Probe-Based Confocal Laser Endomicroscopy Effective in Detecting Head and Neck Cancers

by Amy Hamaker •

How feasible is the use of probe-based confocal laser endomicroscopy (pCLE) in standard practice for detecting head and neck cancers?

Background: pCLE is an emerging optical imaging technology that is rapidly being adopted for its ability to provide real-time, in-situ, histological visualization of tissue in the operating room. In 2013, oral cavity, pharyngeal, and laryngeal cancers accounted for a combined 53,640 new cancer cases in the United States alone. Despite modern advances in diagnosis and treatment, prognosis remains poor.

Study design: Six nondysplasia, seven dysplasia, and 11 squamous cell carcinoma (SCCA) cases reviewed at a single tertiary referral center.

Setting: Feist-Weiller Cancer Center, Louisiana State University Health Shreveport, Shreveport.

Synopsis: The study’s senior author formulated image classification criteria and descriptions alongside example pCLE images and short videos, which were incorporated into a brief slideshow. Seven surgeons and one pathologist at various levels of training and technology exposure completed the self-guided training slideshow. These practitioners were then given another slideshow of 50 pCLE images and 10 pCLE videos to review and categorize into normal or nondysplasia, dysplasia, or cancer.

Overall agreement among physicians and pathology reports was substantial. Highest accuracy was achieved in comparing the diagnosis of carcinoma versus nondysplastic tissue, with sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) each being 100%. Accuracy in the comparison of dysplasia and nondysplasia resulted in sensitivity 80%, specificity 100%, PPV 100%, and NPV 80%. Accuracy in comparing carcinoma and dysplasia resulted in sensitivity 85.7%, specificity 100%, PPV 100%, and NPV 80%.

Limitations included a small sample size of observers who were not stratified based on prior experience, the use of all high-quality images, and post hoc rather than real-time image and video assessment.

Bottom line: pCLE allows for differentiation of normal mucosa, dysplasia, and invasive SCCA with high accuracy and reliability after short, self-guided training.

Citation: Moore C, Mehta V, Ma X, et al. Interobserver agreement of confocal laser endomicroscopy for detection of head and neck neoplasia. Laryngoscope. 2016;126:632-637.