Lugol's iodine identifies dysplastic tissue in precancerous lesions: A clinical trial

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.

Oral leukoplakia: A review of clinical features and trends in management

Introduction: Oral potentially malignant disorders (OPMD) conisit of the group of diseases of great importance for dentists. Oral leukoplakia (OL) has long been the subject of debate by numerous researchers. A common etiologic factor is tobacco, which is associated with oral cancer. The aim of the study is to indicate the severity of the lesion, the most common clinical characreistics and localization. The prevalence of leukoplakia in the world is 2.6% with a rate of malignant conversion ranging from 0.1% to 17.5%. Literature data about the prevalence and annual rate of malignant transformation, approximately 2%, indicate that these changes should be taken seriously and regularymonitored Conclusion: Occurate diagnosis provides the key to preventing to malignant transformation. Various medical and surgical treatment modalities for this lesion have been described. This article highlights various trends in the diagnosis and treatment of oral leukoplakia.

Oral potentially malignant disorders: clinical diagnosis and current screening aids: a narrative review

Around 300 000 patients are estimated to have oral cancer worldwide annually, and the incidence is higher in South Asian countries. In 2005, at the Congress of WHO, the term potentially malignant disorder (PMD)/lesion was suggested as a replacement for premalignant oral lesions and conditions. PMDs are those lesions of the oral mucosa that are at an increased risk of malignant transformation compared with the healthy mucosa. PMDs consist of leukoplakia, erythroplakia, oral lichen planus, oral submucous fibrosis, and other miscellaneous lesions. A literature search was performed using PubMed, Scopus, and Web of Science without any language restrictions. There is no standardized method for identifying a site for biopsy and various methods such as toluidine blue stain, methylene blue, Lugol's iodine, and chemiluminescence have been proposed in the literature. Despite easy access to the oral cavity, there has been significant mortality associated with oral cancer as they are often diagnosed late because of the inability of healthcare professionals to identify them at early premalignant states. This article aims to provide healthcare professionals with the knowledge to identify potentially malignant disorders and to aid them in biopsy site identification.

Fluorescence-guided resection of tumors in mouse models of oral cancer

Complete removal and negative margins are the goal of any surgical resection of primary oral cavity carcinoma. Current approaches to determine tumor boundaries rely heavily on surgeons' expertise, and final histopathological reports are usually only available days after surgery, precluding contemporaneous re-assessment of positive margins. Intraoperative optical imaging could address this unmet clinical need. Using mouse models of oral cavity carcinoma, we demonstrated that PARPi-FL, a fluorescent PARP inhibitor targeting the enzyme PARP1/2, can delineate oral cancer and accurately identify positive margins, both macroscopically and at cellular resolution. PARPi-FL also allowed identification of compromised margins based on fluorescence hotspots, which were not seen in margin-negative resections and control tongues. PARPi-FL was further able to differentiate tumor from low-grade dysplasia. Intravenous injection of PARPi-FL has significant potential for clinical translation and could aid surgeons in assessing oral cancer margins in vivo.

Surgical margins in oral cavity squamous cell carcinoma: Current practices and future directions

OBJECTIVE

To discuss the current available techniques for intraoperative margin assessment in the surgical treatment of oral squamous cell carcinoma (OSCC) through a review of the available literature.

METHODS

A systematic review was undertaken of the available English literature between 2008 through 2018 regarding surgical margins in OCSS. A total of 893 relevant articles were returned; 144 met criteria for review; and 64 articles were included.

RESULTS

In this review, we discuss the data surrounding the use of frozen section in OCSS. Additionally, alternative techniques for margin assessment are discussed, including Mohs, molecular analysis, nonfluorescent dyes, fluorescent dyes, autofluorescent imaging, narrow-band imaging, optical coherence tomography, confocal microscopy, high-resolution microendoscopy, and spectroscopy. For each technique, particular emphasis is placed on the local recurrence, disease-free survival, and overall survival rates when available.

CONCLUSION

This review provides support for the practice of specimen-driven margin assessment when using frozen section analysis to improve the utility of the results. Finally, several alternatives for intraoperative margin assessment currently under investigation, including pathologic, wide-field imaging and narrow-field imaging techniques, are presented. We aim to fuel further investigation into methods for margin assessment that will improve survival for patients with OSCC through a critical analysis of the available techniques.

LEVEL OF EVIDENCE

NA Laryngoscope, 130:128-138, 2020.