancer registry data

Objective To determine the effect of mammography screening on surgical treatment for breast cancer.Design Comparative analysis of data from Norwegian cancer registry.Setting Mammography screening, Norway (screening of women aged 50-69...