In a doctoral thesis carried out in our department in 1997, the frequency of melanoma in Catalonia was 5 per 100,000 inhabitants. Today these figures are not valid since the number of cases is multiplied by three every five years. In 2007, we detected 22 cases in our service and in 2012, already 66.
The risks of moles depend on several factors: whether they are congenital or acquired, the size of the mole, the age of appearance and family or personal history, among others. In the case of children, the probability of malignancy is very rare, but it is not without risk. Congenital nevi, which appear at birth and grow with the child’s development, can vary in size from 1.5 cm to 20 cm. The risk increases with size, so they should be monitored periodically. Acquired nevi have a higher risk and will depend on the different clinical presentations.
Congenital nevi
Nevi, when giant, represent a congenital error in embryonic ectodermal development and can affect the brain and spinal cord. They are asymptomatic in the first years of life and may manifest themselves later with symptoms of cranial hypertension, such as vomiting, headaches, etc.
The big problem we detect in this type of nevus is melanophobia, which we used to transmit because we did not have the current methodology. Nowadays, we can avoid it thanks to the new imaging techniques and the greater clinicopathological knowledge. In a small percentage the histopathological diagnosis is difficult, requiring a second opinion by an expert in dermatopathology.
There are many differential situations that are difficult to interpret, such as pigmented lesions in hormonal areas (vulva and mammary region), lesions on palms and soles, recurrent nevi after previous treatments, dysplastic nevi that simulate melanomas, non-pigmented melanomas that are confused with banal lesions, which always require histopathological examination.
Current lines
The objective now is to promote early diagnosis with which we will achieve cure in most cases, the examination of the entire body surface without forgetting hidden areas such as the scalp, nails and mucous membranes. Prevention is important by eliminating risk factors such as aggressive and intermittent sun exposure (vacations) and the use of sunbeds. We want to give information of optimism in both diagnostic advances and treatments, since there is a percentage of melanomas with genetically determined metastases that are curable. A few years ago we could not give this good news.
Exhaustive control of nevi
Our residents are confronted every day during their training with situations of great responsibility. They recognize those nevi at risk by their clinical characteristics: size, asymmetric irregularities in shape, change in coloration, which they visualize with an epiluminescence loupe that they always carry with them, and they biopsy the entire lesion in suspicious ones. In our institute we use computerized digitalization that detects any change in the annual revisions.