Malignant skin lesions and tumours, commonly referred to as skin cancers, represent the most prevalent cancer type in the population. This prevalence stems from skin being the body’s largest organ, constantly exposed to carcinogens including ultraviolet radiation and environmental chemical agents.
Three major skin cancer categories exist: basal cell carcinomas (BCC), squamous cell carcinoma (SCC), and melanoma. The first two are grouped as non-melanoma skin cancers. Additional rare types include Merkel cell tumours and dermatofibrosarcoma protuberans.
Basal cell carcinomas and squamous cell carcinomas comprise the vast majority of skin cancers. While malignant, these typically remain localized. Untreated SCC demonstrates greater propensity for spreading than BCC.
A smaller yet significant proportion of skin cancers involve malignant melanomas. This highly aggressive cancer readily metastasizes to distant sites and can prove fatal without early intervention.
Skin cancers frequently originate from precancerous lesions — skin changes that aren’t cancerous but may progress to cancer over time. Medical professionals term these changes dysplasia.
Actinic Keratosis
This presents as a red or brown, scaly, rough skin area potentially developing into squamous cell carcinoma or basal cell carcinoma, primarily appearing in sun-exposed regions.
A nevus represents a mole, while abnormal moles are termed dysplastic nevi. These may eventually transform into melanoma.
Early identification of malignant or precancerous lesions proves critical, as complete excision during early stages cures nearly all skin cancer cases.