Routine application of ex vivo confocal laser scanning microscopy with digital staining for examination of surgical margins in basal cell carcinomas

Abstract

Summary Background and objectives Ex vivo confocal laser scanning microscopy (CLSM) allows histologic examination of native tissue based on tissue reflection and nuclear fluorescence staining. The newly introduced digital staining process almost perfectly mimics conventional hematoxylin and eosin (HE) slides. The aim was to evaluate the new method in clinical routine, with regard to quality of findings and time requirements, in the examination of surgical margins of basal cell carcinomas. Patients and methods 78 patients with 101 basal cell carcinomas were prospectively enrolled. Surgery was performed either with complete margin control (n = 60) or as elliptical excision (n = 41). Immediately after excision specimens were scanned with CLSM and then routinely processed by conventional histopathology. Blinded evaluation of images and slides was performed by a dermatopathologist. Results Basal cell carcinomas were excellently recognizable by CLSM directly after excision, and the use of digital staining did not require any adjustment of the examiner’s visualization preferences. CLSM images showed a sensitivity of 73.6 % and a specificity of 96.5 % compared to conventional HE stained slides. Erroneous findings were often due to limited assessment potential in cases where the epidermis could not be fully visualized. Conclusions CLSM with digital HE staining is very well suited to diagnose basal cell carcinomas and their incision margins even under routine conditions and thus represents a tissue‐saving alternative to rapid cryostat sectioning.

Diagnostic Accuracy of Digital Staining ex vivo Confocal Microscopy for Diagnosing and Subtyping Basal Cell Carcinoma in Fresh Pretherapeutic Punch Biopsies: A Monocentric Prospective Study

“…These studies have reported an overall sensitivity and specificity for detecting BCC of 73–96.6% and 89.2–99%, respectively, when compared to HE-stained paraffin or frozen sections. More recently, Grupp et al [8] used the same EVCM as us and achieved a sensitivity of 73.6% and a specificity of 96.5%, in surgical margins of 101 cases of BCC, when compared to HE paraffin sections. Most of these works involved ex vivo CM experts, with prior experience in CM interpretation [8, 22].…”

“…More recently, Grupp et al [8] used the same EVCM as us and achieved a sensitivity of 73.6% and a specificity of 96.5%, in surgical margins of 101 cases of BCC, when compared to HE paraffin sections. Most of these works involved ex vivo CM experts, with prior experience in CM interpretation [8, 22]. In our study, the great similarity between the EVCM images and those obtained from HE-stained paraffin sections rendered their interpretation accessible to a pathologist novice in CM.…”

“…A new ex vivo confocal microscopy using fusion mode and digital staining (EVCM) has recently been developed, using two lasers with different wavelengths (488 nm and 785 nm) and combining reflectance and fluorescence in the same image to generate with an integrated algorithm 2-color images mimicking conventional hematoxylin-eosin (HE) staining [5]. This EVCM allows for faster pathology assessment with greater accuracy by the visualization of cellular and architectural details, similarly to standard pathology [6][7][8]. Indeed, this new device could represent an alternative to histological examination of the pretherapeutic BCC punch biopsy, the current gold standard.…”

Machine Learning Based Prediction of Squamous Cell Carcinoma in Ex Vivo Confocal Laser Scanning Microscopy

“…Analogous issues were observed in other studies conducted on digitally scanned conventional H&E stained BCC slides [ 63 ]. Similar false positive results also do occur during assessment of CLSM images by experienced dermatohistopathologists, as these structures are difficult to differentiate [ 72 ]. Therefore, this limitation is not confined to the algorithm itself and partly stem from the reduced contrast and image quality.…”

A Feasibility Study for Immediate Histological Assessment of Various Skin Biopsies Using Ex Vivo Confocal Laser Scanning Microscopy

“…Most of the data are available for the diagnosis of basal cell carcinomas (BCC). In this case, a high specificity and sensitivity could be demonstrated in comparison to H&E diagnostics [ 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ]. An important application is particularly in the use of Mohs surgery.…”