27 November 2012
Sensitivity and specificity for detecting basal cell carcinomas in Mohs excisions with confocal fluorescence mosaicing microscopy
Gareau D., Karen J., Dusza S., Tudisco M., Nehal K., Rajadhyaksha M.
Recent studies have demonstrated the ability of confocal
fluorescence mosaicing microscopy to rapidly detect basal cell carcinomas
BCCs directly in thick and fresh Mohs surgical excisions.
Mosaics of confocal images display large areas of tissue with high
resolution and magnification equivalent to 2, which is the standard
magnification when examining pathology. Comparison of mosaics to
Mohs frozen histopathology was shown to be excellent for all types of
BCCs. However, comparisons in the previous studies were visual and
qualitative. In this work, we report the results of a semiquantitative
preclinical study in which 45 confocal mosaics are blindly evaluated
for the presence or absence of BCC tumor. The evaluations are made
by two clinicians: a senior Mohs surgeon with prior expertise in interpreting
confocal images, and a novice Mohs fellow with limited experience.
The blinded evaluation is compared to the gold standard of
frozen histopathology. BCCs are detected with an overall sensitivity of
96.6%, specificity of 89.2%, positive predictive value of 93.0%, and
negative predictive value of 94.7%. The results demonstrate the potential
clinical utility of confocal mosaicing microscopy toward rapid
surgical pathology at the bedside to expedite and guide surgery.