From the Guidelines
Melanoma typically develops over time, not suddenly, as a result of cumulative DNA damage from UV radiation exposure. This process usually occurs gradually, with changes in existing moles or the appearance of new skin growths happening over weeks to months or even years 1. While it might seem like a melanoma appeared suddenly, it was likely developing beneath the surface before becoming visible. The progression rate varies among individuals, with some melanomas growing slowly over years while others may evolve more rapidly over months.
Key Factors in Melanoma Development
- UV irradiation is a major carcinogen involved in melanoma genesis, causing a distinct DNA damage signature and a high rate of mutations per megabase (Mb) 1
- Prevention of UV exposure, including the regular use of sunscreen, has been shown to diminish the incidence of primary cutaneous melanomas in an Australian population 1
- Early detection significantly improves treatment outcomes, which typically involve surgical removal and possibly additional therapies like immunotherapy or targeted therapy depending on the melanoma's stage
Importance of Early Detection
Regular skin self-examinations are crucial for early detection, looking for changes in size, color, border irregularity, or asymmetry in moles. Diagnosis should be based on a full thickness excisional biopsy with a minimal side margin 1. Processing of the primary tumour according to international guidelines and by an experienced pathology institute is mandatory. Although older studies suggest the importance of follow-up to detect relapse and recognize additional skin tumors 1, the most recent and highest quality study emphasizes the need for prevention and early detection 1.
From the Research
Melanoma Development
- Melanoma develops as a result of several genetic alterations, with UV radiation often acting as a mutagenic risk factor 2.
- The exact cause of melanoma may not be fully understood yet, but there are some factors that initiate and promote this malignant process 3.
- Melanoma develops from a series of architectural and phenotypically distinct stages and becomes progressively aggressive culminating in metastasis 4.
Progression of Melanoma
- Melanoma may appear spontaneously (de novo melanoma) or on preexisting lesions (nevus-associated melanoma) 3.
- The disease progresses from an uncontrolled proliferation of melanocytes, which may initially form a benign lesion (nevogenesis), but in time, it may transition to melanoma 3.
- At the cellular level, deregulated homeostatic control in the skin microenvironment occurs through alterations in the expression of specific proteins, including growth factors and their receptors, adhesion molecules and their ligands, proteases and their substrates, and transcription factors and their target genes 4.
Time Frame of Development
- There is no clear indication that melanoma develops suddenly, as it is a result of several genetic alterations and progresses through distinct stages 2, 3, 4.
- The development of melanoma is a complex process that involves multiple factors and occurs over time, with some studies suggesting that intense exposures to UV radiation during early childhood may lead to melanoma in adults 4.