POTENTIAL OF TERAHERTZ PULSED REFLECTOMETRY AND IMAGING FOR THE EARLY DIAGNOSIS OF CUTANEOUS MELANOMA

In the last two decades the incidence rate of cutaneous malignant melanoma have been risen faster than any other form of cancer worldwide in the white-Caucasian population. The mortality rates over time show that an early diagnosis is the key point for quick treatment, which increase survival rates.

As a standard procedure dermatologists use a dermascope or the naked eye for evaluation of possible lesions, where experts have a higher chance of spotting infiltrated tissue than untrained persons.

Multiple investigations on diagnostic imaging for the detection of melanoma have been conducted in the past, like Ultrasound, Near-Infrared spectroscopy or Optical Coherence Tomography, with mixed, but not sufficient results to date.

In recent years terahertz radiation has shown to be a promising technology for the early detection of various types of cancers, i.e., colon ex-vivo}, breast ex-vivo and non-melanoma skin cancers ex-vivo andmin-vivo as terahertz radiation is able to penetrate slightly into the bio-tissue but also deemed to be a non-ionising and therefore safe method for diagnosis of lesions in-vivo.

Investigations into the practicality and benefits of using terahertz reflectometry for the early diagnosis of melanoma has never been performed.

Therefore, as a pilot study, an investigation into the modalities of utilising terahertz technology on freshly excised human cutaneous melanoma is anticipated, which includes a comparison of the collected 3D terahertz images with visuals, comparison of histopathologists findings but also investigations about modelling skin and abnormalities of the skin using terahertz radiation.

Diverse and manifold results can be reported based on the study conducted, which show that there is a good potential of terahertz detecting abnormalities on a per patient basis of up to 78% sensitivity and 95% specificity respectively. However, skin is a very diverse medium and results of the modelling approach have to be seen very critically. As modality for a diagnostic tool, this investigation suggests that there is potential in detecting margins and active regions of cancerous region spreading, which may help to support the dermatologists to determine better margins for the excision of the lesion.