Cancer-specific dual-factor cascade recognition fluorescent probe for imaging and tumor diagnosis

Herein, we developed a dual-factor recognition activatable probe, S1-F, which accurately lights up Bcl-2 and GSH dual-overexpressed cancer tissue with a superior tumor-to-normal tissue (T/N) ratio, highlighting the potential for this probe to be used in the visual diagnosis and imaging-guided surgery of cancer.

Diagnostic accuracy and challenges of intraoperative frozen section evaluation for axillary sentinel lymph node biopsy and breast margins

AIMS

Our study aims to audit and evaluate the accuracy and pitfalls of intraoperative evaluation of frozen sentinel lymph nodes (IOE-FSLN) and resection margins (IOE-FSM) compared to final findings in paraffin sections.

METHODS

A total of 264 cases underwent intraoperative evaluation, encompassing 688 sentinel lymph nodes (SLNs) and 1186 surgical margins. Frozen section (FS) diagnoses were compared with corresponding permanent sections of FS (PFS). Sensitivity, specificity, false-negative rate, false-positive rate, and concordance rates were assessed. Cases with discrepancies underwent a detailed histological review.

RESULTS

The study predominantly comprised cases of invasive breast carcinoma (IBC) (74%). For FSLN reporting, sensitivity was 88.1%, specificity 100%, and FS-PFS concordance 99.0%. FSM reporting showed sensitivity of 85.0%, specificity 99.9%, and concordance 98.4%. Sampling errors accounted for 86% (FSLN) and 88% (FSM) of discrepancies, with interpretive errors present in 1/7 FSLN and in 2/17 FSM cases. The shave margin method demonstrated a higher false-negative rate in FSM reporting. The rate of final positive margins was reduced from 21.3% to 11.4% when IOE-FSM was utilized.

CONCLUSION

IOE-FSLN and IOE-FSM showed high reliability in guiding intraoperative decisions for axillary lymph node dissection and achieving free surgical margins in one-stage surgeries. However, limitations include challenges in distinguishing metastatic carcinoma from benign mimics in FSLN and diagnosing certain features such as IBC with post-treatment changes, invasive lobular carcinoma in FSLN and FSM; IBC rich in tumour-infiltrating lymphocytes, low-grade (DCIS/IBC in FSM) without immunohistochemical studies.

Improved Rate of Negative Margins for Inflammatory Breast Cancer Using Intraoperative Frozen Section Analysis

BACKGROUND

Inflammatory breast cancer (IBC) is a rare and aggressive form of breast cancer with a poor survival rate. Modified radical mastectomy (MRM) with negative pathologic margins is critical for improved survival. We aim to study the potential benefit of intraoperative frozen section analysis (FSA) to improve disease-free margins.

METHODS

This prospective, monocentric study included 19 patients who underwent MRM for IBC. For each patient, a 2 mm continuous skin edge was sent for FSA to guide further resection. The rate of tumor-free margins and the concurrence between the FSA and permanent pathological results were analyzed.

RESULTS

Overall, 15 of the 19 patients achieved negative margins, including four patients who would have had positive margins without FSA. The odds ratio of achieving a negative final margin with FSA was infinity (p = 0.031), and there was a strong agreement between the FSA and permanent pathological results (Kappa-0.83; p < 0.0001).

CONCLUSIONS

The FSA technique decreased the number of positive margins in IBC patients undergoing MRM, thereby potentially reducing the need for re-operation, allowing immediate wound closure, and preventing delays in the administration of adjuvant radiation therapy. More extensive trials are warranted to establish the use of intraoperative FSA in IBC treatment.

The impact of intraoperative cavity shaving on re-excision rates in breast-conserving surgery

BACKGROUND AND OBJECTIVES

This trial aimed to investigate the effects of circumferential shaving on reducing the reoperation rates during breast-conserving surgery (BCS).

METHODS

In the study, before 2014, 404 (39.9%) breast cancers (BCs) out of a total of 1012 BCs underwent BCS without intraoperative cavity shaving (ICS) and constituted the no-ICS group. After this date, ICS was added to 608 (60.1%) BCSs (ICS group) and intraoperative margin analysis was not requested from pathologists during these second BCS procedures.

RESULTS

The patient and BC characteristics in the no-ICS and ICS groups were similar. Carcinoma detection at the margin and reoperation rates were 13.9% in the no-ICS group and 7.6% in the ICS group (p = 0.001). No significant difference was detected between patients who underwent BCS with intraoperative frozen section analysis (FSA) and patients who underwent BCS with additional ICS (5.6% vs. 7.6%, p = 0.383).

CONCLUSIONS

ICS decreased the rates of positive margins and reoperations among patients with BCS to an acceptable level compared with intraoperative FSA. It may be concluded that ICS is feasible to achieve BC margin control.

Development of an intraoperative breast cancer margin assessment method using quantitative fluorescence measurements

Breast-conserving surgery has become the preferred treatment method for breast cancer. Surgical margin assessment is performed during surgery, as it can reduce local recurrence in the preserved breast. Development of reliable and lower-cost ex vivo cancer detection methods would offer several benefits for patient care. Here, a practical and quantitative evaluation method for the ex vivo fluorescent diagnosis of breast lesions was developed and confirmed through a three-step clinical study. Gamma-glutamyl-hydroxymethyl rhodamine green (gGlu-HMRG) has been reported to generate fluorescence in breast lesions. Using this probe, we constructed a reliable and reproducible procedure for the quantitative evaluation of fluorescence levels. We evaluated the reliability of the method by considering reproducibility, temperature sensitivity, and the effects of other clinicopathological factors. The results suggest that the fluorescence increase of gGlu-HMRG is a good indicator of the malignancy of breast lesions. However, the distributions overlapped. A 5 min reaction with this probe could be used to distinguish at least part of the normal breast tissue. This method did not affect the final pathological examination. In summary, our results indicate that the methods developed in this study may serve as a feasible intraoperative negative-margin assessment tool during breast-conserving surgery.

Label-free multiphoton excitation imaging as a promising diagnostic tool for breast cancer

Histopathological diagnosis is the ultimate method of attaining the final diagnosis; however, the observation range is limited to the two‐dimensional plane, and it requires thin slicing of the tissue, which limits diagnostic information. To seek solutions for these problems, we proposed a novel imaging‐based histopathological examination. We used the multiphoton excitation microscopy (MPM) technique to establish a method for visualizing unfixed/unstained human breast tissues. Under near‐infrared ray excitation, fresh human breast tissues emitted fluorescent signals with three major peaks, which enabled visualizing the breast tissue morphology without any fixation or dye staining. Our study using human breast tissue samples from 32 patients indicated that experienced pathologists can estimate normal or cancerous lesions using only these MPM images with a kappa coefficient of 1.0. Moreover, we developed an image classification algorithm with artificial intelligence that enabled us to automatically define cancer cells in small areas with a high sensitivity of ≥0.942. Taken together, label‐free MPM imaging is a promising method for the real‐time automatic diagnosis of breast cancer.

Application of Intraoperative Mass Spectrometry and Data Analytics for Oncological Margin Detection, A Review

OBJECTIVE

A common phase of early-stage oncological treatment is the surgical resection of cancerous tissue. The presence of cancer cells on the resection margin, referred to as positive margin, is correlated with the recurrence of cancer and may require re-operation, negatively impacting many facets of patient outcomes. There exists a significant gap in the surgeons ability to intraoperatively delineate between tissues. Mass spectrometry methods have shown considerable promise as intraoperative tissue profiling tools that can assist with the complete resection of cancer. To do so, the vastness of the information collected through these modalities must be digested, relying on robust and efficient extraction of insights through data analysis pipelines.

METHODS

We review clinical mass spectrometry literature and prioritize intraoperatively applied modalities. We also survey the data analysis methods employed in these studies.

RESULTS

Our review outlines the advantages and shortcomings of mass spectrometry imaging and point-based tissue probing methods. For each modality, we identify statistical, linear transformation and machine learning techniques that demonstrate high performance in classifying cancerous tissues across several organ systems. A limited number of studies presented results captured intraoperatively.

CONCLUSION

Through continued research of data centric techniques, like mass spectrometry, and the development of robust analysis approaches, intraoperative margin assessment is becoming feasible.

SIGNIFICANCE

By establishing the relatively short history of mass spectrometry techniques applied to surgical studies, we hope to inform future applications and aid in the selection of suitable data analysis frameworks for the development of intraoperative margin detection technologies.

Rapid visualization of mammary gland tumor lesions of dogs using the enzyme-activated fluorogenic probe; γ-glutamyl hydroxymethyl rhodamine green

Since gamma-glutamyl transpeptidase (GGT) is highly and locally expressed in human breast cancer, a GGT-enzymatically activatable fluorescent probe, gamma-glutamyl hydroxymethyl rhodamine green (gGlu-HMRG), has been developed to detect the human breast cancer area with high performance. In this study, GGT expression and the efficacy of gGlu-HMRG on visualization were investigated in canine mammary gland tumors (MGT). Seventeen non-fixed fresh-frozen MGT specimens and each peritumoral control tissue were utilized. The GGT mRNA levels were highly observed in the tumor specimens compared with the control. GGT immunostaining was mostly observed on the cell membrane and cytosol of the alveolar and duct mammary epithelium of MGT tissues. These signals were strongly positive in several cases while they were mild to not observed in other cases. When gGlu-HMRG solution was dropped to the non-fixed tissue pieces of MGT or control tissues, the fluorescence intensities (FIs) were measured using Maestro in-vivo imaging device. FIs in MGT tissues were significantly higher than each control tissue 20 min after treatment. Based on Youden index method said that the maximum sensitivity and specificity of FI was 82.4% and 82.4%. These findings suggest that GGT is highly expressed in several MGTs in dogs and gGlu-HMRG could visualize at least a part of MGT tissues in dogs. Nevertheless, it should be needed to assess the false-negative areas more carefully in canine than human cases.

Diagnostic Value of Intraoperative Frozen Section in Breast-Conserving Surgery: A Systematic Review and Meta-analysis

Context: According to previous studies, using the frozen section procedure during breast surgery reduces the rate of error and the need for re-surgery. We aimed at performing a comprehensive systematic review and meta-analysis to provide reliable evidence on the diagnostic value of frozen section procedures in breast-conserving surgery (BCS). Data Sources: A thorough search was performed in PubMed, Embase, Cochrane Library, and Web of Science databases for human diagnostic studies that used the frozen section in BCS. Meta-analyses were done to find the sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), and negative likelihood ratio (NLR). Study Selection: Human diagnostic studies used the frozen section in breast-conserving surgery and studies that reported the sensitivity and specificity of the frozen section in BCS or contained data that could be calculated the desired parameters were selected for this meta-analysis. Data Extraction: Assessment of studies quality was done and data was extracted from included papers. Then, the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool was used to assess the quality of included papers. Results: Thirty-five papers were entered into our study. The meta-analysis indicated the high sensitivity (83.47, 95%CI 79.61 - 87.32) and specificity (99.29, 95%CI 98.89 - 99.68) for the frozen section in BCS, which resulted in an accuracy of 93.77 (95%CI 92.45 - 95.10). We also found a significant PPV (93.26, 95%CI 91.25 - 95.27), NPV (92.17, 95%CI 90.22 - 94.11), PLR (7.99, 95%CI 6.01 - 9.96), and NLR (0.18, 95%CI 0.14 - 0.23). Conclusions: The findings showed that intraoperative frozen section analysis has high sensitivity and specificity for evaluating lumpectomy margins in patients with early-stage breast cancer and significantly reduces the need for re-operation. Accordingly, re-operation costs are not imposed on the patient and reduce the anxiety of the patients.

Rapid and Sensitive Detection of Cancer Cells with Activatable Fluorescent Probes for Enzyme Activity

Fluorescence (FL)-guided detection of cancer is one of the most promising approaches to achieve intraoperative assessment of surgical margins. Enzymes, such as aminopeptidase, carboxypeptidase, and glycosidase, whose activities are increased in cancer, have attracted great interest as imaging targets for rapid and sensitive visualization of cancerous tissues with fluorescent probes. Activatable probes, which are initially nonfluorescent but become strongly fluorescent upon rapid one-step cleavage of their substrate moiety by the target enzyme, are especially promising for practical clinical application during surgical or endoscopic procedures due to the highly amplified FL change generated by enzyme-catalyzed turnover at lesion sites. Here, we describe robust protocols for using activatable fluorescent probes targeting cancer-associated enzyme activities to visualize cultured cancer cells, metastatic cancer in a mouse model, and cancerous lesions in surgical specimens from patients.

Rapid and Accurate Visualization of Breast Tumors with a Fluorescent Probe Targeting α-Mannosidase 2C1

Accurate detection of breast tumors and discrimination of tumor from normal tissues during breast-conserving surgery are essential to reduce the risk of misdiagnosis or recurrence. However, existing probes show substantial background signals in normal breast tissues. In this study, we focus on glycosidase activities in breast tumors. We synthesized a series of 12 fluorescent probes and performed imaging-based evaluation on surgically resected human breast specimens. Among them, the α-mannosidase-reactive fluorescent probe HMRef-αMan detected breast cancer with 90% sensitivity and 100% specificity. We identified α-mannosidase 2C1 as the target enzyme and confirmed its overexpression in various breast tumors. We found that fibroadenoma, the most common benign breast lesion in young woman, tends to have higher α-mannosidase 2C1 activity than malignant cancer. Combined application of green-emitting HMRef-αMan and a red-emitting γ-glutamyltranspeptidase probe enabled efficient dual-color, dual-target optical discrimination of malignant and benign tumors.

Intraoperative Pathologic Margin Analysis and Re-Excision to Minimize Reoperation for Patients Undergoing Breast-Conserving Surgery

BACKGROUND

Reoperation rates following breast-conserving surgery (BCS) range from 10 to 40%, with marked surgeon and institutional variation.

OBJECTIVE

The aim of this study was to identify factors associated with intraoperative margin re-excision, evaluate for any differences in local recurrence based on margin re-excision and determine reoperation rates with use of intraoperative margin analysis.

PATIENTS AND METHODS

We analyzed consecutive patients with ductal carcinoma in situ (DCIS) or invasive breast cancer who underwent BCS at our institution between 1 January 2005 and 31 December 2016. Routine intraoperative frozen section margin analysis was performed and positive or close margins were re-excised intraoperatively. Univariate analysis was used to compare margin status and the Kaplan-Meier method was used to compare recurrence. Multivariable logistic regression was utilized to analyze factors associated with re-excision.

RESULTS

We identified 3201 patients who underwent BCS-688 for DCIS and 2513 for invasive carcinoma. Overall, 1513 (60.2%) patients with invasive cancer and 434 (63.1%) patients with DCIS had close or positive margins that underwent intraoperative re-excision. Margin re-excision was associated with larger tumor size in both groups. The permanent pathology positive margin rate among all patients was 1.2%, and the 30-day reoperation rate for positive margins was 1.1%. Five-year local recurrence rates were 0.6% and 1.2% for patients with DCIS and invasive cancer, respectively. There was no difference in recurrence between patients with and without intraoperative margin re-excision (p = 0.92).

CONCLUSION

Both DCIS and invasive carcinoma had similar rates of intraoperative margin re-excision. Although intraoperative margin re-excision was common, the reoperation rate was extremely low and there was no difference in recurrence between those with or without intraoperative re-excision.

Dermoglandular rotation flap with subaxillary advancement flap as an oncoplastic technique for breast cancer

We propose a novel oncoplastic surgical technique, dermoglandular rotation flap with subaxillary advancement flap, as a feasible one-stage operation. Breast conserving surgery, incorporating the dermoglandular rotation flap with subaxillary advancement flap, was performed in 49 female patients with breast cancer, between January and December 2015. After a full-thickness fibroglandular resection including the tumor, an inferior- or a superior-based rotation flap was performed according to the location of the defect. The subaxillary flap consisted of skin, dermis, and subcutaneous fat tissue and was mobilized from the chest wall musculature. Since subaxillary skin has greater redundancy, it can be easily moved to reach the lateral aspect of the breast. Approximation of the subaxillary flap to the lateral side of rotated dermoglandular flap served to relieve skin tension and avoid displacement of the nipple-areola complex (NAC). Consequently, there was wider dermoglandular tissue rotation and efficient filling of defect without any significant postoperative deformity. The mean follow-up period was 46.5 ± 3.1 months (range, 42.4-52.1 months). Mean tumor size, on pathology, was 2.1 cm (range, 0.4-6.0). Mean excised breast tissue weight was 78.4 g (range, 28.6-195.0). More than half of the patients (51%) studied had excised breast tissue weighing more than 80 g. None of the included patients had positive surgical margins in final pathologic reports. Most patients answered excellent or good for self-estimated cosmetic outcomes including symmetry of the breast and NAC, breast shape, scarring, and overall satisfaction. A modified dermoglandular rotation flap technique along with subaxillary advancement flap is a feasible and effective oncoplastic technique for breast cancers.

Multicenter Phase II Study of Intraoperative Radiotherapy of Early Breast Cancer: Ipsilateral Tumor Recurrence

BACKGROUND

We performed a multicenter phase II study on the efficacy and safety of intraoperative radiotherapy (IORT) as partial breast irradiation using multiple devices.

METHODS

The primary endpoint was ipsilateral breast tumor recurrence (IBTR). Key inclusion criteria were T < 2.5 cm, age > 50 years, surgical margin > 1 cm, intraoperative pathologically free margins, and sentinel node negative. After resection of the tumor, radiation at 21 Gy was delivered directly to the mammary gland employing an electron linear accelerator in the operating room, otherwise the patient was transported from the surgical suite to the radiation room.

RESULTS

Overall, 142 patients were enrolled in this study and 129 underwent IORT. Stage 0: n = 4 (3.1%); stage I: n = 98 (76.0%); and stage IIA: n = 27 (20.9%). Luminal type: n = 116 (89.9%); triple-negative: n = 9 (7.0%); and human epidermal growth factor receptor 2: n = 4 (3.1%). Median follow-up time was 59.5 months (range 27.5-99.0), and the rate of IBTR was 3.1% (95% confidence interval 0.9-7.8). The toxicities included fibrosis in deep-connective tissue: grade 1, 78.1%; wound infection: grade 3, 1.6% and grade 2, 1.6%; and soft tissue necrosis: grade 3, 0.8% and grade 2, 0.8%. Recurrence in the breast occurred in four cases; the site of recurrence was just under the skin near the primary tumor site, with similar histology and subtype.

CONCLUSIONS

In this multicenter phase II study, the rate of IBTR was low and IORT at 21 Gy was feasible in properly selected patients. It is important to use a careful surgical technique to reduce local recurrence because the skin is not included in the radiation field of IORT.

Pitfalls on sample preparation for ex vivo imaging of resected cancer tissue using enzyme-activatable fluorescent probes

In vivo and ex vivo fluorescence imaging-assisted surgery can aid in determining the margins of tumors during surgical resection. While a variety of fluorescent probes have been proposed for this task, small molecule enzyme-activatable fluorescent probes are ideal for this application. They are quickly activated at tumor sites and result in bright signal with little background, resulting in high sensitivity. Testing in resected specimens, however, can be difficult. Enzymes are usually stable after freezing and thawing but catalytic reactions are generally temperature-dependent. Therefore, tissue sample temperature should be carefully considered. In this study two enzyme activatable probes, γ-glutamylhydroxymethyl rhodamine green (gGlu-HMRG) that reacted with γ-glutamyltransferase and SPiDER-βGal that reacted with β-galactosidase, were employed to determine the effects of temperature on fluorescence signal kinetics in both fresh and frozen and then thawed ex vivo experimental ovarian cancer tissue samples. The results suggest γ-glutamyltransferase was less sensitive to temperature than β-galactosidase. Fresh samples showed higher fluorescence signals of gGlu-HMRG compared with thawed samples likely because the freeze-thaw cycle decreased the rate of internalization of the activated probe into the lysosome. In contrast, no significant difference of SPiDER-βGal fluorescence signal was observed between fresh and frozen tissues. In conclusion, although imaging of fresh samples at 37°C is the best condition for both probes, successful imaging with gGlu-HMRG could be achieved even at room temperature with thawed samples. We demonstrate that temperature regulation and tissue handling of resected tissue are two pitfalls that may influence ex vivo imaging signals with enzyme-activatable fluorescent probes.

Light scattering measured with spatial frequency domain imaging can predict stromal versus epithelial proportions in surgically resected breast tissue

This study aims to determine if light scatter parameters measured with spatial frequency domain imaging (SFDI) can accurately predict stromal, epithelial, and adipose fractions in freshly resected, unstained human breast specimens. An explicit model was developed to predict stromal, epithelial, and adipose fractions as a function of light scattering parameters, which was validated against a quantitative analysis of digitized histology slides for N  =  31 specimens using leave-one-out cross-fold validation. Specimen mean stromal, epithelial, and adipose volume fractions predicted from light scattering parameters strongly correlated with those calculated from digitized histology slides (r  =  0.90, 0.77, and 0.91, respectively, p-value <1  ×  10  -  6). Additionally, the ratio of predicted epithelium to stroma classified malignant specimens with a sensitivity and specificity of 90% and 81%, respectively, and also classified all pixels in malignant lesions with 63% and 79%, at a threshold of 1. All specimens and pixels were classified as malignant, benign, or fat with 84% and 75% accuracy, respectively. These findings demonstrate how light scattering parameters acquired with SFDI can be used to accurately predict and spatially map stromal, epithelial, and adipose proportions in fresh unstained, human breast tissue, and suggest that these estimations could provide diagnostic value.

A topically-sprayable, activatable fluorescent and retaining probe, SPiDER-βGal for detecting cancer: Advantages of anchoring to cellular proteins after activation

SPiDER-βGal is a newly-developed probe that is activated by β-galactosidase and is then retained within cells by anchoring to intracellular proteins. Previous work has focused on gGlu-HMRG, a probe activated by γ-glutamyltranspeptidase, which demonstrated high sensitivity for the detection of peritoneal ovarian cancer metastases in an animal model. However, its fluorescence, after activation by γ-glutamyltranspeptidase, rapidly declines over time, limiting the actual imaging window and the ability to define the border of lesions. The purpose of this study is to compare the fluorescence signal kinetics of SPiDER-βGal with that of gGlu-HMRG using ovarian cancer cell lines in vitro and ex vivo tissue imaging. In vitro removal of gGlu-HMRG resulted in a rapid decrease of fluorescence intensity followed by a more gradual decrease up to 60 min while there was a gradual increase in fluorescence up to 60 min after removal of SPiDER-βGal. This is most likely due to internalization and retention of the dye within cells. This was also confirmed ex vivo tissue imaging using a red fluorescence protein (RFP)-labeled tumor model in which the intensity of fluorescence increased gradually after activation of SPiDER-βGal. Additionally, SPiDER-βGal resulted in intense enhancement within the tumor due to the high target-to-background ratio, which extended up to 60 min after activation. In contrast, gGlu-HMRG fluorescence resulted in decreasing fluorescence over time in extracted tumors. Thus, SPiDER-βGal has the advantages of higher signal with more signal retention, resulting in improved contrast of the tumor margin and suggesting it may be an alternative to existing activatable probes.

Breast Specimen Processing and Reporting With an Emphasis on Margin Evaluation: A College of American Pathologists Survey of 866 Laboratories

CONTEXT

- The College of American Pathologists (CAP) developed protocols for reporting pathologic characteristics of breast cancer specimens, including margin status. The Society of Surgical Oncology (SSO) and the American Society for Radiation Oncology (ASTRO) published treatment guidelines regarding margins in patients with invasive cancer; and SSO, ASTRO, and the American Society of Clinical Oncology (ASCO) recently published guidelines for patients with ductal carcinoma in situ.

OBJECTIVE

- To assess current practices among pathologists with regard to the processing/reporting of breast specimens, assess compliance with CAP cancer protocols, and assess alignment with SSO/ASTRO and SSO/ASTRO/ASCO guidelines.

DESIGN

- A survey concerning breast specimen processing/reporting was distributed to pathologists enrolled in the CAP Performance Improvement Program in Surgical Pathology.

RESULTS

- Ninety-four percent (716 of 764 respondents) and 91% (699 of 769 respondents) define positive margins as "tumor on ink" for invasive cancer and ductal carcinoma in situ, respectively, in compliance with CAP cancer protocols and with SSO/ASTRO and SSO/ASTRO/ASCO guidelines. Of 791 respondents who provided details regarding methods for margin evaluation, 608 (77%) exclusively examine perpendicular margins, facilitating guideline compliance. However, 183 of 791 respondents (23%) examine en face margins in at least a subset of specimens, which may preclude guideline compliance in some cases. When separate cavity (shave) margins are examined, while 517 of 586 respondents (88%) ink these specimens, 69 of 586 (12%) do not, and this may also preclude guideline compliance in some cases.

CONCLUSIONS

- A substantial proportion of survey participants report margin status for breast cancer specimens in a manner consistent with CAP cancer protocols, and in alignment with SSO/ASTRO and SSO/ASTRO/ASCO guidelines. However, there are opportunities for some laboratories to modify procedures in order to facilitate more complete adherence to guidelines.

The Usefulness of Intraoperative Circumferential Frozen-Section Analysis of Lumpectomy Margins in Breast-Conserving Surgery

PURPOSE

Intraoperative frozen-section analysis of the lumpect-omy margin during breast-conserving surgery (BCS) is an excellent method in obtaining a clear resection margin. This study aimed to investigate the usefulness of intraoperative circumferential frozen-section analysis (IOCFS) of lumpectomy margin during BCS for breast cancer, and to find factors that increase the conversion into mastectomy.

METHODS

From 2007 to 2011, 509 patients with breast cancer underwent IOCFS during BCS. The outer surfaces of the shaved lumpectomy margins were evaluated. A negative margin was defined as no ink on the tumor. All margins were evaluated using the permanent section analysis.

RESULTS

Among the 509 patients, 437 (85.9%) underwent BCS and 72 (14.1%) finally underwent mastectomy. Of the 483 pathologically confirmed patients, 338 (70.0%) were true-negative, 24 (5.0%) false-negative, 120 (24.8%) true-positive, and 1 (0.2%) false-positive. Twenty-four patients (4.7%) among total 509 patients had undetermined margins as either atypical ductal hyperplasia or ductal carcinoma in situ in the first IOCFS. The IOCFS has an accuracy of 94.8% with 83% sensitivity, 99.7% specificity, 93.4% negative predictive value, and 99.2% positive predictive value. Sixty-three cases (12.4%) were converted to mastectomy, the first intraoperatively. Of the 446 (87.6%) patients who successfully underwent BCS, 64 patients received additional excisions and 32 were reoperated to achieve clear margin (reoperation rate, 6.3%). Twenty-three of the reoperated patients underwent re-excisions using the second intraoperative frozen section analysis, and achieved BCS. Nine cases were additionally converted to mastectomy. No significant differences in age, stage, and biological factors were found between the BCS and mastectomy cases. Factors such as invasive lobular carcinoma, multiple tumors, large tumor, and multiple excisions increased the conversion to mastectomy.

CONCLUSION

The IOCFS analysis during BCS is useful in evaluating lumpectomy margins and preventing reoperation.

Frozen sections in patients undergoing breast conserving surgery at a single ambulatory surgical center: 5 year experience

OBJECTIVES

To evaluate outcomes of our breast frozen section (FS) practice in its first 5 years, including our specialized FS of margins (FSM) procedure for breast conserving therapy (BCT) patients.

METHODS

One thousand two hundred and forty eight patients undergoing 1303 breast FSM and/or sentinel lymph node (SLN) FS were included. Clinicopathologic features were assessed by chart review.

RESULTS

Use of SLN FS declined, from 43.5% of FS cases before to 19.2% of FS cases after 2012. FSM patients had a decline in overall reexcision to 12.3% in 2013-2014 (p = 0.063). There was also decline in reexcision for focally close margins (p < 0.0001) but no change in reexcision for extensively close margins. Reexcision was significantly associated with lobular subtype, multifocality and larger (≥T2) size. False negative FSM cases were most often influenced by extensively close or positive final (reexcised) margins sent for permanent section only (96/148; 64.9%).

CONCLUSIONS

Despite changing surgical practices, FSM remains a valuable service that reduces reexcision in BCT patients.

Intraoperative Margin Management in Breast-Conserving Surgery: A Systematic Review of the Literature

BACKGROUND

Breast surgeons have a wide variety of intraoperative techniques available to help achieve low rates for positive margins of excision, with variable levels of evidence.

METHODS

A systematic review of the medical literature from 1995 to July 2016 was conducted, with 434 abstracts identified and evaluated. The analysis included 106 papers focused on intraoperative management of breast cancer margins and contained actionable data.

RESULTS

Ultrasound-guided lumpectomy for palpable tumors, as an alternative to palpation guidance, can lower positive margin rates, but the effect when used as an alternative to wire localization (WL) for nonpalpable tumors is less certain. Localization techniques such as radioactive seed localization and radioguided occult lesion localization were found potentially to lower positive margin rates as alternatives to WL depending on baseline positive margin rates. Intraoperative pathologic methods including gross histology, frozen section analysis, and imprint cytology all have the potential to lower the rates of positive margins. Cavity-shave margins and the Marginprobe device both lower rates of positive margins, with some potential for negative cosmetic effects. Specimen radiography and multiple miscellaneous techniques did not affect positive margin rates or provided too little evidence for formation of a conclusion.

CONCLUSIONS

A systematic review of the literature showed evidence that several intraoperative techniques and actions can lower the rates of positive margins. These results are presented together with graded recommendations.

The Efficacy of Intraoperative Frozen Section Analysis During Breast-Conserving Surgery for Patients with Ductal Carcinoma In Situ

INTRODUCTION

Recently, the incidence of ductal carcinoma in situ (DCIS), a noninvasive breast malignancy, has increased. This has resulted in an increase in the incidence of breast-conserving surgery (BCS). Numerous studies have suggested that intraoperative frozen section analysis (IFSA) could reduce the rate of additional excisions required to obtain adequate resection margins. However, DCIS is a known risk factor for positive margin status during BCS. Furthermore, some authors have concluded that IFSA may not be reliable for the detection of DCIS.

AIM

The aim of this study was to evaluate the safety and efficacy of IFSA in patients with DCIS.

METHODS

The operative and pathological reports of patients with DCIS, who underwent BCS at our institute between 2006 and 2015, were retrospectively reviewed. The results of IFSA and the pathological findings of final reanalyzed frozen tissue specimens were analyzed.

RESULTS

In total, 25 patients were included in our analysis. None of the patients required additional operations. The correct diagnosis rate for IFSA was 89.6%, with a sensitivity and specificity of 60.0% and 95.8%, respectively.

CONCLUSION

IFSA could be beneficial for determining safety resection margins in patients with DCIS.

Extracting structural and functional features of widely distributed biological circuits with single cell resolution via tissue clearing and delivery vectors

The scientific community has learned a great deal from imaging small and naturally transparent organisms such as nematodes and zebrafish. The consequences of genetic mutations on their organ development and survival can be visualized easily and with high-throughput at the organism-wide scale. In contrast, three-dimensional information is less accessible in mammalian subjects because the heterogeneity of light-scattering tissue elements renders their organs opaque. Likewise, genetically labeling desired circuits across mammalian bodies is prohibitively slow and costly via the transgenic route. Emerging breakthroughs in viral vector engineering, genome editing tools, and tissue clearing can render larger opaque organisms genetically tractable and transparent for whole-organ cell phenotyping, tract tracing and imaging at depth.

Oncoplastic breast conserving surgery: Volume replacement vs. volume displacement

Oncoplastic breast conserving surgery (BCS) has emerged as a third option between conventional BCS and mastectomy. Oncoplastic BCS includes two fundamentally different approaches: volume replacement and volume displacement. The former involves partial mastectomy and immediate reconstruction of the breast with the transposition of autologous tissue from elsewhere, while the latter involves partial mastectomy and using the remaining breast tissue to fill the defect resulting from extirpation of the tumor. There are several benefits associated with oncoplastic BCS. First, it allows partial mastectomy without cosmetic penalties, and can achieve better cosmetic outcomes than total mastectomy with immediate breast reconstruction. Second, it avoids the need for total mastectomy in an increasing number of patients without compromising local control. Third, partial breast reconstruction is less extensive and has fewer complications than conventional procedures. Partial mastectomy and partial breast reconstruction can be carried out either simultaneously as a one-stage procedure, or using a two-stage approach. Although patients prefer a one-stage procedure, it requires intraoperative confirmation of complete tumor excision using frozen-section analysis. Moreover, oncoplastic BCS requires combined skills, knowledge, and understanding of both oncological and plastic surgeries, which may be optimally achieved by an oncoplastic surgeon.

Whole-body tissue stabilization and selective extractions via tissue-hydrogel hybrids for high-resolution intact circuit mapping and phenotyping

To facilitate fine-scale phenotyping of whole specimens, we describe here a set of tissue fixation-embedding, detergent-clearing and staining protocols that can be used to transform excised organs and whole organisms into optically transparent samples within 1-2 weeks without compromising their cellular architecture or endogenous fluorescence. PACT (passive CLARITY technique) and PARS (perfusion-assisted agent release in situ) use tissue-hydrogel hybrids to stabilize tissue biomolecules during selective lipid extraction, resulting in enhanced clearing efficiency and sample integrity. Furthermore, the macromolecule permeability of PACT- and PARS-processed tissue hybrids supports the diffusion of immunolabels throughout intact tissue, whereas RIMS (refractive index matching solution) grants high-resolution imaging at depth by further reducing light scattering in cleared and uncleared samples alike. These methods are adaptable to difficult-to-image tissues, such as bone (PACT-deCAL), and to magnified single-cell visualization (ePACT). Together, these protocols and solutions enable phenotyping of subcellular components and tracing cellular connectivity in intact biological networks.

Intraoperative Assessment of Final Margins with a Handheld Optical Imaging Probe During Breast-Conserving Surgery May Reduce the Reoperation Rate: Results of a Multicenter Study

BACKGROUND

A multicenter, prospective, blinded study was performed to test the feasibility of using a handheld optical imaging probe for the intraoperative assessment of final surgical margins during breast-conserving surgery (BCS) and to determine the potential impact on patient outcomes.

METHODS

Forty-six patients with early-stage breast cancer (one with bilateral disease) undergoing BCS at two study sites, the Johns Hopkins Hospital and Anne Arundel Medical Center, were enrolled in this study. During BCS, cavity-shaved margins were obtained and the final margins were examined ex vivo in the operating room with a probe incorporating optical coherence tomography (OCT) hardware and interferometric synthetic aperture microscopy (ISAM) image processing. Images were interpreted after BCS by three physicians blinded to final pathology-reported margin status. Individual and combined interpretations were assessed. Results were compared to conventional postoperative histopathology.

RESULTS

A total of 2,191 images were collected and interpreted from 229 shave margin specimens. Of the eight patients (17 %) with positive margins (0 mm), which included invasive and in situ diseases, the device identified all positive margins in five (63%) of them; reoperation could potentially have been avoided in these patients. Among patients with pathologically negative margins (>0 mm), an estimated mean additional tissue volume of 10.7 ml (approximately 1% of overall breast volume) would have been unnecessarily removed due to false positives.

CONCLUSIONS

Intraoperative optical imaging of specimen margins with a handheld probe potentially eliminates the majority of reoperations.

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.

Rapid intraoperative visualization of breast lesions with γ-glutamyl hydroxymethyl rhodamine green

We previously developed γ-glutamyl hydroxymethyl rhodamine green (gGlu-HMRG) as a tool to detect viable cancer cells, based on the fact that the enzyme γ-glutamyltranspeptidase (GGT) is overexpressed on membranes of various cancer cells, but is not expressed in normal tissue. Cleavage of the probe by GGT generates green fluorescence. Here, we examined the feasibility of clinical application of gGlu-HMRG during breast-conserving surgery. We found that fluorescence derived from cleavage of gGlu-HMRG allowed easy discrimination of breast tumors, even those smaller than 1 mm in size, from normal mammary gland tissues, with 92% sensitivity and 94% specificity, within only 5 min after application. We believe this rapid, low-cost method represents a breakthrough in intraoperative margin assessment during breast-conserving surgery.

Standardized processing of native tissue in breast pathology

In breast surgery, replacement of intraoperative frozen section by core needle and vacuum biopsies hampers collections of unfixed breast specimens. We practice immediate intraoperative macroscopic analysis of resection margins and vacuum-cooling of breast specimens to enable native tissue asservation for assessment of biological markers and tissue banking of tumor tissue. In addition, slicing of native tissue before formalin fixation guarantees a standardized and uniform fixation. Starting in 2013, more than 350 breast specimens were processed as native specimens in the Institute of Pathology of Hannover Medical School. Breast specimens with an invasive carcinoma and request of an intraoperative resection margin assessment were processed with an immediate intraoperative pathological analysis. All other breast specimens without assessment of an intraoperative resection margin were vacuum-fixed processed. In all cases, native tissue for biomarker analyses and tumor banking could be preserved.

Is intraoperative frozen section analysis of reexcision specimens of value in preventing reoperation in breast-conserving therapy?

OBJECTIVES

A prior study at our institution showed a marked reduction in reoperation for margin reexcision following the development of an intraoperative frozen section evaluation of margins (FSM) practice on lumpectomy specimens from patients undergoing breast-conserving therapy (BCT). This study aimed to examine the frequency of FSM utilization, FSM pathology performance, and outcomes for BCT patients undergoing margin reexcision only.

METHODS

Consecutive reexcision-only specimens were reviewed from a 40-month period following the development of the FSM practice. Clinicopathologic features and patient outcomes were assessed.

RESULTS

FSM was performed in 46 (30.7%) of 150 reexcision-only operations. Of the 46 operations with FSM, there were 28 (60.9%) true-negative, 12 (26.1%) true-positive, six (13.0%) false-negative, and no false-positive cases. There was no difference in further reexcision, total operations, or conversion to mastectomy among patients with and without FSM. Need for further reexcision was significantly associated with tumor multifocality (P = .008).

CONCLUSIONS

Despite overall good pathology performance for FSM in reexcision-only specimens, use of FSM did not affect patient outcome. Rather, underlying disease biology appeared most significant in predicting whether adequate surgical margins could be attained.

Assessment of breast pathologies using nonlinear microscopy

Rapid intraoperative assessment of breast excision specimens is clinically important because up to 40% of patients undergoing breast-conserving cancer surgery require reexcision for positive or close margins. We demonstrate nonlinear microscopy (NLM) for the assessment of benign and malignant breast pathologies in fresh surgical specimens. A total of 179 specimens from 50 patients was imaged with NLM using rapid extrinsic nuclear staining with acridine orange and intrinsic second harmonic contrast generation from collagen. Imaging was performed on fresh, intact specimens without the need for fixation, embedding, and sectioning required for conventional histopathology. A visualization method to aid pathological interpretation is presented that maps NLM contrast from two-photon fluorescence and second harmonic signals to features closely resembling histopathology using hematoxylin and eosin staining. Mosaicking is used to overcome trade-offs between resolution and field of view, enabling imaging of subcellular features over square-centimeter specimens. After NLM examination, specimens were processed for standard paraffin-embedded histology using a protocol that coregistered histological sections to NLM images for paired assessment. Blinded NLM reading by three pathologists achieved 95.4% sensitivity and 93.3% specificity, compared with paraffin-embedded histology, for identifying invasive cancer and ductal carcinoma in situ versus benign breast tissue. Interobserver agreement was κ = 0.88 for NLM and κ = 0.89 for histology. These results show that NLM achieves high diagnostic accuracy, can be rapidly performed on unfixed specimens, and is a promising method for intraoperative margin assessment.

The value of intraoperative frozen section analysis for margin status in breast conservation surgery in a nontertiary institution

Introduction. Breast conservation treatment (BCT) for early-stage breast malignancies requires negative margins and good cosmesis. Reoperations may be needed to achieve negative margins, which can have an adverse impact on outcomes. This study was performed to evaluate the efficacy of intraoperative frozen section analysis (IFSA) for margin assessment to reduce excision rates. Methods. All patients treated at the authors' private healthcare facility between 2009 and 2011 for breast cancer were included in the study. Those for whom BCT was intended underwent wide excision with IFSA. Six margins of the excised tissue, and the sentinel lymph node (SLN), where appropriate, were submitted for IFSA. Patient demographics, tumour characteristics, number of operations performed, and outcomes were analysed. Results. Of the 161 patients analysed, 138 (85.7%) had successful breast conservation. Four patients required a reoperation for incomplete surgical extirpation. One had a false negative SLN assessment on IFSA, and was returned to the operating room for an axillary dissection. Three patients required reoperations for inadvertently missed multicentric disease. None had false negative margin evaluation with IFSA necessitating reexcision. Conclusion. The use of IFSA allows low rates of reoperation with BCT. Further research is needed to establish consistency in low reexcision rates for cost-effectiveness and optimum resource allocation.

Multiple margin positivity of frozen section is an independent risk factor for local recurrence in breast-conserving surgery

Purpose

Breast-conserving surgery (BCS) with radiotherapy has become a standard treatment for early stage breast cancer, since the installation of NSABP B-06. One of the serious problems in BCS is that of local recurrence. There are many risk factors for local recurrence, such as large tumor size, multiple tumors, axillary lymph node involvement, young age, high nuclear grade, and so on. The aim of this study is to identify patients with a higher risk of local recurrence of breast cancer.

Methods

Between January 2002 and December 2006, 447 patients with breast cancer, and who had undergone BCS with immediate breast reconstruction, were enrolled in the study. The follow-up period was 5 years from the time of operation and we analyzed local recurrence, disease-free survival (DFS), and overall survival (OS). The analysis included various clinicopathological factors such as age, chemotherapy, radiotherapy, hormone therapy, pathologic characteristics, and margin status. Statistical analysis was performed with log-rank test and Kaplan-Meier method. The p-value <0.05 was considered statistically significant.

Results

The mean follow-up period was 88 months and local recurrence of breast cancer occurred only in 16 cases (3.6%). The actual 5-year DFS, and OS rates were 90.6% and 93.3%, respectively. For the local recurrence of breast cancer, positive margin status, multiple margin positivity, conversed margin cases, T/N stages showed statistical significance in univariate analysis. However, only multiple margin positivity was identified as an independent risk factor for local recurrence in multivariate analysis.

Conclusion

When the multiple margin positivity is diagnosed on intraoperative frozen biopsy, surgeons should consider a much wider excision of the breast and a more aggressive management.

Intraoperative frozen section analysis of margins in breast conserving surgery significantly decreases reoperative rates: one-year experience at an ambulatory surgical center

Intraoperative frozen section (FS) margin evaluation is not common practice for patients undergoing breast conservation therapy (BCT), but offers a significant reduction in reoperation. In this study, a technique to allow for more effective freezing of breast tissue was developed to perform FS evaluation of lumpectomy margins (FSM) for all patients undergoing BCT at an ambulatory surgery center. FS evaluation of sentinel lymph node biopsy specimens was performed concurrently. One hundred eighty-one study and 188 control patients, with and without FS evaluation, were compared. Reexcision was reduced 34% (from 48.9% to 14.9%) and reoperation was reduced 36% (from 55.3% to 19.3%) with FS evaluation. Most of the decrease in reoperative rate was because of a decrease in the need for margin reexcision. The number of patients requiring 1, 2, or 3 operations to complete therapy was 84, 92, and 12, respectively, in the control group, and 146, 33, and 2, respectively, in the study group. Lobular subtype, multifocal disease, and larger tumor size (≥2 cm) were significantly associated with failure of FSM to prevent reoperation, but reoperation rates were still significantly decreased in this subgroup of patients (from 75.5% to 43.8%) with FSM. This study highlights an innovative yet simple and adaptable FS approach that resulted in a nearly 3-fold reduction in reoperation for patients undergoing BCT.

Intraoperative imprint cytology and frozen section pathology for margin assessment in breast conservation surgery: a systematic review

BACKGROUND

Achieving negative surgical margins is critical to minimizing the risk of tumor recurrence in patients undergoing breast conservation surgery (BCS) for a breast malignancy. Our objective was to perform a systematic review comparing reexcision rates, sensitivity and specificity of the intraoperative use of the margin assessment techniques of imprint cytology (IC) and frozen section analysis (FSA), against permanent histopathologic section (PS).

METHODS

The databases PubMed, Web of Knowledge, Cochrane Library and CINAHL Plus were searched for literature published from 1997 to 2011. Original investigations of patients who underwent BCS for breast cancer that evaluated margin assessment with PS and/or IC or FSA were included. Of 182 titles identified, 41 patient cohorts from 37 articles met inclusion criteria: PS (n = 19), IC (n = 7) and FSA (n = 15). Studies were summarized qualitatively using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist for cohort studies and the Strength of Recommendation Taxonomy (SORT) numerical scale for diagnostic studies.

RESULTS

The final reexcision rates after primary BCS were 35 % for PS, 11 % for IC (p = 0.001 vs. PS) and 10 % for FSA (p < 0.0001 vs. PS). For IC, reexcision rates decreased from 26 to 4 % (p = 0.18) and for FSA, reexcision rates decreased from 27 to 6 % (p < 0.0001). The pooled sensitivity of IC and FSA were 72 and 83 %. The pooled specificity of IC and FSA were 97 and 95 %. The average length of each technique was 13 min for IC and 27 min for FSA.

CONCLUSIONS

Patients who underwent BCS with intraoperative IC or FSA to assess negative surgical margins had significantly fewer secondary surgical procedures for excision of their breast malignancies.

[Intraoperative pathological rapid investigations in breast surgery]

In breast surgery intraoperative frozen sections for the diagnosis of malignancy has lost impact and has largely been replaced by preoperative core needle biopsies. Nevertheless, there is still need for immediate pathological investigation of native breast tissue during surgery due to three reasons: (1) macroscopic and microscopic evaluation of resection margins, (2) the histological analysis of sentinel lymph nodes in order to circumvent secondary axillary surgery and (3) the preparation of native tissue for tumor banking or measurement of biomarkers. Because histology provides only a facultative component of immediate pathological examination of breast specimens during surgery, the term frozen section does not seem to be appropriate anymore. Intraoperative evaluation of resection specimens by pathologists provides surgically relevant information immediately, guarantees standardized preparation and fixation of specimens and enables tissue banking of native tissue for assessment of biological markers.

Breast conservation surgery: state of the art

Breast conservation surgery is available to the vast majority of women with breast cancer. The combination of neoadjuvant therapies and oncoplastic surgical techniques allows even large tumours to be managed with a breast-conserving approach. The relationship between breast size and the volume of tissue to be excised determines the need for volume displacement or replacement. Such an approach can also be used in the management of carefully selected cases of multifocal or multicentric breast cancer. The role of novel techniques, such as endoscopic breast surgery and radiofrequency ablation, is yet to be precisely defined.