Tri-modal confocal mosaics detect residual invasive squamous cell carcinoma in Mohs surgical excisions.
For rapid, intra-operative pathological margin assessment to guide staged cancer excisions, multimodal confocal mosaic scan image wide surgical margins (approximately 1 cm) with sub-cellular resolution and mimic the appearance of conventional hematoxylin and eosin histopathology (H&E). The goal of this work is to combine three confocal imaging modes: acridine orange fluorescence (AO) for labeling nuclei, eosin fluorescence (Eo) for labeling cytoplasm, and endogenous reflectance (R) for marking collagen and keratin. Absorption contrast is achieved by alternating the excitation wavelength: 488 nm (AO fluorescence) and 532 nm (Eo fluorescence). Superposition and false-coloring of these modes mimics H&E, enabling detection of cutaneous squamous cell carcinomas (SCC). The sum of mosaic Eo+R is false-colored pink to mimic the appearance of eosin, while the AO mosaic is false-colored purple to mimic the appearance of hematoxylin in H&E. In this study, mosaics of 10 Mohs surgical excisions containing invasive SCC, and five containing only normal tissue were subdivided for digital presentation equivalent to 4 × histology. Of the total 50 SCC and 25 normal sub-mosaics presented, two reviewers made two and three type-2 errors (false positives), respectively. Limitations to precisely mimic H&E included occasional elastin staining by AO. These results suggest that confocal mosaics may effectively guide staged SCC excisions in skin and other tissues.
Oregon Health & Science University, Department of Dermatology, CH16D, 3303 SW Bond Avenue, Portland, Oregon 97239, USA. dan@dangareau.net
Dan
D
Gareau
Anna
A
Bar
Nicholas
N
Snaveley
Ken
K
Lee
Nathaniel
N
Chen
Neil
N
Swanson
Eric
E
Simpson
Steve
S
Jacques
D000042:Absorption; D000165:Acridine Orange / Q000494:pharmacology; D016477:Artifacts; D002280:Basal Cell Carcinoma / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D003094:Collagen / Q000737:chemistry; D003593:Cytoplasm / Q000378:metabolism; D004801:Eosine Yellowish-(YS) / Q000737:chemistry; D005189:False Positive Reactions; D006801:Humans; D007633:Keratins / Q000737:chemistry; D018613:Microscopy, Confocal / Q000379:methods*; D015580:Mohs Surgery / Q000379:methods*; D009361:Neoplasm Invasiveness; D015203:Reproducibility of Results; D012867:Skin / Q000473:pathology; D012878:Skin Neoplasms / Q000473:pathology*
D007633:Keratins; D003094:Collagen; D000165:Acridine Orange; D004801:Eosine Yellowish-(YS)