University of Groningen Clinical application of near infrared fluorescence imaging in solid cancers Voskuil, Floris

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Clinical application of near infrared fluorescence imaging in solid cancers

Voskuil, Floris

DOI:

10.33612/diss.151946702

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Publication date: 2021

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Voskuil, F. (2021). Clinical application of near infrared fluorescence imaging in solid cancers: Enhancing surgical accuracy by lighting up tumors. University of Groningen. https://doi.org/10.33612/diss.151946702

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CHAPTER 7 Summary, general discussion

and future perspectives

Floris J. Voskuil1

1_{Department of Oral & Maxillofacial Surgery, University of Groningen, University Medical Center}

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155 SUMMARY AND GENERAL DISCUSSION

During the recent decades, encouraging progress has been made in the treatment of patients with solid cancers, contributing to improvements in disease-free survival rates and quality of life. Although different per tumor type, a portion of this progression can be attributed to advancements in the field of medical oncology with the use of next generation chemotherapy, targeted therapy and immunotherapy 1_{. In addition, it can be expected that the current use of novel radiotherapy}

techniques, such as protonbeam radiotherapy 2_{, will even further increase treatment outcomes,}

and eventually can lead to a further increase in disease-free and overall survival. For surgical oncology, progress has been made in surgical techniques such as robotic surgery, and surgical navigation such as pre-operative 3D planning tools and neuronavigation. However, over the last decades, there is a lack of significant improvements in intraoperative techniques that can be applied for margin assessment. To date, imaging techniques that can be used during surgical resection of cancers to accurately differentiate cancerous from non-cancerous tissue, maximizing the removal of cancerous tissue, while minimizing removal of non-cancerous tissue are not widely available 3_{. Despite efforts to implement conventional imaging modalities such as CT, MRI}

or ultrasound intraoperatively, this is not widely adapted nor did it have the impact on improving surgical resections as anticipated. As a result, surgeons still rely on their experience and visual and tactile information during cancer surgery. Since the vast majority of patients with solid cancers will receive surgical resection at a certain point during their treatment plan, a technique which can be used real-time for tissue identification can further improve treatment outcomes, preventing over- and undertreatment. Intraoperative fluorescence imaging (FI) is a novel technique which has the potential to improve clinical decision-making during cancer surgery, including the identification of small primary or synchronous tumor deposits, selection of metastatic lymph nodes, assessment of tumor margins and detection of residual disease.

In general, FI consists of the application of a targeted optical fluorescent imaging agent that will selectively accumulate in the target tissue and subsequently can be visualized by a dedicated imaging system which can qualitatively and quantitatively detect the fluorescence. Although auto-fluorescence imaging, the concept of using naturally occurring fluorescence to enhance tissue identification, and the use of non-targeted fluorescence imaging agents in FI is widely studied (e.g. indocyanine green), a growing consensus is arising that these techniques might not facilitate adequate and reliable target-specificity and reproducibility at a level that is mandatory in oncological surgery 4_{and evidence-based medicine in general. FI comes with several advantages}

over other imaging techniques, since it is able to generate high resolution and sensitivity images without the use of radioactive substances. Moreover, FI imaging systems are considerably less expensive compared to radioactive imaging techniques, and are implementable without major logistical challenges. Contrary, FI has a limited penetration depth of up to several millimeters and consequently, does not facilitate whole body imaging. These limitations are acceptable for intraoperative purposes since only the outer most millimeters of tissue are of interest for cancer detection and margin assessment during surgery as surgeons resect tissue millimeter by millimeter, not centimeters. In addition, it has been shown that FI can easily be incorporated in the current standard of care 5-10_.

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In this thesis, the clinical applicability was evaluated of three classes of targeted fluorescence imaging agents (i.e. small peptide-based, antibody-based and nanoparticle micelle-based) in a variety of solid cancer types (i.e. head and neck cancer, breast cancer, esophageal cancer and colorectal cancer), as well as in their pre-cancerous precursors (i.e. Barett’s esophagus and colorectal polyps). Last, the additional value of FI in the histopathological evaluation of freshly excised tissue was explored, so called fluorescence-guided pathology and we evaluated current and future imaging techniques that have the potential to be applicable in intraoperative pathology assisted surgery (IPAS). IPAS will be applicable in the so-called ‘golden-hour’, the time-frame in which the surgical procedure often still is ongoing and a surgeon is able to adapt the surgical strategy based on the obtained imaging data from the specimen during a surgical resection.

Chapter 1 provides a brief introduction to the subject as well as an outline of the thesis. Chapter 2 and Chapter 3 focus on the application of fluorescence imaging techniques that can enhance target detection in the upper and lower digestive tract. First, a clinical study was performed that investigates the optical imaging agent EMI-137, targeting the c-Met receptor, for the detection of Barrett’s Esophagus (BE), which is described in Chapter 2. BE is a pre-cancerous stage of the mucosa of the esophagus, which often progresses to esophageal adenocarcinoma (EAC). Unfortunately, current routine surveillance by high-definition white-light endoscopy (HD-WLE) is prone to sampling error, resulting in delayed detection 11,12_{, since identification of the BE}

lesion by the naked eye is challenging.

A tool that can guide the endoscopist in selectively performing biopsies is therefore desired, and denominated as a ‘red-flag’ technique. In this study, it was shown that fluorescence molecular endoscopy (FME) using EMI-137 was feasible and safe. Moreover, FME was able to identify 16/18 (89%) BE lesions detected using HD-WLE correctly, although it must be noted that no additional BE lesions were detected using FME. It was shown that it was feasible to perform FME both after intravenous and topical administration of EMI-137. Whereas intravenous administration resulted in a more homogenous tracer distribution in the target tissue of interest, the advantage of topical administration is the fast generation of contrast and lower risk for toxicity. Unfortunately, the c-Met expression in the BE lesions varied significantly between lesions, which could hamper clinical implementation. Moreover, it was shown that a physiological c-Met expression was observed in the gastric foveolar epithelium, which is clinically relevant, since the vast majority of BE lesions is located at the gastroesophageal junction, therefore limiting the discriminative strength at this location. Overall, it could be concluded that a tumor-to-background ratio (TBR) of 1.12-1.50 might be insufficient for adequate discrimination between the target and the surrounding tissue using EMI-137. All FME findings were confirmed by Multi-Diameter Single-Fiber Reflectance / Single- Fiber Fluorescence (MDSFR/SFF) spectroscopy measurements, a quantitative technique that obtains the intrinsic fluorescence values of the fluorophore by correcting for the tissue optical properties 13,14_.

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As the field of FME is rapidly progressing 9,10,15-18_{, a standardized method for FME studies is}

highly relevant for the comparison between patients, studies and centers, especially in early phase clinical trials which necessitate a rapid go/no-go decision with as limited resources as possible (e.g. minimal patient burden, costs and/or logistics). In the current study, six crucial outcome parameters that suited the clinical workflow were identified, both during the endoscopic procedure as during the pathological processing of the tissue. These outcome parameters may serve as a structured guidance for evaluation of a novel fluorescent tracer in early phase FME studies and can be implemented in future FME study designs.

Chapter 3 describes the application of EMI-137 for the detection of pre-malignant colorectal polyps, which can progress to colorectal cancer (CRC). As the majority of CRCs develop from a colorectal polyp, a technique that can reliably identify these polyps might facilitate early detection and eventually might lead to improved patient outcomes 19,20_{. Since identification of colorectal}

polyps by HD-WLE comes with a detection miss-rate of up to 22% in the general population 21_,

the need for novel techniques which can enhance detection and the accuracy is evident. Previously, it has been shown that EMI-137 administrated three hours prior to colonoscopy, has the potential to detect additional colorectal polyps that were initially missed by conventional HD-WLE 17_{. Since administering EMI-137 three hours prior to colonoscopy might hamper further}

clinical implementation due to logistic challenges, shorter dosing-to-imaging intervals were investigated. In this study, it was shown that no differences in TBRs were found between the 1, 2 or 3-hour dosing-to-imaging intervals, therefore suggesting that already a one hour interval might be sufficient for the detection of colorectal polyps. Again, FME findings were confirmed by MDSFR/SFF spectroscopy to correct for tissue optical properties, thereby showing the intrinsic fluorescence.

The colorectal polyps showed a heterogenous expression of c-Met, however, in this study, this did not influence macroscopic FME results. As it was shown that the fluorescence in the polyps did not further increase after one hour, but background fluorescence did slightly decrease in later time-points, it might be relevant to investigate a lower dose of EMI-137 that might further decrease background fluorescence, thus potentially increasing TBR and detection sensitivity. In this study, only patients with a known advanced adenoma, detected during a previous colonoscopy, were included. One might argue that the investigated population is therefore not representative for a normal population that undergoes screening in case an average risk of CRC is present. In general, it was concluded that the clinical applicability of EMI-137 could be expanded by showing that a one hour dosing-to-imaging generates a sufficient TBR for the detection of colorectal cancer polyps. Subsequent phase II/III studies can now commence to investigate the use of EMI-137 for colorectal polyp detection in a large general screening population.

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In Chapter 4 and Chapter 5, a surgical application of targeted fluorescence imaging was studied. In Chapter 4, an EGFR-targeted fluorescent imaging agent, cetuximab-800CW, was investigated in patients diagnosed with Head and Neck Squamous Cell Carcinoma (HNSCC). Since the epidermal growth factor receptor (EGFR) is overexpressed in more than 90% of all HNSCC, cetuximab-800CW has the potential to accurately identify HNSCC lesions.

Currently, head and neck cancer surgery faces tumor-positive margin rates of up to 23%, which is the highest overall rate for tumors affecting both genders 22-25_{. Consequently, this has a}

significant impact on treatment outcome, since tumor-positive margins rates are independently associated with an increased risk of local recurrence and a decreased overall survival 25_{. Moreover,}

tumor-positive margins cause a relative risk of death of 11.61 (p=0.0013) compared to patients with tumor-negative margins 25_{. The group of Rosenthal et al. reported in 2015 for the first time}

on the use of cetuximab-800CW in HNSCC patients 5_{, and showed that cetuximab-800CW was}

safe to use up to a dose of 62.5mg/m2_{combined with 10mg or 100mg unlabeled cetuximab}

as predosing. An unlabeled pre-dose might increase off-target receptor occupancy and tissue sequestration 26_{, thereby increasing the TBR. The results were promising for HNSCC visualization.}

In this study, cohorts administered with flat, single doses of cetuximab-800CW were compared with cohorts that received 75mg unlabeled cetuximab one hour prior to cetuximab-800CW. It was found that a dosing strategy of 75mg ‘cold’ cetuximab followed by 15mg labelled cetuximab-800CW resulted in the optimal TBR and was well tolerated in HNSCC patients. In this study consisting of 15 patients, four patients had a tumor-positive margin (27%), which were all identified correctly immediately after excision during the initial surgery, denominated as the

back-table phase.

In this study, we used a wide-field fluorescence camera optimized for IRDye800CW detection, as well as a custom-made naso-endoscopic modification. Here, a flexible naso-endoscope was attached to the fluorescence camera to visualize areas in the oral cavity otherwise difficult to access. Moreover, to overcome the influence of external factors such as ambient light, light exposure homogeneity, and angle of illumination, which is highly relevant in the operation room, we performed MDSFR/SFF spectroscopy to quantify the fluorescence in this dose-escalation study, as reported previously 6,10_{. The dosing scheme which was considered to be optimal in}

this study was considerably lower than reported in previous studies, thereby limiting the risk for potential side-effects. Other studies used an imaging system that was optimized for Indocyanine Green (ICG) fluorescence but not for IRDye800CW detection, which might have contributed to the conclusion of the differences in their optimal dose of 25mg/m2_.

Back-table FI, which refers to imaging the excised specimen immediately after excision, can identify areas suspected for tumor-positive margins. This allows the surgeon to perform an immediate re-resection or a FI-guided biopsy for fresh frozen sectioning analysis, while the patient is still anesthetized. The positive results of this specimen-driven approach, performed in a controlled and standardized setting, are congruent with other studies performed by our group and others 6,27-29_{. Although obtaining lower rates of tumor-positive margins is an essential}

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element for increasing treatment outcomes in HNSCC patients, a multi-disciplinary approach remains necessary since local recurrence is reported in up to 11% of patients with tumor-negative surgical margins 30,31_{. As reported previously, to date most imaging strategies focus on targeting}

on cell-surface receptors, first described by our group in 2011 4,8_{. Other strategies involve tumor}

activatable imaging agents consisting of a polycationic peptide with a fluorescent dye and a neutralizing peptide. When the linker is cleaved by tumor-specific proteases, the dye conjugated peptide enters tumor cells and is retained 32_.

Despite successes in clinical translation, one of the major drawbacks of these strategies is the lack of broad tumor applicability in a variety of cancer patients. For example, the folate receptor-α (FR-α) is largely overexpressed in ovarian cancer, but not in head and neck cancer cells 33_{. In contrast, EGFR is highly overexpressed in HNSCC}34_{, but not in breast cancer tissue. This}

can make reliance on a single tumor-specific marker for margin assessment in a broad variety of tumor types difficult. Moreover, the relatively long half-life time for monoclonal antibody (MoAb)-fluorophore conjugates, which necessitates tracer application a couple of days prior to surgery, and the ‘always-on’ design, which might limit discriminative strength, could be challenging for further clinical implementation. A potential strategy to overcome this is by targeting more ubiquitous characteristics, for example the altered metabolic environment in cancerous tissue. Due to aerobic glycolysis, first described by Nobel laureate winner dr. Otto Warburg in 1924, acidification of the extracellular pH (pH_e) occurs. This is later described as a ‘hallmark’ of cancers 35,36_,

as it has been shown that this phenomenon exists in the majority of solid cancer types 37_.

In Chapter 5 we describe the first-in-human application of a pH-activated near-infrared optical imaging agent, ONM-100. This nanoparticle-based imaging agent with exquisitely sensitive pH responses (ΔpH=0.15), was investigated in thirty patients diagnosed with different cancer types (i.e. Head and Neck Squamous Cell Cancer, Breast Cancer, Esophageal Cancer and Colorectal Cancer). We showed that, independent of the cancer type, ONM-100 was well-tolerated and able to visualize cancer tissue both in- and ex vivo in a sharply delineated fashion. Furthermore, we showed that the discriminative strength of ONM-100 between cancerous and non-cancerous tissue was highly significant, with an area under the curve of 0.9875. The broad clinical utility of ONM-100 was, although in a relatively small patient series, shown by the fact that all nine tumor-positive margins were intraoperatively detected. Moreover, one additional, clinically unnoticed satellite tumor lesion was detected in the oral cavity during FI. In addition, during histopathological processing of the tissue, FI using ONM-100 detected three additional, otherwise unnoticed satellite lesions and second primaries in the pathology specimens, which in fact had severe consequences for the post-operative treatment strategies. Unfortunately, we were not able to visualize the fluorescence distribution on a microscopic level, since ONM-100 is not membrane-bound and therefore is washed out during the standard of care processing of tissue. The limited time from dosing to imaging of 24 ± 8 hours was shown to be acceptable for clinical utility. However, in a currently ongoing phase II clinical trial, an even more limited interval is investigated, since only a few hours prior to surgery might be preferable in terms of clinical implementation. A broad clinical utility of ONM-100 is further investigated by the inclusion of several other solid tumor types, such as ovarian and prostate cancer (NCT03735680).

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As shown throughout this thesis, implementation of novel imaging techniques can support the detection of cancer tissue during endoscopy and surgical procedures. Since there is growing evidence in the field of fluorescence-guided surgery that a specimen-driven back-table assessment may be superior to a wound bed-driven assessment due to better visualization, standardization and less sampling error 38-42_{, focusing on the excised specimen seems justified.}

Interestingly, largely based on the above-mentioned factors, the American Joint Committee on Cancer (AJCC) adopted a specimen-driven intraoperative assessment as the standard of care in the current guidelines 43_{. Intraoperative pathology assisted surgery (IPAS) is an emerging concept}

that entails a different yet versatile approach between surgeons and pathologists in the treatment of diseases. In Chapter 6, we discuss a variety of major, innovative imaging techniques which have the potential to be used intraoperatively on the freshly excised tissue. By ‘implementing’ three typical use cases which are highly representative in daily practice in oncological surgery, we show the potential added value of IPAS for clinical decision-making. In this review, based on current literature, we expect that implementing IPAS in the current standard of care can lead to a paradigm shift in the field of the pathological assessment of surgical specimens, immediate reporting to the attending surgeon in the OR for reasons of margin positivity or negativity and thus eventually to an improvement in treatment outcomes. It is obvious that a harmonious cooperation between surgeons, pathologists, engineers and image-analysis experts is a major requirement for further exploring and implementing the concept.

FUTURE PERSPECTIVES

As shown in this thesis, the translation of optical imaging agents towards the clinic has the potential to alter clinical decision-making and it can be expected that it will be rapidly expanded the upcoming years, illustrated by the fact that larger phase II/III clinical trials are currently being performed (e.g. NCT03134846 and NCT03659448). However, a potential pitfall for clinical implementation is the lack of comparability between different studies and centers. This can be partly attributed to the fact that different methodologies, analyses and outcome parameters are being used, although suggestions for standardized methodologies are upcoming

6,44,45_{. However, at least as important is the lack in standardization of imaging techniques. By}

interpreting fluorescence results, one should be aware that, independent of the biodistribution of the imaging agent, fluorescence intensities are influenced by multiple factors, such as tissue optical properties, camera to surface distance and dynamic range of the fluorescence camera

46-48_{. As the field is rapidly progressing, a currently unmet need for standardized correction of}

these factors is highly desirable. MDSFR/SFF spectroscopy is a technique for quantification of the intrinsic fluorescence of the imaging agent by correcting for tissue scattering and absorption. Improvements need to be achieved in the speed of the (post)-processing time and the field-of-view and penetration depth of this technology. Moreover, it remains questionable if pinpoint measurements are reliable for larger volumes of tissue, and thus feasible for margin assessment in the clinical setting.

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Another point of concern that needs attention is the limited penetration depth of near infrared (NIR) fluorescence, which is currently up several millimeters (±2-5mm). Although mucosal or skin lesions such as gastrointestinal tumors or head and neck cancers are easily accessible for NIR FI, the detection of deeper-seated carcinoma’s such as breast cancer are not, and may need a different clinical approach. Multi spectral optoacoustic tomography (MSOT), a non-invasive hybrid imaging modality which detects ultrasound waves emitted by the tissue due to absorption of light of transient energy by tissue chromophores or photo-absorbing agents, has the potential to expand the clinical utility of optical imaging. MSOT comes with a high optical contrast and high depth-to-resolution ratio for deep-tissue imaging 49_{. To date, several clinical studies have been performed}

on visualizing endogenous contrast agents such as hemoglobin, lipid, melanin among others using MSOT 50-52_{. Despite promising results, clinical applicability in the field of surgical oncology}

remains challenging due to limited specificity of the measured parameters. Recently, the use of exogenous imaging agents for MSOT has been studied. However, to date there is a lack of dedicated targeted exogenous optoacoustic imaging agents which produce sound, instead of

light, as is the standard for conventional FI. Therefore, translation of these exogenous imaging

agents in MSOT into clinical applications remains challenging 49_{. Agents with a low}

quantum-yield but high molecular extinction coefficients, thereby increasing detection sensitivity for MSOT imaging systems, are currently developed towards first-in-human application, which might lead to a paradigm shift in more deeper penetrating optical imaging.

Next, an item to be discussed is the focus on the excised tissue specimen for the enhanced detection of cancer. As stated previously, imaging in the ex vivo environment has advantages over the in vivo environment in terms of standardization and limited regulatory concerns regarding sterilization. By further incorporating intraoperative pathology assisted surgery in the clinic, this might alter the current standard of care, which is to date visual and manual inspection alone, time-consuming, labor-intensive and associated with inaccurate diagnosis and inter- and intra-observer variability in the interpretation of images 53_.

As stated, the interpretation of histopathology data (e.g. images of tissue slides) remains subjective in the majority of cases. This also is the case for the interpretation of fluorescence imaging data, where the interpretation of data can also be judged as (partly) subjective. The application of Artificial Intelligence (AI), which can be described as machine-based approaches that are used to attempt to make a prediction, in other words, to imitate intelligent human beings, can be used to assist in analyzing histopathology data, whether conventional or fluorescent, and is increasingly studied. Machine Learning (ML), where algorithms and techniques are used by a computer to ‘learn’ to make predictions, and Deep Learning (DL), a ML-based method based on neural networks which are ‘teached’ by examples of input variables to predict outcomes variables, which can eventually ‘teach’ itself are investigated for application in this field. As reported, DL algorithms can help identify specific patterns associated with disease 54_{. In clinical practices, it}

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has already been shown that DL is able to yield very accurate diagnostic performance, often better than a panel of clinicians 55,56_{. Independently of the exact indication, AI is thought to be of}

great value for improved, faster and less labor-intensive assessment of histopathology data 57_{. By}

combining the clinical judgement of a clinician with AI techniques, a symbiosis can occur which will lead to improved clinical decision-making. We hypothesize that within a reasonable amount of time, the application of AI for the interpretation of novel imaging data (e.g. fluorescence imaging) might further increase the quality of pathological assessment in cancer treatment.

As patients do not respond in a homogenous fashion to anti-cancer treatment, it is important to monitor the treatment response of individual patients (i.e. personalized medicine), thereby allowing to set, or adjust, a specific treatment plan for each patient. Since the clinical application of antibody treatment in a variety of diseases is rapidly progressing over the last decade, this opens up the possibility to perform treatment monitoring and provides information on the biodistribution by fluorescently labeling the antibody of interest, which currently is studied by our group investigating the distribution of vedolizumab in the colon. We hypothesize that, as already shown in a phase I trial in colorectal cancer patients, FI can serve as a selection tool for personalized treatment 58_{. Now we have shown that FI can assist in diagnosing cancer, the next}

subsequent step is to monitor treatment response.

Although not discussed in this thesis, there is large interest in using light not only for the detection of cancers, but also for (targeted) treatment. Photodynamic therapy (PDT) is a good example to illustrate this, where photosensitizing agents are administered and are activated by light with a specific wavelength to kill cancer cells 59_{. It is hypothesized that in the not to distant}

future, as next step, diagnosis and therapeutics can be combined, denominated as theranostics, for the treatment of solid cancers. By first identifying the disease using low energy illumination for fluorescence imaging, the tumor can be excised precisely during conventional excision. After the excision has been performed, any residual (microscopic) cancer lesions can subsequently be treated with high power illumination which generates reactive oxygen species and thereby inducing cell death, as already shown in a phase II clinical trial 60_.

The current thesis and other studies show that micro-dosing can be used for investigating the biodistribution during drug development. By lowering the barrier for clinical use and providing fast and efficiently first in-human data, using a standardized method to correlate in vivo data to ex

vivo microscopic data, micro-dosing studies can generate critical go/no-go decisions before large

investments are needed 6,61_{. Interesting developments are ongoing where imaging agents are}

both fluorescently and nuclear labeled, to perform both PET and fluorescence imaging. The use of smart-activatable imaging agents can be expanded into therapeutics, as one can hypothesize that the loading of fluorophores in the current studied smart-activatable imaging agents, such as the nanoparticle-based imaging agent described in Chapter 5, can be replaced by therapeutic agents. This is in line with data from related fields of research, where photo switchable compounds can selectively deliver a drug in the tissue of interest 62,63_.

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163 CONCLUSION

This thesis describes that the application of fluorescence imaging potentially may profoundly alter clinical decision-making in patients suspected of, or diagnosed with, solid cancers. The use of exogenous optical imaging agents specifically targeted for the disease enables real-time information, thereby allowing the clinician to immediately act on the obtained information. This can lead to improved treatment outcomes and eventually to improved disease-free survival rates. The development of next generation smart-activatable fluorescence imaging agents, which can be used for both fluorescence-guided treatment and verification of the biodistribution, has the potential to rapidly evolve in smart-activatable highly-tumor specific generic drug-carriers, which can have major effects on oncological treatment in the near future as a true theranostic agent serving the classical treatment modalities involved which are medical oncology, radiotherapy and surgery.

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REFERENCES

Tsimberidou, A.-M. Targeted therapy in cancer. Cancer Chemother Pharmacol 76, 1113–1132 (2015). Gotwals, P. et al. Prospects for combining targeted and conventional cancer therapy with immunotherapy. Nat Rev Cancer 17, 286–301 (2017).

Lee, J. Y. K. et al. Review of clinical trials in intraoperative molecular imaging during cancer surgery. J Biomed Opt 24, 1–8 (2019).

Debie, P. & Hernot, S. Emerging Fluorescent Molecular Tracers to Guide Intra-Operative Surgical Decision-Making. Front Pharmacol 10, 510 (2019).

Rosenthal, E. L. et al. Safety and Tumor Specificity of Cetuximab-IRDye800 for Surgical Navigation in Head and Neck Cancer. Clin. Cancer Res. 21, 3658–3666 (2015).

Koller, M. et al. Implementation and benchmarking of a novel analytical framework to clinically evaluate tumor-specific fluorescent tracers. Nat Commun 9, 37–39 (2018).

Harlaar, N. J. et al. Molecular fluorescence-guided surgery of peritoneal carcinomatosis of colorectal origin: a single-centre feasibility study. Lancet Gastroenterol Hepatol 1, 283–290 (2016).

van Dam, G. M. et al. Intraoperative tumor-specific fluorescence imaging in ovarian cancer by folate receptor-alpha targeting: first in-human results. Nat Med 17, 1315–1319 (2011).

Hartmans, E. et al. Potential Red-Flag Identification of Colorectal Adenomas with Wide-Field Fluorescence Molecular Endoscopy. Theranostics 8, 1458–1467 (2018).

Nagengast, W. B. et al. Near-infrared fluorescence molecular endoscopy detects dysplastic oesophageal lesions using topical and systemic tracer of vascular endothelial growth factor A. Gut 68, 7–10 (2019). Spechler, S. J., Fitzgerald, R. C., Prasad, G. A. & Wang, K. K. History, molecular mechanisms, and endoscopic treatment of Barrett’s esophagus. Gastroenterology 138, 854–869 (2010).

Bird-Lieberman, E. L. et al. Molecular imaging using fluorescent lectins permits rapid endoscopic identification of dysplasia in Barrett’s esophagus. Nat Med 1–8 (2019).

Middelburg, T. A., Hoy, C. L., Neumann, H. A. M., Amelink, A. & Robinson, D. J. Correction for tissue optical properties enables quantitative skin fluorescence measurements using multi-diameter single fiber reflectance spectroscopy. J Dermatol Sci 79, 64–73 (2015).

Kanick, S. C., Robinson, D. J., Sterenborg, H. J. C. M. & Amelink, A. Extraction of intrinsic fluorescence from single fiber fluorescence measurements on a turbid medium. Opt Lett 37, 948–950 (2012).

Atreya, R. et al. In vivo imaging using fluorescent antibodies to tumor necrosis factor predicts therapeutic response in Crohn’s disease. Nat Med 20, 313–318 (2014).

Joshi, B. P. et al. Detection of Sessile Serrated Adenomas in the Proximal Colon Using Wide-Field Fluorescence Endoscopy. Gastroenterology 152, 1002–1013.e9 (2017).

Burggraaf, J. et al. Detection of colorectal polyps in humans using an intravenously administered fluorescent peptide targeted against c-Met. Nat Med 21, 955–961 (2015).

Tjalma, J. J. et al. Molecular Fluorescence Endoscopy Targeting Vascular Endothelial Growth Factor A for Improved Colorectal Polyp Detection. J. Nucl. Med. 57, 480–485 (2016).

Arnold, M. et al. Global patterns and trends in colorectal cancer incidence and mortality. Gut 66, 683– 691 (2017).

Leslie, A., Carey, F. A., Pratt, N. R. & Steele, R. J. C. The colorectal adenoma-carcinoma sequence. Br J Surg 89, 845–860 (2002).

Stoffel, E. M. et al. Missed adenomas during colonoscopic surveillance in individuals with Lynch Syndrome (hereditary nonpolyposis colorectal cancer). Cancer Prev Res (Phila) 1, 470–475 (2008).

Wong, L. S. et al. Influence of close resection margins on local recurrence and disease-specific survival in oral and oropharyngeal carcinoma. Br J Oral Maxillofac Surg 50, 102–108 (2012).

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

(14)

165 Woolgar, J. A. & Triantafyllou, A. A histopathological appraisal of surgical margins in oral and oropharyngeal cancer resection specimens. Oral Oncol 41, 1034–1043 (2005).

Gephardt, G. N. & Zarbo, R. J. Interinstitutional comparison of frozen section consultations. A college of American Pathologists Q-Probes study of 90,538 cases in 461 institutions. Arch Pathol Lab Med 120, 804–809 (1996).

Orosco, R. K. et al. Positive Surgical Margins in the 10 Most Common Solid Cancers. Sci Rep 8, 56–86 (2018).

Moore, L. S. et al. Effects of an Unlabeled Loading Dose on Tumor-Specific Uptake of a Fluorescently Labeled Antibody for Optical Surgical Navigation. Mol Imaging Biol 19, 610–616 (2016).

de Jongh, S. J. et al. Back-table fluorescence-guided imaging for circumferential resection margin evaluation in locally advanced rectal cancer patients using bevacizumab-800CW. J. Nucl. Med. jnumed.119.232355 (2019).

van Keulen, S. et al. The Sentinel Margin: Intraoperative Ex Vivo Specimen Mapping Using Relative Fluorescence Intensity. Clin. Cancer Res. 25, 4656–4662 (2019).

van Keulen, S. et al. Rapid, non-invasive fluorescence margin assessment: Optical specimen mapping in oral squamous cell carcinoma. Oral Oncol 88, 58–65 (2019).

Tasche, K. K., Buchakjian, M. R., Pagedar, N. A. & Sperry, S. M. Definition of ‘Close Margin’ in Oral Cancer Surgery and Association of Margin Distance With Local Recurrence Rate. JAMA Otolaryngol Head Neck Surg 143, 1166–1172 (2017).

Nason, R. W., Binahmed, A., Pathak, K. A., Abdoh, A. A. & Sandor, G. K. B. What is the adequate margin of surgical resection in oral cancer? Oral Surg Oral Med Oral Pathol Oral Radiol Endod 107, 625–629 (2009). Nguyen, Q. T. et al. Surgery with molecular fluorescence imaging using activatable cell-penetrating peptides decreases residual cancer and improves survival. Proc Natl Acad Sci U S A 107, 4317–4322 (2010).

Sun, J. Y. et al. In vivo optical imaging of folate receptor-beta in head and neck squamous cell carcinoma. Laryngoscope 124, E312–9 (2014).

Ang, K. K. et al. Impact of epidermal growth factor receptor expression on survival and pattern of relapse in patients with advanced head and neck carcinoma. Cancer Res 62, 7350–7356 (2002).

Webb, B. A., Chimenti, M., Jacobson, M. P. & Barber, D. L. Dysregulated pH: a perfect storm for cancer progression. Nat Rev Cancer 11, 671–677 (2011).

Gillies, R. J., Raghunand, N., Garcia-Martin, M. L. & Gatenby, R. A. pH imaging. A review of pH measurement methods and applications in cancers. IEEE Eng Med Biol Mag 23, 57–64 (2004).

Volk, T., Jahde, E., Fortmeyer, H. P., Glusenkamp, K. H. & Rajewsky, M. F. pH in human tumour xenografts: effect of intravenous administration of glucose. Br J Cancer 68, 492–500 (1993).

Amit, M. et al. Improving the rate of negative margins after surgery for oral cavity squamous cell carcinoma: A prospective randomized controlled study. Head Neck 38 Suppl 1, E1803–9 (2016). Bradley, P. J., MacLennan, K., Brakenhoff, R. H. & Leemans, C. R. Status of primary tumour surgical margins in squamous head and neck cancer: prognostic implications. Curr Opin Otolaryngol Head Neck Surg 15, 74–81 (2007).

McIntosh, E. R., Harada, S., Drwiega, J., Brandwein-Gensler, M. S. & Gordetsky, J. Frozen section: guiding the hands of surgeons? Ann Diagn Pathol 19, 326–329 (2015).

Slootweg, P. J., Hordijk, G. J., Schade, Y., van Es, R. J. J. & Koole, R. Treatment failure and margin status in head and neck cancer. A critical view on the potential value of molecular pathology. Oral Oncol 38, 500–503 (2002).

Varvares, M. A., Poti, S., Kenyon, B., Christopher, K. & Walker, R. J. Surgical margins and primary site resection in achieving local control in oral cancer resections. Laryngoscope 125, 2298–2307 (2015).

7

23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42

(15)

166

Amin, M. B. et al. The Eighth Edition AJCC Cancer Staging Manual: Continuing to build a bridge from a population-based to a more ‘personalized’ approach to cancer staging. CA Cancer J Clin 67, 93–99 (2017). Tummers, W. S. et al. Recommendations for reporting on emerging optical imaging agents to promote clinical approval. Theranostics 8, 5336–5347 (2018).

Ruiz, A. J. et al. Indocyanine green matching phantom for fluorescence-guided surgery imaging system characterization and performance assessment. J Biomed Opt 25, 1–15 (2020).

Koch, M. & Ntziachristos, V. Advancing Surgical Vision with Fluorescence Imaging. Annu Rev Med 67, 153–164 (2016).

Koch, M., Symvoulidis, P. & Ntziachristos, V. Tackling standardization in fluorescence molecular imaging. Nature Photonics 12, 505–515 (2018).

Gorpas, D., Koch, M., Anastasopoulou, M., Klemm, U. & Ntziachristos, V. Benchmarking of fluorescence cameras through the use of a composite phantom. J Biomed Opt 22, 016009–13 (2017).

Upputuri, P. K. & Pramanik, M. Recent advances in photoacoustic contrast agents for in vivo imaging. Nanomed Nanobiotechnol e1618 (2020).

Stoffels, I. et al. Metastatic status of sentinel lymph nodes in melanoma determined noninvasively with multispectral optoacoustic imaging. Sci Transl Med 7, 317ra199 (2015).

Regensburger, A. P. et al. Detection of collagens by multispectral optoacoustic tomography as an imaging biomarker for Duchenne muscular dystrophy. Nat Med 25, 1905–1915 (2019).

Diot, G. et al. Multispectral Optoacoustic Tomography (MSOT) of Human Breast Cancer. Clin. Cancer Res. 23, 6912–6922 (2017).

Yu, K.-H. et al. Predicting non-small cell lung cancer prognosis by fully automated microscopic pathology image features. Nat Commun 7, 12474 (2016).

Hollon, T. C. et al. Near real-time intraoperative brain tumor diagnosis using stimulated Raman histology and deep neural networks. Nat Med 26, 52–58 (2020).

Ehteshami Bejnordi, B. et al. Diagnostic Assessment of Deep Learning Algorithms for Detection of Lymph Node Metastases in Women With Breast Cancer. JAMA 318, 2199–2210 (2017).

Hekler, A. et al. Deep learning outperformed 11 pathologists in the classification of histopathological melanoma images. Eur J Cancer 118, 91–96 (2019).

Bera, K., Schalper, K. A., Rimm, D. L., Velcheti, V. & Madabhushi, A. Artificial intelligence in digital pathology - new tools for diagnosis and precision oncology. Nat Rev Clin Oncol 16, 703–715 (2019).

Tjalma, J. J. J. et al. Quantitative fluorescence endoscopy: an innovative endoscopy approach to evaluate neoadjuvant treatment response in locally advanced rectal cancer. Gut 1–5 (2019). Rkein, A. M. & Ozog, D. M. Photodynamic therapy. Dermatol Clin 32, 415–25– x (2014).

Gillenwater, A. M. et al. RM-1929 photo-immunotherapy in patients with recurrent head and neck cancer: Results of a multicenter phase 2a open-label clinical trial. J Clin Oncol 36, 6039–6039 (2018). Paul, S. M. et al. How to improve R&D productivity: the pharmaceutical industry’s grand challenge. Nat Rev Drug Discov 9, 203–214 (2010).

Dorel, R. & Feringa, B. L. Photoswitchable catalysis based on the isomerisation of double bonds. Chem Commun (Camb) 55, 6477–6486 (2019).

Roke, D., Sen, M., Danowski, W., Wezenberg, S. J. & Feringa, B. L. Visible-Light-Driven Tunable Molecular Motors Based on Oxindole. J Am Chem Soc 141, 7622–7627 (2019)

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