Accuracy of Ex-vivo Fluorescence Confocal Microscopy in Margin Assessment of Solid Tumors: A Systematic Review

Abstract

Fluorescence confocal microscopy (FCM) is a novel technology that enables rapid high-resolution digital imaging of non-formalin-fixed tissue specimens and offers real-time positive surgical margin identification. In this systematic review, we evaluated the accuracy metrics of ex vivo FCM for intraoperative margin assessment of different tumor types. A systematic search of MEDLINE via PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus was performed for relevant papers (PROSPERO ID: CRD42022372558). We included 14 studies evaluating four types of microscopes in six different tumor types, including breast, prostate, central nervous system, kidney, bladder, and conjunctival tumors. Using the Quality Assessment of Diagnostic Accuracy Studies tool, we identified a high risk of bias in patient selection (21%) and index test (36%) of the included studies. Overall, we found that FCM has good accuracy metrics in all tumor types, with high sensitivity and specificity (>80%) and almost perfect concordance (>90%) against final pathology results. Despite these promising findings, the quality of the available evidence and bias concerns highlight the need for adequately designed studies to further define the role of ex vivo FCM in replacing the frozen section as the tool of choice for intraoperative margin assessment:

Ex Vivo Fluorescence Confocal Microscopy for Intraoperative Examinations of Lung Tumors as Alternative to Frozen Sections—A Proof-of-Concept Study

“…The technique is established in routine dermatopathology [ 11 , 12 ] in Moh’s surgery of skin tumors for intraoperative control of surgical margins [ 13 ] and in the context of inflammatory dermatoses [ 14 , 15 ]. Its suitability for extracutaneous surgical pathology was recognized comparatively late [ 16 ], and only in recent years have the instruments been established in a growing number of centers [ 17 ]. Most experience has been gained in the field of urological practice [ 18 ], particularly in the biopsy diagnosis of prostate carcinomas [ 19 , 20 , 21 ] and as an alternative to frozen sections in prostatectomies [ 22 , 23 , 24 ].…”