Surgical margins in head and neck cancer: A contemporary review

Trends and Future Directions in Margin Analysis for Head and Neck Cancers

Margin status in head and neck cancer has important prognostic implications. Currently, resection is based on manual palpation and gross visualization followed by intraoperative specimen or tumor bed-based margin analysis using frozen sections. While generally effective, this protocol has several limitations including margin sampling and close and positive margin re-localization. There is a lack of evidence on the association of use of frozen section analysis with improved survival in head and neck cancer. This article reviews novel technologies in head and neck margin analysis such as 3-dimensional scanning, augmented reality, molecular margins, optical imaging, spectroscopy, and artificial intelligence.

Rethinking Surgical Margins: A New Approach to Predict Outcomes in Oral Squamous Cell Carcinoma

OBJECTIVE

The traditional categorical division of surgical margins using a 5 mm cutoff in oral cavity squamous cell carcinoma (OCSCC) is controversial. The primary aim of this study was to investigate the presence of an optimal cutoff point or, alternatively, assess the potential improvement in predictive value by considering the surgical margins as a continuum.

METHODS

Retrospective analysis of OCSCC patients at a tertiary medical center in 1995-2020. Clinical, pathological, and surgical data were evaluated for effect on survivability by regression analyses.

RESULTS

The cohort included 266 patients (48.1% male, mean age 65.4 ± 17.7). Patient stratification by categorical margin status yielded no significant between-group differences in survival (p = 0.54). Significance was achieved when margin distance was reevaluated as a continuous variable (p = 0.0018). Similar results were shown in local control (categorical p = 0.59 vs. continuous p = 0.06). Multivariate model excluded possible confounders. A predictive model was created to provide a more accurate prediction of survival.

CONCLUSIONS

The continuum spectrum of margin distance better predicts survival outcomes and locoregional control in OCSCC.

LEVEL OF EVIDENCE

3 Laryngoscope, 2024.

Indocyanine green uptake by human tumor and non‑tumor cell lines and tissue

Indocyanine green (ICG) is a potential promising dye for a better intraoperative tumor border definition and an improved patient outcome by potentially improving tumor border visualization compared with traditional white light guided surgery. Here, the cellular uptake of ICG in human squamous cell carcinoma (SCC026) and immortalized non-cancer skin (HaCaT) cell lines was evaluated to study the tumor-specific cellular uptake of ICG. The spatial distribution of ICG inside tumor tissue was investigated in tissue sections of head and neck squamous cell carcinoma at a microscopic level. ICG uptake and internalization was observed in living cells after 2.5 h and in the nucleus after 24 h. In dead cells, higher and faster uptake was observed. In the tissue sections, higher ICG signal intensity could be detected in connective tissue and surrounding clusters and blood vessels. In conclusion, no distinct ICG uptake by tumor cells was detected in cancer cell lines and tumor tissue. ICG localization in certain regions of tumor tissue appears to be a result of enhanced tissue permeability and retention, but not specific to tumor cells.

Multicenter clinical trial on functional evaluation of transoral laser microsurgery for supraglottic laryngeal carcinomas

BACKGROUND

Transoral laser microsurgery (TLM) is an accepted and effective treatment strategy for supraglottic carcinomas. Data on oncologic and to a lesser extent functional outcomes have been published by mainly European specialized single institutions. TLM for supraglottic carcinomas has never been tested in a multicenter trial on its applicability as surgical standard at every hospital.

OBJECTIVES

To test the efficacy of TLM supraglottic laryngectomy (TLM-SGL) in terms of swallowing function, oncologic outcome parameters, morbidity, complications of treatment, and quality of life in a multicenter setting.

METHODS

The study is designed as a multicenter (approximately 25 centers), non-randomized, single-arm study with a targeted number of 200 previously untreated patients with squamous cell carcinomas (SCC) of the supraglottic larynx T2/T3 N0-3 M0; UICC stage II-IVa. The surgical treatment consists of TLM-SGL and elective or therapeutic uni- or bilateral selective neck dissection (SND). After pathologic risk stratification adjuvant radio- (RT) or radiochemotherapy (RCT) is indicated. Patients are followed-up for 2 years post surgically. Swallowing function is assessed by fibreoptic endoscopic evaluation of swallowing (FEES). The primary endpoint is aspiration-free swallowing at 12 months as established using FEES and defined as grade < 6 of penetration-aspiration scale (PAS). Secondary endpoints include local control, larynx preservation, overall and disease-free survival, complications and side effects of treatment, prevalence of tracheostomy and percutaneous endoscopic gastrostomy (PEG)-tube-feeding, and dysphagia-specific quality of life (QoL) assessed by the MD Anderson Dysphagia Inventory (MDADI) as well as voice-related QoL assessed by the Voice Handicap Index (VHI).

Transoral robotic surgery for oropharyngeal cancer: a systematic review on the role of margin status

INTRODUCTION

Nowadays, robotic surgery finds application in the field of head and neck in the treatment of oropharyngeal tumors. The aim of this work is to examine the efficacy of transoral robotic surgery (TORS) in performing safe oncological resections of oropharyngeal squamous cell carcinoma (OPSCC), with particular attention to the status of margins.

EVIDENCE ACQUISITION

Literature search of English-language studies focused on TORS through PubMed, the Cochrane Library and EMBASE databases. A total of 431 papers returned to search, but only 24 met the inclusion criteria. The review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) Guidelines.

EVIDENCE SYNTHESIS

Within the selected studies, the overall rate of OPSCC positive margins following TORS is minimal, especially when patient selection is adequate and when TORS is used by high volume centers.

CONCLUSIONS

TORS is a very precise and viable therapeutic tool that provides good results in terms of surgical radicality with low positive margin rates and good results in terms of overall survival and disease-free survival; however, there is still a great heterogeneity in margins definition within the available literature. Consequently, even if this surgical approach is very promising, it is still challenging to draw firm conclusions nowadays.

Surgical margins in head and neck squamous cell carcinoma: A narrative review

Head and neck squamous cell carcinoma (HNSCC), a prevalent and frequently recurring malignancy, often necessitates surgical intervention. The surgical margin (SM) plays a pivotal role in determining the postoperative treatment strategy and prognostic evaluation of HNSCC. Nonetheless, the process of clinical appraisal and assessment of the SMs remains a complex and indeterminate endeavor, thereby leading to potential difficulties for surgeons in defining the extent of resection. In this regard, we undertake a comprehensive review of the suggested surgical distance in varying circumstances, diverse methods of margin evaluation, and the delicate balance that must be maintained between tissue resection and preservation in head and neck surgical procedures. This review is intended to provide surgeons with pragmatic guidance in selecting the most suitable resection techniques, and in improving patients' quality of life by achieving optimal functional and aesthetic restoration.

Association of the Specimen and Tumor Bed Margin Status with Local Recurrence and Survival in Open Partial Laryngectomy

Background/Objectives: Positive margins are associated with locoregional recurrence in early laryngeal cancer. The aim of this study was to evaluate the impacts of specimen-driven (ex vivo) positive margins on patients with early-stage laryngeal cancer whose tumor bed (defect-driven) margins had been negative. Methods: A retrospective study was performed on 60 consecutive T1b/T2 glottic cancer patients who underwent open frontolateral laryngectomy. The intraoperative margins were obtained from the tumor bed. Their recurrence and disease-free survival were evaluated. In all cases, negative margins were obtained from the surgical bed. The impact of positive margins from the specimen was evaluated in a paraffin study. Results: Among 10 patients with positive margins in the specimen, six experienced local relapse, and among 50 patients with negative margins in the specimen, three developed recurrence. The 5-year disease-free survival rates were 37.5% and 93.9%, respectively (p < 0.001; log-rank). Even with negative margins in the surgical bed, patients with positive margins in the specimen at the final histopathological examination had a 3.5-fold higher chance of developing local recurrence than those with negative margins (HR = 13.993; 95% CI: 3.479-56.281; p < 0.001; univariate Cox regression). Conclusions: Specimen-driven positive margins represent a significant risk factor for local recurrence, even under negative margins at the tumor bed.

Latin American Consensus on the Treatment of Head and Neck Cancer

Head and neck squamous cell carcinoma (HNSCC) is well known as a serious health problem worldwide, especially in low-income countries or those with limited resources, such as most countries in Latin America. International guidelines cannot always be applied to a population from a large region with specific conditions. This study established a Latin American guideline for care of patients with head and neck cancer and presented evidence of HNSCC management considering availability and oncologic benefit. A panel composed of 41 head and neck cancer experts systematically worked according to a modified Delphi process on (1) document compilation of evidence-based answers to different questions contextualized by resource availability and oncologic benefit regarding Latin America (region of limited resources and/or without access to all necessary health care system infrastructure), (2) revision of the answers and the classification of levels of evidence and degrees of recommendations of all recommendations, (3) validation of the consensus through two rounds of online surveys, and (4) manuscript composition. The consensus consists of 12 sections: Head and neck cancer staging, Histopathologic evaluation of head and neck cancer, Head and neck surgery-oral cavity, Clinical oncology-oral cavity, Head and neck surgery-oropharynx, Clinical oncology-oropharynx, Head and neck surgery-larynx, Head and neck surgery-larynx/hypopharynx, Clinical oncology-larynx/hypopharynx, Clinical oncology-recurrent and metastatic head and neck cancer, Head and neck surgery-reconstruction and rehabilitation, and Radiation therapy. The present consensus established 48 recommendations on HNSCC patient care considering the availability of resources and focusing on oncologic benefit. These recommendations could also be used to formulate strategies in other regions like Latin America countries.

Near-infrared imaging of head and neck squamous cell carcinoma using indocyanine green that targets the αvβ6 peptide

Significance

Head and neck squamous cell carcinoma (HNSCC) has a particularly poor prognosis. Improving the surgical resection boundary, reducing local recurrence, and ultimately ameliorating the overall survival rate are the treatment goals.

Aim

To obtain a complete surgical resection (R0 resection), we investigated the use of a fluorescent imaging probe that targets the integrin subtype α v β 6 , which is upregulated in many kinds of epithelial cancer, using animal models.

Approach

α v β 6 expression was detected using polymerase chain reaction (PCR) and immunoprotein blotting of human tissues for malignancy. Protein expression localization was observed. α v β 6 and epidermal growth factor receptor (EGFR) were quantified by PCR and immunoprotein blotting, and the biosafety of targeting the α v β 6 probe material was examined using Cell Counting Kit-8 assays. Indocyanine green (ICG) was used as a control to determine the localization of the probe at the cellular level. In vivo animal experiments were conducted through tail vein injections to evaluate the probe's imaging effect and to confirm its targeting in tissue sections.

Results

α v β 6 expression was higher than EGFR expression in HNSCC, and the probe showed good targeting in in vivo and in vitro experiments with a good safety profile.

Conclusions

The ICG-α v β 6 peptide probe is an exceptional and sensitive imaging tool for HNSCC that can distinguish among tumor, normal, and inflammatory tissues.

Development and validation of a cadaveric porcine Pseudotumor model for Oral Cancer biopsy and resection training

OBJECTIVE

The gold standard of oral cancer (OC) treatment is diagnostic confirmation by biopsy followed by surgical treatment. However, studies have shown that dentists have difficulty performing biopsies, dental students lack knowledge about OC, and surgeons do not always maintain a safe margin during tumor resection. To address this, biopsies and resections could be trained under realistic conditions outside the patient. The aim of this study was to develop and to validate a porcine pseudotumor model of the tongue.

METHODS

An interdisciplinary team reflecting various specialties involved in the oncological treatment of head and neck oncology developed a porcine pseudotumor model of the tongue in which biopsies and resections can be practiced. The refined model was validated in a final trial of 10 participants who each resected four pseudotumors on a tongue, resulting in a total of 40 resected pseudotumors. The participants (7 residents and 3 specialists) had an experience in OC treatment ranging from 0.5 to 27 years. Resection margins (minimum and maximum) were assessed macroscopically and compared beside self-assessed margins and resection time between residents and specialists. Furthermore, the model was evaluated using Likert-type questions on haptic and radiological fidelity, its usefulness as a training model, as well as its imageability using CT and ultrasound.

RESULTS

The model haptically resembles OC (3.0 ± 0.5; 4-point Likert scale), can be visualized with medical imaging and macroscopically evaluated immediately after resection providing feedback. Although, participants (3.2 ± 0.4) tended to agree that they had resected the pseudotumor with an ideal safety margin (10 mm), the mean minimum resection margin was insufficient at 4.2 ± 1.2 mm (mean ± SD), comparable to reported margins in literature. Simultaneously, a maximum resection margin of 18.4 ± 6.1 mm was measured, indicating partial over-resection. Although specialists were faster at resection (p < 0.001), this had no effect on margins (p = 0.114). Overall, the model was well received by the participants, and they could see it being implemented in training (3.7 ± 0.5).

CONCLUSION

The model, which is cost-effective, cryopreservable, and provides a risk-free training environment, is ideal for training in OC biopsy and resection and could be incorporated into dental, medical, or oncologic surgery curricula. Future studies should evaluate the long-term training effects using this model and its potential impact on improving patient outcomes.

Virtual tumor mapping and margin control with 3-D planning and navigation

Computer technology-based treatment approaches like intraoperative navigation and intensity-modulated radiation therapy have become important components of state of the art head and neck cancer treatment. Multidirectional exchange of virtual three-dimensional patient data via an interdisciplinary platform allows all medical specialists involved in the patients treatment to take full advantage of these technologies. This review article gives an overview of current technologies and future directions regarding treatment approaches that are based on a virtual, three-dimensional patient specific dataset: storage and exchange of spatial information acquired via intraoperative navigation allow for a highly precise frozen section procedure. In the postoperative setting, virtual reconstruction of the tumor resection surface provides the basis for improved radiation therapy planning and virtual reconstruction of the tumor with integration of molecular findings creates a valuable tool for postoperative treatment and follow-up. These refinements of established treatment components and novel approaches have the potential to make a major contribution to improving the outcome in head and neck cancer patients.

The art of specimen orientation: Two-dimensional maps for oropharynx squamous cell carcinoma

The goal of surgical treatment for oropharynx squamous cell carcinoma (SCCa) is resection to negative margins. Current methods of orienting resection specimens often do not give a comprehensive view, especially in oropharynx SCCa where specimens can lack anatomic landmarks. We created standardized two-dimensional maps of oropharynx anatomy drawn to scale to improve communication between surgeons and pathologists. Notes regarding surgery including anatomic landmarks, areas of concern, additional margins, and relevant clinical information were added to the map. The maps guided pathology work-up, and the pathologist could communicate details back to the surgeon on how the specimen was sectioned or locations of microscopic foci to direct future treatment and clinical monitoring. The use of two-dimensional maps for oropharynx SCCa specimens offers a standardized solution to address the challenges of anatomic orientation. These maps summarized key pathological information, preserved clinical details from the specimens, and guided multidisciplinary conferences when planning adjuvant treatment.

AI-Based Detection of Oral Squamous Cell Carcinoma with Raman Histology

Stimulated Raman Histology (SRH) employs the stimulated Raman scattering (SRS) of photons at biomolecules in tissue samples to generate histological images. Subsequent pathological analysis allows for an intraoperative evaluation without the need for sectioning and staining. The objective of this study was to investigate a deep learning-based classification of oral squamous cell carcinoma (OSCC) and the sub-classification of non-malignant tissue types, as well as to compare the performances of the classifier between SRS and SRH images. Raman shifts were measured at wavenumbers k1 = 2845 cm-1 and k2 = 2930 cm-1. SRS images were transformed into SRH images resembling traditional H&E-stained frozen sections. The annotation of 6 tissue types was performed on images obtained from 80 tissue samples from eight OSCC patients. A VGG19-based convolutional neural network was then trained on 64 SRS images (and corresponding SRH images) and tested on 16. A balanced accuracy of 0.90 (0.87 for SRH images) and F1-scores of 0.91 (0.91 for SRH) for stroma, 0.98 (0.96 for SRH) for adipose tissue, 0.90 (0.87 for SRH) for squamous epithelium, 0.92 (0.76 for SRH) for muscle, 0.87 (0.90 for SRH) for glandular tissue, and 0.88 (0.87 for SRH) for tumor were achieved. The results of this study demonstrate the suitability of deep learning for the intraoperative identification of tissue types directly on SRS and SRH images.

5-Aminolevulinic Acid Fluorescence-Guided Surgery in Head and Neck Squamous Cell Carcinoma

OBJECTIVES

To determine the utility of 5-aminolevulinic acid (5-ALA) fluorescence for resection of head and neck carcinoma.

METHODS

In this prospective pilot trial, 5-ALA was administered as an oral suspension 3-5 h prior to induction of anesthesia for resection of head and neck squamous cell carcinoma (HNSCC). Following resection, 405 nm blue light was applied, and fluorescence of the tumor as well as the surgical bed was recorded. Specimen fluorescence intensity was graded categorically as none (score = 0), mild (1), moderate (2), or robust (3) by the operating surgeon intraoperatively and corroborated with final pathologic diagnosis.

RESULTS

Seven patients underwent resection with 5-ALA. Five (83%) were male with an age range of 33-82 years (mean = 60). Sites included nasal cavity (n = 3), oral cavity (n = 3), and the larynx (n = 1). All specimens demonstrated robust fluorescence when 5-ALA was administered 3-5 h preoperatively. 5-ALA fluorescence predicted the presence of perineural invasion, a positive margin, and metastatic lymphadenopathy. Two patients had acute photosensitivity reactions, and one patient had a temporary elevation of hepatic enzymes.

CONCLUSIONS

5-ALA induces robust intraoperative fluorescence of HNSCC, capable of demonstrating a positive margin, perineural invasion, and metastatic nodal disease. Although no conclusions are there about the safety of this drug in the head and neck cancer population, our study parallels the extensive safety data in the neurosurgical literature. Future applications may include intraoperative assessment of margin status, diagnostic accuracy, and impacts on survival.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:741-748, 2024.

Cutting guides in mandibular tumor ablation: Are we as accurate as we think?

Purpose

Tumor margin status is critical in local tumor recurrence and is a significant prognostic factor in head and neck cancer survival. With the introduction of computer-assisted surgical planning, one of the main challenges is the accurate positioning of the surgical cutting guide but there is limited evidence of the accuracy of the 3D cutting guides in mimicking virtually planned osteotomy. This study evaluates the accuracy of osteotomy lines produced by 3D-printed cutting guides and assesses the overall accuracy of mandibular reconstruction.

Material and Methods

The pre and postoperative 3D models were aligned using an automated surface registration feature based on the iterative closest point algorithm. The differences in osteotomy line deviation, linear and angle measurements, and 3D volume quantification of the pre and post models were measured.

Results

We included 14 patients (8 men and 6 women with ages ranging from 13 to 75 years) with a segmental mandibular resection who met all of the inclusion criteria. The smallest defect size was 4.4 cm, the largest defect was 12.2 cm, and the average was 7.30 cm +/- 2.80 cm. The average deviation between virtually planned osteotomy and actual surgical osteotomy was 1.52 +/-1.02 mm. No covariates were associated with increased inaccuracy of the 3D-printed cutting guides.

Conclusion

The finding of this study suggests that virtual surgical planning is an unambiguous paradigm shift in the predictability of the surgical plan and achievement of the reconstruction goals. The 3D-printed cutting guides are a very accurate and reliable tool in translating virtual ablation plans to an actual surgical resection margin.

Value and role of surgical margins in transoral laser microsurgery of the larynx, literature review and clinical considerations

PURPOSE

There is no agreement on the most appropriate post-operative pathway for the management of positive margins after laser cordectomy for early stage glottic tumours (T1-2N0M0). This literature review and meta-analysis aim to evaluate the post-operative treatment with the best oncological results among follow-up, radiotherapy (RT) and surgical second look. The parameters utilized were incidence of recurrence, overall (OS), disease-specific (DSS) and disease-free (DFS) survival and larynx preservation (LP).

METHODS

The articles were found through a string typed into PubMed from 2007 to 2022. The studies with detailed oncological results were selected according to inclusion criteria, and then the meta-analysis was carried out.

RESULTS

Sixteen studies met the inclusion criteria for 2808 patients. The positive margin was found in 748 patients (26.6%), of which 416 were referred to follow-up, 89 to RT and 242 to a surgical second look. A false positive margin was found in 58/104 patients (56%). The recurrence rate in patients with positive margins was significantly higher (p = 0.003). In OS, DSS, DFS and LP, the odds ratio (OR) value was always greater than 1, assessing the role of the positive margin as a risk factor.

CONCLUSIONS

Prospective studies will be necessary to establish the role of positive margin as a prognostic factor. A surgical second look in case of positive margin seems to be the best option for the patient in terms of lower risk of recurrence and better oncological results. Better collaboration between surgeon and pathologist would be desirable to limit the real and false positive margins.

Improved intraoperative identification of close margins in oral squamous cell carcinoma resections using a dual aperture fluorescence ratio approach: first in-human results

Significance

Surgical excision is the main treatment for solid tumors in oral squamous cell carcinomas, where wide local excision (achieving a healthy tissue margin of > 5    mm around the excised tumor) is the goal as it results in reduced local recurrence rates and improved overall survival.

Aim

No clinical methods are available to assess the complete surgical margin intraoperatively while the patient is still on the operating table; and while recent intraoperative back-bench fluorescence-guided surgery approaches have shown promise for detecting "positive" inadequate margins (< 1    mm ), they have had limited success in the detection of "close" inadequate margins (1 to 5 mm). Here, a dual aperture fluorescence ratio (dAFR) approach was evaluated as a means of improving detection of close margins.

Approach

The approach was evaluated on surgical specimens from patients who were administered a tumor-specific fluorescent imaging agent (cetuximab-800CW) prior to surgery. The dAFR approach was compared directly against standard wide-field fluorescence imaging and pathology measurements of margin thickness in specimens from three patients and a total of 12 margin locations (1 positive, 5 close, and 6 clear margins).

Results

The area under the receiver operating characteristic curve, representing the ability to detect close compared to clear margins (> 5    mm ) was found to be 1.0 and 0.57 for dAFR and sAF, respectively. Improvements in dAFR were found to be statistically significant (p < 0.02 ).

Conclusions

These results provide evidence that the dAFR approach potentially improves detection of close surgical margins.

Intraoperative Assessment of Resection Margin in Oral Cancer: The Potential Role of Spectroscopy

In parallel with the increasing number of oncological cases, the need for faster and more efficient diagnostic tools has also appeared. Different diagnostic approaches are available, such as radiological imaging or histological staining methods, but these do not provide adequate information regarding the resection margin, intraoperatively, or are time consuming. The purpose of this review is to summarize the current knowledge on spectrometric diagnostic modalities suitable for intraoperative use, with an emphasis on their relevance in the management of oral cancer. The literature agrees on the sensitivity, specificity, and accuracy of spectrometric diagnostic modalities, but further long-term prospective, multicentric clinical studies are needed, which may standardize the intraoperative assessment of the resection margin and the use of real-time spectroscopic approaches.

Clinical Experience with Autofluorescence Guided Oral Squamous Cell Carcinoma Surgery

In our study, the effect of the use of autofluorescence (Visually Enhanced Lesion Scope-VELscope) on increasing the success rate of surgical treatment in oral squamous carcinoma (OSCC) was investigated. Our hypothesis was tested on a group of 122 patients suffering from OSCC, randomized into a study and a control group enrolled in our study after meeting the inclusion criteria. The preoperative checkup via VELscope, accompanied by the marking of the range of a loss of fluorescence in the study group, was performed before the surgery. We developed a unique mucosal tattoo marking technique for this purpose. The histopathological results after surgical treatment, i.e., the margin status, were then compared. In the study group, we achieved pathological free margin (pFM) in 55 patients, pathological close margin (pCM) in 6 cases, and we encountered no cases of pathological positive margin (pPM) in the mucosal layer. In comparison, the control group results revealed pPM in 7 cases, pCM in 14 cases, and pFM in 40 of all cases in the mucosal layer. This study demonstrated that preoperative autofluorescence assessment of the mucosal surroundings of OSCC increased the ability to achieve pFM resection 4.8 times in terms of lateral margins.

The impact of undergoing surgical margin evaluation during endoscopic surgery for early-stage laryngeal squamous cell carcinoma

BACKGROUND

The impact of evaluating versus not evaluating surgical margins for early-stage laryngeal squamous cell carcinoma (LSCC) has not been evaluated.

METHODS

Overall survival was compared between patients who underwent endoscopic surgery for cT1-2, N0, M0 LSCC and had surgical margins evaluated versus not evaluated versus unevaluable in the National Cancer Database (2010-2019) using multivariable-adjusted Cox proportional hazards analyses.

RESULTS

7597 patients met study eligibility criteria. 4123 (54.3%) patients underwent margin evaluation, 1631 (21.5%) did not undergo margin evaluation, and 1843 (24.3%) had unevaluable margins. Patients undergoing margin evaluation had better overall survival than patients who did not undergo margin evaluation (HR: 0.88, 95% CI: 0.78-1.00, p = 0.044) and patients with unevaluable margins (HR: 0.88, 95% CI: 0.78-0.98, p = 0.021). Patients undergoing margin evaluation received significantly less adjuvant radiation.

CONCLUSIONS

Surgical margin evaluation is an important prognostic factor for patients receiving endoscopic surgery for early-stage LSCC and should be conducted whenever possible.

An Oral Microbial Biomarker for Early Detection of Recurrence of Oral Squamous Cell Carcinoma

Changes in the oral microbiome are associated with oral squamous cell carcinoma (OSCC). Oral microbe-derived signatures have been utilized as markers of OSCC. However, the structure of the oral microbiome during OSCC recurrence and biomarkers for the prediction of OSCC recurrence remains unknown. To identify OSCC recurrence-associated microbial biomarkers for the prediction of OSCC recurrence, we performed 16S rRNA amplicon sequencing on 54 oral swab samples from OSCC patients. Differences in bacterial compositions were observed in patients with vs without recurrence. We found that Granulicatella, Peptostreptococcus, Campylobacter, Porphyromonas, Oribacterium, Actinomyces, Corynebacterium, Capnocytophaga, and Dialister were enriched in OSCC recurrence. Functional analysis of the oral microbiome showed altered functions associated with OSCC recurrence compared with nonrecurrence. A random forest prediction model was constructed with five microbial signatures including Leptotrichia trevisanii, Capnocytophaga sputigena, Capnocytophaga, Cardiobacterium, and Olsenella to discriminate OSCC recurrence from original OSCC (accuracy = 0.963). Moreover, we validated the prediction model in another independent cohort (46 OSCC patients), achieving an accuracy of 0.761. We compared the accuracy of the prediction of OSCC recurrence between the five microbial signatures and two clinicopathological parameters, including resection margin and lymph node counts. The results predicted by the model with five microbial signatures showed a higher accuracy than those based on the clinical outcomes from the two clinicopathological parameters. This study demonstrated the validity of using recurrence-related microbial biomarkers, a noninvasive and effective method for the prediction of OSCC recurrence. Our findings may contribute to the prognosis and treatment of OSCC recurrence.

Surgical margin status and role of adjuvant therapy in human papillomavirus-positive oropharyngeal cancer

BACKGROUND

We analyzed the difference in treatment results according to safety margin range and studied the role of adjuvant therapy in patients with human papillomavirus-positive (HPV+) oropharyngeal squamous cell carcinoma (OPSCC).

MATERIALS AND METHODS

A total of 279 patients with HPV+ OPSCC were included in this study.

RESULTS

Surgical margin and T classification were significant prognostic factors related to death. The difference in locoregional recurrence was analyzed by dividing the safety margin into groups of <1, 1-5, and >5 mm. There was no significant difference in local-regional recurrence for T1-T2 lesions between the three groups. Adjuvant therapy can significantly reduce disease recurrence in HPV+ OPSCC patients with risk factors.

CONCLUSIONS

In T1-T2 lesions without other risk factors, even with a safety margin ≥1 mm, adjuvant therapy can potentially be omitted. Adjuvant therapy can significantly reduce disease recurrence in HPV+ OPSCC patients with risk factors.

Significance of Worst Pattern of Invasion-5 in Early-Stage Oral Cavity Squamous Cell Carcinoma

BACKGROUND

There is an ongoing need to identify pathologic prognosticators in early-stage oral cavity squamous cell carcinoma (OCSCC) to aid selection of patients who may benefit from adjuvant treatment. The objective of this study was to evaluate the prognostic ability of worst pattern of invasion-5 (WPOI-5) defined by the presence of satellite nodules, extratumoural perineural invasion (PNI) and/or extratumoural lymphovascular space invasion (LVI) in low-stage, node negative OCSCC.

METHODS

This was a retrospective study of 160 patients with T1/T2N0 tumours staged using TNM7 treated surgically. Histology of the primary tumour was re-reviewed as appropriate to assess for the presence of WPOI-5 parameters. Univariate and multivariate analysis assessing impact of pathological features on survival outcomes was performed.

RESULTS

On univariate analysis, WPOI-5 and its 3 constituent components of satellite nodules, extratumoural PNI and extratumoural LVI were all significantly associated with disease-specific survival (DSS) and overall survival (OS). On multivariate analysis, satellite nodules (odds ratio 6.61, 95% CI 2.83-15.44, p < 0.0001) and extratumoural LVI (odds ratio 9.97, 95% CI 2.19-45.35, p = 0.003) were independently associated with OS. Postoperative radiotherapy (odds ratio 0.40, 95% CI 0.19-0.87, p = 0.02) and non-tongue subsite (odds ratio 3.03, 95% CI 1.70-5.39, p = 0.0002) were also significantly associated with OS on multivariate analysis.

CONCLUSION

Satellite nodules and extratumoural LVI correlated significantly with survival outcomes in our early-stage OSCC cohort. Further study is required to investigate the benefit of adjuvant treatment in these cases and to ascertain if WPOI-5 parameters including satellite nodules should be mandatory reporting data elements.

Emerging clinical applications in oncology for non-invasive multi- and hyperspectral imaging of cell and tissue autofluorescence

Hyperspectral and multispectral imaging of cell and tissue autofluorescence is an emerging technology in which fluorescence imaging is applied to biological materials across multiple spectral channels. This produces a stack of images where each matched pixel contains information about the sample's spectral properties at that location. This allows precise collection of molecularly specific data from a broad range of native fluorophores. Importantly, complex information, directly reflective of biological status, is collected without staining and tissues can be characterised in situ, without biopsy. For oncology, this can spare the collection of biopsies from sensitive regions and enable accurate tumour mapping. For in vivo tumour analysis, the greatest focus has been on oral cancer, whereas for ex vivo assessment head-and-neck cancers along with colon cancer have been the most studied, followed by oral and eye cancer. This review details the scope and progress of research undertaken towards clinical translation in oncology.

Narrow-Band Imaging in Transoral Laser Surgery for Early Glottic Cancer: A Randomized Controlled Trial

OBJECTIVE

Assessing whether the additional use of narrow-band imaging (NBI) in transoral laser surgery (TOLS) for early laryngeal cancer improves clinical outcomes.

STUDY DESIGN

Randomized controlled trial, performed between September 2015 and November 2022.

SETTING

A tertiary referral hospital in The Netherlands.

METHODS

TOLS was carried out in 113 patients. The procedure was performed with white light imaging (WLI, n = 56) alone, or combined with NBI (n = 57). Patients received frequent follow-up laryngoscopy. Resection margin status, recurrence rate, and recurrence-free survival at 12 months, 18 months, and after study termination (maximum 86 months) were analyzed.

RESULTS

Thirty-one cases in the WLI group had a positive resection margin, versus 16 in the NBI group (p = .002). After 12 months, the recurrence-free survival was 92%: 87% for WLI versus 96% for NBI, p = .07. The recurrence rate was 7/56 (13%) for WLI, versus 2/57 (4%) for NBI, p = .09. After 18 months, the recurrence-free survival was 84% for WLI versus 96% for NBI, p = .02. The recurrence rate was 9/56 (16%) for WLI, versus 2/57 (4%) for NBI, p = .02. After study termination, the recurrence-free survival was 71% for WLI versus 83% for the NBI group (p = .08). The recurrence rate was 16/56 for WLI, versus 10/57 for NBI (p = .16).

CONCLUSION

The additional use of NBI during TOLS significantly decreased the number of positive resection margins. Although not statistically significant at all time points, patients treated with NBI-supported TOLS showed a lower recurrence rate and better recurrence-free survival. Further studies in larger patient groups are needed to confirm these results.

Pre-resection Intraoperative Core Biopsies in Oral Tongue Cancer-A Pilot Study

OBJECTIVE

To assess a novel intraoperative core biopsy technique to provide enhanced guidance in partial glossectomies.

METHODS

All patients diagnosed with squamous cell carcinoma of the oral tongue were eligible for study participation. Following anesthesia, the planned resection and three points midway between the gross tumor and the intended ablation were marked. A core biopsy was performed with a needle spring on each point and sent for frozen sections. The initially planned resection was executed if the cores returned free of tumor. In case of a positive core biopsy, a new 1-1.5 cm margin was marked around that point. The main outcome measure was the closest final margin diameter, especially the deep ones. Other outcome measures were the core biopsies' sensitivity, specificity, and negative predictive value. Complications were recorded.

RESULTS

The final margins of 10 patients undergoing intraoperative core biopsies and 20 matched controls were analyzed. One patient had two positive cores and final negative margins after modifying the resection accordingly. Another patient had a positive biopsy diagnosed only on final pathology, and one close final margin. Patients that were operated with the new technique had larger margins compared to the controls: median (interquartile range) closest margin 5.95 (3.97; 9.63) mm versus 4 (2.25; 5) mm (p = 0.074) and median deep margin 8.6 (6.16; 10) mm versus 5 (3;10) mm (p = 0.411), respectively. There were no complications.

CONCLUSION

A novel pre-resection intraoperative biopsy technique is presented. Core biopsies taken during glossectomies have the potential to prevent inadequate margins.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:2232-2236, 2023.

CRM1 expression: association with high prognostic value in laryngeal cancer

BACKGROUND

Laryngeal cancer is a very common malignant tumor of the head and neck. While laryngeal cancer does not show any obvious early symptoms, it tends to have a poor prognosis in advanced clinical stages. Chromosome region maintenance 1 (CRM1) mediates the nuclear export of some RNAs, major and tumor suppressor proteins and has been associated with the pathogenesis of many tumors. However, the clinicopathological significance of CRM1 gene expression in laryngeal cancer has not been clarified yet. Therefore, this study aims to detect the expression of CRM1 in laryngeal cancer and to investigate its relationship with clinicopathological parameters and prognosis.

METHODS

CRM1 expression in matched tumor and normal tissues obtained from 43 laryngeal cancer patients were evaluated intracellular for protein and mRNA levels by immunohistochemical staining (IHC), western-blot, and quantitative real-time RT-PCR (qRT-PCR), respectively.

RESULTS

IHC, western-blot, and qRT-PCR analyses showed that CRM1 expression was significantly increased in laryngeal cancer tissue compared to normal tissue. Increased expression of CRM1 has been associated with poor prognostic clinicopathological features, including advanced tumor stage, increased tumor invasion, larger tumor size, positive lymph node metastasis, distant metastasis, and invasive histological type by IHC, western-blot, and qRT-PCR. Kaplan-Meier survival analysis showed that patients with high expression of CRM1 exhibited lower overall survival compared to those with low expression (Log-rank = 7.16, p = 0.007). According to the The Cancer Genome Atlas (TCGA) datasets, elevated CRM1 expression in head and neck cancer including cases of squamous cell laryngeal origin is associated with advanced tumor stage and histological grade (p > 0.05, for all).

DISCUSSION

Consequently, CRM1 plays an important role in laryngeal cancer and may serve as an indicator and prognostic factor for poor overall survival in laryngeal cancer patients.

Eugene Nicholas Myers' Lecture on Head and Neck Cancer, 2020: The Surgeon as a Prognostic Factor in Head and Neck Cancer Patients Undergoing Surgery

This paper is a transcript of the 29 th Eugene N. Myers, MD International Lecture on Head and Neck Cancer presented at the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) in 2020. By the end of the 19 th century, the survival rate in treated patients was 10%. With the improvements in surgical techniques, currently, about two thirds of patients survive for > 5 years. Teamwork and progress in surgical reconstruction have led to advancements in ablative surgery; the associated adjuvant treatments have further improved the prognosis in the last 30 years. However, prospective trials are lacking; most of the accumulated knowledge is based on retrospective series and some real-world data analyses. Current knowledge on prognostic factors plays a central role in an efficient treatment decision-making process. Although the influence of most tumor- and patient-related prognostic factors in head and neck cancer cannot be changed by medical interventions, some environmental factors-including treatment, decision-making, and quality-can be modified. Ideally, treatment strategy decisions should be taken in dedicated multidisciplinary team meetings. However, evidence suggests that surgeons and hospital volume and specialization play major roles in patient survival after initial or salvage head and neck cancer treatment. The metrics of surgical quality assurance (surgical margins and nodal yield) in neck dissection have a significant impact on survival in head and neck cancer patients and can be influenced by the surgeon's expertise. Strategies proposed to improve surgical quality include continuous performance measurement, feedback, and dissemination of best practice measures.

Navigation-guided resection of locally advanced midface malignancies. Does it improve the safety of oncologic resection?

INTRODUCTION

Treatment of malignant midface tumors is a surgical challenge with an increased difficulty to obtain free surgical margins. The computer assisted surgery (CAS) and intraoperative navigation (ION) can be very helpful in complex midface resections. The main objective of this paper is to evaluate if the ION could improve the rate of free surgical margins in locally advanced midface malignancies.

MATERIALS AND METHODS

A retrospective cohort study was performed including 40 patients with a locally advanced malignant midface tumor (T4a/b) surgically treated from September 2016 to September 2022. Patients were divided in two groups, a control group included 20 patients operated on without ION and the study group included 20 patients treated with Navigation assisted surgery. A systematic analysis was performed comparing surgical margins in both groups.

RESULTS

Squamous cell carcinoma was the most common histological type. Oral cavity was the most common primary location. Overall, considering each specimen as an hexahedrium, 240 surgical margins were analyzed. 15 out of 120 margins analyzed in the navigation group (12.5 %) were positive while 30 out of 120 margins analyzed in control group (25 %) were affected (p 0.013). Concerning margin location, the ION group showed less involvement of the upper surface of specimen than in control group (p 0.048).

CONCLUSION

Navigation Assisted Surgery seems to improve the rate of free surgical margins in patients with locally advanced midface malignancies, specially concerning involvement of the superior margin. Further studies are recommended to corroborate these results and its potential influence in survival rates.

Frozen Section Analysis in Head and Neck Surgical Pathology: A Narrative Review of the Past, Present, and Future of Intraoperative Pathologic Consultation

Frozen section has remained the diagnostic gold standard for intraoperative pathological evaluation of surgical margins for head and neck specimens. While achieving tumor-free margins is of utmost importance to all head and neck surgeons, in practice, there are numerous debates and a lack of standardization for the role and method of intraoperative pathologic consultation. This review serves as a summary guide to the historical and contemporary practice of frozen section analysis and margin mapping in head and neck cancer. In addition, this review discusses current challenges in head and neck surgical pathology, and introduces 3D scanning as a groundbreaking technology to bypass many of the pitfalls in the current frozen section workflow. The ultimate goal for all head and neck pathologists and surgeons should be to modernize practices and take advantage of new technology, such as virtual 3D specimen mapping techniques, that improves the workflow for intraoperative frozen section analysis.

Diagnostic accuracy of intraoperative margin assessment techniques in surgery for head and neck squamous cell carcinoma: A meta-analysis

BACKGROUND

Positive margins following head and neck squamous cell carcinoma (HNSCC) surgery lead to significant morbidity and mortality. Existing Intraoperative Margin Assessment (IMA) techniques are not widely used due to limitations in sampling technique, time constraints and resource requirements. We performed a meta-analysis of the diagnostic performance of existing IMA techniques in HNSCC, providing a benchmark against which emerging techniques may be judged.

METHODS

The study was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Studies were included if they reported diagnostic metrics of techniques used during HNSCC surgery, compared with permanent histopathology. Screening, manuscript review and data extraction was performed by multiple independent observers. Pooled sensitivity and specificity were estimated using the bivariate random effects model.

RESULTS

From an initial 2344 references, 35 studies were included for meta-analysis. Sensitivity (Sens), specificity (Spec), diagnostic odds ratio (DOR) and area under the receiver operating characteristic curve (AUROC) were calculated for each group (n, Sens, Spec, DOR, AUROC): frozen section = 13, 0.798, 0.991, 309.8, 0.976; tumour-targeted fluorescence (TTF) = 5, 0.957, 0.827, 66.4, 0.944; optical techniques = 10, 0.919, 0.855, 58.9, 0.925; touch imprint cytology = 3, 0.925, 0.988, 51.1, 0.919; topical staining = 4, 0.918, 0.759, 16.4, 0.833.

CONCLUSIONS

Frozen section and TTF had the best diagnostic performance. Frozen section is limited by sampling error. TTF shows promise but involves administration of a systemic agent. Neither is currently in widespread clinical use. Emerging techniques must demonstrate competitive diagnostic accuracy whilst allowing rapid, reliable, cost-effective results.

Positive Deep Initial Incision Margin Affects Outcomes in TORS for HPV+ Oropharynx Cancer

OBJECTIVE

Evaluate the effect of initial incision margins (IIM) on clinical outcomes after transoral robotic surgery (TORS) for human papillomavirus positive (HPV+) squamous cell cancers of the oropharynx (OPSCC).

METHODS

Retrospective chart review of patients undergoing TORS for HPV+ OPSCC from 2007 to 2015 was performed. Overall survival (OS), disease-specific survival (DSS), recurrence, and metastases were evaluated in the context of pathology, IIM, final margins, adjuvant therapy, and patient characteristics.

RESULTS

Ninety-five patients with HPV+ OPSCC undergoing primary surgery were identified. 88% of these patients had no evidence of disease at the conclusion of the study (average follow-up 45 months). Twenty were identified that had true positive IIM and 16 had very close IIM, with the remainder demonstrating widely negative margins. Tumor very close to or involving the deep margin but not a mucosal margin was associated with a higher risk of recurrence. Perineural invasion and lymphovascular invasion were associated with positive IIM. Positive or very close IIM on the deep margin was found to impact DSS and recurrence.

CONCLUSION

Obtaining negative IIM while performing TORS for HPV+ OPSCC is a modifiable factor that affects recurrence and DSS. Larger surgical margins should be considered in patients with perineural invasion or whose tumor abuts the initial deep margin.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:1132-1137, 2023.

Clinicopathological characteristics, treatment and prognosis of oral adenocarcinoma: a population-based study

OBJECTIVES

The aim of this study was to identify clinicopathologic features, treatment and prognosis of oral adenocarcinoma (OADC).

STUDY DESIGN

Retrospective cohort analysis.

SETTING

National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) program.

METHODS

Patients diagnosed with OADC between 2000 to 2018 were identified from the SEER database. Overall survival (OS) and disease-specific survival (DSS) were assessed using Kaplan-Meier analyses and Cox regression models.

RESULTS

There were 924 OADC and 37,500 oral squamous cell carcinoma (OSCC) patients identified. Patients with OADC were more significantly associated with younger age, female gender, well differentiation and early AJCC Clinical stage. The study revealed that patients with OADC had better 10-year OS and DSS than those with OSCC (OS: 69.3% vs 40.8%, P < 0.001; DSS: 83.6% vs 53.3%, P < 0.001). The survival advantage still persisted in multivariable analyses (OS: hazard ratio [HR] = 0.427, P < 0.001; DSS: HR = 0.320, P < 0.001). For OADC, multivariable analysis showed that advanced age, stage, and histologic grade were associated with worse OS and DSS, and surgery was associated with better OS and DSS.

CONCLUSIONS

OADC has a significantly better prognosis than OSCC, with better differentiation, and more early stage. Surgery was the preferred treatment, for patients with lymph node metastasis, radiotherapy may afford a survival benefit.

Tumor volume definitions in head and neck squamous cell carcinoma - Comparing PET/MRI and histopathology

BACKGROUND AND PURPOSE

In cancer treatment precise definition of the tumor volume is essential, but despite development in imaging modalities, this remains a challenge. Here, pathological tumor volumes from the surgical specimens were obtained and compared to tumor volumes defined from modern PET/MRI hybrid imaging. The purpose is to evaluate mismatch between the volumes defined from imaging and pathology was estimated and potential clinical impact.

METHODS AND MATERIALS

Twenty-five patients with head and neck squamous cell carcinoma were scanned on an integrated PET/MRI system prior to surgery. Three gross tumor volumes (GTVs) from the primary tumor site were delineated defined from MRI (GTV_MRI), PET (GTV_PET) and one by utilizing both anatomical images and clinical information (GTV_ONCO). Twenty-five primary tumor specimens were extracted en bloc, scanned with PET/MRI and co-registered to the patient images. Each specimen was sectioned in blocks, sliced and stained with haematoxylin and eosin. All slices were digitalized and tumor delineated by a head and neck pathologist. The pathological tumor areas in all slices were interpolated yielding a pathological 3D tumor volume (GTV_PATO). GTV_PATOwas compared with the imaging GTV's and potential mismatch was estimated.

RESULTS

Thirteen patients were included. The mean volume of GTV_ONCOwas larger than the GTV's defined from PET or MRI. The mean mismatch of the GTV_PATOcompared to the GTV_PET, GTV_MRIand GTV_ONCOwas 31.9 %, 54.5 % and 27.9 % respectively, and the entire GTV_PATO was only fully encompassed in GTV_ONCO in 1 of 13 patients. However, after the addition of a clinical 5 mm margin the GTV_PATO was fully encompassed in GTV_ONCO in 11 out of 13 patients.

CONCLUSIONS

Despite modern hybrid imaging modalities, a mismatch between imaging and pathological defined tumor volumes was observed in all patients.A 5 mm clinical margin was sufficient to ensure inclusion of the entire pathological volume in 11 out of 13 patients.

Facility volume and survival: Human papilloma virus positive oropharyngeal squamous cell carcinoma

BACKGROUND

To analyze the impact of facility volume on survival for human papilloma virus positive oropharyngeal squamous cell carcinoma (HPV+ OPSCC) patients.

METHODS

Patients treated for HPV+ OPSCC from 2010 to 2017 were queried from the National Cancer Database. Facilities of average annual case volume <50th percentile were categorized as low-volume (LV) and >95th percentile as high-volume (HV).

RESULTS

11,546 were included, with 10,305 patients (89.3 %) treated at LV and 1241 (10.7 %) at HV facilities. A greater proportion of cases involving resection of base of tongue and lingual tonsil were treated at HV (30.3 %) compared to LV (22.3 %) facilities (p < 0.001). Patients treated at a HV facility had greater percentage of clinical T4 (11.2 % vs. 8.6 %, p = 0.001) and N+ disease (90.5 % vs. 85.7 %, p < 0.001) patients. Survival analysis showed no statistically significant difference between five-year overall survival rates by facility volume (p = 0.388) for all patients. On multivariable analysis, facility volume was not associated with survival (HR: 0.968 [0.758-1.235], p = 0.791). These trends were found for both patients undergoing primary surgery or chemoradiotherapy.

CONCLUSION

Our data indicates that patients with HPV+ OPSCC do not experience a survival benefit with treatment at HV facility, suggesting these patients may be adequately treated at LV centers.

Intraoperative Imaging Techniques to Improve Surgical Resection Margins of Oropharyngeal Squamous Cell Cancer: A Comprehensive Review of Current Literature

Inadequate resection margins in head and neck squamous cell carcinoma surgery necessitate adjuvant therapies such as re-resection and radiotherapy with or without chemotherapy and imply increasing morbidity and worse prognosis. On the other hand, taking larger margins by extending the resection also leads to avoidable increased morbidity. Oropharyngeal squamous cell carcinomas (OPSCCs) are often difficult to access; resections are limited by anatomy and functionality and thus carry an increased risk for close or positive margins. Therefore, there is a need to improve intraoperative assessment of resection margins. Several intraoperative techniques are available, but these often lead to prolonged operative time and are only suitable for a subgroup of patients. In recent years, new diagnostic tools have been the subject of investigation. This study reviews the available literature on intraoperative techniques to improve resection margins for OPSCCs. A literature search was performed in Embase, PubMed, and Cochrane. Narrow band imaging (NBI), high-resolution microendoscopic imaging, confocal laser endomicroscopy, frozen section analysis (FSA), ultrasound (US), computed tomography scan (CT), (auto) fluorescence imaging (FI), and augmented reality (AR) have all been used for OPSCC. NBI, FSA, and US are most commonly used and increase the rate of negative margins. Other techniques will become available in the future, of which fluorescence imaging has high potential for use with OPSCC.

Metallic Artifact Reduction in Midfacial CT Scans Using Patient-Specific Polymer Implants Enhances Image Quality

Midfacial reconstruction after tumor resection surgery is commonly conducted by using autologous bone grafts or alloplastic implants. Titanium is the most frequently used osteosynthesis material in these cases but causes disturbing metallic artifacts in CT imaging. The purpose of this experimental study was to evaluate whether the use of midfacial polymer implants reduces metallic artifacts in CT imaging to improve image quality. Zygomatic titanium (n = 1) and polymer (n = 12) implants were successively implanted in a human skull specimen. Implants were analyzed for their effect on Hounsfield Unit values (streak artifacts) and virtual growth in CT images (blooming artifacts) as well as image quality. Multi-factorial ANOVA and Bonferroni's post hoc test were used. Titanium (173.7 HU; SD ± 5.1) and hydroxyapatite containing polymers (155.3 HU; SD ± 5.9) were associated with significantly more streak artifacts compared to all other polymer materials. There was no significant difference in blooming artifacts between materials. The metallic artifact reduction algorithm showed no significant difference. Image quality was slightly better for polymer implants compared to titanium. Personalized polymer implants for midfacial reconstruction significantly reduce metallic artifacts in CT imaging which improves image quality. Hence, postoperative radiation therapy planning and radiological tumor aftercare around the implants are facilitated.

A c-MET-Targeted Topical Fluorescent Probe cMBP-ICG Improves Oral Squamous Cell Carcinoma Detection in Humans

INTRODUCTION

The postoperative survival of oral squamous cell carcinoma (SCC) relies on precise detection and complete resection of original tumors. The mucosal extension of the tumor is evaluated visually during surgery, but small and flat foci are difficult to detect. Real-time fluorescence imaging may improve detection of tumor margins.

MATERIALS AND METHODS

In the current study, a peptide-based near-infrared (NIR) fluorescence dye, c-MET-binding peptide-indocyanine green (cMBP-ICG), which specifically targets tumor via c-MET binding, was synthetized. A prospective pilot clinical trial then was conducted with oral SCC patients and intraoperatively to assess the feasibility of cMBP-ICG used to detect tumors margins. Fluorescence was histologically correlated to determine sensitivity and specificity.

RESULTS

The immunohistochemistry (IHC) results demonstrated increased c-Met expression in oral SCC compared with normal mucosa. Tumor-to-background ratios ranged from 2.71 ± 0.7 to 3.11 ± 1.2 in different concentration groups. From 10 patients with oral SCC, 60 specimens were collected from tumor margins. The sensitivity and specificity of discriminative value derived from cMBP-ICG application in humans were respectively 100% and 75%.

CONCLUSIONS

Topical application of cMBP-ICG is feasible and safe for optimizing intraoperative visualization and tumor margin detection in oral SCC patients, which could clinically increase the probability of complete resections and improve oncologic outcomes.

The computer-aided design margin: Ex vivo 3D specimen mapping to improve communication between surgeons and pathologists

BACKGROUND

Numerous challenges exist in determining surgical margin status. Communication between surgeons and pathologists is crucial for specimen orientation and accurate margin assessment.

METHODS

A prospective study to determine feasibility of incorporating three-dimensional (3D) scanning into surgical pathology workflow was performed. A structured-light 3D scanner captured the photorealistic surface topography of fresh surgical specimens. Computer-aided design (CAD) software was used to document sites of margin sampling and sectioning. Surveys were distributed among faculty and staff stakeholders to assess feasibility.

RESULTS

A series of 40 cases were 3D-scanned. Median image acquisition time was 8 min. The majority of respondents agreed that the experimental 3D system helped achieve clearer communication. 3D specimen maps assisted in the communication of a focally positive or close margin in 4 of 17 cases.

CONCLUSIONS

Routine 3D scanning and specimen mapping is feasible and represents an innovative approach to intraoperative and final pathology documentation, margin analysis, and surgeon-pathologist communication.

Applicability of autofluorescence and fluorescent probes in the trans-surgical of oral carcinomas: A systematic review

Oral cancer represents an important health problem, as it is the sixth most common type of cancer in the world and is associated with high rates of morbidity and mortality. The treatment considered the gold standard for this type of tumor is surgical resection with negative margins, with a distance of at least 5 mm from the tumor. This procedure is strongly associated with local control and disease-specific survival, however, in many cases, large amounts of healthy tissue are removed, resulting in surgical defects, compromising various functions and directly affecting the individual's quality of life. From this perspective, this systematic review aimed to evaluate the use of autofluorescence and fluorescent probes as potential adjuvant techniques to facilitate the delineation of surgical margins for oral cancers. A comprehensive search was performed in Pubmed, Scopus, Web of Science, LIVIVO, Embase, ProQuest Open Access Dissertations & Theses, Open Access Theses and Dissertations, and DART Europe databases, where 1948 articles were found. After the different stages of critical evaluation, 15 articles were selected, eligible for the inclusion criteria. Of these, 7 articles used autofluorescence, 7 used fluorescent probes and 1 article used both methods. As for autofluorescence, the most used device was the VELScope, and indocyanine green was the most used probe. Compared to histopathology, autofluorescence did not obtain significant and/or superiors results. In contrast to fluorescent probes that, most articles showed a good performance of margins during surgical resection, making them a promising alternative. However, it is still necessary to carry out the analysis of more articles, with more significant samples and sensitivity and specificity data to qualify the results.

Surgical Extent for Oral Cancer: Emphasis on a Cut-Off Value for the Resection Margin Status: A Narrative Literature Review

The optimal cut-off point of the resection margin was recently debated in oral cancer. To evaluate the current evidence of the dynamic criteria of the resection margin, a review of the available literature was performed. Studies were sourced from PubMed and EMBASE by searching for the keywords "mouth neoplasm", "oral cancer", "oral cavity cancer", "oral squamous cell carcinoma", "tongue cancer", "margins of excision", "surgical margin" and "resection margin". We found approximately 998 articles on PubMed and 2227 articles on EMBASE. A total of 3225 articles was identified, and 2763 of those were left after removing the duplicates. By applying advanced filters about the relevance of the subjects, these were narrowed down to 111 articles. After the final exclusion, 42 full-text articles were reviewed. The universal cut-off criteria of 5 mm used for determining the resection margin status has been debated due to recent studies evaluating the impact of different margin criteria on patient prognosis. Of note, the degree of the microscopic extension from the gross tumor border correlates with tumor dimensions. Therefore, a relatively narrow safety margin can be justified in early-stage oral cancer without the additional risk of recurrence, while a wide safety margin might be required for advanced-stage oral cancer. This review suggests a surgical strategy to adjust the criteria for risk grouping and adjuvant treatments, according to individual tumor dimensions or characteristics. In the future, it might be possible to establish individual tumor-specific surgical margins and risk stratification during or after surgery. However, the results should be interpreted with caution because there is no strong evidence (e.g., prospective randomized controlled studies) yet to support the conclusions. Our study is meaningful in suggesting future research directions and discussions.

Effect of formalin fixation on tumour size and margins in head and neck cancer specimens

Objectives

To quantify tumour size and margin shrinkage due to formalin fixation in head and neck cancer specimens and determine its effect on tumour staging and margin clearance.

Methods

Tumour specimens were measured immediate post-resection and at 24 hours after fixation. Tumour was measured in 2 dimensions and one margin was measured. Shrinkage was categorised as < 10%, 10-20%, and > 20%. Effect of shrinkage on tumour stage and margin clearance were evaluated.

Results

A total of 50 specimens were analysed. The tumour AP (Anterior Posterior) and SI (Superior Inferior) measurements showed significant shrinkage with a mean difference of 22.93% and 21.69% respectively. > 20% shrinkage was noted in 78% of AP and 58% of SI measurements. Margins showed a mean difference of 25.61%. 84% of margins demonstrated > 20% shrinkage. In all, 46.7% of T3 and 23% of T2 tumours pre-fixation were downstaged to T2 and T1, respectively, post-fixation.

Conclusions

Formalin fixation alone can be responsible for significant shrinkage of tumour and margin dimensions in head and neck specimens. It is suggested that decisions regarding the treatment plan should be made on clinical staging of primary tumour rather than pathological staging. In addition, post-excision pre-fixation margins should be considered for treatment planning.

Personalized Targeted Therapeutic Strategies against Oral Squamous Cell Carcinoma. An Evidence-Based Review of Literature

Oral squamous cell carcinoma (OSCC) is the most common type of malignant tumor in the head and neck, with a poor prognosis mainly due to recurrence and metastasis. Classical treatment modalities for OSCC like surgery and radiotherapy have difficulties in dealing with metastatic tumors, and together with chemotherapy, they have major problems related to non-specific cell death. Molecular targeted therapies offer solutions to these problems through not only potentially maximizing the anticancer efficacy but also minimizing the treatment-related toxicity. Among them, the receptor-mediated targeted delivery of anticancer therapeutics remains the most promising one. As OSCC exhibits a heterogeneous nature, selecting the appropriate receptors for targeting is the prerequisite. Hence, we reviewed the OSCC-associated receptors previously used in targeted therapy, focused on their biochemical characteristics and expression patterns, and discussed the application potential in personalized targeted therapy of OSCC. We hope that a better comprehension of this subject will help to provide the fundamental information for OSCC personalized therapeutic planning.

Intraoperative In Vivo Imaging Modalities in Head and Neck Cancer Surgical Margin Delineation: A Systematic Review

Surgical margin status is one of the strongest prognosticators in predicting patient outcomes in head and neck cancer, yet head and neck surgeons continue to face challenges in the accurate detection of these margins with the current standard of care. Novel intraoperative imaging modalities have demonstrated great promise for potentially increasing the accuracy and efficiency in surgical margin delineation. In this current study, we collated and analyzed various intraoperative imaging modalities utilized in head and neck cancer to evaluate their use in discriminating malignant from healthy tissues. The authors conducted a systematic database search through PubMed/Medline, Web of Science, and EBSCOhost (CINAHL). Study screening and data extraction were performed and verified by the authors, and more studies were added through handsearching. Here, intraoperative imaging modalities are described, including optical coherence tomography, narrow band imaging, autofluorescence, and fluorescent-tagged probe techniques. Available sensitivities and specificities in delineating cancerous from healthy tissues ranged from 83.0% to 100.0% and 79.2% to 100.0%, respectively, across the different imaging modalities. Many of these initial studies are in small sample sizes, with methodological differences that preclude more extensive quantitative comparison. Thus, there is impetus for future larger studies examining and comparing the efficacy of these intraoperative imaging technologies.

Margin Sampling and Survival Outcomes in Oral Cavity and p16-Positive Oropharyngeal Squamous Cell Carcinoma

Objective

To compare the association of margin sampling technique on survival outcomes in surgically treated cT1-2 oral cavity and oropharyngeal squamous cell carcinoma.

Study Design

A prospective longitudinal cohort study.

Setting

Tertiary care academic teaching hospital in Halifax, Nova Scotia.

Methods

All cases of surgically treated cT1-2 oral cavity and oropharyngeal cancer undergoing specimen-oriented margin analysis between January 1, 2017, and December 31, 2018 were analyzed. The specimen-oriented cohort was compared with a cohort of patients from January 1, 2009, to December 31, 2014, where a defect-oriented margin sampling protocol was used. Kaplan-Meier survival curves were used to estimate 2-year overall survival, disease-specific survival, local control, and recurrence-free survival rates in oral cavity and p16-positive oropharyngeal squamous cell carcinoma. Cox proportional hazards models were used to assess the effect of margin sampling method on disease-specific survival and local control.

Results

There was no significant association between margin sampling technique and 2-year survival outcomes for surgically treated cT1-2 oral cavity and oropharyngeal squamous cell carcinoma. In the multivariate Cox proportional hazard model, the hazard ratio (HR) of specimen-oriented sampling was not significantly different for disease-specific survival (HR, 1.32; 95% CI, 0.3032-5.727; P = .713) or local control (HR, 0.4087; 95% CI, 0.0795-2.099; P = .284).

Conclusion

Intraoperative margin sampling method was not associated with a significant change in 2-year survival outcomes. Despite no effect on survival outcomes, implementation of a specimen-oriented sampling method has potential for cost avoidance by decreasing the number of re-resections for positive or close margins.

Emerging applications of nanobodies in cancer therapy

Cancer is a heterogeneous disease, requiring treatment tailored to the unique phenotype of the patient's tumor. Monoclonal antibodies (mAbs) and variants thereof have enabled targeted therapies to selectively target cancer cells. Cancer cell-specific mAbs have been used for image-guided surgery and targeted delivery of radionuclides or toxic agents, improving classical treatment strategies. Cancer cell-specific mAbs can further inhibit tumor cell growth or can stimulate immune-mediated destruction of cancer cells, a feature that has also been achieved through mAb-mediated manipulation of immune cells and pathways. Drawbacks of mAbs and their variants, together with the discovery of camelid heavy chain-only antibodies and the many advantageous features of their variable domains, referred to as V_HHs, single domain antibodies or nanobodies (Nbs), resulted in the exploration of Nbs as an alternative targeting moiety. We therefore review the state-of-the-art as well as novel exploitation strategies of Nbs for targeted cancer therapy.

Intraoperative imaging in pathology-assisted surgery

The pathological assessment of surgical specimens during surgery can reduce the incidence of positive resection margins, which otherwise can result in additional surgeries or aggressive therapeutic regimens. To improve patient outcomes, intraoperative spectroscopic, fluorescence-based, structural, optoacoustic and radiological imaging techniques are being tested on freshly excised tissue. The specific clinical setting and tumour type largely determine whether endogenous or exogenous contrast is to be detected and whether the tumour specificity of the detected biomarker, image resolution, image-acquisition times or penetration depth are to be prioritized. In this Perspective, we describe current clinical standards for intraoperative tissue analysis and discuss how intraoperative imaging is being implemented. We also discuss potential implementations of intraoperative pathology-assisted surgery for clinical decision-making.

Robotic vs. transoral laser surgery of malignant oropharyngeal tumors-what is best for the patient? : A contemporary review

Human papillomavirus (HPV)-associated squamous cell carcinoma of the oropharynx is a malignancy of increasing prevalence. The oncologic community is currently evaluating the safety and efficacy of de-intensifying treatment without compromising oncologic outcomes. Paramount to these treatment algorithms is primary surgery through transoral approaches. This article reviews the literature and concepts pertaining to transoral surgery and describes the two most common techniques, transoral laser microsurgery (TLM) and transoral robotic surgery (TORS).

Multicentre study on resection margins in carcinoma of the oral cavity, oro-hypopharynx and larynx

Objective

The prognostic significance of the resection margins is still subject of conflicting opinions. The purpose of this paper is to report the results of a study on the margins in carcinoma of the oral cavity, oro-hypopharynx and larynx.

Methods

A multicentre prospective study was carried out between 2015 and 2018 with the participation of 10 Italian reference hospitals. The primary objective was to evaluate local control in patients with well-defined clinical characteristics and comprehensive histopathological information.

Results

During the study period, 455 patients were enrolled; the minimum follow-up was 2 years. Previous treatment, grading and fresh specimen examination were identified as risk factors for local control in multivariate analysis. On the basis of these results, it seems possible to delineate “risk profiles” for different oncological outcomes.

Discussion

The prognostic significance of the margins is reduced, and other risk factors emerge, which require diversified treatment and follow-up.

Conclusions

Multidisciplinary treatment with adjuvant therapy, if indicated, reduces the prognostic importance of margins. Collaboration with a pathologist is an additional favourable prognostic factor and quality indicator.

An appendix with literature review is present in the online version.