Ultrastructural alterations in field carcinogenesis measured by enhanced backscattering spectroscopy

Area of Science:

• Biomedical Optics
• Cancer Research
• Spectroscopy

Background:

• Optical characterization of biological tissue aids in understanding early cancer development and clinical diagnosis.
• Low-coherence enhanced backscattering spectroscopy (LEBS) has previously distinguished normal from diseased tissue in colorectal (CRC) and pancreatic (PC) cancers.
• Enhanced backscattering (EBS) spectroscopy offers a more comprehensive approach to investigate these optical changes.

Purpose of the Study:

• To implement enhanced backscattering (EBS) spectroscopy for a detailed understanding of structural and optical changes in field carcinogenesis.
• To quantify nanoscale mass density fluctuations in the mucosa using EBS.
• To determine the specific length-scales at which spatial reflectance profiles (P(rs)) are altered in CRC and PC field carcinogenesis.

Main Methods:

• Utilized enhanced backscattering (EBS) spectroscopy to measure the spatial reflectance profile (P(rs)) over length-scales from 30 microns to 2.7 mm.
• Quantified nanoscale mass density fluctuations in mucosal tissue.
• Correlated observed optical changes with the tissue's structural composition.

Main Results:

• Significant alterations in P(rs) were observed primarily at short length-scales, corresponding to the superficial mucosal layer.
• These changes were mainly attributed to a reduction in subdiffractional structures within the tissue.
• Similar optical and structural trends were identified in both colorectal and pancreatic cancer field carcinogenesis.

Conclusions:

• The superficial mucosal layer exhibits the most significant optical changes in field carcinogenesis.
• A decrease in subdiffractional structures is a key factor driving these observed optical alterations.
• Both colorectal and pancreatic cancers show common patterns of structural changes during early development.