The BASIC Classification: does it shed (blue) light on colorectal polyp differentiation?

“Vision is the art of seeing what is invisible to others.”
Jonathan Swift

In recent years, the vision of using optical diagnosis to guide colorectal polyp management at the moment of detection has challenged the standard of universal resection and pathology for all polyps [1]. In the optical diagnosis paradigm, ubiquitous diminutive rectosigmoid polyps without malignant potential could be left in situ, diminutive adenomas could be resected without formal pathology and their presence considered in surveillance interval calculations, and deeply submucosal invasive cancers could be biopsied and marked for surgical resection [2]. Image-enhancement tools and optical magnification have illuminated features of polyps previously “invisible” with white light alone, and provided tools to advance optical diagnosis closer toward reality.

“BASIC falls short of providing a user-friendly tool for optical diagnosis, but its shortcomings provide insights to improve future work.”

Blue-light imaging (BLI) is one of these tools. BLI, which has been recently integrated into Fujinon colonoscopes available in Europe, directly shines a blue light, which is optimally absorbed by hemoglobin. By contrast, narrow-band imaging used in Europe and the United States (Olympus Exera) employs an optical filter during image processing, and the Pentax I-SCAN system enhances each of three primary color components of an image before calculating the virtual image [3].

In this issue of Endoscopy, Bisschops et al. describe their use of BLI to develop a new optical diagnosis classification system, called BASIC (BLI Adenoma Serrated International Classification) [4].

• References

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