Intraoperative Margin Assessment Research Articles

VAC temporization pending final margins after suprafascial myxofibrosarcoma excision to reduce the rate of local recurrence.

11573 Background: The microinvasive nature of suprafascial myxofibrosarcoma complicates the accuracy of intraoperative margin assessment, and tumor bed resections after soft tissue reconstruction are unreliable. For the past 3 years we have temporized the excised tumor bed with a wound VAC, delaying soft tissue coverage until final negative margins were achieved. Here, we compare the oncologic/surgical outcomes of suprafascial myxofibrosarcomas managed with VAC temporization (VT) with single-stage excision/reconstruction (SS). Methods: We retrospectively studied suprafascial myxofibrosarcomas managed from 1/1/2000 to 1/1/2019 who received neoadjuvant or adjuvant radiation and had at least 2-years of oncologic follow-up at a tertiary referral cancer center. Our primary outcome was local recurrence. Comparisons were performed using Fisher’s Exact Test or Students t-test. A p-value < 0.05 was considered significant. Results: Fifty-three patients (18 VAC temporized, 35 single stage) were included. While VT patients were older (74.9 ± 10.2 vs. 63.9 ± 13.6, p = 0.003), treatment groups did not significantly differ with respect to comorbidity, tumor volume, stage and grade. VT patients had significantly fewer local recurrences (5.6% vs. 28.6% after SS, p = 0.048) and R1 resections that required an unplanned readmission for tumor bed re-excision (0% vs. 37.1% after SS, p = 0.002). VT required more total surgeries (2.8 ± 0.9 vs. 1.8 ± 0.9 for SS, p = 0.0002). Post-operative infectious and wound complications were equivalent (Table). Conclusions: Our VAC temporization strategy had a significantly lower LR than SS treatment. While high quality multi-institutional validation is required, VT may represent a paradigm shift in the management of myxofibrosarcoma.[Table: see text]

Intraoperative Assessment of Resection Margins in Oral Cavity Cancer: This is the Way.

The goal of head and neck oncological surgery is complete tumor resection with adequate resection margins while preserving acceptable function and appearance. For oral cavity squamous cell carcinoma (OCSCC), different studies showed that only 15%-26% of all resections are adequate. A major reason for the low number of adequate resections is the lack of information during surgery; the margin status is only available after the final histopathologic assessment, days after surgery. The surgeons and pathologists at the Erasmus MC University Medical Center in Rotterdam started the implementation of specimen-driven intraoperative assessment of resection margins (IOARM) in 2013, which became the standard of care in 2015. This method enables the surgeon to turn an inadequate resection into an adequate resection by performing an additional resection during the initial surgery. Intraoperative assessment is supported by a relocation method procedure that allows accurate identification of inadequate margins (found on the specimen) in the wound bed. The implementation of this protocol resulted in an improvement of adequate resections from 15%-40%. However, the specimen-driven IOARM is not widely adopted because grossing fresh tissue is counter-intuitive for pathologists. The fear exists that grossing fresh tissue will deteriorate the anatomical orientation, shape, and size of the specimen and therefore will affect the final histopathologic assessment. These possible negative effects are countered by the described protocol. Here, the protocol for specimen-driven IOARM is presented in detail, as performed at the institute.

Intraoperative Assessment of Resection Margins in Oral Cavity Cancer: This is the Way

The goal of head and neck oncological surgery is complete tumor resection with adequate resection margins while preserving acceptable function and appearance. For oral cavity squamous cell carcinoma (OCSCC), different studies showed that only 15%-26% of all resections are adequate. A major reason for the low number of adequate resections is the lack of information during surgery; the margin status is only available after the final histopathologic assessment, days after surgery. The surgeons and pathologists at the Erasmus MC University Medical Center in Rotterdam started the implementation of specimen-driven intraoperative assessment of resection margins (IOARM) in 2013, which became the standard of care in 2015. This method enables the surgeon to turn an inadequate resection into an adequate resection by performing an additional resection during the initial surgery. Intraoperative assessment is supported by a relocation method procedure that allows accurate identification of inadequate margins (found on the specimen) in the wound bed. The implementation of this protocol resulted in an improvement of adequate resections from 15%-40%. However, the specimen-driven IOARM is not widely adopted because grossing fresh tissue is counter-intuitive for pathologists. The fear exists that grossing fresh tissue will deteriorate the anatomical orientation, shape, and size of the specimen and therefore will affect the final histopathologic assessment. These possible negative effects are countered by the described protocol. Here, the protocol for specimen-driven IOARM is presented in detail, as performed at the institute.

Novel imaging techniques for intraoperative margin assessment in surgical oncology: A systematic review.

Inadequate margins continue to occur frequently in patients who undergo surgical resection of a tumor, suggesting that current intraoperative methods are not sufficiently reliable in determining the margin status. This clinical demand has inspired the development of many novel imaging techniques that could help surgeons with intraoperative margin assessment. This systematic review provides an overview of novel imaging techniques for intraoperative margin assessment in surgical oncology, and reports on their technical properties, feasibility in clinical practice and diagnostic accuracy. PubMed, Embase, Web of Science and the Cochrane library were systematically searched (2013‐2018) for studies reporting on imaging techniques for intraoperative margin assessment. Patient and study characteristics, technical properties, feasibility characteristics and diagnostic accuracy were extracted. This systematic review identified 134 studies that investigated and developed 16 groups of techniques for intraoperative margin assessment: fluorescence, advanced microscopy, ultrasound, specimen radiography, optical coherence tomography, magnetic resonance imaging, elastic scattering spectroscopy, bio‐impedance, X‐ray computed tomography, mass spectrometry, Raman spectroscopy, nuclear medicine imaging, terahertz imaging, photoacoustic imaging, hyperspectral imaging and pH measurement. Most studies were in early developmental stages (IDEAL 1 or 2a, n = 98); high‐quality stage 2b and 3 studies were rare. None of the techniques was found to be clearly superior in demonstrating high feasibility as well as high diagnostic accuracy. In conclusion, the field of imaging techniques for intraoperative margin assessment is highly evolving. This review provides a unique overview of the opportunities and limitations of the currently available imaging techniques.

Performance of Intraoperative Assessment of Resection Margins in Oral Cancer Surgery: A Review of Literature.

IntroductionAchieving adequate resection margins during oral cancer surgery is important to improve patient prognosis. Surgeons have the delicate task of achieving an adequate resection and safeguarding satisfactory remaining function and acceptable physical appearance, while relying on visual inspection, palpation, and preoperative imaging. Intraoperative assessment of resection margins (IOARM) is a multidisciplinary effort, which can guide towards adequate resections. Different forms of IOARM are currently used, but it is unknown how accurate these methods are in predicting margin status. Therefore, this review aims to investigate: 1) the IOARM methods currently used during oral cancer surgery, 2) their performance, and 3) their clinical relevance.MethodsA literature search was performed in the following databases: Embase, Medline, Web of Science Core Collection, Cochrane Central Register of Controlled Trials, and Google Scholar (from inception to January 23, 2020). IOARM performance was assessed in terms of accuracy, sensitivity, and specificity in predicting margin status, and the reduction of inadequate margins. Clinical relevance (i.e., overall survival, local recurrence, regional recurrence, local recurrence-free survival, disease-specific survival, adjuvant therapy) was recorded if available.ResultsEighteen studies were included in the review, of which 10 for soft tissue and 8 for bone. For soft tissue, defect-driven IOARM-studies showed the average accuracy, sensitivity, and specificity of 90.9%, 47.6%, and 84.4%, and specimen-driven IOARM-studies showed, 91.5%, 68.4%, and 96.7%, respectively. For bone, specimen-driven IOARM-studies performed better than defect-driven, with an average accuracy, sensitivity, and specificity of 96.6%, 81.8%, and 98%, respectively. For both, soft tissue and bone, IOARM positively impacts patient outcome.ConclusionIOARM improves margin-status, especially the specimen-driven IOARM has higher performance compared to defect-driven IOARM. However, this conclusion is limited by the low number of studies reporting performance results for defect-driven IOARM. The current methods suffer from inherent disadvantages, namely their subjective character and the fact that only a small part of the resection surface can be assessed in a short time span, causing sampling errors. Therefore, a solution should be sought in the field of objective techniques that can rapidly assess the whole resection surface.

Accuracy of frozen section in intraoperative margin assessment for breast-conserving surgery: A systematic review and meta-analysis.

It is well established that tumor-free margin is an important factor for reducing local recurrence and reoperation rates. This systematic review with meta-analysis of frozen section intraoperative margin assessment aims to evaluate the accuracy, and reoperation and survival rates, and to establish its importance in breast-conserving surgery. A thorough review was conducted in all online publication-databases for the related literature up to March 2020. MeSH terms used: "Breast Cancer", "Segmental Mastectomy" and "Frozen Section". We included the studies that evaluated accuracy of frozen section, reoperation and survival rates. To ensure quality of the included articles, the QUADAS-2 tool (adapted) was employed. The assessment of publication bias by graphical and statistical methods was performed using the funnel plot and the Egger's test. The review protocol was registered in PROSPERO (CRD42019125682). Nineteen studies were deemed suitable, with a total of 6,769 cases. The reoperation rate on average was 5.9%. Sensitivity was 0.81, with a Confidence Interval of 0.79-0.83, p = 0.0000, I2 = 95.1%, and specificity was 0.97, with a Confidence Interval of 0.97-0.98, p = 0.0000, I-2 = 90.8%, for 17 studies and 5,615 cases. Accuracy was 0.98. Twelve studies described local recurrence and the highest cumulative recurrence rate in 3 years was 7.5%. The quality of the included studies based on the QUADAS-2 tool showed a low risk of bias. There is no publication bias (p = 0.32) and the funnel plot showed symmetry. Frozen section is a reliable procedure with high accuracy, sensitivity and specificity in intraoperative margin assessment of breast-conserving surgery. Therefore, this modality of margin assessment could be useful in reducing reoperation rates.

Intraoperative [18F]FDG flexible autoradiography for tumour margin assessment in breast-conserving surgery: a first-in-human multicentre feasibility study

IntroductionIn women undergoing breast-conserving surgery (BCS), 20–25% require a re-operation as a result of incomplete tumour resection. An intra-operative technique to assess tumour margins accurately would be a major advantage. A novel method for intraoperative margin assessment was developed by applying a thin flexible scintillating film to specimens—flexible autoradiography (FAR) imaging. A single-arm, multi-centre study was conducted to evaluate the feasibility of intraoperative [18F]FDG FAR for the assessment of tumour margins in BCS.MethodsEighty-eight patients with invasive breast cancer undergoing BCS received ≤ 300 MBq of [18F]FDG 60–180 min pre-operatively. Following surgical excision, intraoperative FAR imaging was performed using the LightPath® Imaging System. The first 16 patients were familiarisation patients; the remaining 72 patients were entered into the main study. FAR images were analysed post-operatively by three independent readers. Areas of increased signal intensity were marked, mean normalised radiances and tumour-to-tissue background (TBR) determined, agreement between histopathological margin status and FAR assessed and radiation dose to operating theatre staff measured. Subgroup analyses were performed for various covariates, with thresholds set based on ROC curves.ResultsData analysis was performed on 66 patients. Intraoperative margin assessment using FAR was completed on 385 margins with 46.2% sensitivity, 81.7% specificity, 8.1% PPV, 97.7% NPV and an overall accuracy of 80.5%, detecting both invasive carcinoma and DCIS. A subgroup analysis based on [18F]FDG activity present at time of imaging revealed an increased sensitivity (71.4%), PPV (9.3%) and NPV (98.4%) in the high-activity cohort with mean tumour radiance and TBR of 126.7 ± 45.7 photons/s/cm2/sr/MBq and 2.1 ± 0.5, respectively. Staff radiation exposure was low (38.2 ± 38.1 µSv).Conclusion[18F]FDG FAR is a feasible and safe technique for intraoperative tumour margin assessment. Further improvements in diagnostic performance require optimising the method for scintillator positioning and/or the use of targeted radiopharmaceuticals.Trial registration: Identifier: NCT02666079. Date of registration: 28 January 2016. URL: https://clinicaltrials.gov/ct2/show/NCT02666079.ISRCTN registry: Reference: ISRCTN17778965. Date of registration: 11 February 2016. URL: http://www.isrctn.com/ISRCTN17778965.

Clinical integration of fast Raman spectroscopy for Mohs micrographic surgery of basal cell carcinoma.

We present the first clinical integration of a prototype device based on integrated auto-fluorescence imaging and Raman spectroscopy (Fast Raman device) for intra-operative assessment of surgical margins during Mohs micrographic surgery of basal cell carcinoma (BCC). Fresh skin specimens from 112 patients were used to optimise the tissue pre-processing and the Fast Raman algorithms to enable an analysis of complete Mohs layers within 30 minutes. The optimisation allowed >95% of the resection surface area to be investigated (including the deep and epidermal margins). The Fast Raman device was then used to analyse skin layers excised from the most relevant anatomical sites (nose, temple, eyelid, cheek, forehead, eyebrow and lip) and to detect the three main types of BCC (nodular, superficial and infiltrative). These results suggest that the Fast Raman technique is a promising tool to provide an objective diagnosis “tumour clear yes/no” during Mohs surgery of BCC. This clinical integration study is a key step towards a larger scale diagnosis test accuracy study to reliably determine the sensitivity and specificity in a clinical setting.

Optical palpation for tumor margin assessment in breast-conserving surgery.

Intraoperative margin assessment is needed to reduce the re-excision rate of breast-conserving surgery. One possibility is optical palpation, a tactile imaging technique that maps stress (force applied across the tissue surface) as an indicator of tissue stiffness. Images (optical palpograms) are generated by compressing a transparent silicone layer on the tissue and measuring the layer deformation using optical coherence tomography (OCT). This paper reports, for the first time, the diagnostic accuracy of optical palpation in identifying tumor within 1 mm of the excised specimen boundary using an automated classifier. Optical palpograms from 154 regions of interest (ROIs) from 71 excised tumor specimens were obtained. An automated classifier was constructed to predict the ROI margin status by first choosing a circle diameter, then searching for a location within the ROI where the circle was ≥ 75% filled with high stress (indicating a positive margin). A range of circle diameters and stress thresholds, as well as the impact of filtering out non-dense tissue regions, were tested. Sensitivity and specificity were calculated by comparing the automated classifier results with the true margin status, determined from co-registered histology. 83.3% sensitivity and 86.2% specificity were achieved, compared to 69.0% sensitivity and 79.0% specificity obtained with OCT alone on the same dataset using human readers. Representative optical palpograms show that positive margins containing a range of cancer types tend to exhibit higher stress compared to negative margins. These results demonstrate the potential of optical palpation for margin assessment.

Abstract PS3-04: Breast tumor targeted fluorescence guidance for intraoperative margin assessment

Abstract BACKGROUND: A majority of the 270,000 women diagnosed with breast cancer in the United States annually are candidates for breast conserving surgery (lumpectomy), however, up to 30% of patients require reoperation due to positive margins. The ideal resolution is to make residual in-breast disease visible at the time of surgery. The goal of this research is to develop a systemically administered fluorescent molecular imaging agent that is targeted to breast tumors for intraoperative margin assessment using fluorescence guided surgery (FGS). METHODS: To identify targetable cell-surface markers for use in FGS, gene expression profiling of publicly available Affymetrix mRNA microarray data from patients with invasive ductal or invasive lobular carcinoma tumors (n=34) and surrounding normal breast tissues (n=32) was performed. Protein expression of select targets was determined by immunohistochemistry (IHC) staining of patient tissue specimens. A humanized CEACAM6 (carcinoembryonic cell adhesion molecule 6) specific antibody fragment (scFv-Fc [IgG4]) was conjugated to the near-infrared IRDye800CW fluorescent dye (LiCor) by NHS-ester linkage to create CEACAM6-800. The conjugate was characterized for in vitro specificity by immunocytochemistry (ICC) and live cell uptake studies. As proof-of-principle, the conjugate (15 µg) was intravenously injected into nude mice bearing orthotopic human MCF-7 breast cancer mammary fat pad (MFP) xenograft tumors with endogenous expression of CEACAM6. FGS was performed using the “SurgVision” clinical imaging platform (approved for clinical use in Europe) at 24 h post-injection.RESULTS: We identified 263 genes with higher mRNA expression in tumor relative to normal. From this list, we selected 9 genes for confirmation of protein expression by IHC. Of the 9 targets, only CEACAM6 had no protein expression in normal breast tissues and robust expression in ~50% of tumors. ICC staining using the CEACAM6-800 conjugate and multiple human ductal carcinoma tumor cell lines confirmed the cell surface localization of CEACAM6. In live-cell uptake studies, CEACAM6-800 accumulated on the cell surface as early as 10 min after addition to the media and was internalized after 90 min. Blocking studies demonstrated specificity. In the proof-of-principal FGS study, we observed high fluorescence in MCF-7 MFP tumors relative to background and the tumors and their residuals were completely removed in the first attempt. CONCLUSION: We have confirmed CEACAM6 protein as a cell-surface adhesion receptor target for breast cancer FGS. The CEACAM6-800, fluorescent-dye to antibody-fragment conjugate was prepared and tested in vitro for sub-cellular localization and specific uptake. In vivo studies demonstrated specific uptake into MFP tumors and FGS for tumor resection. We are currently performing studies to determine the in vivo pharmacokinetics of CEACAM6-800 uptake and clearance in tumor and normal tissues and pre-clinical post-surgery survival using our pre-clinical models. These studies will enable future translational studies. Citation Format: Narges Tafreshi, Mikalai Budzevich, Weihong Sun, Daruka Mahadevan, Marie Catherine Lee, David L Morse. Breast tumor targeted fluorescence guidance for intraoperative margin assessment [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS3-04.

Abstract PS1-21: Molecular fluorescence-guided surgery using Beva800 for the assessment of tumor margins during breast conserving surgery of patients with primary breast cancer (MARGIN-II)

Abstract Introduction:The goal of breast conserving surgery (BCS) for early breast cancer (EBC) is to remove the tumor and a surrounding rim of normal tissue, while preserving as much of the normal breast tissue as possible. Incomplete resections are associated with higher rates of surgical re-excision. Repeat surgeries are not only a burden to patients physically but also psychologically and can delay recommended adjuvant therapies. Accurate determination of tumor margins during surgery is therefore critical for successful outcome. Breast cancer tissue produces significantly higher amounts of VEGF-A than healthy tissue. VEGF-A stimulates tumor angiogenesis and is therefore an excellent target for molecular imaging techniques. The fluorescence imaging agent bevacizumab-IRDye800CW (Beva800) is a conjugate of bevacizumab (a humanized antibody targeting human VEGF) and IRDye800CW (a near-infrared fluorescence dye) which binds specifically to VEGF-A. Beva800 provides a potentially highly efficacious approach to imaging specimen and cavity margins during BCS. Herein we present a phase II study that combined Beva800 with the SurgVision Explorer Air camera for intraoperative margin assessment during BCS for EBC.Methods:MARGIN II is a multicenter open-label single arm prospective clinical trial aimed at evaluating Beva800 for assessment of tumor margins in women with EBC scheduled for BCS. The study was a within-patient comparison of positive tumor margin rates using BCS standard of care compared to intraoperative assessment with 4.5 mg Beva800 and fluorescence imaging with the SurgVision Explorer Air camera. Patients undergoing neoadjuvant chemotherapy were excluded. All patients received a single intra-venous bolus injection of 4.5 mg of Beva800 three days before surgery. The fluorescent signal was visualized during surgery using NIR fluorescence imaging (700-1000 nm). This wavelength window typically has very low tissue auto-fluorescence (filtering out background noise) and greater tissue penetration depth due to reduced haemoglobin absorption. Standard of care assessment was defined as visual inspection, palpation and, in cases of pre-operative wire marking, specimen sonography or mammography. Beva800 efficacy was determined as the number of patients in which a pathology-confirmed positive margin was identified by fluorescence guided surgery using Beva800 but not by standard of care BCS. The results per patient were divided into two clusters: results after standard of care BCS and results after fluorescence guided surgery, according to their margin status at pathology. The need for re-operation because of involved margins within 30 days after the first BCS and the safety of 4.5 mg Beva800 was assessed.Results:The recruitment goal of 40 patients in 5 centers has almost been reached and results of the final analysis will be presented at the meeting.Conclusion:Molecular fluorescence-guided surgery using Beva800 has the potential to change the practice of breast conserving surgery by avoiding unnecessary re-operations. This would lead to fewer interventions, a reduced burden on patients through repeat surgery and reduced delay of adjuvant therapies. Citation Format: Hans-Christian Kolberg, Carmen Röhm, Angrit Stachs, Florian Schütz, Jens-Uwe Blohmer, Sarah Wetzig, Steffi Hartmann, Jörg Heil, Markus Hahn. Molecular fluorescence-guided surgery using Beva800 for the assessment of tumor margins during breast conserving surgery of patients with primary breast cancer (MARGIN-II) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS1-21.

Intraoperative free margins assessment of oropharyngeal squamous cell carcinoma with confocal laser endomicroscopy: a pilot study

PurposeThis pilot study aimed to assess the feasibility of intraoperative assessment of safe margins with confocal laser endomicroscopy (CLE) during oropharyngeal squamous cell carcinoma (OPSCC) surgery.MethodsWe included five consecutive patients confirmed OPSCC and planned tumor resection in September and October 2020. Healthy appearing mucosa in the marginal zone, and the tumor margin, were examined with CLE and biopsy during tumor resection. A total of 12,809 CLE frames were correlated with the gold standard of hematoxylin and eosin staining. Three head and neck surgeons and one pathologist were asked to identify carcinoma in a sample of 169 representative images, blinded to the histological results.ResultsHealthy mucosa showed epithelium with uniform size and shape with distinct cytoplasmic membranes and regular vessel architecture. CLE optical biopsy of OPSCC demonstrated a disorganized arrangement of variable cellular morphology. We calculated an accuracy, sensitivity, specificity, PPV, and NPV of 86%, 90%, 79%, 88%, and 82%, respectively, with inter-rater reliability and κ-value of 0.60.ConclusionCLE can be easily integrated into the intraoperative setting, generate real-time, in-vivo microscopic images of the oropharynx for evaluation and demarcation of cancer. It can eventually contribute to a less radical approach by enabling a more precise evaluation of the cancer margin.

Intraoperative frozen section assessment of cavity shave margins in patients undergoing breast conservation surgery

Background: Surgical management of breast cancer has taken a paradigm shift from the early days of the radical Halstedian approach to a newer, relatively conservative approach. Breast conservation surgery (BCS) is the surgery of choice for early breast cancer (EBC). Pathological margin status is the single most important prognostic factor in patients undergoing BCS. Rates of margin positivity after BCS varies between 3- 20%. Multiple techniques have been applied to decrease margin positivity rates in BCS. We evaluated the impact of Intraoperative frozen section assessment of cavity shave margins (IFSA) in patients with EBC undergoing BCS

Combined total internal reflection AF spectral-imaging and Raman spectroscopy for fast assessment of surgical margins during breast cancer surgery.

The standard treatment for breast cancer is surgical removal mainly through breast-conserving surgery (BCS). We developed a new technique based on auto-fluorescence (AF) spectral imaging and Raman spectroscopy for fast intraoperative assessment of excision margins in BCS. A new wide-field AF imaging unit based on total internal reflection (TIR) was combined with a Raman spectroscopy microscope equipped with a 785 nm laser. The wavelength of the AF excitation was optimized to 365 nm in order to maximize the discrimination of adipose tissue. This approach allows for the non-adipose regions of tissue, which are at a higher risk of containing a tumor, to be targeted more efficiently by the Raman spectroscopy measurements. The integrated TIR-AF-Raman was tested on small tissue samples as well as fresh wide local excisions, delivering the analysis of the entire cruciate surface of BCS specimens (5.1 × 7.6 cm2) in less than 45 minutes and also providing information regarding the location of the tumor in the specimen. Full automation of the instrument and selection of a faster translation stage would allow for the measurement of BCS specimens within an intraoperative time scale (20 minutes). This study demonstrates that the TIR-AF Raman microscope represents a feasible step towards the development of a technique for intraoperative assessment of large WLE within intraoperative timescales.

Intraoperative Assessment and Photothermal Ablation of the Tumor Margins Using Gold Nanoparticles.

Surgical resection is commonly used for therapeutic management of different solid tumors and is regarded as a primary standard of care procedure, but precise localization of tumor margins is a major intraoperative challenge. Herein, a generalized method by optimizing gold nanoparticles for intraoperative detection and photothermal ablation of tumor margins is introduced. These nanoparticles are detectable by highly sensitive surface‐enhanced Raman scattering imaging. This non‐invasive technique assists in delineating the two surgically challenged tumors in live mice with orthotopic colon or ovarian tumors. Any remaining residual tumors are also ablated by using post‐surgical adjuvant photothermaltherapy (aPTT), which results in microscale heat generation due to interaction of these nanoparticles with near‐infrared laser. Ablation of these post‐operative residual micro‐tumors prolongs the survival of mice significantly and delays tumor recurrence by 15 days. To validate clinical translatability of this method, the pharmacokinetics, biodistribution, Raman contrast, aPTT efficiency, and toxicity of these nanoparticles are also investigated. The nanoparticles have long blood circulation time (≈24 h), high tumor accumulation (4.87 ± 1.73%ID g−1) and no toxicity. This high‐resolution and sensitive intraoperative approach is versatile and can be potentially used for targeted ablation of residual tumor after resection within different organs.

Feasibility of intraoperative assessment of safe surgical margins during laryngectomy with confocal laser endomicroscopy: A pilot study

ObjectiveThis pilot study aimed to assess the feasibility of intraoperative assessment of safe margins with Confocal Laser Endomicroscopy (CLE) during planned partial or total laryngectomy. MethodsEight patients with confirmed larynx squamous cell carcinoma (SCC) and planned partial or total laryngectomy were included in this study in March 2020. Two head and neck surgeons and one pathologist were asked to classify carcinoma or healthy epithelium in a sample of 94 representative sequences (5.640 images), blinded to the histological results (H&E staining). ResultsHealthy mucosa areas showed epithelium with cells of uniform size and shape with distinct cytoplasmic membranes and regular vessel architecture. CLE optical biopsy of SCC demonstrated a disorganized arrangement of variable cellular morphology. We calculated an accuracy, sensitivity, specificity, PPV, and NPV of 80.1%, 72.3%, 87.9%, 85.7%, and 76.1%, respectively. A distinct transition between healthy appearing tissue and suspicious lesions could also be detected. ConclusionCLE can be easily integrated into the intraoperative setting, generate real-time, in-vivo microscopic images of the larynx for evaluation and demarcation of cancer. If validated in further studies, CLE could eventually contribute to a less radical approach by enabling a more precise evaluation of the cancer margin.

Intraoperative Evaluation of Resection Margins in Breast-Conserving Surgery for In Situ and Invasive Breast Carcinoma.

Background:The challenge of breast-conserving surgery (BCS) is to remove the entire tumour with free margins and avoid secondary excision that may adversely affect the cosmetic outcome. Consequently, intraoperative evaluation of surgical margins is critical. The aims of this study were multiple. First, to analyse our methodology of intraoperative examination of the resection margins and to evaluate radiological and pathological methods in the assessment of the surgical margins. Second, to evaluate the factors associated with positive margins in our patient population.M&m:The data on the resection margin status of 290 patients who underwent BCS for invasive carcinoma or ductal carcinoma in situ (DCIS) between 2009 and 2016 were reviewed.Results:In the cohort of BCS with invasive carcinoma, the negative predictive value was 97.4% for intraoperative assessment by radiography and 81.8% for intraoperative assessment by pathology. The re-operation rate among cases without intraoperative assessment was 23.6% compared to 7.3% among cases with intraoperative assessment (P = .003). Margin status was significantly associated with tumour size, histological subtype (invasive lobular carcinoma), and multifocality. In the population of BCS with DCIS, margin status was significantly associated with preoperative localisation and intraoperative margin assessment (P = .03).Conclusion:There is no statistical difference between pathological and radiological intraoperative assessment. Tumour size, lobular subtype, and multifocality were found to be significantly associated with positive margins in cases with invasive carcinoma, whereas absence of intraoperative margin assessment was significantly associated with positive margins in cases with DCIS. Therefore, intraoperative margin assessment improves the likelihood of complete excision of the lesion.

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.

Laminin - A Prognostic Marker in Oral Squamous Cell Carcinoma

Introduction: Squamous cell carcinoma is one of the most common malignant tumours of the oral cavity and is the tenth most common cause of death worldwide. Because of the high malignant potentially these cases are detected at an advanced stage. Also the recurrence rate is high which invites challenge to the treating surgeon. Laminin, a basement membrane molecule is a reliable marker to predict dif-ferentiation and aggressiveness of the oral squamous cell carcinomas. Methods: The study was conducted in the department of pathology, S. C B Medical College, Cuttack with an aim to predict the tumour aggressiveness and thereby prognosis. A total number of 76 cases were studied using the laminin immunostaining and the results tabulated and interpreted. Results: Majority were well differentiated squamous cell carcinomas, which showed mild to moderate intra cytoplasmic staining of laminin and an intense staining at the tumour host interface, in contrast to an intense intra cytoplasmic staining in poorly differentiated squamous cell carcinoma cases. Those with lymph node metastasis and involved surgical margins also showed intense intra cytoplasmic laminin staining pointing to a higher grade tumour. Conclusion: Laminin immunostaining is definitely superior to the conventional staining procedures for the as-sessment of tumour aggressiveness and differentiation, intra-operative assessment of tumour excision margins and thus access prognosis. Recent researches highlight on Laminin antibodies, which can be used as specific chemotherapeutic agents, to check the process of tumour growth and invasion.

Specimen oriented intraoperative margin assessment in oral cavity and oropharyngeal squamous cell carcinoma

ObjectiveEvaluate the oncologic outcomes and cost analysis of transitioning to a specimen oriented intraoperative margin assessment protocol from a tumour bed sampling protocol in oral cavity (OCSCC) and oropharyngeal squamous cell carcinoma (OPSCC).Study designRetrospective case series and subsequent prospective cohort studySettingTertiary care academic teaching hospitalSubjects and methodsRetrospective case series of all institutional T1-T2 OCSCC or OPSCC treated with primary surgery between January 1st 2009 – December 31st 2014. Kaplan-Meier survival estimates with log rank tests were used to compare patients based on final margin status. Cost analysis was performed for escalation of therapy due to positive final margins. Following introduction of a specimen derived margin protocol, successive prospective cohort study of T1-T4 OCSCC or OPSCC treated with primary surgery from January 1st 2017 – December 31st 2018. Analysis and comparison of both protocols included review of intraoperative margins, final pathology and treatment cost.ResultsAnalysis of our intra-operative tumour bed frozen section protocol revealed 15 of 116 (12.9%) patients had positive final pathology margins, resulting in post-operative escalation of therapy for 14/15 patients in the form of re-resection (7/14), radiation therapy (6/14) and chemoradiotherapy (1/14). One other patient with positive final margins received escalated therapy for additional negative prognostic factors. Recurrence free survival at 3 years was 88.4 and 50.7% for negative and positive final margins respectively (p = 0.048). Implementation of a specimen oriented frozen section protocol resulted in 1 of 111 patients (0.9%) having positive final pathology margins, a statistically significant decrease (p < 0.001). Utilizing our specimen oriented protocol, there was an absolute risk reduction for having a final positive margin of 12.0% and relative risk reduction of 93.0%. Estimated cost avoidance applying the specimen oriented protocol to our previous cohort was $412,052.812017 CAD.ConclusionImplementation of a specimen oriented intraoperative margin protocol provides a statistically significant decrease in final positive margins. This change in protocol leads to decreased patient morbidity by avoiding therapy escalation attributable only to positive margins, and avoids the economic costs of these treatments.Graphical abstract