Clinical relevance of the utilization of vital Lugol's iodine staining in detection and diagnosis of oral cancer and dysplasia

Application of narrow band imaging and Lugol's iodine staining in screening for nasopharyngeal carcinoma

BACKGROUND

To investigate the diagnostic value of conventional white light endoscopy (WLE), narrow band imaging (NBI) endoscopy, and Lugol's iodine staining under WLE (endoscopic iodine staining) in the screening and early diagnosis of nasopharyngeal carcinoma.

METHODS

Patients with nasopharyngeal lesions requiring biopsy attending the Department of Otolaryngology Head and Neck Surgery in our hospital between January 2021 and April 2023 were included in this study. Before biopsy, all subjects underwent conventional WLE, NBI endoscopy, and endoscopic iodine staining. On WLE, according to nasopharyngeal lesion morphology and color, patients were diagnosed with nasopharyngeal carcinoma ( +) or chronic hyperplastic nasopharyngitis (-). On NBI endoscopy, according to nasopharyngeal lesion vascular morphology, patients with type V manifestations (nasopharyngeal carcinoma) were categorized as NBI ( +) and patients with type I-IV manifestations (chronic hyperplastic nasopharyngitis) were categorized as NBI (-). Endoscopic iodine staining (1.6% Lugol's iodine solution) was positive ( +) if the mucosal surface was brown with no white patches, or negative (-) if there was no or light brown staining of the mucosal surface. Patients were divided into 2 groups based on histopathological diagnosis: nasopharyngeal carcinoma or chronic hyperplastic nasopharyngitis. Endoscopic diagnoses were compared with histopathological findings. The diagnostic performance of WLE, NBI endoscopy and endoscopic iodine staining for nasopharyngeal carcinoma were determined.

RESULTS

This study included 159 patients. On histopathology, 29 patients were diagnosed with nasopharyngeal carcinoma, and 130 patients were diagnosed with chronic hyperplastic nasopharyngitis. There were no significant differences in the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and area under the receiver operating characteristic (ROC) curve (AUC) of conventional WLE, NBI endoscopy or endoscopic iodine staining for differentiating nasopharyngeal carcinoma and chronic hyperplastic nasopharyngitis. The diagnostic performance of the combination of conventional WLE, NBI endoscopy and endoscopic iodine staining was significantly improved compared to any procedure alone.

CONCLUSIONS

Conventional WLE, NBI endoscopy or endoscopic iodine staining had good diagnostic performance for differentiating nasopharyngeal carcinoma and chronic hyperplastic nasopharyngitis. In particular, NBI endoscopy and endoscopic iodine staining alone or combined had clinical utility for identifying patients with nasopharyngeal lesions that are eligible for a watch-and-wait strategy.

Combination of fluorescence visualization and iodine solution-guided surgery for local control of early tongue cancer

The control of enclosed oral epithelial dysplasia is important for the control of oral cancer. Fluorescence visualization and iodine solution are able to detect oral epithelial dysplasia and surrounding oral cancer. The purpose of this study was to clarify the effectiveness of combining fluorescence visualization and iodine solution-guided surgery for early tongue cancer. Participants comprised 264 patients with primary early tongue cancer who underwent surgery. The surgical margin was set at 10 mm outside the clinical tumour, and 5 mm outside the area of fluorescence visualization loss, and 5mm outside the iodine unstained area. The 5-year disease-free survival rate was 87.1% vs 76.1% (P = 0.016) and the 5-year local control rate was 98.6% vs 93.0% (P = 0.008) for combination-guided surgery when compared to conventional surgery. Positive margin rates were 0% for cancer, and 6.5% and 0% for low- and high-grade dysplasia, respectively, with combination-guided surgery (P = 0.257). Multivariate analysis revealed that combination-guided surgery (odds ratio 0.140, 95% confidence interval 0.045-0.437; P < 0.001) and intraoperative frozen section examination (odds ratio 0.302; 95% confidence interval 0.115-0.791; P = 0.015) were significantly associated with local control. The combination of fluorescence visualization and iodine solution are effective in selecting surgical margins for early tongue cancer.

A Systematic Review of Oral Biopsies, Sample Types, and Detection Techniques Applied in Relation to Oral Cancer Detection

Background: Early identification of the stage of oral cancer development can lead to better treatment outcomes and avoid malignant transformation. Therefore, this review aims to provide a comprehensive overview that describes the development of standardized procedures for oral sample collection, characterization, and molecular risk assessment. This can help investigators to choose the appropriate sampling method and downstream analyses for different purposes. Methods: This systematic review was conducted according to the PRISMA guidelines. Using both PubMed and Web of Science databases, four independent authors conducted a literature search between 15 and 21 June 2021. We used key search terms to broaden the search for studies. Non-conforming articles were removed using an EndNote-based and manual approach. Reviewers used a designed form to extract data. Results: This review included a total of 3574 records, after eliminating duplicate articles and excluding papers that did not meet the inclusion criteria. Finally, 202 articles were included in this review. We summarized the sampling methods, biopsy samples, and downstream analysis. The biopsy techniques were classified into tissue and liquid biopsy. The common sequential analysis of tissue biopsy includes histopathological examination such as H&E or IHC to identify various pathogenic features. Meanwhile, liquid samples such as saliva, blood, and urine are analyzed for the purpose of screening to detect mutations in cancer. Commonly used technologies are PCR, RT-PCR, high-throughput sequencing, and metabolomic analysis. Conclusions: Currently, tissue biopsies provide increased diagnostic value compared to liquid biopsy. However, the minimal invasiveness and convenience of liquid biopsy make it a suitable method for mass screening and eventual clinical adoption. The analysis of samples includes histological and molecular analysis. Metabolite analysis is rising but remains scarce.

Clinical value of entire-circumferential intraoperative frozen section analysis for the complete resection of superficial squamous cell carcinoma of the tongue

OBJECTIVES

We aimed to evaluate the clinical value of an entire-circumferential intraoperative frozen section analysis (e-IFSA) for the complete resection of superficial squamous cell carcinoma (SCC) of the tongue.

MATERIALS AND METHODS

A total 276 specimens from 51 patients with pT1-2, N0, mucosal or submucosal invasion SCC were analyzed to evaluate the diagnostic accuracy of the e-IFSA and the added value of the e-IFSA to iodine staining. The e-IFSA results were compared with the final histologic results obtained using permanent sections. All specimens for the e-IFSA were taken over the entire circumference 5 mm outside from the iodine unstained areas. The outline of the main resected specimen after taking these outer mucosal specimens were defined as the surgical margins determined by iodine staining alone.

RESULTS

The e-IFSA results were in excellent agreement with final histological results (Cohen's kappa value: 0.85) and the e-IFSA showed high sensitivity (100%) and high negative predictive value (100%). The actual complete resection rate with an e-IFSA was 100% (51/51), and no patient required additional resection after surgery. In contrast, 10/51 patients (20%) patients showed residual atypical mucosal epithelium at or beyond the margin determined by iodine staining alone; this difference was statistically significant (P = 0.002). The 5-year local control rate and 5-year overall survival rate after this procedure were both 100%.

CONCLUSION

An e-IFSA has additional value when performed in conjunction with iodine staining. An e-IFSA would be useful for achieving complete resection of superficial SCC of the tongue.

Non-Invasive Early Detection of Oral Cancers Using Fluorescence Visualization with Optical Instruments

Simple Summary

Oral cancer has a high mortality rate. Then, oral cancer screening is needed for early detection and treatment. Fluorescence visualization is non-invasive, convenient, and in real-time, and examinations can be repeated. Our study aimed to show the usefulness of oral cancer screening with fluorescence visualization. A total of 502 patients were performed using fluorescence visualization that was analyzed using subjective and objective evaluation. Results of this study, subjective evaluation for detection oral cancer was high sensitivity and low specificity, while objective evaluation using imaging processing analysis was high sensitivity and high specificity. Therefore, oral cancer screening using fluorescence visualization is useful for the detection of oral cancer. The widespread use of this screening can reduce the mortality rate of oral cancer.

Abstract

Background: Oral cancer screening is important for early detection and early treatment, which help improve survival rates. Biopsy is the gold standard for a definitive diagnosis but is invasive and painful, while fluorescence visualization is non-invasive, convenient, and real-time, and examinations can be repeated using optical instruments. The purpose of this study was to clarify the usefulness of fluorescence visualization in oral cancer screening. Methods: A total of 502 patients, who were examined using fluorescence visualization with optical instruments in our hospitals between 2014 and 2019, were enrolled in this study. The final diagnosis was performed by pathological examination. Fluorescence visualization was analyzed using subjective and objective evaluations. Results: Subjective evaluations for detecting oral cancer offered 96.8% sensitivity and 48.4% specificity. Regarding the objective evaluations, sensitivity and specificity were 43.7% and 84.6% for mean green value, 55.2% and 67.0% for median green value, 82.0% and 44.2% for coefficient of variation of value, 59.6% and 45.3% for skewness, and 85.1% and 75.8% for value ratio. For the sub-analysis of oral cancer, all factors on objective and subjective evaluation showed no significant difference. Conclusions: Fluorescence visualization with subjective and objective evaluation is useful for oral cancer screening.

Use of RGB values in the Periodic Acid-Schiff color test to determine the presence of vaginal fluid

This study demonstrates how RGB color values from microscopic smears stained with the Periodic Acid-Schiff reagent under standardized microscopy conditions can be used to indicate the presence of vaginal secretions. Based on data obtained in the study, a numeric threshold determined from the sum of separate values for red, blue and green was determined to differentiate vaginal-based samples with other body fluids. Using this threshold, 55 of 57 vaginal-based samples tested positive for the presence of vaginal secretion. Conversely, 27 of 29 smears prepared from other body fluids yielded negative results. However, when graphing RGB sum values against a calculated RGB integer no overlap in data was obtained between all vaginal-based samples and other body fluid samples, clearly differentiating them. One-way ANOVA testing with a 95% confidence interval indicated that vaginal samples from different age groups showed no difference in RGB sum values. Similarly, the location that vaginal swabs were collected (from the outside of a condom or a vaginal swab) also showed no statistical difference using one-way ANOVA at 95% confidence. Furthermore, refrigerated test swabs aged up to 15 months showed no demonstrable differences. Pair-wise t-testing using RGB sum values, however, did show significant differences between vaginal samples and all other body fluids tested. Finally, the method successfully differentiated between pre-and post-coital penile swabs and finger swabs taken before and after digital vaginal penetration in anecdotal comparisons using the method.