Scattering-Based Light-Sheet Microscopy Imaging of Human Papillomavirus-Associated Squamous Lesions of the Anal Canal: A Proof-of-Principle Study.

Demand for anal cancer screening is expected to rise following the recent publication of the Anal Cancer-HSIL Outcomes Research trial, which showed that treatment of high-grade squamous intraepithelial lesions significantly reduces the rate of progression to anal cancer. While screening for human papillomavirus-associated squamous lesions in the cervix is well established and effective, this is less true for other sites in the lower anogenital tract. Current anal cancer screening and prevention rely on high-resolution anoscopy with biopsies. This procedure has a steep learning curve for providers and may cause patient discomfort. Scattering-based light-sheet microscopy (sLSM) is a novel imaging modality with the potential to mitigate these challenges through real-time, microscopic visualization of disease-susceptible tissue. Here, we report a proof-of-principle study that establishes feasibility of dysplasia detection using an sLSM device. We imaged 110 anal biopsy specimens collected prospectively at our institution's dysplasia clinic (including 30 nondysplastic, 40 low-grade squamous intraepithelial lesion, and 40 high-grade squamous intraepithelial lesion specimens) and found that these optical images are highly interpretable and accurately recapitulate histopathologic features traditionally used for the diagnosis of human papillomavirus-associated squamous dysplasia. A reader study to assess diagnostic accuracy suggests that sLSM images are noninferior to hematoxylin and eosin images for the detection of anal dysplasia (sLSM accuracy = 0.87; hematoxylin and eosin accuracy = 0.80; P = .066). Given these results, we believe that sLSM technology holds great potential to enhance the efficacy of anal cancer screening by allowing accurate sampling of diagnostic tissue at the time of anoscopy. While the current imaging study was performed on ex vivo biopsy specimens, we are currently developing a handheld device for in vivo imaging that will provide immediate microscopic guidance to high-resolution anoscopy providers.

Using Initial Biopsies and Vertical Sections to Improve Trainees' Confidence in Performing Mohs Surgery.

BACKGROUND: Tissue preservation and tumor clearance are hallmarks of Mohs micrographic surgery, but no standardized method currently exists to guide trainees on how to balance the two. OBJECTIVE: The authors provided residents and fellows with additional histologic information to enhance their surgical decision-making without changing the standard methodology of Mohs surgery. METHODS AND MATERIALS: Trainees were provided initial biopsy slides (IS) and frozen vertical sections (VS) of the first Mohs layer. All Mohs layers were excised in standard fashion, and vertically oriented sections were taken from the layer without disturbing the surgical margins to obtain VS. Surveys were used to assess trainees' confidence in performing Mohs surgery with and without these tools. RESULTS: Trainees reported increased confidence in performing Mohs surgery when they reviewed IS before surgery and viewed VS of the first layer. CONCLUSION: Reviewing IS and VS improved trainees' confidence in performing Mohs surgery. This additional histological information was obtained while maintaining the usual steps of Mohs surgery. Objective information obtained from IS and VS may explain why trainees' confidence increased using this technique. Both IS and VS can be valuable teaching tools that may enhance trainees' ability to perform Mohs surgery.