Knowing in advance if a melanoma will tend to spread to other organs could become easier thanks to what dermatologists see with a special lens on the skin: the dermatoscope. This is what emerges from an international study just published by Nature Communications, one of the most prestigious scientific journals in the world, in which Prof. Iris Zalaudek (Department of Medical, Surgical and Health Sciences) participated with a research team from the University of Trieste.

Today, the risk of melanoma metastases is assessed, especially after the cancer has been removed, by analysing certain characteristics such as thickness and the presence of ulceration under a microscope. These parameters remain fundamental, but they do not always allow to accurately identify patients who will have a recurrence or develop metastases.

This is why an international research team coordinated by Aristotle University of Thessaloniki decided to look at another source of information: dermatoscopic images, i.e. ‘enlarged photos’ of melanoma taken before surgery. The study, which involved ten specialist centres on three continents and over 500 patients, collected nearly 800 images. Thirty experienced dermatologists have examined them, describing colours, structures and other visible signs on the lesion in a standardised way.

At this point, the researchers put together all the observations and analysed them in relation to the evolution of the disease over time. It turned out that some recurring details in the images really make a difference. When melanoma has extensive ulceration, i.e. areas where the surface of the skin appears ‘broken’, and the so-called ‘blue-white veil’, the risk of metastasis is higher and the likelihood of remaining free of recurrence over time is lower.

On the contrary, in cases where the lesion shows very intense pigmentation and signs of regression – small scarring areas indicating a reaction of the immune system against the tumour – the behaviour of the disease tends to be less aggressive, with a lower probability of spreading to other organs.

Based on these signs, the international team built three tools to estimate the risk of metastasis: one that uses only dermatoscopic images, one that relies on traditional histological data, and one that combines both information. The most interesting result is that the model based only on the dermatoscope showed a predictive capacity comparable to that of histological parameters. The combination of the two approaches is the best performing.

Looking ahead, this means that the dermatoscope – already indispensable for the early detection of melanoma – could also become a tool for estimating the aggressiveness of the tumour in advance, even before surgery. This would allow for more targeted monitoring and more personalised treatment choices, for example to decide who will need additional treatments or closer monitoring.

The authors note, however, that this is a retrospective study and that the results will have to be confirmed by new research on even greater numbers of patients before entering clinical practice.

Prof. Iris Zalaudek, professor of Cutaneous and Venereal Diseases at UniTS and head of the Department of Dermatology and of the Sexually Transmitted Diseases and HIV centres at the local health services (ASUGI), argues that ‘the results of the study support the notion that the standard in the melanoma treatment must be an accurate clinical and dermoscopic documentation of the first stages. Dermatoscopy has the potential to act as an additional non-invasive prognostic tool for melanoma, providing valuable information on the biological behaviour of the tumour before excision.’

‘This approach,’ concludes Zalaudek ‘could improve patient risk stratification and support decision-making on adjuvant and neoadjuvant treatments’.