Undergoing Breast Conservation Research Articles

Frank Invasion in Tall Cell Carcinoma with Reversed Polarity of the Breast: Report of Two Cases.

Tall cell carcinoma with reversed polarity (TCCRP) is a rare neoplasm of the breast composed of columnar tumor cells arranged in solid and solid papillary nests with evidence of apical nuclear polarity. No frank invasion is evident despite the lack of a myoepithelial cell layer throughout the tumor. TCCRP has a triple negative or hormone receptor-low immunophenotype. Recurrent IDH2 R172 hotspot mutation coexisting with genetic alterations in the PI3K pathway characterize this tumor. Here, we report on two postmenopausal patients with TCCRPs with frank stromal invasion. IDH2 R172 mutations were detected in both tumors by immunohistochemistry. Targeted sequencing of case 2 demonstrated the presence of IDH2 R172T and RTEL1 E839K mutations. Both patients underwent breast conservation surgery, radiation therapy and adjuvant endocrine therapy with anastrozole and show no evidence of disease at 65 and 25 months, respectively. This study suggests that tall cell carcinoma with reversed polarity may give rise to frank invasive carcinoma, the prognostic significance of which is yet unknown.

Factors associated with breast lymphedema after adjuvant radiation therapy in women undergoing breast conservation therapy

PurposeBreast lymphedema after post-lumpectomy radiation therapy (RT) is poorly defined and difficult to treat. The aim of this study was to define the incidence of breast lymphedema and identify factors associated with the risk of developing breast lymphedema (BL) in women undergoing breast-conserving therapy. MethodsA retrospective cohort study of patients with early-stage breast cancer who underwent breast-conserving surgery (lumpectomy) followed by RT between January 1, 2014 and July 31, 2019 at a single institution. Women who developed BL, defined as swelling of the breast persisting ≥1 year after RT, were compared with women who did not. Univariate and multivariate regression analyses were used to identify factors associated with risk of BL. ResultsA total of 1052 patients were included in the study: 99 (9.6 %) developed BL and 953 (90.6 %) did not develop BL. The mean ± standard deviation age was 62.9 ± 11.1 years and the mean breast volume was 1352.0 ± 744.9 cm3. Patients with breast volume ≥1500 cm3 (adjusted odds ratio [aOR] = 2.34; 95 % CI, 1.40–3.91; p = 0.001), Black patients (aOR = 1.78; 95 % CI, 1.12–2.82; p = 0.015), those who received neoadjuvant (aOR = 3.05; 95 % CI, 1.28–7.30; p = 0.012) or adjuvant chemotherapy (aOR = 2.14; 95 % CI, 1.29–3.55; p = 0.003), those with postoperative cellulitis (aOR = 3.94; 95 % CI, 2.20–7.06; p < 0.001), and women who developed arm lymphedema (aOR = 2.94; 95 % CI, 1.50–5.77; p = 0.002) had significantly higher odds of developing BL. ConclusionPatients with larger breast volumes, Black patients, those receiving chemotherapy, and those who develop arm lymphedema or cellulitis may be at higher risk of BL after lumpectomy and RT, suggesting that patients with these risk features may benefit from complementary or alternative surgical approaches and heightened monitoring to avoid BL.

Preoperative Ultrasound-Guided Marking, Mammogram, and Peroperative Use of Image Intensifier: A Cost-Effective Technique in Clipped Non-Palpable Breast Cancer Lesions to Achieve Adequate Surgical Margins.

To measure the effectiveness of localisation and removal of impalpable target lesions without compromising patient safety in a resource-limited setup using preoperative ultrasound and mammography with peroperative use of C-arm image intensifier. Descriptive study. Place and Duration of the Study: Department of Breast Surgery, Ittefaq Hospital (Trust), Lahore, Pakistan, from 25th October 2011 to 17th February 2023. All the breast cancer patients who achieved complete clinical response after neoadjuvant systemic treatment and underwent breast conservation surgery during the study period were included. Tumour / clip localisation was done using preoperative ultrasound or image-guided marking, a 2-view mammogram in all cases and the use of an image intensifier to confirm the presence of clips in the excised specimen. The primary outcome was the accurate localisation and removal of the index lesion, while the secondary outcome included the reoperation rate for positive margins and early local recurrence. Data from 144 patients were reviewed. Successful localisation was done in all the patients; only one patient had a positive margin for ductal carcinoma-in situ (DCIS), achieving a 99.3% clear margin rate. Local recurrence within two years after primary operation was seen in one patient only. Conclusion: By a combined approach of preoperative ultrasound-guided marking, a 2-view mammogram, and the use of image intensifier, successful localisation of an impalpable breast lesion is possible without compromising oncological and aesthetic principles. Breast conservation surgery, Localisation, Non-palpable, Margins, Image intensifier.

Preoperative Ultrasound-Guided Marking, Mammogram, and Peroperative Use of Image Intensifier: A Cost-Effective Technique in Clipped Non-Palpable Breast Cancer Lesions to Achieve Adequate Surgical Margins.

To measure the effectiveness of localisation and removal of impalpable target lesions without compromising patient safety in a resource-limited setup using preoperative ultrasound and mammography with peroperative use of C-arm image intensifier. Descriptive study. Place and Duration of the Study: Department of Breast Surgery, Ittefaq Hospital (Trust), Lahore, Pakistan, from 25th October 2011 to 17th February 2023. All the breast cancer patients who achieved complete clinical response after neoadjuvant systemic treatment and underwent breast conservation surgery during the study period were included. Tumour / clip localisation was done using preoperative ultrasound or image-guided marking, a 2-view mammogram in all cases and the use of an image intensifier to confirm the presence of clips in the excised specimen. The primary outcome was the accurate localisation and removal of the index lesion, while the secondary outcome included the reoperation rate for positive margins and early local recurrence. Data from 144 patients were reviewed. Successful localisation was done in all the patients; only one patient had a positive margin for ductal carcinoma-in situ (DCIS), achieving a 99.3% clear margin rate. Local recurrence within two years after primary operation was seen in one patient only. Conclusion: By a combined approach of preoperative ultrasound-guided marking, a 2-view mammogram, and the use of image intensifier, successful localisation of an impalpable breast lesion is possible without compromising oncological and aesthetic principles. Breast conservation surgery, Localisation, Non-palpable, Margins, Image intensifier.

Real-World Implications of the SOUND Trial.

The SOUND trial demonstrated that omission of sentinel lymph node biopsy (SLNB) is noninferior to axillary staging in patients with early-stage breast cancer (BC) and negative axillary ultrasound (AxUS). We examined the generalizability of these findings in patients with hormone receptor (HR)+HER2- disease. Patients with cT1N0M0, HR+HER2- BC and negative AxUS undergoing breast conservation with SLNB from 2016 to 2023 were identified from a prospectively maintained database. Clinicopathologic characteristics, disease burden, adjuvant treatment, and oncologic outcomes were examined and compared with the SLNB arm of the SOUND trial. In postmenopausal patients, the impact of nodal status and 21-gene recurrence score on chemotherapy recommendations were also examined. Of 3972 patients with cT1N0M0 HR+HER2- breast cancer, 544 underwent AxUS; 312 met SOUND eligibility criteria. Median age was 57 (interquartile range [IQR] 48-64) years, and 199 (63.8%) were postmenopausal. Median (IQR) tumor size was 1.3 (0.9-1.7) cm, and 260 (83.3%) tumors were grade 1 or 2. Sentinel lymph node biopsy was positive in 38 (12.2%) patients. Only three (0.4%) had ≥ 4 positive lymph nodes. At a median follow-up of 26.2 (IQR 10.8-38.2) months, there were no axillary recurrences and one (0.3%) distant recurrence. Among postmenopausal women with recurrence score ≤ 25, chemotherapy recommendations were not associated with nodal status. Examination of our real-world HR+ HER2- "SOUND-eligible" population suggests that nodal disease burden and oncologic outcomes are similar to the SOUND trial population, supporting careful implementation of trial results into multidisciplinary practice. In postmenopausal patients, omission of SLNB does not appear to impact adjuvant chemotherapy recommendations.

Evaluating the Effect of MarginProbe® Use on Re-excisions After Partial Mastectomy: A Single-Institution Analysis.

Breast conservation therapy is a widely accepted approach in treating breast cancer, yet the average re-excision rates are approximately 25% despite surgical advancements. The Food and Drug Administration (FDA)-approved MarginProbe® device uses radiofrequency spectroscopy for intraoperative margin assessment, potentially reducing re-excision rates. This study evaluated the effectiveness of MarginProbe® in reducing re-excisions compared with standard of care (SOC). A prospective cohort with MarginProbe® usage during partial mastectomies from June 2019 to July 2023 (153 patients) was compared with a retrospective control group without the device from January 2015 to May 2019 (300 patients). Both groups underwent partial mastectomies performed by two breast surgeons. Positive margins were defined as tumor on ink for invasive cancers and within 2 mm for ductal carcinoma in situ. When control was used for patient demographics and tumor characteristics, the findings showed that MarginProbe® significantly decreased the probability of re-excision by 58% (p<0.001), although it led to a higher shave volume, with an average of 9.8cc additional tissue removed compared with SOC (p < 0.001). Human epidermal growth factor 2 (HER2) positivity was significantly associated with increased odds of re-excision (p = 0.036). MarginProbe® demonstrated a sensitivity of 70.1% and a specificity of 47.5%. MarginProbe® is an effective adjunct for intraoperative margin assessment to decrease re-excision rates. However, patient selection is paramount. Given its significant increase in shave volume, women with small breasts may be at higher risk for poor cosmesis. Surgeons should exercise clinical judgement when determining the suitability of MarginProbe® use for patients undergoing breast conservation. Further research is necessary to refine MarginProbe®'s specificity and to optimize its clinical application.

Long-term clinical outcomes of male breast cancer patients treated with curative intent by trimodality therapy at an academic university hospital in India.

Male breast cancer is rare and accounts for less than 1% of all breast cancer cases worldwide. This retrospective cohort study included all patients of invasive male breast cancer treated with curative intent by a trimodality approach via a multidisciplinary team at an academic university hospital in India between 2009 and 2023. Records were identified from a prospectively maintained database. Clinicopathological parameters, treatment details and survival were recorded and analysed. Thirty-four patients were included. The median (IQR) age was 55(44-63) years. Most patients were overall stage III (74%) and node positive (79%) with Scarff-Bloom-Richardson grade II (50%). Twenty-five patients (73%) were oestrogen receptor (ER) positive. Lymphovascular space invasion (LVSI) and perineural invasion (PNI) were present in 62% and 21% of patients, respectively. The most common chemotherapy timing was adjuvant (53%) followed by neoadjuvant (41%), and the most commonly used regimen consisted of a combination of doxorubicin-cyclophosphamide followed by a taxane (53%). Most (85%) patients underwent a mastectomy, five patients underwent breast conservation. All patients received radiotherapy to a dose of 42.6 Gy in 16 fractions, followed by a tumour bed boost for those undergoing breast conservation. At a median follow-up of 70 months (range 10-159 months), the five and ten-year overall survival was 91% and 58%, and the five-year disease-free survival (DFS) was 67%. The median DFS was 72 months. On univariate analysis, the tumour sub-type (Luminal versus TNBC) significantly predicted DFS (P = 0.03 log-rank). Breast cancer in males has a high incidence of node positivity, ER positivity and LVSI. Even with advanced stages at presentation, trimodality therapy in a multidisciplinary setting offers good long-term outcomes.

583 Use of LICAP Flap Reconstruction in a Breast Cancer Patient with Cosmetic Implants Undergoing Breast Conserving Surgery

583 Use of LICAP Flap Reconstruction in a Breast Cancer Patient with Cosmetic Implants Undergoing Breast Conserving Surgery

Clinical Outcomes for BRCA Pathogenic Variant Carriers With Breast Cancer Undergoing Breast Conservation

Although most women with BRCA-associated breast cancer choose bilateral mastectomy, current guidelines support breast-conserving therapy as an option. As the indications for genetic testing expand and targeted therapies emerge, understanding the outcomes of breast-conserving therapy in the population of patients choosing breast conservation is important. To describe the clinical outcomes of women with BRCA-associated breast cancer who were treated with breast-conserving therapy, including the risks of ipsilateral and contralateral cancer events and bilateral mastectomy-free survival. This cohort study conducted at a single-institution academic national comprehensive cancer center included 172 women identified from a prospectively maintained database who had pathogenic BRCA1/2 variants and were treated with breast-conserving therapy from January 1, 1977, to December 31, 2021. Clinical and pathologic characteristics for patients with BRCA1 and BRCA2 were compared, and estimates of overall survival, bilateral mastectomy-free survival, distant disease-free survival, risk of ipsilateral breast cancer, and risk of contralateral cancer were computed. The cohort included 172 women (mean [SD] age, 47.1 [11.7] years), with 42 (24.4%) receiving a diagnosis of breast cancer prior to 40 years of age. Compared with BRCA2 variant carriers (80 [46.5%]), women with BRCA1 variants (92 [53.5%]) were younger at breast cancer diagnosis and tended to have more advanced tumors, which were more likely to be hormone receptor negative and higher grade. At a median follow-up of 11.8 years (IQR, 5.7-18.2 years), estimates of 10-year survival and risk were: overall survival, 88.5% (95% CI, 83.1%-94.2%); bilateral mastectomy-free survival, 70.7% (95% CI, 63.3%-78.9%); risk of an ipsilateral breast cancer event, 12.2% (95% CI, 5.8%-18.2%); and risk of contralateral cancer, 21.3% (95% CI, 13.3%-28.6%). Risks continued to increase after 10 years of follow-up. In this cohort study, although women with breast cancer and pathogenic BRCA1/2 variants treated with breast-conserving therapy had above-average risks of ipsilateral and contralateral breast cancer events, most did not have another cancer event and remained bilateral mastectomy free. These findings may be useful for informing patients with BRCA variants choosing breast conservation.

Neoadjuvant pertuzumab, docetaxel, carboplatin, and trastuzumab (PTCH) regimen in patients with HER2 positive early, locally advanced, and oligometastatic breast cancer: Real-world Indian experience.

e12556 Background: Pertuzumab/docetaxel/carboplatin/trastuzumab (PTCH) regimen constitutes one of the standard neoadjuvant treatments in human epidermal growth factor receptor-2 (HER2) positive breast cancer. The real-world outcomes of its use from the Indian sub-continent are lacking. Methods: We retrospectively reviewed the medical records of 114 HER2-positive BC patients presenting with nonmetastatic or oligometastatic disease and treated with a uniform PTCH regimen in a neoadjuvant setting at the All India Institute of Medical Sciences, New Delhi, India, between Jan 2015 to May 2023. Total six cycles of PTCH [pertuzumab (840 mg loading followed by 420 mg), docetaxel (75 mg/m2), carboplatin (AUC 6), trastuzumab (8 mg/kg loading followed by 6 mg/kg) q21 days] were administered with primary GCSF prophylaxis. The primary outcome was invasive disease-free survival (iDFS). The secondary outcomes included pathological complete response (pCR) rates, overall survival (OS), and toxicity. Adjuvant trastuzumab is used for patients achieving pCR, while for patients not achieving pCR option of adjuvant trastuzumab emtansine (T-DM1) or trastuzumab was decided based on patient affordability. Results: One hundred and fourteen (114) patients were included with a median age of 47 years (range, 23-70). Overall, 52 (45.6%) patients had hormone-positive disease and 73 (64.01%) were premenopausal. Forty patients (35.08%) had stage II, 62 (54.38%) had stage III, and 12(10.5%) had oligometastatic disease. Sixty-one (53.5%) patients underwent breast conservation surgery and pCR was observed in 62 (54.38%) cases. With a median follow-up of 31 months, the 3-year iDFS was 81.5% and overall OS was not reached. Median iDFS was 33 months in patients with node-positive disease and was not reached in patients with node-negative disease. Three-year iDFS was 68.1% in patients who achieved pCR and 49.8% in those who did not achieve pCR (p=0.001). Grade 3/4 toxicity was seen in 26.7% of patients which caused dose modification and interruption in 13.9% of patients. The most common grade 3/4 toxicity was diarrhea in16 (14.03%) cases and thrombocytopenia in 11 (9.6)% cases . Febrile neutropenia was seen in 4 (3.5%) patients. Four patients (3.5%) had a reversible decrease in cardiac left ventricular ejection fraction. Conclusions: In a real-world context, PTCH is an effective and safe anthracycline-free regimen for use in curative (adjuvant and neoadjuvant) setting for HER2 positive breast cancer in Indian women Using neoadjuvant PTCH may improve pCR and obviate the need for adjuvant T-DM1 after surgery making it a cost-effective strategy in limited recourse setting. The survival outcomes were significantly better among those with node-negative disease and among those who achieved a pCR.

An overview of psychological analysis of patients with breast cancer undergoing total mastectomy and breast conservation surgery and its impact on objectified body consciousness at a tertiary care cancer centre.

e12537 Background: Breast cancer is the most common cancer among females, and surgery plays a central role in its treatment. Surgical treatments may have a negative psychological impact on women’s mental health regarding their body image. The purpose of this study was to compare the psychological health insights pertaining to objectified body consciousness scores before and after the surgery and also to observe whether these scores were comparable across the surgery types. Methods: This retrospective qualitative study included 706 breast carcinoma patients who underwent either Breast Conservation Surgery or Total Mastectomy at Manipal Cancer Centre, between the years 2020-2021. A validated questionnaire of Objectified Body Consciousness was used to obtain responses at diagnosis and at 6 months postsurgery and final scores were calculated for both instances. Two sample t- tests/analysis of variance and Chi-square tests were used to compare continuous and categorical variables respectively. Results: Out of total 706 breast cancer patients, 402 patients underwent Breast Conservation Surgery and 304 underwent Total Mastectomy procedure. A statistically significant change was seen in the mean Objectified Body Consciousness Score (14.22±15.44) for all patients when compared pre-operatively (72.72±11.38) and postoperatively (60.15±17.58). This change was higher in the Total Mastectomy group (29.38±11.53). Also, statistically significant rise in scores was seen with increasing age. There was a statistically significant difference between BCS and Total Mastectomy groups with respect to the distribution of age group, marital status, types of cancer, stage and grade of cancer, NACT administration and postoperative mean objectified body consciousness scores of patients (p-value &lt;0.05). Conclusions: We could affirmatively conclude in our study that younger breast cancer patients and all patients who underwent a total mastectomy, had more psychological apprehension with the body image post-surgery, signifying these groups should be encouraged by healthcare professionals to reach out for counselling at the earliest. Knowing the pre-operative Objectified Body Consciousness scores and the type of surgery the patient is going to undergo, will help us to streamline categorical psycho-educational programs for each group and personalise our healthcare professionals to encourage women to reach out to social support groups and directed counselling at the earliest. This will help women adapt to their transformed life and be mentally prepared for the changes that are expected post-surgery.

Breast conservation versus mastectomy for metaplastic breast cancer: A systematic review and meta-analysis.

Metaplastic breast cancer is a rare aggressive subtype of breast cancer for which there are no clear treatment guidelines regarding the optimal surgical approach. This systematic review and meta-analysis aimed to evaluate survival outcomes of patients with metaplastic breast cancer undergoing breast conservation compared with mastectomy. We identified studies from MEDLINE, Pubmed, EMBASE, Google Scholar, the Cochrane Library Register of Controlled Trials and the EBM Reviews Register. Studies were deemed suitable for inclusion where they compared breast-conserving surgery to mastectomy with the primary outcome of overall survival. Survival data were pooled using a random-effects model. From the 456 citations screened by our search, three studies were assessed as eligible for inclusion. There were a total of 2995 patients who underwent mastectomy and 1909 who underwent breast conservation. The median follow-up time was 43 months. Meta-analysis demonstrated no significant difference between breast conservation and mastectomy (pooled HR 0.89, 95% CI, 0.56-1.42, p=0.631). Wide local excision, in conjunction with adjuvant radiation and judicious use of chemotherapy, may be a reasonable alternative to mastectomy as surgical management of metaplastic breast cancer as part of an individualized, multidisciplinary approach.

A Prospective Study of the Efficacy of Endofascial Axillary Dissection to Reduce Axillary Seroma Formation.

Introduction Seroma formation is a common complication following axillary dissection. The pathogenesis of seroma is poorly understood. Various chemical and mechanical methods have been tried to reduce seroma with varying results. In this study, we look at a novel method of axillary dissection to reduce seroma and its attendant morbidity. The objective of the study is to compare endofascial axillary lymphadenectomy with routine axillary lymphadenectomy regarding axillary drain output following breast conservation surgery. Methods We did a prospective interventional study of endofascial axillary dissection in patients undergoing breast conservation surgery. Comparison was done with historical controls who underwent breast conservation surgery with routine axillary lymphadenectomy before the study period. All patients were operated by the same surgeon. Results Breast conservation surgery with endofascial axillary dissection was performed in 36 patients and compared with 36 patients who underwent routine axillary dissection before the study period. The mean total axillary drain output in the endofascial and routine groups were 796.8 and 1,259.3 mL, respectively ( p = 0.001). The average day of drain removal in the endofascial and routine groups were 10.8 and 14.9 days, respectively ( p = 0.001). The nodal yield of the endofascial and routine groups were 15.3 and 16.4 nodes, respectively ( p = 0.449). The duration of surgery of the endofascial and routine groups were 89.3 and 85.1 minutes, respectively ( p = 0.366). Conclusion Endofascial axillary dissection significantly reduced the mean total axillary drain output and resulted in early drain removal compared with routine axillary dissection. There were no significant differences in the nodal yield, operative time, seroma aspirations, and wound complications between the endofascial and routine axillary dissection groups.

Abstract PO2-07-04: Applying the Alliance Trial Guidelines in Multi-focal Breast Disease Using an Artificial Intelligence Computational Platform: Economic Analysis and Cosmetic Sensitivity

Abstract Background: Traditionally, multi-focal breast cancer results in mastectomy. The Alliance Trial offers a paradigm shift in surgical options available for multi-focal breast cancer patients in the context of adjuvant chemotherapy. In the trial, patients with multi-focal disease (&amp;lt; 3 tumors) who underwent breast conservation surgery (BCS) were found to have similar outcomes to patients undergoing mastectomy. BCS for large volume tumors ( &amp;gt;30%) has been cited as having a high potential for cosmetic defect, and hence represents a typical upper limit for potential tissue removal in BCS. Here, we evaluated a patient cohort to better understand the economic impact of the Alliance trial and further categorize patients that would most benefit without suffering cosmetic impact. We employed a novel computational technology to quantify the ratio of tumor size to breast tissue volume. Methods: Using a publicly available, single site cohort (n=243, DUMC) of breast cancer patients that underwent mastectomy, we segmented the tumors using our TumorSight Viz software platform. This platform uses artificial intelligence to segment the tumor and surrounding tissues and allows for a volumetric and morphologic assessment in 3D space. We then applied relevant inclusion/exclusion criteria from the Alliance Trial to the cohort (Saha et al, 2018). In trial eligible patients, we used TumorSight Viz to create a convex hull (CH) around the multi-focal disease using dilations of 1 cm and 2 cm. The volume of the CH, corresponding to proposed surgical extirpation, and the overall breast volume (BV) were then computationally assessed in 3D. The ratio of CH to BV (CH:BV) was calculated and a cutoff of 30% (high potential for cosmetic deformity) was applied. A cost analysis was then carried out. We determined the aggregate per annum savings that could potentially be realized by transforming a subset of mastectomies to BCS by tabulating total costs of mastectomy+reconstruction vs. BCS+WBI (whole-breast irradiation), as well as adjusted for relative rates of adjuvant therapy (~80%) across the nationwide patient population. Results: We found that 19.3% of adjuvant mastectomy patients were eligible for BCS based on Alliance Trial criteria. Of those, 68% had tumor CH:BV &amp;lt; 30% when using a 1 cm dilation around the tumor. When using a 2 cm dilation, 56% had tumor CH:BV &amp;lt; 30%. Together, these results indicate that of all adjuvant mastectomy patients, an estimated 10.8-13.1% are eligible for BCS based on volumetric measures of cosmetically acceptable breast tissue removal. Our economic analysis of BCS vs. mastectomy revealed an estimated $28,500 cost savings for patients with private insurance, suggesting that both decreased costs and improved quality-of-life (QOL) can be mutually aligned. By assessing the nationwide number of patients receiving adjuvant therapy for breast cancer, alongside the percentage potentially eligible for BCS using the above cosmetic defect analysis, we estimate that BCS conversion from mastectomy offers to provide a net savings of $300-350 million annually. Conclusion: The Alliance Trial guidelines unveiled the potential option of BCS in ~20% of patients with multi-focal disease in our cohort, demonstrating considerable cost-savings. Computational tools can further differentiate individuals who may not be best candidates for BCS in this setting, ensuring high QOL and informed decision-making. Citation Format: John Pfeiffer, Matthew Biancalana, Dorys Lopez-Ramos, Bradley Feiger, Anuja Antony. Applying the Alliance Trial Guidelines in Multi-focal Breast Disease Using an Artificial Intelligence Computational Platform: Economic Analysis and Cosmetic Sensitivity [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 PO2-07-04.

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.

Abstract PO5-23-05: The Impact of Bi-Annual Diagnostic Imaging on Detecting Ipsilateral Breast Recurrence in Patients Undergoing Breast Conserving Surgery for Breast Cancer

Abstract Introduction: Breast conserving surgery (BCS) represents the preferred option for surgical treatment for a majority of patients with early-stage breast cancer who are eligible for this approach. When compared with mastectomy approaches, BCS provides patients with equivalent survival while preserving the affected breast. It is necessary to achieve clear surgical margins as positive lumpectomy margins are associated with an increased risk for ipsilateral breast tumor recurrence. With advances in imaging techniques, as well as effective systemic therapy and contemporary radiation therapy, local recurrence after BCS has decreased and overall survival for patients has improved. Retrospective studies have quantified the recurrence rate in unifocal breast cancer as 8 - 15% at 20 years. The NCCN recommends annual mammography at least 6 months after post-lumpectomy radiation therapy, but there is little data regarding more frequent surveillance after lumpectomy in the early post-operative setting. The purpose of this study was to evaluate the impact of short interval surveillance mammography on the detection of early in-breast recurrence in patients undergoing BCS. Methods: Our IRB-approved Breast Cancer Database was queried for patients enrolled from 11/2009 to 6/2023 who underwent breast conservation surgery for a diagnosis of in situ or invasive breast cancer in this retrospective analysis. Per our institutional protocol, patients were recommended to undergo diagnostic mammography of the treated breast(s) every 6 months for 2 years after BCS. After the initial 2 year period, bilateral mammography was performed annually in the absence of other indications. Additional supplemental imaging such as breast ultrasound and MRI were performed at physician discretion and based on patient risk and breast density. Variables of interest included the presence of pathogenic germline mutations, family history of breast cancer, and disease characteristics. Our primary endpoint was ipsilateral breast tumor recurrence. Results: Of 2491 patients who underwent breast conservation surgery for in situ or invasive breast cancer, 191 (7.7%) developed recurrent disease, including ipsilateral and contralateral recurrence, and distant disease, in the study period. A total of 83 (3.2%) patients developed ipsilateral breast recurrence during the entire study period. Of those, 19 (22.9%) were detected within the first two years after surgery. Six of the 19 patients (31.6%) had their recurrences detected on yearly diagnostic mammography while 6 (31.6%) patients had their recurrences detected on interval 6-month unilateral diagnostic imaging. In both groups, 5/6 recurrences were invasive disease after an original diagnosis of invasive cancer, and the remaining patient had recurrent DCIS. The remaining 7/19 patients (36.8%) had their ipsilateral recurrences detected on palpation or other diagnostic imaging. In this group as well, there was one case of recurrent DCIS, with the remaining 6 cases representing recurrent invasive cancer. Of the 19 patients with ipsilateral recurrences, none had pathogenic germline mutations. 4 of the 19 patients (21%) had positive margins after their initial lumpectomy surgery with re- excisions required to achieve clear margins. Conclusion: Interval diagnostic surveillance imaging every 6 months after breast conserving surgery identified almost one-third of the ipsilateral breast tumor recurrences that occurred within the first 2 years after surgery in our population. While our numbers are small, the relationship of re-excision lumpectomy surgery to subsequent risk for local recurrence has been described by others, and bears further study. Particularly in view of our observation that the majority of in-breast recurrences were invasive, our data supports the practice of more frequent imaging follow up in the first 2 years after breast conserving surgery. Citation Format: Pabel Miah, Laura Fiedler, Anthony Baez, Athanasios Sevdalis, Alyssa Marmer, Charles DiMaggio, Linda Pak, Richard Shapiro, Karen Hiotis, Deborah Axelrod, Amber Guth, Freya Schnabel. The Impact of Bi-Annual Diagnostic Imaging on Detecting Ipsilateral Breast Recurrence in Patients Undergoing Breast Conserving Surgery for 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 PO5-23-05.

Nipple-Sparing Mastectomy and Adequate Margins for Patients With Ductal Carcinoma In Situ.

For patients with ductal carcinoma in situ (DCIS) undergoing breast conservation surgery (BCS), guidelines advise a margin width of at least 2mm, with studies demonstrating decreased recurrence risk compared to narrower margins. However, limited data exist establishing if this margin is appropriate in mastectomies, and specifically for nipple-sparing mastectomy (NSM). Consequently, we evaluated the margins of DCIS patients undergoing NSM and resulting oncologic outcomes. A single-institution retrospective review was performed in patients with DCIS or DCIS with microinvasion (DCIS + MI) undergoing NSM from April 2010 to December 2021. Patient and tumor characteristics, margin status, treatment, and outcomes information were collected. The association between margins and local-regional (LRR) and distant recurrence (DR) were examined. 161 patients were included, comprising 284 NSM (164 therapeutic, 120 prophylactic). 153 patients had DCIS and 8 had DCIS + MI. Most patients had hormone sensitive, 123 (76.4%), and nuclear grade 2, 72 (44.7%), disease. In total, 35 (21.7%) patients had positive or <2mm margins. Of these, 21 (60%) involved the anterior margin. At a median follow-up of 45 months (range 0-151), 2.5% (n = 4) had a LRR and .6% (n = 1) had a DR. Of patients with a recurrence, only 2 had positive or <2mm margins, 1 had received endocrine therapy, and none received adjuvant radiation. No specific margin status was found to correlate with recurrence for patients with DCIS or DCIS + MI undergoing NSM, with an altogether low recurrence risk. Overall, this suggests that recommended DCIS margins in BCS doesn't necessarily apply in NSM, where margins of <2mm may be acceptable.

Surveillance Imaging in Breast Cancer Patients Undergoing Breast Conserving Surgery With Chest Wall Perforator Flap Reconstruction

Surveillance Imaging in Breast Cancer Patients Undergoing Breast Conserving Surgery With Chest Wall Perforator Flap Reconstruction

Chest wall perforator flap partial breast reconstruction: a retrospective analysis of surgical, cosmetic and survival outcome.

Oncoplastic breast surgery includes volume replacement as well as volume displacement. Autologous tissue is the preferred approach for volume replacement and includes chest wall perforator flaps (CWPF). Although described more than a decade ago, CWPFs have not been adopted widely in clinical practice till recently. We report the largest single-centre institutional data on CWPFs. The study includes all patients who underwent breast conservation surgery (BCS) using CWPFs from January 2015 to December 2022. Data were retrieved from the institutional electronic record and Redcap database. The analysis was done using SPSS 23 and STATA 14. 150 patients were included in the study. The mean age was 48.8 years (SD 10.4), and the body mass index was (26.6 kg/m2, SD 4.3). >50% of patients had breasts with small cup sizes (A&B) and mild ptosis (Non-ptotic and Grade 1 ptosis). 44.7% of patients underwent lateral intercostal artery perforator flap (LICAP), anterior intercostal artery perforator flap in 31.3%, lateral thoracic perforator flap (LTAP) in 12%, LICAP + LTAP in 11.3% and thoracodorsal artery perforator flap in 1%. Post-operatively, haematoma was seen in 1.3%, complete flap necrosis in 1.3%, seroma in 7%, wound dehiscence in 12%, and positive margin in 6.7%. 92 patients responded to the satisfaction assessment, of which >90% were happy with the surgical scars, comfortable going out in a public place, satisfied with the symmetry of the breast, and no one chose mastectomy in hindsight. The 5-year predicted disease free survival and overall survival were 86.4% and 94.7%, respectively. BCS with CWPF is an excellent option for reconstruction in small to medium-sized breasts. It is associated with minimal morbidity and comparable patient-reported cosmetic and survival outcomes.

202 (PB-109) Poster - Omission of axillary clearance in early breast cancer with positive sentinel node undergoing breast conservation: preliminary results of Z0011 criteria application in clinical practice

202 (PB-109) Poster - Omission of axillary clearance in early breast cancer with positive sentinel node undergoing breast conservation: preliminary results of Z0011 criteria application in clinical practice