Undergoing Breast Conservation Therapy Research Articles

Abstract PO3-20-05: Phase II Study of Genomically Guided Radiation Dose Personalization in the Management of Triple Negative Breast Cancer

Abstract Background: Our group has previously developed the radiosensitivity index (RSI) using a multigene expression model that is directly proportional to tumor radioresistance (high RSI = increased radioresistance). RSI has been previously validated in two datasets of patients with triple negative breast cancer (TNBC). In this study, we will run a selective dose personalization study in TNBC patients undergoing breast conservation therapy (BCT). Based on patients RSI scores, they will either receive a radiation therapy (RT) boost of 10 Gy to the tumor cavity or not. Given our data in two independent datasets, the current study will reveal the feasibility and benefit of selective genomic dose personalization in TNBC following BCT. Trial Design: The study is designed as a prospective, nonrandomized, phase II trial of genomically guided RT in the management of TNBC undergoing BCT. Patients will be allocated to one of two groups based on their RSI determination from fresh frozen tissue collected by biopsy or at the time of BCT. These groups will be Group A, RSI optimized whole breast radiotherapy alone or with a 10 Gy boost or Group B, RSI not optimized whole breast radiotherapy with a boost of 10 Gy to tumor cavity. Patients will receive standard of care chemotherapy, neoadjuvant or adjuvant. Eligibility: TNBC patients undergoing BCT. Specific Aims: To determine the three-year local control following genomically guided dose personalization in the management of TNBC following BCT. Secondary objectives include determination of overall survival (OS), progression free survival (PFS), and quality of life (QOL) following genomically guided dose personalization. Statistical Methods: The primary hypothesis is the three-year local control rates differ for groups A and B, against the null hypothesis that the two rates are identical. Patients will allocate approximately 78% in group A and 22% in group B and local control rates are expected to be 96% and 75%, respectively. Assuming 80% power and 10% type I error for a log-rank test, 86 patients are needed. An interim analysis will be completed when 4 disease progression events are observed. There will be approximately 43 patients at the time of interim analysis. Patient Accrual: This study is open with 1 patient enrolled at the time of submission. A total of 86 patients will be enrolled. Contact Information: Kamran A. Ahmed MD, Moffitt Cancer Center, email: kamran.ahmed@moffitt.org, Clinical trial information: NCT05115474. Funding: Moffitt and Morton Plant Mease Foundations. Citation Format: Kamran Ahmed, Iman Washington, Matthew Mills, Michelle DeJesus, Youngchul Kim, Ronica Nanda, Javier Torres-Roca, Steven Eschrich, Janis De La Iglesia, John Puskas, Marilin Rosa, Jason Wilson, Paula Lundgren, Negar Golesorkhi, Nazanin Khakpour, Susan Hoover, Marie Lee, John Kiluk, Melissa Mallory, Christine Laronga, Laura Kruper, Brian Czerniecki, Roberto Diaz. Phase II Study of Genomically Guided Radiation Dose Personalization in the Management of Triple Negative 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 PO3-20-05.

Reappraisal of an Adequate Negative Margin Following Breast Conservation Therapy in Young Patients with Invasive Breast Cancer

This study aimed to examine the relationship between resection margin (RM) width and ipsilateral breast tumor recurrence (IBTR). The current definition of an adequate negative margin was validated in young breast cancer patients (<40 years). This study included 4,042 patients who underwent breast conservation therapy between 2006 and 2012. There were 595 women <40 years (14.7%). Re-excision to achieve a wider RM was not considered in patients with no ink on tumor. Systemic treatments were administered in 3,985 patients (98.6%). The impact of RM width on the incidence of IBTR was assessed using narrowly specified intervals (positive, >0 to <1 mm, 1 to <2 mm, 2 to <3 mm, and ≥3 mm). A significant relationship was observed between RM width and incidence of IBTR. In young women, the 10-year cumulative incidence rates of IBTR were 21.6% for positive RM, 13.9% for >0 to <1 mm, 10.9% for 1 to <2 mm, 5.7% for 2 to <3 mm, and 5.8% for ≥3 mm (p <0.01). The corresponding incidence rates of IBTR in women ≥40 years were 8.6%, 8.0%, 4.4%, 2.7%, and 2.1%, respectively (p <0.01). The difference in the incidence of IBTR between each RM width interval increased over time, and the magnitude of the increment was greater in young women. RM width was the only risk factor for IBTR in young women. The relationship between RM width and IBTR was definite in young women. Compared with women ≥40 years, young women might have long-term benefits from a wider RM than no ink on tumor.

Abstract P4-07-52: Caloric Restriction for Oncology Research (CaReFOR): Assessing dietary adherence and outcomes in African American patients during breast cancer treatment

Abstract Purpose: Epidemiologic and clinical evidence have shown an association between obesity and increased risk for breast cancer (BC) incidence and mortality. Data from human and animal studies support a potential role for weight loss in counteracting tumor-promoting properties of obesity in BC. However, dietary intervention clinical trials often show low patient adherence, especially among African American (AA) women compared to Caucasian (CC) women. They also show that AA women are disproportionately obese and lose less weight during behavior lifestyle interventions compared to CC with similar risk factors. We evaluated the efficacy and feasibility of a 10-week caloric restricted diet in patients undergoing radiation and have performed analysis to determine if adherence to dietary alterations is feasible in underrepresented patients. Methods: In an IRB approved clinical trial, we determined the feasibility and toxicity of dietary intervention during radiation in breast cancer patients 18 years and older who were undergoing breast conservation therapy with T1-2N0 cancers. The dietary intervention consisted of caloric intake reduction of 25% from baseline for a total of 10 weeks during their six-week radiation treatment which was administered to the whole breast to a dose of 50Gy with a 10Gy boost to the tumor bed. To optimize adherence to caloric restriction (CR), patients received personalized counseling, maintained food diaries, and were educated on behavioral modifications at weekly visits. To characterize the effects of CR, baseline physiologic and blood parameters were collected and compared with post intervention measurements and samples. Biometric and biological data collected during the study comparing compliant participants before and after the CaReFOR intervention was stratified by race and analyzed via two-sample paired t-test. The difference between AA and CC study participants was determined to be significant if the calculated p-value was less than &amp;lt; 0.05 (CI 95%). Results: A total of 32 female patients were enrolled in the CaReFOR trial, 16 were AA and 16 were CC. Participant demographics were similar across age, primary tumor size (pT), nuclear grade, and hormone receptor status. Evaluation of patients’ baseline diet demonstrated similar macronutrients across races, with AA showing less fruit/vegetable and grains. AA patients were more overweight compared to their CC counterparts. They also showed a more inflamed state compared to CC patients. The baseline inflammatory biomarker levels for ESR and cholesterol were significantly higher while adiponectin was significantly lower in AA than that of CC patients. The trends for insulin, HbA1c, and leptin were also higher for AA compared to CC. Following the 10-week diet, AA patients (87.3%) were more compliant than CC’s (81.3%). Both AA and CC patients lost weight during the trial, with AA having a significant loss in body fat and gain in muscle mass compared to CC. Similarly, after completing the CR diet, biological inflammatory markers improved in AA and CC patients. Particularly, in AA, there was a significant decrease in cholesterol levels, while insulin, leptin, and ESR serum levels trended downwards, suggesting a decreased inflammatory state. Conclusions: Contrary to published studies, we found AA patients are successful in adhering to dietary alterations and have a benefit with respect to physiologic and biologic parameters. Our dietary intervention was able to positively affect our AA patients adverse baseline factors such as obesity and inflammation. Future studies should consider dietary alterations as a possible means to decrease AA patient disparate outcomes in breast cancer. Citation Format: Siani Harding, Adeseye Adekeye, Edith P. Mitchell, Nicole Simone. Caloric Restriction for Oncology Research (CaReFOR): Assessing dietary adherence and outcomes in African American patients during breast cancer treatment. [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P4-07-52.

Multimodality Imaging Review of HER2-positive Breast Cancer and Response to Neoadjuvant Chemotherapy

Human epidermal growth factor receptor 2 (HER2/neu or ErbB2)-positive breast cancers comprise 15%-20% of all breast cancers. The most common manifestation of HER2-positive breast cancer at mammography or US is an irregular mass with spiculated margins that often contains calcifications; at MRI, HER2-positive breast cancer may appear as a mass or as nonmass enhancement. HER2-positive breast cancers are often of intermediate to high nuclear grade at histopathologic analysis, with increased risk of local recurrence and metastases and poorer overall prognosis. However, treatment with targeted monoclonal antibody therapies such as trastuzumab and pertuzumab provides better local-regional control and leads to improved survival outcome. With neoadjuvant treatments, including monoclonal antibodies, taxanes, and anthracyclines, women are now potentially able to undergo breast conservation therapy and sentinel lymph node biopsy versus mastectomy and axillary lymph node dissection. Thus, the radiologist's role in assessing the extent of local-regional disease and response to neoadjuvant treatment at imaging is important to inform surgical planning and adjuvant treatment. However, assessment of treatment response remains difficult, with the potential for different imaging modalities to result in underestimation or overestimation of disease to varying degrees when compared with surgical pathologic analysis. In particular, the presence of calcifications at mammography is especially difficult to correlate with the results of pathologic analysis after chemotherapy. Breast MRI findings remain the best predictor of pathologic response. The authors review the initial manifestations of HER2-positive tumors, the varied responses to neoadjuvant chemotherapy, and the challenges in assessing residual cancer burden through a multimodality imaging review with pathologic correlation. © RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.

The Impact of Oncoplastic Reduction on Initiation of Adjuvant Radiation and Need for Reexcision: A Database Evaluation.

Partial breast reconstruction with oncoplastic reduction can provide breast cancer patients with improved aesthetic outcomes after breast conservation therapy. This study evaluates the implications of simultaneous oncoplastic reduction with lumpectomy on complication rates, time to adjuvant radiation therapy, and rates of margin reexcision compared with lumpectomy alone. The Clinformatics Data Mart Database is a national deidentified commercial claims data warehouse. From 2003 to 2020, adult female patients were queried to identify patients with a breast cancer diagnosis with International Classification of Disease codes. Among those, current procedural terminology codes were used to identify those who underwent lumpectomy alone versus lumpectomy with oncoplastic reduction. Patient demographics, complications, adjuvant oncologic therapies, and need for reexcision were recorded. Patients not continuously enrolled for at least 6 months before and after the index procedure were excluded. Multivariable regression and χ 2 tests were used for statistical analysis. Of 53,165 patients meeting criteria (mean age, 61.4 ± 11.6 years), 1552 (2.9%) underwent oncoplastic reduction. Diagnoses of most nonsurgical complications (seroma, wound dehiscence, postoperative infection, fat necrosis, tissue necrosis, and nonspecified complications of surgical care) were significantly higher in the oncoplastic reduction group, as were rates of some surgical complications (hematoma, seroma, and tissue debridement). However, undergoing oncoplastic reduction did not impact time to adjuvant radiation ( P = 0.194) and protected against positive margins requiring repeat lumpectomy or completion mastectomy ( P < 0.001). In patients undergoing breast conservation therapy, simultaneous oncoplastic reduction decreased occurrence of positive margins and did not impact time to adjuvant radiation therapy despite increased rates of surgical and nonsurgical complications.

Comparing oncoplastic breast reduction with immediate symmetry surgery to standard breast reduction surgery: Are postoperative complications worse?

Oncoplastic breast reduction mammoplasty (ORM) is an excellent treatment option for women with breast cancer and macromastia undergoing breast conservation therapy. Here, we aim to better understand the risks associated with ORM compared to standard reduction mammoplasty (SRM). A retrospective chart review was performed of patients undergoing ORM or SRM from 2015 to 2021. Primary outcomes included the occurrence of major or minor postoperative complications in the two groups and delays to adjuvant therapy (>90 days) among the women undergoing ORM. Women in the ORM group (n = 198) were significantly older (p < 0.001) with a higher prevalence of smoking (p < 0.001), diabetes mellitus (p < 0.01), and a Charlson comorbidity index ≥ 3 (p < 0.001) compared to women undergoing SRM (n = 177). After controlling for potential confounders, there were no significant between-group differences in the odds of developing postoperative complications (odds ratio = 0.80, 95% confidence interval: 0.36-1.69). Only 3% (n = 4) of the 150 women undergoing adjuvant radiation or chemotherapy experienced delays related to postoperative complications. ORM has a similar safety profile as SRM, despite the older age and higher number of comorbidities often seen in patients undergoing ORM, and is a safe option for achieving contralateral symmetry at the time of partial mastectomy without delays to adjuvant therapy.

123. The Impact of Oncoplastic Reduction on Initiation of Adjuvant Radiation and Need for Re-excision: A Database Evaluation

Purpose: Partial breast reconstruction with oncoplastic reduction can provide breast cancer patients with improved aesthetic outcomes following breast conservation therapy. This study evaluates the implications of simultaneous oncoplastic reduction with lumpectomy on complication rates, time to adjuvant radiation therapy, and rates of margin re-excision compared to lumpectomy alone. Methods: The Clinformatics® Data Mart Database is a national deidentified commercial claims data warehouse. From 2003-2020, adult female patients were queried with International Classification of Disease (ICD-9 and ICD-10) codes to identify patients with a breast cancer diagnosis. Among those, common procedural terminology (CPT) codes were used to identify those who underwent lumpectomy alone versus lumpectomy with oncoplastic reduction. Patient demographics, complications, adjuvant oncologic therapies, and need for re-excision were recorded. Patients who were not continuously enrolled for at least six months before and after the index procedure were excluded. Chi squared and multivariable regression tests were used for statistical analysis. Results: Of 53,165 patients meeting criteria (mean age 61.4 ± 11.6 years), 1,552 (2.9%) underwent oncoplastic reduction. Diagnoses of most non-surgical complications (seroma, wound dehiscence, postoperative infection, fat necrosis, tissue necrosis, and non-specified complications of surgical care) were significantly higher in the oncoplastic reduction group, as were rates of some complications requiring surgical intervention (hematoma, seroma, and tissue debridement). However, undergoing oncoplastic reduction did not have an impact on time to adjuvant radiation (p=0.187) and protected against positive margins requiring repeat lumpectomy or completion mastectomy (p less than 0.001). Conclusion: In patients undergoing breast conservation therapy, simultaneous oncoplastic reduction decreased occurrence of positive margins and did not impact time to adjuvant radiation therapy, despite increased rates of surgical and non-surgical complications.

A comparison of timely completion of hypofractionated and traditional adjuvant radiation therapy in early-stage breast cancer: Evidence of impact on reducing racial and socioeconomic disparities

BackgroundTimely completion of adjuvant radiation after breast conservation therapy is associated with decreased mortality and increased disease-free survival. Few data exist comparing timely completion between hypofractionated radiation and traditional radiation at a national level or across racial and socioeconomic cohorts. MethodsA retrospective review of the National Cancer Database (2012–2016) on patients undergoing breast conservation therapy for early-stage breast cancer, specifically T1 or T2, N0, M0 patients, was performed. Multivariable logistic regression models were used to compare timely completion of hypofractionated radiation (within 5 weeks of initiation) and traditional radiation (within 7 weeks) across patient, tumor, and facility characteristics. ResultsIn total, 210,816 patients met criteria, with 59.4% receiving traditional radiation (n = 125,140) and 40.6% receiving hypofractionated radiation (n = 85,676). Overall, 82.8% of patients achieved timely completion of radiation. Among hypofractionated radiation patients, 94.5% of patients achieved timely completion, whereas only 74.8% of traditional radiation patients achieved timely completion (P < .0001). Regarding race/ethnicity, all groups benefited substantially in timely completion of hypofractionated radiation over traditional radiation. However, both treatment cohorts demonstrated that Black (odds ratio (hypofractionated radiation) = 0.842, odds ratio (traditional radiation) = 0.821) and Hispanic (odds ratio (hypofractionated radiation) = 0.917, odds ratio (traditional radiation) = 0.907) patients had lower odds of timely completion compared to White patients (P < .0001). Lower high school graduation rate, median income for patients’ ZIP code, and Medicaid were also associated with lower odds of timely completion for both hypofractionated radiation and traditional radiation (both P < .0001). ConclusionTimely completion of radiation therapy in breast conservation therapy is greater for patients receiving hypofractionated radiation than traditional radiation across racial and socioeconomic cohorts. Disparities in timely completion were substantially reduced with hypofractionated radiation utilization. However, there are treatment disparities across racial and socioeconomic cohorts that persist in both treatment groups.

Choice of Mastectomy May Increase the Extent of Axillary Surgery in Women with Breast Cancer

Based on the ACOSOG Z0011 trial, women who undergo breast conservation therapy (BCT) and have limited disease in the axilla on sentinel lymph node (SLN) biopsy do not require axillary lymph node dissection (ALND). In this study we investigate the incidence of ALND in patients undergoing elective mastectomy with limited disease in the axilla to identify how many women may have been spared additional axillary surgery if they chose BCT. All women with invasive breast cancer treated at a single tertiary care breast center from 2010-2018 who were candidates for BCT but elected mastectomy and underwent SLN biopsy were identified through retrospective review of a prospectively maintained database. The primary outcome of interest was the incidence of ALND in women found to have a limited burden of disease in the axilla (1-2 positive SLNs). The study population comprised 151 patients with invasive breast cancer eligible for BCT who chose mastectomy. On final pathology, 34 patients had 1-2 positive SLNs, and 16 of these patients underwent completion ALND. These 16 patients out of 151 overall lumpectomy candidates electing mastectomy (10.6%) could have been spared ALND if they did not elect mastectomy. BCT candidates electing mastectomy have a 10.6% chance of undergoing more extensive axillary surgery than would have been recommended with BCT alone. The increased risk of undergoing additional axillary surgery should be incorporated into the preoperative discussion for patients choosing between BCT and mastectomy.

Study of Clinical Profile and Management of LABC- our Experience

Introduction and Objective: Worldwide, breast carcinoma is among the most common carcinoma in females. It is commonly seen site-specific carcinoma in females. Due to lack of education, breast carcinoma patients present in later stages of the disease to healthcare facilities, especially in developing nations. Patients with Locally advanced carcinoma breast (LABC) are commonly seen in developing nations and its treatment multidisciplinary approach. This study is our experience of clinical profile and LABC in a rural setup.&#x0D; Methodology: This is a retrospective and prospective study done in the medical college. Data was taken from 72 cases that were operated on at the institute from July 2018 to June 2021 and diagnosed with LABC. Patients who had histological evidence of malignancy were undergone surgery and other treatment modalities like neoadjuvant chemotherapy, adjuvant chemoradiation, and hormonal therapy.&#x0D; Results: Seventy-two patients diagnosed with LABC over three years were included in the study. The mean age was 51 years. The tumor size was more than 5cm in 60 (83.3%) patients. Involvement of axilla was present in 62 (86.1%) patients. All patients were diagnosed with histopathology after core needle biopsy. Neoadjuvant chemotherapy was given to 62 (86.1%) patients. Most of the patients (65) were undergone MRM as surgery, while the remainder (7) were undergone breast conservation therapy. Very few patients had postoperative complications, but with limited follow-up until this study, 5 (6.9%) patients had a recurrence of their study.&#x0D; Conclusion: In developing nations high percentage of Locally advanced breast carcinoma at presentation result in poor prognosis, high rate of metastasis, and mortality. Awareness and education about breast health and multimodality treatment of LABC will have long-term effects to decrease morbidity and mortality and improve outcomes.

EP.TH.531Occult breast cancer: Breast conservation or Mastectomy in terms of recurrence. A single center experience

Abstract Aim We sought to compare breast conservation therapy &amp; mastectomy as treatment of occult breast cancer in terms of recurrence. Methods It is a retrospective cross sectional study conducted on patients diagnosed to have occult breast cancer and going for either breast conservation therapy or mastectomy at The Aga Khan University Hospital Karachi between January 200o to December 2018, patients will be divided into two groups, first group will be consisting of patients who underwent breast conservation therapy and 2nd one will be of patients who had mastectomy. Patients will be included by consecutive sampling technique. Hospital database will be used to identify patients and data collected on a self designed tool using files and electronic patient records. Patients in both groups will be followed to see local recurrence from date of diagnosis to 2 years post operatively in hospital data base and their files, and then their data will be compared with the reference studies reported in this article. Results Awaited as the study is ongoing. Conclusions Awaited as study is ongoing.

A Pilot Study to Quantify Breast Lymphedema for Patients Undergoing Breast Conserving Therapy (BCT) for Breast Cancer

<h3>Purpose/Objective(s)</h3> Upper extremity lymphedema after axillary lymph node dissection and radiation for breast cancer has been well described and studied. As modern treatment techniques have reduced the incidence of arm lymphedema, breast lymphedema has emerged as a common result of BCT and is associated with poor wound healing, infection and impact on quality of life. Because there is no established tool for its evaluation and quantification, we explored the feasibility of using ultrasound to measure breast lymphedema objectively. We evaluated whether this measure correlated with clinical assessment, treatment factors, and patient-reported outcomes. <h3>Materials/Methods</h3> We enrolled 30 women with malignant breast cancer treated with breast conserving surgery, sentinel lymph node biopsy, and breast radiation. Another 10 women with benign disease who had not undergone BCT were sampled as controls. Ultrasound measurements of dermal thickness were performed on the treated breast and untreated breast at the 6:00 position. Post-treatment assessments included physical exam and quality of life DASH questionnaire. We quantified breast lymphedema as the dermal thickness of the affected breast minus the dermal thickness of the unaffected breast. Breast lymphedema was considered present if dermal thickness difference was above the highest-observed value in the benign patients. <h3>Results</h3> Mean age (± SD) was SD 59 ± 13 in the malignant group and 46.4 ± 17 in the benign group and groups were similar with regard to body mass index. Mean dermal thickness difference was higher in the malignant group compared with the benign group (1.03 mm and 0 mm, respectively). Seventy percent of patients in the malignant group met our definition of breast lymphedema (n = 21) and were more likely to report impact on quality of life pertaining to sexual activity (24% vs 11%), breast sensation (52% vs 16%), sleep quality (33% vs 21%) and confidence (24% vs 5%) than patients without breast lymphedema. Extent of axillary surgery was associated with a 1.29 mm increase in difference in dermal thickness for patients with > = 4 nodes removed (95% CI: -0.22, 2.80). The volume of breast tissue radiated was also positively associated, with every 100cc increase in breast volume radiated associated with a 0.17mm greater dermal thickness difference (95% CI: 0.04, 0.30mm). However, there was no association with percent of breast tissue receiving > 105% of prescribed dose (95% CI: -0.07, 0.01), hypofractionation vs. standard fractionation (95% CI: -1.2, 0.68) or total radiation dose (95% CI: -0.5, 1.2). <h3>Conclusion</h3> Breast lymphedema is an impactful sequela of breast cancer treatment but remains understudied with no standard measurement tools. Our pilot study demonstrates that ultrasound is a promising tool for the characterization of breast lymphedema and may improve our understanding of patient and modifiable treatment risk factors.

Usefulness of postoperative surveillance MR for women after breast-conservation therapy: Focusing on MR features of early and late recurrent breast cancer.

PurposeTo investigate the imaging characteristics of early and late recurrent breast cancer and the detectability of mammography, ultrasonography, and breast magnetic resonance imaging (MRI) in patients who underwent breast-conservation therapy (BCT).Materials and methodsTotal of 1312 women with 2026 surveillance breast MRI after BCT between January 2014 and September 2018 were studied. Early recurrence was defined as newly diagnosed breast cancer and/or axillary metastasis within 12 months of surgery. Late recurrence was defined as recurrence after 12months of surgery. We assessed the detectability of recurrent lesions in each postoperative imaging modality and evaluated characteristics of recurrent lesions on postoperative MRI by comparing early and late recurrence groups.ResultOf the 2026 cases, 103 were confirmed as recurrent breast cancer by biopsy or surgery. Thirty-one cases were early recurrence, and 72 cases were late recurrence. MRI showed significantly higher detectability for recurrent lesions (102 cases, 99%) than mammography (59.4%, p < 0.001) or ultrasound (68.9%, p < 0.001), or both mammography and ultrasound (81.6%, p < 0.001). The recurrent lesions did not have typical malignant morphologic features, but variable features on MRI. However, early recurrent lesions showed fast enhancement in early dynamic phase regardless of the kinetic pattern of delayed dynamic phase; and late recurrence lesions showed early fast enhancement and delayed washout pattern. There were 19 cases which were not detected on mammography or ultrasound but could only be detected with MRI.ConclusionPostoperative breast MRI showed significantly higher detectability for recurrent lesions than mammography and ultrasound. Early fast enhancement is the most important feature of recurrent lesions on postoperative breast MRI for both early and late recurrence groups. Due to its high possibility of recurrence, further work-up should be considered regardless of their morphologic features.

Can We Avoid Axillary Lymph Node Dissection (ALND) in Patients with 1-2 Positive Sentinel/Low Axillary Lymph Nodes (SLN/LAS+) in the Indian Setting?

The ACOSOG Z0011 study, heralded as a "practice changing" trial, suggested that women with T1-2 breast cancer with 1-2 SLN+, undergoing breast conservation therapy, need not be offered further ALND. However, whether these results are applicable to all women in the Indian setting, it remains debatable. A retrospective audit of all cN0 operated from 2013 to 2018 was conducted. We analyzed the percentage of additional LN positive (LN+) in the ALND group and compared it to the ACOZOG Z11 trial. Of the 2350 cN0 with EBC who underwent LAS, 687 (29%) had positive lymph nodes on final histopathology. Five hundred ninety-seven (86.9%) patients had 1-2 LN+, 40 (5.8%) patients had 3 LN+, and 50 (7.3%) had 4 or more nodes positive. Demographic features in the ACOSOG Z11 are different from those in our study, looking at ACOZOG Z11 versus our cohort-median pT 1.7cm versus 3cm, 45% micrometastasis versus 99.16% macrometastasis, and 28-30% grade 3 tumors versus 73.7%. In our cohort 31.82% of the 1-2 LN positive had additional LN+ on ALND. Keeping in mind the difference in clinicopathological features between our cohort and that of ACOZOG Z0011 and that 31.82% of women had additional LN+ on ALND, it may not be appropriate to apply the results of the ACOSOG Z0011 trial directly to our general population. Possibly, only a select subset of patients who match the trial population of the ACOSOG Z11 could be offered observation of the axilla and validated nomograms can be used to identify high-risk patients.

Impact of lobular carcinoma in situ on local recurrence in breast cancer treated with breast conservation therapy: a systematic review and meta‐analysis

Lobular carcinoma in situ (LCIS) is a known risk factor for breast cancer of unclear significance when detected in association with invasive carcinoma. This meta-analysis aims to determine the impact of LCIS on local recurrence risk for individuals with breast cancer treated with breast conservation therapy to help guide appropriate management strategies. We identified relevant studies from five electronic databases. Studies were deemed suitable for inclusion where they compared patients with invasive breast cancer and concurrent LCIS to those with breast cancer alone, all patients underwent breast conservation therapy (lumpectomy with adjuvant radiation therapy) and local recurrence was evaluated. Recurrence data were pooled by use of a random-effects model. From 1488 citations screened by our search, nine studies were deemed suitable for inclusion. These studies comprised 990 cases and 12 870 controls. Median follow-up time was 104 months. There was a significantly increased risk of overall local recurrence of breast cancer for individuals with LCIS in association with breast cancer following breast conservation therapy (pooled odds ratio (pOR) 1.73; 95% confidence interval (CI) 1.10-2.71; P=0.018). The risk of local recurrence was not significantly increased at 5 years (pOR 1.00; 95% CI 0.49-2.04; P=0.995) and 10 years (pOR 1.52; 95% CI 0.72-3.23; P=0.275). Individuals with LCIS in association with invasive breast cancer have an increased risk of local recurrence following breast conservation therapy. This supports consideration of increased medical surveillance and exploration of further risk reduction strategies for such patients.

Abstract PS1-12: Factors associated with chronic breast lymphedema after adjuvant radiation in women undergoing breast conservation therapy

Abstract Purpose/Objective(s):Unlike temporary breast edema caused by post-lumpectomy radiation therapy (RT), the edema that persists beyond one year is not well defined and difficult to treat. The aim of this study is to define the incidence and risk factors for the development of chronic breast lymphedema in women undergoing lumpectomy with RT at a large metropolitan cancer center. Materials/Methods:A retrospective chart review was performed on all patients who underwent lumpectomy from 2014 to 2018. Women who did not undergo RT at our institution and those with stage IV disease were excluded from the analysis. Patient demographics, comorbidities, operative data, RT data and postoperative complications were obtained. Chronic breast lymphedema (CBL) was defined as edema that persisted beyond one year post completion of radiation therapy. Breast volumes were determined by contoured breast volumes or, if unavailable, estimated by the 95% isodose volumes from the RT treatment planning system. Using a density curve, the distribution of breast volumes was plotted for patients with and patients without CBL. Univariate analysis was used to evaluate factors associated with CBL. Multivariate regression analysis was used to evaluate factors associated with the risk of CBL while accounting for potential confounding variables as defined by the univariate analysis. Results:A total of 1173 patients were included for analysis. Seventy-four (6.3%) patients developed breast lymphedema beyond one year. For the entire cohort, mean age was 63 years old (SD=11.17), mean BMI was 31.15 kg/m2 (SD=7.17), mean breast volume was 1198.54 cm3 (SD=645.82 cm3), mean total radiation was 59.18 Gy (SD=16.76), and 139 (11.8%) patients underwent ALND. Compared to the cohort that did not develop CBL (n=1099), the CBL cohort (n=74) had a higher median BMI (33.23 kg/m2 vs. 29.81 kg/m2, P&amp;lt;0.001), higher percentage of African Americans (56.8% vs. 37.9%, P=0.004), larger median breast volume (1502.33 cm3 vs. 1083.59 cm3, P&amp;lt;0.001), higher percentage that underwent ALND (23% vs. 11.1%, P=0.005), and larger median size of lumpectomy specimen (128.00 cm3 vs. 94.57 cm3, P=0.002). When accounting for potential confounding variables, multivariate regression analysis revealed when breast volume was evaluated as a continuous variable, for every 1 cm3 increase in breast volume, the risk of breast lymphedema increases by 0.1% (OR=1.001, P&amp;lt;0.001). When breast volume was analyzed as a categorical variable using 1300 cm3 as the optimal cutoff (based on density curve evaluations), patients whose breast volume was greater than 1300 cm3 had nearly 3 times the risk of developing CBL (OR=2.976, P&amp;lt;0.001) compared to those with less than 1300 cm3 breast volume. The multivariate regression also demonstrated that CBL was associated with total radiation dose (OR=1.02, P=0.015) and African American race (OR=1.705, P=0.037). Conclusion:Chronic breast lymphedema presents a clinical concern for women undergoing lumpectomy with postoperative radiation, particularly in women with larger breasts. Further studies should focus on preventative strategies, as well as the psychosocial and economic impact of this morbidity. Citation Format: Sanjay Rama, Cara Canella, Jenna Luker, Kelley Park, Renee Barry, Saheli Ghosh, Simeng Zhu, Yalei Chen, Jessica Bensenhaver, Eleanor Walker, Kenneth Levin, Dunya Atisha, Maristella Evangelista. Factors associated with chronic breast lymphedema after adjuvant radiation in women undergoing breast conservation therapy [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 PS1-12.

Combined Photothermal and Ionizing Radiation Sensitization of Triple-Negative Breast Cancer Using Triangular Silver Nanoparticles.

BackgroundIonizing radiation (IR) is commonly used in triple-negative breast cancer (TNBC) treatment regimens. However, off-target toxicity affecting normal tissue and grueling treatment regimens remain major limitations. Hyperthermia is one of the greatest IR sensitizers, but only if heat is administered simultaneously or immediately prior to ionizing radiation. Difficulty in co-localizing ionizing radiation (IR) in rapid succession with hyperthermia, and confining treatment to the tumor have hindered widespread clinical adoption of combined thermoradiation treatment. Metal nanoparticle-based approaches to IR sensitization and photothermal heat generation may aid in overcoming these issues and improve treatment specificity.MethodsWe assessed the potential to selectively treat MDA-MB-231 TNBC cells without affecting non-malignant MCF-10A breast cells using a multimodal approach based upon combined photothermal therapy, IR sensitization, and specific cytotoxicity using triangular silver nanoparticles (TAgNPs) with peak absorbance in the near-infrared light (NIR) spectrum.ResultsWe found that TAgNP-mediated photothermal therapy and radiosensitization offer a high degree of specificity for treatment of TNBC without affecting non-malignant mammary epithelial cells.DiscussionIf given at a high enough dose, IR, heat, or TAgNPs alone could be sufficient for tumor treatment. However, when the dose of one or all of these modalities increases, off-target effects also increase. The challenge lies in identifying the minimal doses of each individual treatment such that when combined they provide maximum selectivity for treatment of TNBC cells with minimum off-target effects on non-malignant breast cells. Our results provide proof of concept that this combination is highly selective for TNBC cells while sparing non-malignant mammary epithelial cells. This treatment would be particularly important for patients undergoing breast conservation therapy and for treatment of invasive tumor margins near the periphery where each individual treatment might be at a sub-therapeutic level.

Superparamagnetic Iron Oxide Sentinel Node Tracer Injection: Effects on Breast MRI Quality.

To evaluate the MRI artifact rendered by the typical injection of a ferromagnetic tracer now being intermittently used for intraoperative sentinel node (SN) identification at our institution, and to explore its impact on postoperative imaging and management. This study was Institutional Review Board-approved and granted a waiver of consent. A database search tool was used to identify MRI exams performed on patients who had previously undergone breast-conserving surgery with use of a superparamagnetic iron oxide (SPIO) SN tracer between January 1, 2015, and May 1, 2020. MRI reports, images, and relevant demographic, oncologic, and surgical history were collected. The presence or absence of SPIO residue on breast MRI, as well as its impact on image quality, were extracted from the prospective reports. A total of 21 MRI exams were identified in 16 patients who had undergone breast-conservation therapy for cancer with use of SPIO SN tracer. Mean time from particle injection to baseline postoperative MRI exam was 10.8 months. All reports (21/21) noted evidence of SPIO residue. Of these, 5/21 were assessed as non-diagnostic; the remainder were assessed as limited. Radiologists should be aware of the use of superparamagnetic tracers for SN identification and the impact on the quality of future MRI examinations. Alternative injection approaches are being developed and sequence parameters adjusted to minimize artifact.

Outcome of Treatment After Locoregional Radiation, Neoadjuvant and Adjuvant Chemotherapy for Breast Cancer

The addition of systemic therapy to locoregional treatment for women with all stages of breast cancer improves survival. Reliable data are lacking about the outcomes of women with breast cancer in low-middle income countries who are treated with a combination of radiotherapy (RT), surgery, and systemic therapy. report the outcome of women with breast cancer treated with either neoadjuvant chemotherapy (NACT) or adjuvant chemotherapy at the National Centre for Radiotherapy and Nuclear Medicine in Accra, Ghana. The medical charts of all women with breast cancer managed at the National Centre for Radiotherapy and Nuclear Medicine from 2005 to 2014 were reviewed. Available patient specific demographic data, tumor stage, treatment sequence, and follow-up information were recorded. Logistic regression was used to estimate the presence of locoregional (LRR) and distant recurrence (DR) between two chemotherapy groups. Overall survival (OS) and disease-free survival (DFS) were used as time dependent outcomes and were analyzed using cox proportional hazard (CPH) model. All the models were adjusted with clinico-pathologic variables and estimates were reported along with their 95% confidence interval (CI). A total of 387 patients with a median follow up of 48 months were included in the study. The median age at diagnosis was 51 years. 49.6% of women had advanced pathologic stage ≥pT3. 58.9% (n = 228) received adjuvant chemotherapy whereas 41.1 % (n = 159) received NACT. The majority of women (94.1%, n = 365) received RT. 18.4% (n = 67) underwent breast conservation therapy followed by RT to a mean dose of 48.8 Gy in 10-30 fractions, and 81.6% (n = 298) had a mastectomy followed by RT to a mean dose of 47.92 Gy in 10-30 fractions. In an adjusted logistic model, no difference was observed in LRR between patients receiving NACT compared to those receiving adjuvant chemotherapy (OR = 1.05, 95% CI {0.44 - 2.47}, p = 0.9). However, NACT recipients had a higher likelihood of DR (OR = 1.97, 95% CI, {1.24 – 3.15}, p = 0.004). In a multivariate analysis, no differences were observed in survival between the two chemotherapy groups (HR = 1.43, 95% CI, {0.91 – 2.26}, p = 0.1). There was a trend towards lower DFS within the NACT group compared to the adjuvant chemotherapy group, with patients receiving NACT having a 52% likelihood of lower DFS (HR = 1.52, 95% CI, {0.96 – 2.39}, p = 0.06). While many women present with late stage disease in Ghana, outcomes after trimodal therapy are comparable to what is observed in developed countries. Advanced stage of disease is significantly associated with recurrence and survival, hence early detection in a resource limited setting is crucial to optimal outcomes. To our knowledge, this is the first and largest study to report on the outcomes of women with breast cancer who receive standard of care treatment in Ghana.

Factors Associated with Chronic Breast Lymphedema After Adjuvant Radiation in Women Undergoing Breast Conservation Therapy

Factors Associated with Chronic Breast Lymphedema After Adjuvant Radiation in Women Undergoing Breast Conservation Therapy