Impact of margin assessment method on positive margin rate and total volume excised

Pathology and resection margins following mastectomy prior to immediate breast reconstruction

Risk of local recurrence (LR) (and even distant disease-free survival) after mastectomy is associated with margin status. Furthermore, the vast majority of LR are located at the anterior (superficial) margin. Margins in mastectomy are considered anatomical borders and not true resection margins; such a conception may erroneously lead to underestimation of the risk of LR after mastectomy. If dissection is accurate along the fascia, only skin, subcutaneous tissue and minimal residual breast gland tissue (rBGT) are expected to remain in the patient. However, the subcutaneous fascia is an inconsistent anatomical structure that may be absent in almost half of patients. Studies and routine clinical practice suggest that resection may frequently, though often focally, be within the breast glandular tissue leaving various amounts of rBGT. Such areas may be nidus for subsequent de novo or recurrent premalignant or malignant disease. There is no consensus on handling of close/positive margins and intervention is extrapolated from studies on breast conserving surgery with subsequent radiotherapy. Handling of a close/positive margin is complicated by poor correlation between the ex vivo findings on the specimen and the attempt to relocate the area of concern in a patient with reconstructed breasts. In this clinical practice review, we strongly advocate for reporting of the lesion-to-margin distance in mastectomies to collect further evidence on the association between LR and margin status.

Oncoplastic breast surgery to prevent "Bird's beak" deformity in the breast: a comparative retrospective study

PURPOSES

Breast deformity occurring in the lower pole after breast conserving surgery (BCS) is known as bird's beak (BB) deformity. This retrospective study evaluated the outcomes in breasts reconstructed with a conventional closing procedure (CCP) and a downward-moving procedure (DMP), respectively, after BCS.

METHODS

In CCP, the inferomedial and inferolateral portions of breast tissues were reapproximated toward the midline after wide excision to repair the breast defect. In DMP, the retro-areolar breast tissue was detached from the nipple-areolar complex after wide excision, and the upper pole breast tissue was moved downward to refill the breast defect.

RESULTS

CCP was performed in 20 patients (Group A), and DMP was performed in 28 patients (Group B). Although retraction of the lower part of the breast was postoperatively observed in 13 (72%) of 18 patients from Group A, it was observed in 7 (28%) of 25 patients in Group B (p < 0.05). The downward pointing of the nipple was observed in 8 (44%) of 18 patients from Group A and in 4 (16%) of 25 patients in Group B (p < 0.05).

CONCLUSIONS

DMP is more useful for preventing BB deformity than CCP.

Does Non-Classic Lobular Carcinoma In Situ at the Lumpectomy Margin Increase Local Recurrence?

BACKGROUND

The clinical significance of nonclassic, lobular carcinoma in situ (NC-LCIS) at the surgical margin of excisions for invasive cancer is unknown. We sought to determine whether NC-LCIS at or near the margin in the setting of a concurrent invasive carcinoma is associated with risk of ipsilateral breast tumor recurrence (IBTR) and locoregional recurrence (LRR).

METHODS

Patients with stage 0-III breast cancer and NC-LCIS who underwent lumpectomy between January 2010 and January 2022 at a single institution were retrospectively identified. NC-LCIS margins were stratified as <2 mm, ≥2 mm, or within shave margin. Rates of IBTR and LRR were examined.

RESULTS

A total of 511 female patients (median age 60 years [interquartile range (IQR) 52-69]) with NC-LCIS and an associated ipsilateral breast cancer with a median follow-up of 3.4 years (IQR 2.0-5.9) were identified. Final margins for NC-LCIS were ≥2 mm in 348 patients (68%), <2 mm in 37 (7.2%), and within shave margin in 126 (24.6%). Crude incidence of IBTR was 3.3% (n = 17) and that of LRR was 4.9% (n = 25). There was no difference in the crude rate of IBTR by NC-LCIS margin status (IBTR rate: 3.7% ≥2 mm, 0% <2 mm, 3.2% within shave margin, p = 0.8) nor in LRR (LRR rate: 4.9% ≥2 mm, 2.7% <2 mm, 5.6% within shave margin, p = 0.9).

CONCLUSIONS

For completely excised invasive breast cancers associated with NC-LCIS, extent of margin width for NC-LCIS was not associated with a difference in IBTR or LRR. These data suggest that the decision to perform reexcision of margin after lumpectomy should be driven by the invasive cancer, rather than the NC-LCIS margin.

Development of intraoperative assessment of margins in breast conserving surgery: a narrative review

OBJECTIVE

We intend to provide an informative and up-to-date summary on the topic of intraoperative assessment of margins in breast conserving surgery (BCS). Conventional methods as well as cutting-edge technologies are analyzed for their advantages and limitations in the hope that clinicians can turn to this for reference. This review can also offer guidance for technicians in the future design of intraoperative margin assessment tools.

BACKGROUND

Achieving negative margins during BCS is one of the vital factors for preventing local recurrence. Conducting intraoperative margin assessment can ensure negative margins to a large extent and possibly relieve patients of the anguish of re-interventions. In recent years, innovative methods for margin assessment during BCS are advancing rapidly. And there is a lack of summary regarding the development of intraoperative margin assessment in BCS.

METHODS

A PubMed search with keywords "intraoperative margin assessment" and "breast conserving surgery" was conducted. Relevant publications were screened manually for its title, abstract and even full text to determine its true relevance. Publications on neo-adjuvant therapy and intraoperative radiotherapy were excluded. References from the searched articles and other supplementary articles were also looked into.

CONCLUSIONS

Conventional methods for margin assessment yields stable outcome but its use is limited because of the demand on pathology staff and the trade-off between time and precision. Conventional imaging techniques pass the workload to radiologists at the cost of a significantly low duration of time. Involving artificial intelligence for image-based assessment is a further improvement. However, conventional imaging is inherently flawed in that occult lesions can't show on the image and the showing ones are ambiguous and open to interpretation. Unconventional techniques which base their judgment on cellular composition are more reassuring. Nonetheless, unconventional techniques should be subjected to clinical trials before putting into practice. And studies regarding comparison between conventional methods and unconventional methods are also needed to evaluate their relative efficacy.

Multi-magnification-based machine learning as an ancillary tool for the pathologic assessment of shaved margins for breast carcinoma lumpectomy specimens

The surgical margin status of breast lumpectomy specimens for invasive carcinoma and ductal carcinoma in situ (DCIS) guides clinical decisions, as positive margins are associated with higher rates of local recurrence. The "cavity shave" method of margin assessment has the benefits of allowing the surgeon to orient shaved margins intraoperatively and the pathologist to assess one inked margin per specimen. We studied whether a deep convolutional neural network, a deep multi-magnification network (DMMN), could accurately segment carcinoma from benign tissue in whole slide images (WSIs) of shave margin slides, and therefore serve as a potential screening tool to improve the efficiency of microscopic evaluation of these specimens. Applying the pretrained DMMN model, or the initial model, to a validation set of 408 WSIs (348 benign, 60 with carcinoma) achieved an area under the curve (AUC) of 0.941. After additional manual annotations and fine-tuning of the model, the updated model achieved an AUC of 0.968 with sensitivity set at 100% and corresponding specificity of 78%. We applied the initial model and updated model to a testing set of 427 WSIs (374 benign, 53 with carcinoma) which showed AUC values of 0.900 and 0.927, respectively. Using the pixel classification threshold selected from the validation set, the model achieved a sensitivity of 92% and specificity of 78%. The four false-negative classifications resulted from two small foci of DCIS (1 mm, 0.5 mm) and two foci of well-differentiated invasive carcinoma (3 mm, 1.5 mm). This proof-of-principle study demonstrates that a DMMN machine learning model can segment invasive carcinoma and DCIS in surgical margin specimens with high accuracy and has the potential to be used as a screening tool for pathologic assessment of these specimens.

Resection of Cavity Shave Margins in Stage 0-III Breast Cancer Patients Undergoing Breast Conserving Surgery: A Prospective Multicenter Randomized Controlled Trial

OBJECTIVE

Single-center studies have demonstrated that resection of cavity shave margins (CSM) halves the rate of positive margins and re-excision in breast cancer patients undergoing partial mastectomy (PM). We sought to determine if these findings were externally generalizable across practice settings.

METHODS

In this multicenter randomized controlled trial occurring in 9 centers across the United States, stage 0-III breast cancer patients undergoing PM were randomly assigned to either have resection of CSM ("shave" group) or not ("no shave" group). Randomization occurred intraoperatively, after the surgeon had completed their standard PM. Primary outcome measures were positive margin and re-excision rates.

RESULTS

Between July 28, 2016 and April 13, 2018, 400 patients were enrolled in this trial. Four patients (2 in each arm) did not meet inclusion criteria after randomization, leaving 396 patients for analysis: 196 in the "shave" group and 200 to the "no shave" group. Median patient age was 65 years (range; 29-94). Groups were well matched at baseline for demographic and clinicopathologic factors. Prior to randomization, positive margin rates were similar in the "shave" and "no shave" groups (76/196 (38.8%) vs. 72/200 (36.0%), respectively, P = 0.604). After randomization, those in the "shave" group were significantly less likely than those in the "no shave" group to have positive margins (19/196 (9.7%) vs. 72/200 (36.0%), P < 0.001), and to require re-excision or mastectomy for margin clearance (17/196 (8.7%) vs. 47/200 (23.5%), P < 0.001).

CONCLUSION

Resection of CSM significantly reduces positive margin and re-excision rates in patients undergoing PM.

Deep Multi-Magnification Networks for multi-class breast cancer image segmentation

Pathologic analysis of surgical excision specimens for breast carcinoma is important to evaluate the completeness of surgical excision and has implications for future treatment. This analysis is performed manually by pathologists reviewing histologic slides prepared from formalin-fixed tissue. In this paper, we present Deep Multi-Magnification Network trained by partial annotation for automated multi-class tissue segmentation by a set of patches from multiple magnifications in digitized whole slide images. Our proposed architecture with multi-encoder, multi-decoder, and multi-concatenation outperforms other single and multi-magnification-based architectures by achieving the highest mean intersection-over-union, and can be used to facilitate pathologists' assessments of breast cancer.

Differences in Re-excision Rates for Breast-Conserving Surgery Using Intraoperative 2D Versus 3D Tomosynthesis Specimen Radiograph

BACKGROUND

Intraoperative specimen radiographs performed during breast conservation surgery for cancer reduces the need for re-excision for positive margins. We studied 2D versus 3D image-guided cavity margin excision and compared it to final pathology and need for additional surgery.

METHODS

We conducted a retrospective review of 657 breast-conserving operations performed for cancer from 2013 to 2018. Procedures were performed by four surgeons at a single tertiary institution with access intraoperatively to 2D and 3D radiographs. Data collected included demographics, intraoperative margin assessment, final pathology, and re-excision rates.

RESULTS

A total of 466 patients had 2D and 191 had 3D specimen imaging. The 2D group had a lower mean age and a higher body mass index and proportion of minority patients than the 3D group (P < 0.01). In the 3D group, there was a higher percentage of patients with mammographically denser breasts (P < 0.06); 58% of patients in the 3D group had additional imaging-directed cavity margins excised versus 32% of patients in the 2D group (P < 0.01). In the 2D group, 44 patients (9%) had positive final margins versus 8 patients (4%) in the 3D group (P = 0.02). No difference was found on total volume of excision (P = 0.56). The re-excision rate for the 2D group was 11% versus 5% for the 3D group (P = 0.02; adjusted odds ratio = 0.41, 95% confidence interval 0.19-0.86).

CONCLUSIONS

Re-excision rates using both modalities are low. A lower re-excision rate is independently associated with 3D tomosynthesis. This allows surgeons to excise additional margins at the index operation, decreasing reoperations and anxiety/costs for patients.

Comparative analysis of margin status in breast conservation surgery and its correlation with subsequent re-excision findings

Purpose

Breast-conservation surgery (BCS) has become a standard treatment option for invasive breast carcinoma (IBC) and ductal carcinoma in situ (DCIS). The strongest predictor of local recurrence remains the surgical margin status. We evaluated the margin positivity by quantifying the tumor on positive margins and analyzing the histologic factors including type and extent in determining the likelihood of residual disease upon re-excision.

Method

Retrospective analysis of 210 BCS performed at Mount Sinai Medical Center from the period of January 2011 - December 2017 revealed that 58 had IBC, DCIS, or both, with positive margins that were followed by re-excision.

Result

The margins had IBC in 18 (31%), DCIS in 32 (55.2%) and both in 8 (13%) cases. Thirty-eight cases (65.5%) were free of carcinoma on re-excision. Of 40 cases with margins positive for DCIS, 16 (40%) had residual DCIS. Of 26 cases with IBC at the margins, and 5 had residual disease (19%). This difference was statistically significant (p = 0.002). Of 21 cases with extensive DCIS, 12 had residual disease (p = 0.02) as compared to only 4 out of 19 without extensive DCIS. None of the cases with clinging/micro-papillary DCIS had residual disease, while 51% of the other types (solid, cribriform, come-do) had residual disease (p = 0.02). The area of DCIS as measured on the involved margin correlated with the amount of residual disease on re-excision (p = 0.03).

Conclusion

Margins positive for DCIS are more likely to have residual disease on re-excision in comparison to margins positive for only IBC. The type and extent of DCIS appears to influence the likelihood of residual disease.

Relocation of inadequate resection margins in the wound bed during oral cavity oncological surgery: A feasibility study

Background

Specimen‐driven intraoperative assessment of the resection margins provides immediate feedback if an additional excision is needed. However, relocation of an inadequate margin in the wound bed has shown to be difficult. The objective of this study is to assess a reliable method for accurate relocation of inadequate tumor resection margins in the wound bed after intraoperative assessment of the specimen.

Methods

During oral cavity cancer surgery, the surgeon placed numbered tags on both sides of the resection line in a pair‐wise manner. After resection, one tag of each pair remained on the specimen and the other tag in the wound bed. Upon detection of an inadequate margin in the specimen, the tags were used to relocate this margin in the wound bed.

Results

The method was applied during 80 resections for oral cavity cancer. In 31 resections an inadequate margin was detected, and based on the paired tagging an accurate additional resection was achieved.

Conclusion

Paired tagging facilitates a reliable relocation of inadequate margins, enabling an accurate additional resection during the initial surgery.

Re-excision rate after sector resection for breast cancer: A 5-year retrospective cohort study

BACKGROUND

Positive margins after Breast conserving surgery (BCS) for breast cancer can result in local recurrence (LR) requiring further surgery. This can lead to unnecessary patient anxiety, poor prognosis and impose additional economic burden to our health system. The aim of this study is to assess the rate of re-excision for positive margins after BCS using the sector resection technique.

METHODS

This single centre retrospective cohort study included all women who underwent BCS using sector resection between the years of 2012 and 2016. A total of 456 patients underwent sector resection. We evaluated the margin status, re-excision rates and their predictive risk factors.

RESULTS

415 (91%) patients had clear margins. 41 (9%) patients underwent further re-excision for positive or close margin. 75.6% of those patients had DCIS and 51% had invasive carcinoma involving the margins. Patient and tumour characteristics associated with an increased risk of positive margin were women under the age of 50 (p = 0.19), tumours >50 mm (p = 0.001), grade-2 (p = 0.48) and grade-3 (p = 0.63), HER-2 positivity (p = 0.02), sentinel lymph node positivity (p = 0.03), and patients undergoing axillary lymph node dissection (p = 0.01).

CONCLUSION

BCS using the sector resection technique has a low re-excision rate for positive margins. Younger patients and aggressive tumour biology are important predictive risk factors for positive margins.

A survey of current surgical treatment of early stage breast cancer in China

The purpose of this national survey is to explore the patterns of surgical management for early stage breast cancer patients in China. A paper questionnaire survey was sent to the representatives from 520 hospitals who attended an international symposium in Guangzhou, China, 2014. The questionnaire included demographic information, initials and most preferred approaches for breast cancer surgery. The results were presented descriptively. The response rate was 42.5%. Only 7% of hospitals with >50% rate of breast conserving surgery (BCS). Intraoperative frozen sections and additional cavity margins assessment were used at 88% and 30.9% of hospitals, respectively. For invasive carcinoma, 15% of participants defined an adequate margin as no tumor cells on the ink. Sentinel lymph node biopsy (SLNB) was routinely performed in 93.2% of hospitals. Only 16.6% of hospitals would embrace the conclusions of the American College of Surgeons Oncology Group (ACOSOG) Z0011 study and omit axillary lymph node dissection (ALND) for patients who fit the Z0011 criteria. The current patterns for the management of breast cancer patients are still lagging behind. Chinese doctors need to catch up with the updated results of the cutting-edge clinical studies and multiple measures are in need to improve this situation.

Costs and effects of intra-operative fluorescence molecular imaging - A model-based, early assessment

Introduction

Successful breast conserving cancer surgeries come along with tumor free resection margins and account for cosmetic outcome. Positive margins increase the likelihood of tumor recurrence. Intra-operative fluorescence molecular imaging (IFMI) aims to focus surgery on malignant tissue thus substantially lowering the presence of positive margins as compared with standard techniques of breast conservation (ST). A goal of this paper is to assess the incremental number of surgeries and costs of IFMI vs. ST.

Methods

We developed a decision analytical model and applied it for an early evaluation approach. Given uncertainty we considered that IFMI might reduce the proportion of positive margins found by ST from all to none and this proportion is assumed to be reduced to 10% for the base case. Inputs included data from the literature and a range of effect estimates. For the costs of IFMI, respective cost components were added to those of ST.

Results

The base case reduction lowered number of surgeries (mean [95% confidence interval]) by 0.22 [0.15; 0.30] and changed costs (mean [95% confidence interval]) by €-663 [€-1,584; €50]. A tornado diagram identified the Diagnosis Related Group (DRG) costs, the proportion of positive margins of ST, the staff time saving factor and the duration of frozen section analysis (FSA) as important determinants of this cost.

Conclusions

These early results indicate that IFMI may be more effective than ST and through the reduction of positive margins it is possible to save follow-up surgeries–indicating further health risk–and to save costs through this margin reduction and the avoidance of FSA.

Surgical margins in the veterinary cancer patient

In veterinary oncologic specimens, histopathology is the gold standard for determining adequacy of excision. Despite limitations of this technique, the pathologist's interpretation of margin status significantly impacts patient management, including indications for adjuvant therapy. This article aims to summarize peer-reviewed literature as it relates to histologic margin evaluation in veterinary cancer patients. The value of histologic tumour-free margins and technical factors influencing histopathologic margin outcomes are also discussed. We review alternative strategies for determining excisional status, and discuss how an evolving understanding of tumour biology might inform clinical and research perspectives on surgical margins. In doing so, we aim to provide context and a stimulus for future investigations into this important yet incompletely understood topic.

Early Adoption of the SSO-ASTRO Consensus Guidelines on Margins for Breast-Conserving Surgery with Whole-Breast Irradiation in Stage I and II Invasive Breast Cancer: Initial Experience from Memorial Sloan Kettering Cancer Center

BACKGROUND

Reexcision rates in patients undergoing breast-conserving surgery (BCS) for early-stage invasive breast cancer are highly variable. The Society of Surgical Oncology (SSO) and American Society for Radiation Oncology (ASTRO) published consensus guidelines to help standardize practice. We sought to determine reexcision rates before and after guideline adoption at our institution.

METHODS

We identified patients with stage I or II invasive breast cancer initially treated with BCS between June 1, 2013, and October 31, 2014. Margins were defined as positive (tumor on ink), close (≤1 mm), or negative (>1 mm), and were recorded for both invasive cancer and ductal carcinoma-in situ (DCIS) components. Reexcision rates were quantified, characteristics were compared between groups, and multivariable logistic regression was performed.

RESULTS

A total of 1205 patients were identified, 504 before and 701 after the guideline adoption (January 1, 2014). Clinical and pathologic characteristics were similar between time periods. Reexcision rates significantly declined from 21.4 to 15.1 % (p = 0.006) after guideline adoption. A multivariable model identified extensive intraductal component (odds ratio [OR] 2.5, 95 % confidence interval [CI] 1.2-5.2), multifocality (OR 2.0, 95 % CI 1.2-3.6), positive (OR 844.4, 95 % CI 226.3-5562.5) and close (OR 38.3, 95 % CI 21.5-71.8) ductal carcinoma-in situ margin, positive (OR 174.2, 95 % CI 66.2-530.0) and close (OR 6.4, 95 % CI 3.0-13.6) invasive margin, and time period (OR 0.5, 95 % CI 0.3-0.9 for post vs. pre) as independently associated with reexcision.

CONCLUSIONS

Overall reexcision rates declined significantly after guideline adoption. Close invasive margins were associated with higher rates of reexcision than negative invasive margins in both time periods; however, the effect diminished in the postguideline adoption period. Thus, we expect continued decline in reexcision rates as adherence to guidelines becomes more uniform.

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

BACKGROUND

Multiple 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.

METHODS

The 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.

RESULTS

The 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.

CONCLUSIONS

A 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.

The importance of surgical margins in breast cancer

Achieving negative margins with "no tumor on ink" is an appropriate goal in breast conserving therapy (BCT). Wider margins do not decrease recurrence rates, and re-excision in patients with microscopic positive margins is warranted. Several strategies exist to increase rates of negative margins, including techniques to improve tumor localization, intraoperative assessment of margins and oncoplastic techniques. Negative margins should be the goal of BCT, as this will improve both local control and long-term survival.

Reasons for re-excision after lumpectomy for breast cancer: insight from the American Society of Breast Surgeons Mastery(SM) database

BACKGROUND

There is marked variability of re-excision rates after initial lumpectomy for breast cancer. Reasons for re-excision and variability across surgeons have not been well documented. We hypothesized the American Society of Breast Surgeons (ASBrS) Mastery(SM) Program can identify reasons for re-excision.

METHODS

Data from January 1 to 7 November 2013 were evaluated in the ASBrS Mastery(SM) Program to determine re-excision lumpectomy rate (RELR). On 1 June 2013, a tool to track reasons for re-excision was developed. Variation in re-excision rate by surgeon and patient characteristics was performed by Chi square test and Fisher's test for univariate analysis, then logistic regression with backwards elimination method for multivariate analysis.

RESULTS

For 6,725 patients undergoing initial lumpectomy for cancer, 328 surgeons reported 1,451 (21.6 %) patients had one or more re-excisions. The most common reasons for re-excision were ink positive margins in 783 (49.7 %), margin <1 mm (34.3 %), and margin 1-2 mm (7.2 %). By multivariate analysis, re-excision rates were lower in patients aged less than 35 years, with White (non-) Hispanic ethnicity, and, among surgeons in solo practice, more years in practice and higher-volume practice.

CONCLUSION

Half of re-excisions after initial lumpectomy were performed for margins that are positive. Most of the remainder were for negative close (<1-2 mm) margins. This information corroborates surgeon survey data regarding reasons for re-excision and provides proof of concept the Mastery(SM) Program can capture surgical outcome data in real time, providing opportunity and a method for future performance improvement.