Appropriate margin for lumpectomy excision of invasive breast cancer

Structured illumination microscopy for cancer identification in diagnostic breast biopsies

Breast cancer is the second most common cancer diagnosed in women in the US with almost 280,000 new cases anticipated in 2023. Currently, on-site pathology for location guidance is not available during the collection of breast biopsies or during surgical intervention procedures. This shortcoming contributes to repeat biopsy and re-excision procedures, increasing the cost and patient discomfort during the cancer management process. Both procedures could benefit from on-site feedback, but current clinical on-site evaluation techniques are not commonly used on breast tissue because they are destructive and inaccurate. Ex-vivo microscopy is an emerging field aimed at creating histology-analogous images from non- or minimally-processed tissues, and is a promising tool for addressing this pain point in clinical cancer management. We investigated the ability structured illumination microscopy (SIM) to generate images from freshly-obtained breast tissues for structure identification and cancer identification at a speed compatible with potential on-site clinical implementation. We imaged 47 biopsies from patients undergoing a guided breast biopsy procedure using a customized SIM system and a dual-color fluorescent hematoxylin & eosin (H&E) analog. These biopsies had an average size of 0.92 cm2 (minimum 0.1, maximum 4.2) and had an average imaging time of 7:29 (minimum 0:22, maximum 37:44). After imaging, breast biopsies were submitted for standard histopathological processing and review. A board-certified pathologist returned a binary diagnostic accuracy of 96% when compared to diagnoses from gold-standard histology slides, and key tissue features including stroma, vessels, ducts, and lobules were identified from the resulting images.

Pathologic evaluation of lumpectomy resection margins for invasive breast cancer: a single institution's experience

OBJECTIVES

Breast conservation therapy (BCT) or lumpectomy followed by radiation has been established as a preferred treatment for most patients with early-stage invasive breast cancer. About 20-40% of patients after initial lumpectomy will have to undergo re-excision due to a positive margin.

METHODS

To determine the factors predicting higher risk of positive resection margin, we retrospectively analyzed 409 patients who underwent initial lumpectomy for invasive breast cancer from January 2019 through November 2022. Based on microscopic examination, the samples were divided into 3 subgroups with positive, close, or clean margins.

RESULTS

Positive margin was more frequently associated with larger tumor size (P<0.0001), specified histologic type (P<0.0001), higher tumor grade (P=0.004), multifocality (P<0.0001), positive lymph node status (P=0.0005), and lymphovascular invasion (P=0.0007). Other factors were not significantly associated with margin status including HER2/ER/PR status, presence of carcinoma in situ component, age at diagnosis, and history of neoadjuvant chemotherapy.

CONCLUSIONS

From the clinical practice of individual institution, identification and comprehensive assessment of these pathologic predictors will be useful for clinical management and intraoperative surgical-decision-making to reduce the rate of re-excision.

Associations of hospital volume and hospital competition with short-term, middle-term and long-term patient outcomes after breast cancer surgery: a retrospective population-based study

OBJECTIVES

For oncological care, there is a clear tendency towards centralisation and collaboration aimed at improving patient outcomes. However, in market-based healthcare systems, this trend is related to the potential trade-off between hospital volume and hospital competition. We analyse the association between hospital volume, competition from neighbouring hospitals and outcomes for patients who underwent surgery for invasive breast cancer (IBC).

OUTCOME MEASURES

Surgical margins, 90 days re-excision, overall survival.

DESIGN, SETTING, PARTICIPANTS

In this population-based study, we use data from the Netherlands Cancer Registry. Our study sample consists of 136 958 patients who underwent surgery for IBC between 2004 and 2014 in the Netherlands.

RESULTS

Our findings show that treatment types as well as patient and tumour characteristics explain most of the variation in all outcomes. After adjusting for confounding variables and intrahospital correlation in multivariate logistic regressions, hospital volume and competition from neighbouring hospitals did not show significant associations with surgical margins and re-excision rates. For patients who underwent surgery in hospitals annually performing 250 surgeries or more, multilevel Cox proportional hazard models show that survival was somewhat higher (HR 0.94). Survival in hospitals with four or more (potential) competitors within 30 km was slightly higher (HR 0.97). However, this effect did not hold after changing this proxy for hospital competition.

CONCLUSIONS

Based on the selection of patient outcomes, hospital volume and regional competition appear to play only a limited role in the explanation of variation in IBC outcomes across Dutch hospitals. Further research into hospital variation for high-volume tumours like the one studied here is recommended to (i) use consistently measured quality indicators that better reflect multidisciplinary clinical practice and patient and provider decision-making, (ii) include more sophisticated measures for hospital competition and (iii) assess the entire process of care within the hospital, as well as care provided by other providers in cancer networks.

Does Breast Cancer Subtype Impact Margin Status in Patients Undergoing Partial Mastectomy?

Background

Molecular subtype in invasive breast cancer guides systemic therapy. It is unknown whether molecular subtype should also be considered to tailor surgical therapy. The present investigation was designed to evaluate whether breast cancer subtype impacted surgical margins in patients with invasive breast cancer stage I through III undergoing breast-conserving therapy.

Methods

Data from 2 randomized trials evaluating cavity shave margins (CSM) on margin status in patients undergoing partial mastectomy (PM) were used for this analysis. Patients were included if invasive carcinoma was present in the PM specimen and data for all 3 receptors (ER, PR, and HER2) were known. Patients were classified as luminal if they were ER and/or PR positive; HER2 enriched if they were ER and PR negative but HER2 positive; and TN if they were negative for all 3 receptors. The impact of subtype on the margin status was evaluated at completion of standard PM, prior to randomization to CSM versus no CSM. Non-parametric statistical analyses were performed using SPSS Version 26.

Results

Molecular subtype was significantly correlated with race ( P = .011), palpability ( P = .007), and grade ( P < .001). Subtype did not correlate with Hispanic ethnicity ( P = .760) or lymphovascular invasion ( P = .756). In this cohort, the overall positive margin rate was 33.7%. This did not vary based on molecular subtype (positive margin rate 33.7% for patients with luminal tumors vs 36.4% for those with TN tumors, P = .425).

Discussion

Molecular subtype does not predict margin status. Therefore, molecular subtype should not, independent of other factors, influence surgical decision-making.

Review of Current Accepted Practices in Identification of the Breast Lumpectomy Tumor Bed

Purpose

Of the 260,000 women diagnosed with breast cancer annually in the United States, more than 60% are treated with breast-conserving surgery or lumpectomy, followed by radiation to decrease the chance of local recurrence. More than 70% of breast cancer recurrences are localized to the original tumor cavity. Hence, targeted radiation therapy after lumpectomy is critical for recurrence prevention. With 30,000 patients annually opting for oncoplastic reconstruction of the breast after lumpectomy to improve cosmesis, the resulting tissue rearrangement increases the difficulty for radiation oncologists to accurately delineate the cavity when planning radiation therapy. Owing to the absence of a standardized protocol, it is important to assess the efficacy of various methods used to mark the tumor cavity for improved delineation.

Methods and Materials

A keyword search and analysis was used to compile relevant articles on PubMed (National Center for Biotechnology Information).

Results

Currently, a common practice for tumor cavity localization is applying titanium surgical clips to the borders of lumpectomy cavity. Tissue movement and seroma formation both impact the positioning of surgical clips within the tumor cavity and lead to significant interobserver variability. Furthermore, the main application of surgical clips is to control the small vessels during surgery, and that can create confusion when the same clips are used for tumor bed localization. All alternative solutions present more precise tumor bed delineation but possess individual concerns with workflow integration, patient comfort, and accuracy. Though liquid-based fiducials were found to be the most effective for delineating tumor cavities, there are still drawbacks for clinical use.

Conclusions

These findings should encourage medical innovators to develop novel techniques for tumor cavity marking to increase delineation accuracy and effectively target at-risk tissue. Future solutions in this space should consider the properties of liquid-based fiducial markers to improve radiation oncologists' ability to precisely delineate the tumor cavity.

Dynamic extracellular matrix stiffening induces a phenotypic transformation and a migratory shift in epithelial cells

Soft tissue tumors, including breast cancer, become stiffer throughout disease progression. This increase in stiffness has been shown to correlate to malignant phenotype and epithelial-to-mesenchymal transition (EMT) in vitro. Unlike current models, utilizing static increases in matrix stiffness, our group has previously created a system that allows for dynamic stiffening of an alginate-matrigel composite hydrogel to mirror the native dynamic process. Here, we utilize this system to evaluate the role of matrix stiffness on EMT and metastasis both in vitro and in vivo. Epithelial cells were seen to lose normal morphology and become protrusive and migratory after stiffening. This shift corresponded to a loss of epithelial markers and gain of mesenchymal markers in both the cell clusters and migrated cells. Furthermore, stiffening in a murine model reduced tumor burden and increased migratory behavior prior to tumor formation. Inhibition of FAK and PI3K in vitro abrogated the morphologic and migratory transformation of epithelial cell clusters. This work demonstrates the key role extracellular matrix stiffening has in tumor progression through integrin signaling and, in particular, its ability to drive EMT-related changes and metastasis.

Near-Infrared Fluorescence Imaging of Breast Cancer and Axillary Lymph Nodes After Intravenous Injection of Free Indocyanine Green

Background

Near-infrared fluorescence imaging (NIRFI) of breast cancer (BC) after the intravenous (IV) injection of free indocyanine green (fICG) has been reported to be feasible. However, some questions remained unclarified.

Objective

To evaluate the distribution of fICG in BC and the axillary lymph nodes (LNs) of women undergoing surgery with complete axillary LN dissection (CALND) and/or selective lymphadenectomy (SLN) of sentinel LNs (NCT no. 01993576 and NCT no. 02027818).

Methods

An intravenous injection of fICG (0.25 mg/kg) was administered to one series of 20 women undergoing treatment with mastectomy, the day before surgery in 5 (group 1) and immediately before surgery in 15 (group 2: tumor localization, 25; and pN+ CALND, 4) as well as to another series of 20 women undergoing treatment with tumorectomy (group 3). A dedicated NIR camera was used for ex vivo fluorescence imaging of the 45 BC lesions and the LNs.

Results

In group 1, two of the four BC lesions and one large pN+ LN exhibited fluorescence. In contrast, 24 of the 25 tumors in group 2 and all of the tumors in group 3 were fluorescent. The sentinel LNs were all fluorescent, as well as some of the LNs in all CALND specimens. Metastatic cells were found in the fluorescent LNs of the pN+ cases. Fluorescent BC lesions could be identified ex vivo on the surface of the lumpectomy specimen in 14 of 19 cases.

Conclusions

When fICG is injected intravenously just before surgery, BC can be detected using NIRFI with high sensitivity, with metastatic axillary LNs also showing fluorescence. Such a technical approach seems promising in the management of BC and merits further investigation.

Routine cavity shaves following breast conserving surgery; friend or foe?

BACKGROUND

Radial margin status is considered one of the most important prognostic predictor for patients undergoing breast-conserving surgery (BCT), not only related to regional recurrence but also to 5y survival, especially in patients with invasive disease.

AIM

While our primary aim was to evaluate whether doing routine radial cavity shaves following at the time of primary conservative breast surgery will decrease the need for a second operation or not, our secondary aim was to assess time added to the operation to resect and mark the radial shaves, as well as patients' satisfaction with the results.

MATERIAL AND METHODS

We have conducted a case series prospective analysis, including158 patients who underwent breast-conserving surgery looking into the histological status of resection margins and radial shaves, added time taken to take and mark the shaves as well as patients' satisfaction.

RESULTS

158 female breast cancer patients have been included in our analysis, the mean age was 56 years; total number of lesions was 160. While 89.3% of lesions were palpable, 10.6% were not requiring wire-guided localisation. Mean tumour size was 24 mm SD 7, final histology revealed that 86.8% lesion was invasive ductal carcinoma, 5.6% invasive lobular carcinoma, 1.2% medullary carcinoma. 12.4% had invasive disease as well as DCIS, and 1.8% had DCIS only with no invasive disease. Mean preoperative breast volume was 723 ml, Mean wide local excision specimen weight was 73 g, and mean shave weight was 1.6 g. Total number of radial margins was 640, 81.8% was clear, 14.6% was close, and 3.4% was involved. Total number of shaves was 640 out of which 98.7% was clear 0.7% was close and 0.4% was involved. Out of the 160 lesions, 3.7% required a second procedure to clear margins, out of which 2.5% had re-excision for close or involved single shaves each while 1.2% had mastectomy due to close or involved two shaves each. Average time utilised in resection of radial shaves and marking was 7 min 0.6% of patients developed a haematoma, 1.8% had a Seroma, and 1.2% had wound infection. Mean hospital stay was 1day SD 1.

CONCLUSION

Routine radial cavity shaves not only ensure microscopic clearance, reduce the need for re-excision with no significant added operating time but also has no impact on patients' satisfaction.

Finite Element Breast Simulation for Sonography Image Registration

In case of female breast cancer, a breast conserving excision is often necessary. For this purpose, information from multiple medical imaging techniques have to be combined. Sonography imaging is essential for dense breast tissue and the only medical imaging technique available during surgery. During sonography of the outer breast quadrants the woman is usually in contralateral posterior oblique position, being in supine orientation while holding her ipsilateral arm over the head. Thus, these images cannot be directly registered with MRI or mammography images because these imaging technologies are performed in other patient positions with hands on the side of the body. Thus, we present a novel Finite Element approach how to enable a sonography image registration by showing the first time how to transfer the supine position with the arm straight on side into a supine position with the ipsilateral arm over the head which can be used to include information from MRI or mammography images. This approach is shown and validated with 3D scanner breast surface data as proof of concept. When comparing the simulation result with a 3D surface scan in supine orientation with the arm over the head, a mean surface distance error of 1.57 mm is achieved.

Breast cancer

Breast cancer is the most frequent malignancy in women worldwide and is curable in ~70-80% of patients with early-stage, non-metastatic disease. Advanced breast cancer with distant organ metastases is considered incurable with currently available therapies. On the molecular level, breast cancer is a heterogeneous disease; molecular features include activation of human epidermal growth factor receptor 2 (HER2, encoded by ERBB2), activation of hormone receptors (oestrogen receptor and progesterone receptor) and/or BRCA mutations. Treatment strategies differ according to molecular subtype. Management of breast cancer is multidisciplinary; it includes locoregional (surgery and radiation therapy) and systemic therapy approaches. Systemic therapies include endocrine therapy for hormone receptor-positive disease, chemotherapy, anti-HER2 therapy for HER2-positive disease, bone stabilizing agents, poly(ADP-ribose) polymerase inhibitors for BRCA mutation carriers and, quite recently, immunotherapy. Future therapeutic concepts in breast cancer aim at individualization of therapy as well as at treatment de-escalation and escalation based on tumour biology and early therapy response. Next to further treatment innovations, equal worldwide access to therapeutic advances remains the global challenge in breast cancer care for the future.

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.