Early detection of skin cancer via terahertz spectral profiling and 3D imaging

• This paper introduces a new method for early detection of skin cancer and other skin maladies via terahertz technology.
• In particular biopsy skin samples with basal cell carcinoma have been analyzed and compared with healthy skin samples.
• Three different techniques are used: (i) terahertz scanning reflectometry, (ii) terahertz time-domain spectroscopy and (iii) terahertz 3D imaging.
• It is demonstrated that each method is able to distinguish between the healthy and cancerous skin samples in their own right.
• Thus the techniques collectively form a promising method for skin cancer detection on a cellular level.

Terahertz scanning reflectometry, terahertz 3D imaging and terahertz time-domain spectroscopy have been used to identify features in human skin biopsy samples diagnosed for basal cell carcinoma (BCC) and compared with healthy skin samples. It was found from the 3D images that the healthy skin samples exhibit regular cellular pattern while the BCC skin samples indicate lack of regular cell pattern. The skin is a highly layered structure organ; this is evident from the thickness profile via a scan through the thickness of the healthy skin samples, where, the reflected intensity of the terahertz beam exhibits fluctuations originating from different skin layers. Compared to the healthy skin samples, the BCC samples’ profiles exhibit significantly diminished layer definition; thus indicating a lack of cellular order. In addition, terahertz time-domain spectroscopy reveals significant and quantifiable differences between the healthy and BCC skin samples. Thus, a combination of three different terahertz techniques constitutes a conclusive route for detecting the BCC condition on a cellular level compared to the healthy skin.