Refined clinico-pathologic correlation of melanocytic lesions using dermoscopy has lead to support pathologists to come to more reliable diagnostic conclusions. Despite the promising premise, this integration between dermoscopy and histology was discovered to be effective only in a limited number of scientific works. More recently, according to the necessity of a more detailed correlation, in-vivo reflectance confocal microscopy demonstrated to increase sensitivity of dermoscopy alone, but the really problematic melanocytic lesions still remain an unsolved issue.
In the era of molecular biology, ex-vivo dermoscopy guided sampling of melanocytic lesions has opened a new prospective of integration between non-invasive method of diagnosis, histology and molecular biology with the creation of a biobank. Following, sub-millimetre skin punch biopsy devices, named microbiopsies, for minimally invasive and suture-free skin sampling for molecular diagnosis have been proposed for in-vivo dermoscopy guided biobanking.
Based on a preliminary experience with dermoscopy guided microbiopsies in-vivo sampling, we recently developed a targeted microbiopsy device for RCM pre-selected targets based on the virtual grid provided by RCM mosaics. In order to test the efficacy of the new device, melanocytic lesions (reticular and globular nevi) from volunteers have been considered and RCM selected microscopic structures have been targeted.
Our preliminary test showed good approximation in targeting the RCM pre-selected areas with an error that was estimated to be less than 0.5 mm. RCM performed after the sampling procedure demonstrated good integrity of tissue with no major damage of the skin surrounding the site of microbiopsies. The micro-samples obtained underwent to RNA extraction; later, obtained RNA was examined with real time qRT-PCR for tyrosinase that was positive in all the samples examined.
Our new device for RCM targeted microbiopsy allows a direct and more precise correlation between in vivo detectable microscopic features and molecular biology. Moreover, it seems to be more feasible to avoid area of hyperkeratosis, acanthosis, regression area or area with limited number of melanocytes in order to provide more adequate sampling for molecular biology and limit sampling errors. Moreover, the device for RCM guided sampling seems to better “stabilize” the microbiopsy, providing a more successful sampling.
In conclusion, our RCM guided microbiopsy device combines a non-invasive, real time “quasi histology” microscopic technique for melanocytic lesions with the rapid molecular biobanking.