Positive Surgical Margins in the 10 Most Common Solid Cancers

Therapy-Induced Modulation of the Tumor Microenvironment: New Opportunities for Cancer Therapies

Advances in immunotherapy have achieved remarkable clinical outcomes in tumors with low curability, but their effects are limited, and increasing evidence has implicated tumoral and non-tumoral components of the tumor microenvironment as critical mediators of cancer progression. At the same time, the clinical successes achieved with minimally invasive and optically-guided surgery and image-guided and ablative radiation strategies have been successfully implemented in clinical care. More effective, localized and safer treatments have fueled strong research interest in radioimmunotherapy, which has shown the potential immunomodulatory effects of ionizing radiation. However, increasingly more observations suggest that immunosuppressive changes, metabolic remodeling, and angiogenic responses in the local tumor microenvironment play a central role in tumor recurrence. In this review, we address challenges to identify responders vs. non-responders to the immune checkpoint blockade, discuss recent developments in combinations of immunotherapy and radiotherapy for clinical evaluation, and consider the clinical impact of immunosuppressive changes in the tumor microenvironment in the context of surgery and radiation. Since the therapy-induced modulation of the tumor microenvironment presents a multiplicity of forms, we propose that overcoming microenvironment related resistance can become clinically relevant and represents a novel strategy to optimize treatment immunogenicity and improve patient outcome.

Lugol's Iodine-Enhanced Micro-CT: A Potential 3-D Imaging Method for Detecting Tongue Squamous Cell Carcinoma Specimens in Surgery

Background

A positive surgical margin (PSM) following oral cancer resection results in local recurrence and poor prognosis. Mono-block tumor specimens, especially from the tumor base, are difficult to evaluate. This inaccurate sampling ultimately leads to a false pathological diagnosis. Lugol’s iodine (I₂-IK)-enhanced micro-CT is an emerging method to image tumor specimens. This study explores the feasibility of I₂-IK-enhanced micro-CT to evaluate the surgical margin for tongue squamous cell carcinoma (TSCC) specimens and to further seek optimal staining parameters.

Methods

Rabbit tongue tissues and human TSCC samples were imaged via I₂-IK-enhanced micro-CT. The optimal I₂-IK concentration and staining time were determined before clinical application using tissue shrinkage, micro-CT image quality, and effect on pathological diagnosis as assessment criteria. Next, 6 TSCC specimens were used to verify the process feasibility of surgical margin imaging with the optimal parameters. Finally, the possible reason by which I₂-IK could enhance micro-CT imaging was validated in vitro.

Results

I₂-IK staining influenced specimen shrinkage, micro-CT image quality, and pathological image quality in a concentration- and time-dependent manner. After comprehensively considering these indicators, 3% I₂-IK staining for 48 and 12 h were found to be optimal for rabbit tongue tissues and TSCC samples, respectively. This method could provide a detailed 3-D structure of TSCC samples compared with H&E sections. Moreover, tumor and normal tissues could be differentiated by their glycogen content, which has high affinity with I₂-IK.

Conclusions

I₂-IK-enhanced micro-CT could, thus, indicate the tumor margin and assist pathological sampling in patients with TSCC postoperation.

The feasibility of Miltuximab®-IRDye700DX-mediated photoimmunotherapy of solid tumors

BACKGROUND

Photoimmunotherapy (PIT) is an emerging method of cancer treatment based on the use of a photosensitizer near-infrared dye IRDye700DX (IR700) conjugated to a monoclonal antibody. The antibody selectively delivers IR700 to cancer cells, which can then be killed after photoexcitation. Glypican-1 (GPC-1) is a novel target expressed specifically in malignant tumors. We aimed to investigate whether anti-GPC-1 antibody Miltuximab® (Glytherix Ltd., Sydney, Australia) can be conjugated with IR700 for PIT of solid tumors.

METHODS

The dye IR700 was conjugated with Miltuximab® and characterized by spectrophotometry and flow cytometry. Miltuximab®-IR700-mediated PIT was tested in prostate (DU-145), bladder (C3 and T-24), brain (U-87 and U-251) and ovarian (SKOV-3) cancer cell lines. After 1 h incubation with Miltuximab®-IR700, the cells were washed by PBS and illuminated using a 690-nm light-emitting diode. The viability of the cells was assessed by a CCK-8 viability kit 24 h later.

RESULTS

Miltuximab®-IR700-mediated PIT caused 67.3-92.3% reduction in viability of cells with medium-high GPC-1 expression and did not affect the viability of GPC-1-low cells. Cytotoxicity was attributed to the targeted binding of the conjugate with subsequent photoactivation, as the conjugate or light exposure alone had no effect on the cell viability. Miltuximab®-IR700 did not induce cytotoxicity in cells blocked by unconjugated Miltuximab®.

CONCLUSIONS

PIT with Miltuximab®-IR700 appears to be highly specific and effective against GPC-1-expressing cancer cells, indicating that it holds promise for an effective and safe treatment of early stage solid tumors or as adjuvant therapy following surgical resection. These findings necessitate further investigation of PIT with Miltuximab®-IR700 in other GPC-1-expressing cancer cell lines in vitro and in vivo in xenograft tumor models.

AND-gate contrast agents for enhanced fluorescence-guided surgery

The surgical resection of tumours requires the precise location and definition of the margins between lesions and normal tissue. However, this is made difficult by irregular margin borders. Although molecularly targeted optical contrast agents can be used to define tumour margins during surgery in real time, the selectivity of the contrast agents is often limited by the target being expressed in both healthy and tumour tissues. Here, we show that AND-gate optical imaging probes requiring the processing of two substrates by multiple tumour-specific enzymes produce a fluorescent signal with significantly improved specificity and sensitivity to tumour tissue. We evaluated the performance of the probes in mouse models of mammary tumours and of metastatic lung cancer, and during fluorescence-guided robotic surgery. Imaging probes relying on multivariate activation to selectively target complex patterns of enzymatic activity should be useful in disease detection, treatment and monitoring.

The Delivery Materials with Chemotherapy Drugs for Treatment of the Positive Margin in Solid Tumors

The positive surgical margins in solid tumors has been a disturbing issue for clinicians. Chemotherapy is an important method to deal with the positive margin. However, systemic chemotherapy is required for long-term administration and has great side effects on health, which cause great pain to the patients. Local administration of slow-release materials provides an opportunity to improve the situation. In this study, we utilized electrospinning technology to create the drug sustained-release materials with nanofibrous structure, which were made from polylactic acid and a certain proportion of chemotherapy drugs (gemcitabine and cisplatin). In vitro release behavior of the drug sustained-release materials were explored by the high-performance liquid chromatography. The antitumor efficacy of the drug sustained-release materials was preliminarily verified in prostate cancer and breast cancer in vitro. Through animal models of breast cancer, the drug sustained-release materials in the treatment of the positive margin has been well documented in vivo, and we also found that the drug sustained-release materials could definitely reduce the liver damage and myelosuppression compared with systemic chemotherapy. In summary, the experimental results showed that the local administration of the drug sustained-release materials could effectively inhibit the growth of the positive incision margins and definitely reduce the partial side effects associated with systemic chemotherapy.

Differential mobility spectrometry imaging for pathological applications

Pathologic examination of clinical tissue samples is time consuming and often does not involve the comprehensive analysis of the whole specimen. Automated tissue analysis systems have potential to make the workflow of a pathologist more efficient and to support in clinical decision-making. So far, these systems have been based on application of mass spectrometry imaging (MSI). MSI provides high fidelity and the results in tissue identification are promising. However, the high cost and need for maintenance limit the adoption of MSI in the clinical setting. Thus, there is a need for new innovations in the field of pathological tissue imaging. In this study, we show that differential ion mobility spectrometry (DMS) is a viable option in tissue imaging. We demonstrate that a DMS-driven solution performs with up to 92% accuracy in differentiating between two grossly distinct animal tissues. In addition, our model is able to classify the correct tissue with 81% accuracy in an eight-class setting. The DMS-based system is a significant innovation in a field dominated by mass-spectrometry-based solutions. By developing the presented platform further, DMS technology could be a cost-effective and helpful tool for automated pathological analysis.

Oral Biopsy Techniques

Squamous cell carcinoma makes up 90% of cases of oral cancer. However, a myriad of premalignant, inflammatory, and immune-based conditions can manifest as oral mucosal lesions. Biopsy of these lesions shares many of the principles of cutaneous lesions. Biopsy of oral mucosal lesions is a procedure that is safely performed in most cases in the outpatient ambulatory setting using local anesthesia. Special considerations should be taken depending on the presumed diagnosis based on physical examination. Its clinical relevance depends on a sound clinicopathologic assessment of the patient's condition. This article reviews specific considerations for biopsy of oral mucosal lesions.

Impact of axillary node-positivity and surgical resection margins on survival of women treated for breast cancer in Ibadan, Nigeria

Introduction

Oncologic surgical extirpation, the mainstay of loco-regional disease control in breast cancer, is aimed at achieving negative margins and lymph node clearance. Even though axillary lymph nodal metastasis is a critical index of prognostication, establishing the impact of lymph node ratio (LNR) and adequate surgical margins on disease-specific survivorship would be key to achieving longer survival. This study examines the prognostic role of pN (lymph nodes positive for malignancy), LNR and resection margin on breast cancer survival in a tertiary hospital in Ibadan, Nigeria.

Methods

We conducted a longitudinal cohort study of 225 patients with breast carcinoma, documented clinico-pathologic parameters and 5-year follow up outcomes - distant metastasis and survival. Chi-square test and logistic regression analysis were used to evaluate the interaction of resection margin and proportion of metastatic lymph nodes with patients' survival. The receiver operating characteristic curve was plotted to determine the proportion of metastatic lymph nodes which predicted survival. The survival analysis was done using Kaplan-Meier method.

Results

Sixty (26.7%) patients of the patients had positive resection margins, with the most common immuno-histochemical type being Lumina A. 110 (49%) patients had more than 10 axillary lymph nodes harvested. The mean age was 48.6 ± 11.8 years. Tumour size (p = 0.018), histological type (p = 0.015), grade (p = 0.006), resection margin (p = 0.023), number of harvested nodes (p < 0.01), number of metastatic nodes (p < 0.001) and loco-regional recurrence (p < 0.01) are associated with survival. The overall 5-year survival was 65.3%.

Conclusion

Unfavourable survival outcomes following breast cancer treatment is multifactorial, including the challenges faced in the multimodal treatment protocol received by our patients.

Nanoparticle Formulation of Indocyanine Green Improves Image-Guided Surgery in a Murine Model of Breast Cancer

PURPOSE

Negative surgical margins (NSMs) have favorable prognostic implications in breast tumor resection surgery. Fluorescence image-guided surgery (FIGS) has the ability to delineate surgical margins in real time, potentially improving the completeness of tumor resection. We have recently developed indocyanine green (ICG)-loaded self-assembled hyaluronic acid (HA) nanoparticles (NanoICG) for solid tumor imaging, which were shown to enhance intraoperative contrast.

PROCEDURES

This study sought to assess the efficacy of NanoICG on completeness of breast tumor resection and post-surgical survival. BALB/c mice bearing iRFP+/luciferase+ 4T1 syngeneic breast tumors were administered NanoICG or ICG, underwent FIGS, and were compared to bright light surgery (BLS) and sham controls.

RESULTS

NanoICG increased the number of complete resections and improved tumor-free survival. This was a product of improved intraoperative contrast enhancement and the identification of a greater number of small, occult lesions than ICG and BLS. Additionally, NanoICG identified chest wall invasion and predicted recurrence in a model of late-stage breast cancer.

CONCLUSIONS

NanoICG is an efficacious intraoperative contrast agent and could potentially improve surgical outcomes in breast cancer.

Identification of diagnostic metabolic signatures in clear cell renal cell carcinoma using mass spectrometry imaging

Clear cell renal cell carcinoma (ccRCC) is the most common and lethal subtype of kidney cancer. Intraoperative frozen section (IFS) analysis is used to confirm the diagnosis during partial nephrectomy. However, surgical margin evaluation using IFS analysis is time consuming and unreliable, leading to relatively low utilization. In our study, we demonstrated the use of desorption electrospray ionization mass spectrometry imaging (DESI-MSI) as a molecular diagnostic and prognostic tool for ccRCC. DESI-MSI was conducted on fresh-frozen 23 normal tumor paired nephrectomy specimens of ccRCC. An independent validation cohort of 17 normal tumor pairs was analyzed. DESI-MSI provides two-dimensional molecular images of tissues with mass spectra representing small metabolites, fatty acids and lipids. These tissues were subjected to histopathologic evaluation. A set of metabolites that distinguish ccRCC from normal kidney were identified by performing least absolute shrinkage and selection operator (Lasso) and log-ratio Lasso analysis. Lasso analysis with leave-one-patient-out cross-validation selected 57 peaks from over 27,000 metabolic features across 37,608 pixels obtained using DESI-MSI of ccRCC and normal tissues. Baseline Lasso of metabolites predicted the class of each tissue to be normal or cancerous tissue with an accuracy of 94 and 76%, respectively. Combining the baseline Lasso with the ratio of glucose to arachidonic acid could potentially reduce scan time and improve accuracy to identify normal (82%) and ccRCC (88%) tissue. DESI-MSI allows rapid detection of metabolites associated with normal and ccRCC with high accuracy. As this technology advances, it could be used for rapid intraoperative assessment of surgical margin status.

Predictive Factors of Positive Circumferential and Longitudinal Margins in Early T3 Colorectal Cancer Resection

Background

Malignant involvement of circumferential resection margin (CRM) and longitudinal resection margin (LRM) after surgical resection of colorectal cancer (CRC) are associated with higher rates of recurrence and development of distant metastasis. This can influence the overall patient's prognosis. The aim of the current study was to identify pathological factors as predictors for the involvement of resection margins in early T3 CRC. Patients and Methods. Fifty patients radiologically diagnosed to have cT3a/b (CRC) were included in the study. After resection, the pathological examination was performed to identify patients with positive CRM and/or LRM. Relations between the different pathological parameters and the CMR and LRM involvements were assessed.

Results

Positive CRM was present in 17 cases (34%), while positive LRM was found in 6 cases (12%). The involvement of both margins was significantly associated with rectal tumors and tumors with infiltrative gross appearance, grade III, deeper invasion, and positive lymph node metastases. Also, there was a significant association between both margins' positivity and other pathological parameters as signet ring carcinoma, tumor budding, perineural and vascular invasion, high microvessel density (MVD), and sinusoidal vascular pattern, while the presence of necrosis and infiltrative advancing tumor front was significantly associated with CRM involvement only. The depth of tumor invasion and signet ring carcinoma were identified as independent predictor factors for positive CRM and LRM, respectively.

Conclusion

Preoperative identification of these pathological parameters can be a guide to tailor the management plan accordingly.

Mid-Infrared Imaging Is Able to Characterize and Separate Cancer Cell Lines

Malignancies are still responsible for a large share of lethalities. Macroscopical evaluation of the surgical resection margins is uncertain. Big data based imaging approaches have emerged in the recent decade (mass spectrometry, two-photon microscopy, infrared and Raman spectroscopy). Indocianine green labelled MS is the most common approach, however, label free mid-infrared imaging is more promising for future practical application. We aimed to identify and separate different transformed (A-375, HT-29) and non-transformed (CCD986SK) cell lines by a label-free infrared spectroscopy method. Our approach applied a novel set-up for label-free mid-infrared range classification method. Transflection spectroscopy was used on aluminium coated glass slides. Both whole range spectra (4000-648 cm^-1) and hypersensitive fingerprint regions (1800-648 cm^-1) were tested on the imaged areas of cell lines fixed in ethanol. Non-cell spectra were possible to be excluded based on mean transmission values being above 90%. Feasibility of a mean transmission based spectra filtering method with principal component analysis and linear discriminant analysis was shown to separate cell lines representing different tissue types. Fingerprint region resulted the best separation of cell lines spectra with accuracy of 99.84% at 70-75 mean transmittance range. Our approach in vitro was able to separate unique cell lines representing different tissues of origin. Proper data handling and spectra processing are key steps to achieve the adaptation of this dye-free technique for intraoperative surgery. Further studies are urgently needed to test this novel, marker-free approach.

EGFR and αvβ6 as Promising Targets for Molecular Imaging of Cutaneous and Mucosal Squamous Cell Carcinoma of the Head and Neck Region

R0 resection is paramount in cutaneous squamous cell carcinoma (CSCC) and head and neck squamous cell carcinoma (HNSCC). However, in the setting of recurrence, immunocompromised patients, or non-keratinizing squamous cell carcinoma (SCC) with a spindle growth pattern, tumor borders are difficult, if not impossible, to determine. Fluorescence-guided surgery (FGS) aids in this differentiation. Potential targets for FGS of CSCC and HNSCC were evaluated. Most sections stained intensely for αvβ6 and epidermal growth factor receptor (EGFR) on tumor cells. Normal epithelium stained less for αvβ6 than for EGFR. In addition, soft tissue and stroma stained negative for both, allowing for clear discrimination of the soft tissue margin. Tumor cells weakly expressed urokinase plasminogen activator receptor (uPAR) while expression on stromal cells was moderate. Normal epithelium rarely expressed uPAR, resulting in clear discrimination of superficial margins. Tumors did not consistently express integrin β3, carcinoembryonic antigen, epithelial cell adhesion molecule, or vascular endothelial growth factor A. In conclusion, αvβ6 and EGFR allowed for precise discrimination of SSC at the surgically problematic soft tissue margins. Superficial margins are ideally distinguished with uPAR. In the future, FGS in the surgically challenging setting of cutaneous and mucosal SCC could benefit from a tailor-made approach, with EGFR and αvβ6 as targets.

Genomics and precision surgery for head and neck squamous cell carcinoma

The identification of the biological determinants that shape the response of tumors to medical therapies offers perspectives for better patient stratification and therapeutic targeting. Here, we discuss how genomics could help to improve the surgical treatment of head and neck squamous cell carcinoma (HNSCC). We examine the potential use of genomic analyses for: i) refining and standardizing the indications for surgery, ii) the choice of surgical procedure, and iii) the follow-up of patients with resected tumors. We highlight the studies that used genomics to explore the contribution of tumor biology to the outcome of surgery. We discuss the important developments that are challenging current surgical practice in HNSCC, such as neoadjuvant immunotherapy and the analysis of circulating DNA. Genomic analyses provide practical tools that could help improve the pathological diagnosis and staging of HNSCC, and increase the appreciation of the importance of tumor biology in the outcome of surgery. Identification of biomarkers will likely contribute to a move toward precision surgery of HNSCC, i.e. the personalization of surgical practice based on tumor biology.

Terahertz Imaging and Characterization Protocol for Freshly Excised Breast Cancer Tumors

This manuscript presents a protocol to handle, characterize, and image freshly excised human breast tumors using pulsed terahertz imaging and spectroscopy techniques. The protocol involves terahertz transmission mode at normal incidence and terahertz reflection mode at an oblique angle of 30°. The collected experimental data represent time domain pulses of the electric field. The terahertz electric field signal transmitted through a fixed point on the excised tissue is processed, through an analytical model, to extract the refractive index and absorption coefficient of the tissue. Utilizing a stepper motor scanner, the terahertz emitted pulse is reflected from each pixel on the tumor providing a planar image of different tissue regions. The image can be presented in time or frequency domain. Furthermore, the extracted data of the refractive index and absorption coefficient at each pixel are utilized to provide a tomographic terahertz image of the tumor. The protocol demonstrates clear differentiation between cancerous and healthy tissues. On the other hand, not adhering to the protocol can result in noisy or inaccurate images due to the presence of air bubbles and fluid remains on the tumor surface. The protocol provides a method for surgical margins assessment of breast tumors.

Image-guided tumor surgery: The emerging role of nanotechnology

Surgical resection is a mainstay treatment for solid tumors. Yet, methods to distinguish malignant from healthy tissue are primarily limited to tactile and visual cues as well as the surgeon's experience. As a result, there is a possibility that a positive surgical margin (PSM) or the presence of residual tumor left behind after resection may occur. It is well-documented that PSMs can negatively impact treatment outcomes and survival, as well as pose an economic burden. Therefore, surgical tumor imaging techniques have emerged as a promising method to decrease PSM rates. Nanoparticles (NPs) have unique characteristics to serve as optical contrast agents during image-guided surgery (IGS). Recently, there has been tremendous growth in the volume and types of NPs used for IGS, including clinical trials. Herein, we describe the most recent contributions of nanotechnology for surgical tumor identification. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Implantable Materials and Surgical Technologies > Nanoscale Tools and Techniques in Surgery Diagnostic Tools > in vivo Nanodiagnostics and Imaging.

Fluorescence-guided imaging for resection margin evaluation in head and neck cancer patients using cetuximab-800CW: A quantitative dose-escalation study

Tumor-positive resection margins are present in up to 23% of head and neck cancer (HNC) surgeries, as intraoperative techniques for real-time evaluation of the resection margins are lacking. In this study, we investigated the safety and potential clinical value of fluorescence-guided imaging (FGI) for resection margin evaluation in HNC patients. We determined the optimal cetuximab-800CW dose by quantification of intrinsic fluorescence values using multi-diameter single-fiber reflectance, single-fiber fluorescence (MDSFR/SFF) spectroscopy.

Methods: Five cohorts of three HNC patients received cetuximab-800CW systemically: three single dose cohorts (10, 25, 50 mg) and two cohorts pre-dosed with 75 mg unlabeled cetuximab (15 or 25 mg). Fluorescence visualization and MDSFR/SFF spectroscopy quantification was performed and were correlated to histopathology.

Results: There were no study-related adverse events higher than Common Terminology Criteria for Adverse Events grade-II. Quantification of intrinsic fluorescence values showed a dose-dependent increase in background fluorescence in the single dose cohorts (p<0.001, p<0.001), which remained consistently low in the pre-dosed cohorts (p=0.6808). Resection margin status was evaluated with a sensitivity of 100% (4/4 tumor-positive margins) and specificity of 91% (10/11 tumor-negative margins).

Conclusion: A pre-dose of 75 mg unlabeled cetuximab followed by 15 mg cetuximab-800CW was considered the optimal dose based on safety, fluorescence visualization and quantification of intrinsic fluorescence values. We were able to use a lower dose cetuximab-800CW than previously described, while remaining a high sensitivity for tumor detection due to application of equipment optimized for IRDye800CW detection, which was validated by quantification of intrinsic fluorescence values.

Estimated Costs Associated With Radiation Therapy for Positive Surgical Margins During Radical Prostatectomy

IMPORTANCE

Prostate cancer is the most common malignant neoplasm among men and is the one with the highest positive surgical margin (PSM) rate. This high rate is due to the difficulty in balancing the risk of extraprostatic disease and excising periprostatic structures, which ultimately affects patients' quality of life. In the case of a PSM, the appropriateness of adjuvant radiation therapy (aRT) should be discussed. The financial burden of PSMs on health systems has not been investigated.

OBJECTIVE

To estimate the financial costs associated with a PSM during radical prostatectomy on the basis of the odds of undergoing aRT.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used data on men with prostate cancer from the US National Cancer Database (January 1, 2010, through December 31, 2015). Data were requested in March 2019, accessed in April 2019, and analyzed in August 2019.

EXPOSURE

Treatment with radical prostatectomy followed by aRT, if indicated.

MAIN OUTCOMES AND MEASURES

The attributable risk fraction of PSMs on undergoing aRT was estimated from a logistic regression with aRT administration as the outcome. The analysis was adjusted for patients' socioeconomic and demographic characteristics and tumor characteristics. The aRT cost for the year 2019 was calculated using the Medicare Physician Fee Schedule and the Hospital Outpatient Prospective Payment System. The fraction of this cost attributable to a PSM was estimated according to its attributable risk fraction.

RESULTS

In total, 230 175 men were identified (median [interquartile range] age at diagnosis, 62.0 [56.0-67.0] years). Overall, 22.8% of the patients had a PSM. Patients with PSMs were more likely than those without PSMs to be older (median [interquartile range] age, 62.0 [56.0-66.0] years vs 62.0 [57.0-67.0] years) and nonwhite (9320 patients [17.8%] vs 29 872 patients [16.8%]), to have higher comorbidity scores (1604 patients [3.1%] vs 4884 patients [2.7%] with a Charlson-Deyo Comorbidity Index score ≥2) and worse tumor characteristics (category T3 and T4 disease, 26 394 patients [50.3%] vs 36 040 patients [20.3%]), and to have lower socioeconomic indicators (median annual income <$30 000, 5708 patients [10.9%] vs 17 874 patients [10.1%]; proportion of individuals without a high school degree in the area ≥29%, 6925 patients [13.2%] vs 22 648 patients [12.7%]). In addition, PSMs were documented more frequently at nonacademic institutions than academic ones (31 702 patients [60.5%] vs 20 714 patients [39.5%]). A total of 11 585 patients (5.0%) underwent aRT, and 7698 of them (3.3%) had a PSM at the final pathology examination. When controlling for patients' socioeconomic and demographic characteristics and tumor characteristics, men with PSMs were more likely than those with negative margins to undergo aRT, with an odds ratio of 3.79 (95% CI, 3.63-3.96; P < .001). The attributable risk fraction of the presence of a PSM on aRT was 44% (95% CI, 42%-45%). The attributable cost of a PSM was calculated as $17 356 (95% CI, $16 567-$17 751). Assuming 60 000 prostatectomies in 2019 and similar trends of PSM and aRT, the overall health burden attributable to PSMs was calculated to be $52 068 000 (95% CI, $49 701 000-$53 253 000).

CONCLUSIONS AND RELEVANCE

The estimated aRT cost attributable to the presence of a PSM was $17 356, resulting in $52 068 000 in spending on aRT in 2019. Strategies to reduce PSMs could be associated with a reduction in the overall health costs of surgically treated PCa.

The Impact of Prostate Cancer Upgrading and Upstaging on Biochemical Recurrence and Cancer-Specific Survival

Background and Objectives: Significant numbers of prostate cancer (PCa) patients experience tumour upgrading and upstaging between prostate biopsy and radical prostatectomy (RP) specimens. The aim of our study was to investigate the role of grade and stage increase on surgical and oncological outcomes. Materials and Methods: Upgrading and upstaging rates were analysed in 676 treatment-naïve PCa patients who underwent RP with subsequent follow-up. Positive surgical margin (PSM), biochemical recurrence (BCR), metastasis-free survival (MFS), overall (OS) and cancer specific survival (CSS) were analysed according to upgrading and upstaging. Results: Upgrading was observed in 29% and upstaging in 22% of PCa patients. Patients undergoing upgrading or upstaging were 1.5 times more likely to have a PSM on RP pathology. Both upgrading and upstaging were associated with increased risk for BCR: 1.8 and 2.1 times, respectively. Mean time to BCR after RP was 2.1 years in upgraded cases and 2.7 years in patients with no upgrading (p < 0.001), while mean time to BCR was 1.9 years in upstaged and 2.8 years in non-upstaged cases (p < 0.001). Grade and stage increase after RP were associated with inferior MFS rates and ten-year CSS: 89% vs. 98% for upgrading (p = 0.039) and 87% vs. 98% for upstaging (p = 0.008). Conclusions: Currently used risk stratification models are associated with substantial misdiagnosis. Pathological upgrading and upstaging have been associated with inferior surgical results, substantial higher risk of BCR and inferior rates of important oncological outcomes, which should be considered when counselling PCa patients at the time of diagnosis or after definitive therapy.

Visible near infrared reflectance molecular chemical imaging of human ex vivo carcinomas and murine in vivo carcinomas

SIGNIFICANCE

A key risk faced by oncological surgeons continues to be complete removal of tumor. Currently, there is no intraoperative imaging device to detect kidney tumors during excision.

AIM

We are evaluating molecular chemical imaging (MCI) as a technology for real-time tumor detection and margin assessment during tumor removal surgeries.

APPROACH

In exploratory studies, we evaluate visible near infrared (Vis-NIR) MCI for differentiating tumor from adjacent tissue in ex vivo human kidney specimens, and in anaesthetized mice with breast or lung tumor xenografts. Differentiation of tumor from nontumor tissues is made possible with diffuse reflectance spectroscopic signatures and hyperspectral imaging technology. Tumor detection is achieved by score image generation to localize the tumor, followed by application of computer vision algorithms to define tumor border.

RESULTS

Performance of a partial least squares discriminant analysis (PLS-DA) model for kidney tumor in a 22-patient study is 0.96 for area under the receiver operating characteristic curve. A PLS-DA model for in vivo breast and lung tumor xenografts performs with 100% sensitivity, 83% specificity, and 89% accuracy.

CONCLUSION

Detection of cancer in surgically resected human kidney tissues is demonstrated ex vivo with Vis-NIR MCI, and in vivo on mice with breast or lung xenografts.

Anti-carcinoembryonic antigen-related cell adhesion molecule antibody for fluorescence visualization of primary colon cancer and metastases in patient-derived orthotopic xenograft mouse models

Background: Monoclonal antibody (mAb) 6G5j is a novel anti-CEACAM monoclonal antibody. Our aim was to investigate mAb 6G5j binding characteristics and to validate fluorescence targeting of colorectal tumors and metastases in patient derived orthotopic xenograft (PDOX) models with fluorescently labeled 6G5j.

Materials/Methods: The MAb 6G5j binding profile was analyzed with ELISA, Western blot and immunohistochemistry. MAb 6G5j was conjugated to near-infrared dye IR800CW (LI-COR). Western blotting was performed with various colon cancer cell lysates to determine CEACAM expression. Nude mice received orthotopic implantation of patient-derived primary colon cancer and patient-derived colon cancer metastases. Mice were administered varying doses of 6G5j-IR800CW via tail vein injection and imaged 24 and 48 hours later.

Results: MAb 6G5j bound to human CEACAM1, 3, 5, 6 and 8. Western blotting demonstrated varied expression of CEACAMs in 15 of 16 colon cancer lysates. Dose and time-response imaging demonstrated optimal imaging 48 hours after administration of 50 μg 6G5j-IR800CW (Tumor-to-liver ratio (TLR) 3.17, SEM ± 0.45). Primary cancers and multiple metastases were fluorescently visualized.

Conclusions: Anti-CEACAM antibody 6G5j binds multiple CEACAMs which may lead to improved detection of tumor margins for tumors and metastases that have variable expression of CEA and other CEACAMs. 6G5j mAb may be useful for colon cancer detection for pre-surgical diagnosis and fluorescence-guided surgery.

Extent of Peritoneal Resection for Peritoneal Metastases: Looking Beyond a Complete Cytoreduction

Completeness of cytoreduction is one of the most important prognostic factors impacting outcomes of cytoreductive surgery (CRS). To what extent the surrounding normal peritoneum needs to be removed is not known. We hypothesized that the extent of peritoneal resection should be different for different tumors and performed this study to find evidence to support this rationale. To determine the extent of resection of surrounding tissue for any tumor, the mechanisms of tumor development and spread, tumor morphology, the possibility of finding disease in the surrounding normal tissue, and the pattern of lymph node metastases should be known. Surgical resections also depend on patterns of recurrence and the impact of varying extent of resection on survival. We performed a review of literature pertaining to pathways and patterns of peritoneal cancer spread to determine the scientific basis for the extent of peritonectomy. We also reviewed studies comparing less and more extensive peritoneal resection. There is no consensus on the extent of lymphadenectomy required for most PM. Based on this review, we provide recommendations for the extent of peritoneal resection and the extent of lymph node dissection that should be performed for some common peritoneal tumors and identify areas that require further research. We propose that a systematic method of synoptic reporting of pathological specimens of CRS should be developed to capture information regarding the disease distribution within the peritoneal cavity and morphology of PM from different tumors. This can in future be used to establish standard guidelines for such resections.

Margin Positivity in Resectable Esophageal Cancer: Are there Modifiable Risk Factors?

BACKGROUND

Patients with esophageal cancer have poor overall survival, with positive resection margins worsening survival. Margin positivity rates are used as quality measures in other malignancies, but modifiable risk factors are necessary to develop actionable targets for improvement. Our objectives were to (1) evaluate trends in esophageal cancer margin positivity, and (2) identify modifiable patient/hospital factors associated with margin positivity.

METHODS

Patients who underwent esophagectomy from 2004 to 2015 were identified from the National Cancer Database. Trends in margin positivity by time and hospital volume were evaluated using Cochrane-Armitage tests. Associations between patient/hospital factors and margin positivity were assessed by multivariable logistic regression.

RESULTS

Among 29,706 patients who underwent esophagectomy for cancer, 9.37% had positive margins. Margin positivity rates decreased over time (10.62% in 2004 to 8.61% in 2015; p < 0.001). Older patients (≥ 75 years) were more likely to have positive margins [odds ratio (OR) 2.04, 95% confidence interval (CI) 1.42-2.92], as were patients with a Charlson-Deyo Index ≥ 3 (OR 1.84, 95% CI 1.08-3.12). Patients who received neoadjuvant therapy were less likely to have positive margins (OR 0.37, 95% CI 0.29-0.47), while laparoscopic surgical approach was associated with increased margin positivity (OR 1.70, 95% CI 1.40-2.06). As the hospital annual esophagectomy volume increased, margin positivity rates decreased (7.76% in the fourth quartile vs. 11.39% in the first quartile; OR 0.70, 95% CI 0.49-0.99).

CONCLUSIONS

Use of neoadjuvant therapy, surgical approach, and hospital volume are modifiable risk factors for margin positivity in esophageal cancer. These factors should be considered in treatment planning, and margin positivity rates could be considered as a quality measure in esophageal cancer.

Intraoperative Molecular Imaging for ex vivo Assessment of Peripheral Margins in Oral Squamous Cell Carcinoma

Objective: Complete surgical resection is the standard of care for treatment of oral cancer although the positive margin rate remains 15–30%. Tissue sampling from the resected specimen and from the wound bed for frozen section analysis (FSA) remains the mainstay for intraoperative margin assessment but is subject to sampling error and can require the processing of multiple samples. We sought to understand if an ex vivo imaging strategy using a tumor-targeted fluorescently labeled antibody could accurately identify the closest peripheral margin on the mucosal surface of resected tumor specimen, so that this “sentinel margin” could be used to guide pathological sampling.

Materials and Methods: Twenty-nine patients with oral squamous cell carcinoma scheduled for surgical resection were consented for the study and received systemic administration of a tumor-targeted fluorescently labeled antibody (Panitumumab IRDye800CW). After surgical resection, the tumor specimen was imaged using a closed-field fluorescent imaging device. Relevant pathological data was available for five patients on retrospective review. For each of these five patients, two regions of highest fluorescence intensity at the peripheral margin and one region of lowest fluorescence intensity were identified, and results were correlated with histology to determine if the region of highest fluorescence intensity along the mucosal margin (i.e., the sentinel margin) was truly the closest margin.

Results: Imaging acquisition of the mucosal surface of the specimen immediately after surgery took 30 s. In all of the specimens, the region of highest fluorescence at the specimen edge had a significantly smaller margin distance than other sampled regions. The average margin distance at the closest, “sentinel,” margin was 3.2 mm compared to a margin distance of 8.0 mm at other regions (p < 0.0001).

Conclusions: This proof-of-concept study suggests that, when combined with routine FSA, ex vivo fluorescent specimen imaging can be used to identify the closest surgical margin on the specimen. This approach may reduce sampling error of intraoperative evaluation, which should ultimately improve the ability of the surgeon to identify the sentinel margin. This rapid sentinel margin identification improves the surgeon's orientation to areas most likely to be positive in the surgical wound bed and may expedite pathology workflow.

A proof-of-concept methodology to validate the in situ visualization of residual disease using cancer-targeted molecular agents in fluorescence-guided surgery

Introduction

The clinical need for improved intraoperative tumor visualization has led to the development of targeted contrast agents for fluorescence-guided surgery (FGS). A key characteristic of these agents is their high tumor specificity, which could enable detection of residual lesions that would likely be missed by visual inspection. Here, we examine the utility of a promising somatostatin receptor subtype-2 (SSTR2)-targeted fluorescent agent for detecting residual disease in mouse xenografts using FGS and post-operative histopathological validation.

Methods

Mice (n=2) implanted with SSTR2 overexpressing tumors were injected with 2 nmol of the dual-labeled somatostatin analog, ⁶⁷Ga-MMC(IR800)-TOC, and tumors were resected 48 h post-injection using traditional white light reflectance and palpation. Tumors underwent gamma counting and histopathology analysis. The wide-field FGS imaging platform (OnLume) was used to evaluate residual disease in situ under ambient light representative of an operating room.

Results

The tumor was resected with grossly negative margins using conventional inspection and palpation; however, additional in situ residual disease was found in the tumor cavity using FGS imaging. In situ fluorescent tumor contrast-to-noise ratios (CNRs) were 3.0 and 5.2. Agent accumulation was 7.72 and 8.20 %ID/g in tumors and 0.27 and 0.20 %ID/g in muscle. Fluorescence pixel values and gamma counts were highly correlated (r = 0.95, P < 0.048). H&E and IHC staining confirmed cancer positivity and SSTR2-overexpression, respectively.

Conclusion

Our findings demonstrate that the use of clinically relevant fluorescence imaging instrumentation enhances the evaluation of promising FGS agents for in situ visualization of residual disease.

Near-infrared imaging and optical coherence tomography for intraoperative visualization of tumors

Surgical excision is the foundation of treatment for early-stage solid tumors in man and companion animals. Complete excision with appropriate margins of surrounding tumor-free tissue is crucial to survival. Intraoperative imaging allows real-time visualization of tumors, assessment of surgical margins, and, potentially, lymph nodes and satellite metastatic lesions, allowing surgeons to perform complete tumor resections while sparing surrounding vital anatomic structures. This Review will focus on the use of near-infrared imaging and optical coherence tomography for intraoperative tumor visualization.

Totally robotic vs hybrid abdominoperineal resection: A retrospective multicenter analysis

INTRODUCTION

Laparoscopic abdominoperineal resection (APR) for low rectal cancers is technically demanding. Robotic assistance may be of help and can be hybrid (HAPR) or totally robotic (RAPR). The present study describes outcomes of robotic APR and compares both approaches.

MATERIAL AND METHODS

A multicentric retrospective analysis of rectal cancer patients undergoing either HAPR or RAPR was conducted. Patients' demographics, surgeons' experience, oncologic results, and intraoperative and postoperative outcomes were collected.

RESULTS

One hundred twenty-five patients were included, 48 in HAPR group and 77 in RAPR group. Demographics and comorbidities were comparable. Operative time was reduced in RAPR group (266.9 ± 107.8 min vs 318.9 ± 75.1 min, P = .001). RAPR patients were discharged home more frequently (91.18% vs 66.67%, P = .001), and experienced fewer parastomal hernias (3.71% vs 9.86%, P = .001).

CONCLUSION

RAPR is safe and feasible with appropriate oncologic outcomes. Totally robotic approach reduces operative time and may improve functional outcomes.

Contemporary Approach to Locally Advanced Oral Cavity Squamous Cell Carcinoma

PURPOSE OF REVIEW

Surgical management of locally advanced oral cavity squamous cell carcinomas (OCSCC) has long been recognized as a primary treatment modality. Technological advances have led to significant improvements in our surgical approach, from improvement in the visualization of tumors to more efficient and precise reconstruction. Here, we review the latest technological advances in surgical extirpation and reconstruction of locally advanced OCSCCs.

RECENT FINDINGS

The focus of technological innovation in surgical extirpation has been on improving visualization, with the use of intraoperative ultrasound for margin delineation, intraoperative navigation, narrow-band imaging, and the use of fluorescence. Though early, these are promising steps to ensuring complete resection of the cancer. Advances in reconstruction have been centered on the incorporation of computer assisted design, manufacturing, and virtual surgical planning, allowing for more complex three-dimensional defects to be expeditiously reconstructed. As these technologies are still under development, their impact on oncologic outcomes are not yet robustly defined; however, as technology continues to advance and become more widely available, new technologies will undoubtedly become integrated into enhancing surgical precision and planning.

A 25 micron-thin microscope for imaging upconverting nanoparticles with NIR-I and NIR-II illumination

Rationale: Intraoperative visualization in small surgical cavities and hard-to-access areas are essential requirements for modern, minimally invasive surgeries and demand significant miniaturization. However, current optical imagers require multiple hard-to-miniaturize components including lenses, filters and optical fibers. These components restrict both the form-factor and maneuverability of these imagers, and imagers largely remain stand-alone devices with centimeter-scale dimensions. Methods: We have engineered INSITE (Immunotargeted Nanoparticle Single-Chip Imaging Technology), which integrates the unique optical properties of lanthanide-based alloyed upconverting nanoparticles (aUCNPs) with the time-resolved imaging of a 25-micron thin CMOS-based (complementary metal oxide semiconductor) imager. We have synthesized core/shell aUCNPs of different compositions and imaged their visible emission with INSITE under either NIR-I and NIR-II photoexcitation. We characterized aUCNP imaging with INSITE across both varying aUCNP composition and 980 nm and 1550 nm excitation wavelengths. To demonstrate clinical experimental validity, we also conducted an intratumoral injection into LNCaP prostate tumors in a male nude mouse that was subsequently excised and imaged with INSITE. Results: Under the low illumination fluences compatible with live animal imaging, we measure aUCNP radiative lifetimes of 600 μs - 1.3 ms, which provides strong signal for time-resolved INSITE imaging. Core/shell NaEr0.6Yb0.4F4 aUCNPs show the highest INSITE signal when illuminated at either 980 nm or 1550 nm, with signal from NIR-I excitation about an order of magnitude brighter than from NIR-II excitation. The 55 μm spatial resolution achievable with this approach is demonstrated through imaging of aUCNPs in PDMS (polydimethylsiloxane) micro-wells, showing resolution of micrometer-scale targets with single-pixel precision. INSITE imaging of intratumoral NaEr0.8Yb0.2F4 aUCNPs shows a signal-to-background ratio of 9, limited only by photodiode dark current and electronic noise. Conclusion: This work demonstrates INSITE imaging of aUCNPs in tumors, achieving an imaging platform that is thinned to just a 25 μm-thin, planar form-factor, with both NIR-I and NIR-II excitation. Based on a highly paralleled array structure INSITE is scalable, enabling direct coupling with a wide array of surgical and robotic tools for seamless integration with tissue actuation, resection or ablation.

The value of transperineal apical prostate biopsy in predicting urethral/apical margin status after radical prostatectomy

PURPOSE

To investigate potential preoperative predictors of urethral or apical positive surgical margin (PSM) and the value of apical prostate biopsy in predicting urethral/apical margin status after radical prostatectomy (RP).

METHODS

A total of 531 patients who underwent RP during 2010 to 2017 at West China Hospital were enrolled in this retrospective study. Preoperative and postoperative factors including age, BMI, PSA, clinical T stage and biopsy Gleason score were analyzed. Univariate analysis and logistic regression were used to find out the potential predictive factors for PSM. Two logistic regression models were built to evaluate the role of apical prostate biopsy in predicting urethral/apical margin status.

RESULTS

The overall PSM rate was about 30.1% (160/531) and 97 of them were reported urethral/apical PSM. The incidence of urethral or apical PSM in patients with positive cores in the apical prostate was higher than those without (23.0% vs 9.9%, P < .001). We further found that the multivariable model with positive apical prostate biopsy could significantly increase the predictive value of urethral or apical PSM status (AUC: 0.744 vs 0.783, P = .016). Our analysis also showed that neo-adjuvant hormone therapy was an independent protective factor for urethral or apical PSM in patients with positive apical prostate biopsy, but not all patients.

CONCLUSION

This study revealed the necessity of apical prostate biopsy to predict the risk of apical or urethral PSM. In clinical practice, neo-adjuvant hormone therapy should be given when patients with positive apical prostate biopsy to reduce the presence of PSM, especially patients with high/very high risk prostate cancer.

Positive surgical margins at radical prostatectomy in the United States: Institutional variations and predictive factors

INTRODUCTION

Positive surgical margins (PSMs) are associated with treatment failure after radical prostatectomy (RP) for patients with prostate cancer (CaP). We investigated institutional variations in PSM after RP, as well as clinical and demographic factors predicting PSM.

PATIENTS AND METHODS

Patients undergoing RP for clinically localized CaP were identified in the National Cancer Database in 2010 to 2013 and clinicodemographics were recorded. Treating institution was defined as academic (AMC) or nonacademic medical centers (nAMC). The primary outcome was the PSM rate. Multivariable logistic regression and propensity matching with inverse probability treatment weighing were used to both compare outcomes between AMC and nAMC and to identify predictors of PSM following RP.

RESULTS

A total of 167,260 patients met our inclusion criteria. PSM rate was significantly lower in patients treated at AMC (13,435, 18.9%) compared with 22,145 (23.0%) in those treated at nAMC (P < 0.01). The difference between PSM rate in AMC and nAMC was more pronounced in lower volume centers while it was not significant in higher volume centers. On multivariable analysis, age, race, prostate-specific antigen (PSA), biopsy Gleason score, comorbidity profile, insurance type, income, and treatment facility were significantly associated with PSM rate.

CONCLUSION

PSM rates appear to be lower at AMC and higher volume facilities, which can potentially reflect institutional differences in surgical quality. In addition, we identified several socioeconomic and demographic factors that contribute to the likelihood of PSM following RP for localized CaP, suggesting potential systematic variation in the quality of surgical care. The cause of this variation warrants further investigation and evaluation.

Impact of margin status on survival after surgery for sinonasal squamous cell carcinoma

BACKGROUND

Sinonasal squamous cell carcinoma (SNSCC) is the most common malignancy of the paranasal sinuses. Surgery is the mainstay of treatment, yet positive surgical margins (PSM) are common and the prognostic impact on overall survival (OS) is mixed. Given the heterogeneity of impact of PSM on OS within the literature, we hypothesized that extent of tumor extirpation (microscopic PSM vs macroscopic PSM) may play a role in OS.

METHODS

Patients with SNSCC were identified in the National Cancer Database (NCDB, n = 7808). Of these, 4543 patients underwent surgery, 3265 patients underwent nonsurgical therapy. Kaplan-Meier curves were used to compare OS between negative surgical margin (NSM), micro-PSM, and macro-PSM cohorts vs patients undergoing primary nonsurgical therapy in a propensity-score-matched analysis. Multivariable analysis of factors associated with macro-PSM was also performed.

RESULTS

One thousand thirty-three (22.0%) of the surgery patients had PSM, and approximately half (n = 521, 50.6%) of these had macro-PSM. When compared with nonsurgical treatment, propensity-score-matched results demonstrated improved OS in patients with NSM and micro-PSM (p < 0.001), but macro-PSM patients did not demonstrate improvement (p = 0.20). Tumor within the paranasal sinuses and advanced nodal classification (N2/N3) (odds ratio [OR], 1.18; p = 0.02; and OR, 15.09; p = 005, respectively) was associated with increased odds of macro-PSM on multivariable analysis.

CONCLUSION

We demonstrate that the degree of tumor extirpation correlates with OS. Macro-PSM did not confer a benefit to OS when compared with nonsurgical therapy, and factors including tumor location and advanced nodal status affect whether surgery will result in macro-PSM. Given these findings, informed, shared decisionmaking between patient and surgeon regarding nonsurgical alternatives should occur before electing to proceed with surgery in SNSCC.

The Sentinel Margin: Intraoperative Ex Vivo Specimen Mapping Using Relative Fluorescence Intensity

PURPOSE

Despite major advancements in surgical oncology, the positive margin rate for primary head and neck cancer resection remains around 15%-30%. In particular, the deep surface margin is the most challenging to adequately assess. Inadequate margins are directly correlated to poor survival, and as such, mitigation of these rates is critical to improve patient outcomes. We have developed an ex vivo imaging strategy that utilizes fluorescence intensity peaks (relative to background signal) of an injected anti-EGFR antibody conjugated to a fluorescent probe to locate potential close or positive margins on the deep surface of the resected tumor specimen.

EXPERIMENTAL DESIGN

Twelve patients with head and neck cancer scheduled for surgery received systemic administration of a tumor-specific contrast-agent (panitumumab-IRDye800CW). After surgical resection, the tumor specimen was imaged using a fluorescence imager. The three highest fluorescence intensity-peaks on the deep surface of the specimen were isolated and correlated to histology to determine the margin distance at these regions.

RESULTS

Relative fluorescence peak intensities identified the closest margin on the deep surface of the specimen within 2.5 minutes. The highest intensity peak consistently (100%) detected the closest margin to the tumor. The difference in tumor margin distance between the first and second highest fluorescence intensity peak averaged 2.1 ± 1.4 mm. The tumor-margin difference between the second and third highest peak averaged 1.6 ± 0.6 mm.

CONCLUSIONS

Fluorescence intensity peaks can identify the region on the specimen where tumor is closest to specimen's edge on the deep surface. This technique could have broad applications in obtaining adequate margins in oncological surgery.

Emerging Fluorescent Molecular Tracers to Guide Intra-Operative Surgical Decision-Making

Fluorescence imaging is an emerging technology that can provide real-time information about the operating field during cancer surgery. Non-specific fluorescent agents, used for the assessment of blood flow and sentinel lymph node detection, have so far dominated this field. However, over the last decade, several clinical studies have demonstrated the great potential of targeted fluorescent tracers to visualize tumor lesions in a more specific way. This has led to an exponential growth in the development of novel molecular fluorescent contrast agents. In this review, the design of fluorescent molecular tracers will be discussed, with particular attention for agents and approaches that are of interest for clinical translation.

Anti-Claudin-1 Conjugated to a Near-Infrared Fluorophore Targets Colon Cancer in PDOX Mouse Models

INTRODUCTION

Claudins are tight-junction proteins, which maintain an epithelial barrier in normal colon cells. Overexpression of Claudin-1 has been implicated for development of colon cancer. We postulated that Claudin-1 may be a useful target in near-infrared imaging and fluorescence-guided surgery.

METHODS

We conjugated Claudin-1 antibody to LI-COR IR800DyeCW (Claudin-1-IRDye800CW). Western blotting of 9 human colon cancer cell lysates was performed. Animal imaging was performed with the LI-COR Pearl Trilogy Fluorescence Imaging System. A dose-response study was carried out with subcutaneous LS174T colon cancer cell line models. Increasing doses of Claudin-1-IRDye800CW via tail vein injection were administered to three groups of mice. Two groups of mice were used as controls (antibody alone, and dye alone). In vivo imaging was performed at 24, 48, and 72 h after administration of the conjugated dye. Orthotopic implantation of patient-derived tumors and cell lines was performed and peritoneal carcinomatosis models were created. After tumor growth, mice were administered Claudin-1-IRDye800CW and imaged in vivo 48 h later. The mice were euthanized and laparotomy was performed to assess internal organs and toxicity.

RESULTS

Western blotting revealed that all colon cancer cell lysates expressed varying amounts of Claudin-1. All tumors demonstrated strong and specific fluorescence labeling at 800 nm, even with the lowest dose of 12.5 μg of Claudin-1-IRDye800CW.

CONCLUSIONS

Claudin-1 is a useful target for near-infrared antibody-based imaging for visualization of colorectal tumors for future use in fluorescence-guided surgery.

Comparison of posterior rectal dissection techniques during rectosigmoid colon resection as part of cytoreductive surgery in patients with epithelial ovarian cancer: Close rectal dissection versus total mesorectal excision

OBJECTIVE

The aim of this study was to evaluate the clinical outcomes of close rectal dissection (CRD) compared with those of total mesorectal excision (TME) as the posterior rectal dissection procedure during rectosigmoid colectomy performed as part of cytoreductive surgery in patients with epithelial ovarian cancer.

METHODS

We retrospectively reviewed the medical records of 163 patients who underwent posterior rectal dissection for rectosigmoid resection, including low anterior resection or subtotal colectomy, as part of ovarian cancer surgery from 2006 to 2018. The TME technique was mainly performed by colorectal surgeons, and the CRD technique preserving the mesorectal tissue was performed by an experienced gynecologic oncology surgeon. The patients were divided into the TME group and the CRD group, and their clinical outcomes were analyzed.

RESULTS

A total of 163 patients with ovarian cancer underwent rectosigmoid colon resection. Among the patients, 87 (53.4%) underwent CRD and 76 (46.6%) underwent TME as the posterior rectal dissection technique. The disease severity according to FIGO stage (p = .390) and the residual disease status (p = .412) were not statistically different between the 2 groups. However, the postoperative incidences of anastomotic leakage (p = .045) and prolonged ileus (>7 days, p = .055) were higher in the TME group. The pelvic recurrence rate and progression-free survival did not differ between the 2 groups (p = .663 and .790, respectively).

CONCLUSIONS

Considering the perioperative outcomes, CRD may be an alternative technique for rectal dissection in ovarian cancer with less perioperative morbidity and equivalent oncologic outcomes.

New Developments in Dual-Labeled Molecular Imaging Agents

Intraoperative detection of tumors has had a profound impact on how cancer surgery is performed and addresses critical unmet needs in surgical oncology. Tumor deposits, margins, and residual cancer can be imaged through the use of fluorescent contrast agents during surgical procedures to complement visual and tactile guidance. The combination of fluorescent and nuclear contrast into a multimodality agent builds on these capabilities by adding quantitative, noninvasive nuclear imaging capabilities to intraoperative imaging. This review focuses on new strategies for the development and evaluation of targeted dual-labeled molecular imaging agents while highlighting the successful first-in-human application of this technique.

Chinese sesame stick-inspired nano-fibrous scaffolds for tumor therapy and skin tissue reconstruction

Surgery is a common treatment to remove the solid skin tumors. It is of great importance to eliminate the remaining tumor cells and achieve the simultaneous tissue reconstruction after surgery for improving life quality of cancer patients. Inspired by the designing strategy and fabrication method of Chinese sesame sticks, a Chinese sesame stick-like scaffold is developed by spin coating of CaCuSi₄O₁₀ nanoparticles (NPs) on the surface of electrospun fibers for tumor therapy and skin tissue reconstruction. The CaCuSi₄O₁₀ NPs can transform near-infrared light energy into heat energy, showing the photothermal conversion efficiency of 33.8%. After coating of the CaCuSi₄O₁₀ NPs on the fibers, the prepared scaffolds exhibit the Chinese sesame stick-like structure and achieve bifunction with both tumor killing and skin tissue reconstruction capacities. The CaCuSi₄O₁₀ NPs endow the scaffolds with photothermal ablation potential to rapidly kill the in vitro tumor cells. Furthermore, Chinese sesame stick-like scaffolds effectively inhibit in vivo tumor growth at the early stage and accelerate healing of cancer surgery-caused wounds at the later stage in tumor-bearing mice. Additionally, the composite scaffolds promote chronic wound healing by stimulating in vivo angiogenesis and re-epithelization, harnessing locally release of bioactive Cu²⁺ and SiO₄^4- ions from the CaCuSi₄O₁₀ NPs. Therefore, the Chinese sesame stick-inspired scaffolds may lay a solid foundation for clinical treatment of cancers and cancer surgery-induced tissue damage.