Melanoma — Serious Form of Skin Cancer

Melanoma occurs when genetic alterations cause melanocytes to proliferate uncontrollably, forming tumours. While most melanomas arise in areas of the skin exposed to ultraviolet radiation from the sun or tanning beds, they can also emerge in unexposed sites. These rarer presentations include acral lentiginous melanoma on the soles of feet or under nails, mucosal melanoma in mucous membranes, and uveal melanoma within the eye.

The disease is pathologically categorised by its depth of invasion, microscopic ulceration, and mitotic rate. The Breslow thickness, measuring tumour depth in millimetres, serves as a crucial prognostic factor. As malignant cells breach deeper dermal layers, they gain access to lymphatic channels and blood vessels, significantly increasing the risk of regional nodal spread and systemic metastasis.

A diagnosis of melanoma requires prompt and precise medical attention because tumour thickness directly influences outcomes. Understanding your melanoma stage helps doctors determine whether lymph node biopsies are necessary and whether preventative adjuvant therapies could reduce recurrence risk. Melanoma management has progressed rapidly, offering advanced targeted therapies and immunotherapies for patients with higher-risk or advanced disease. Knowing your exact diagnosis allows you to collaborate closely with dermatologists, surgical oncologists, and medical oncologists to choose the most effective, personalised treatment pathway for your health.

Melanoma is diagnosed via excisional skin biopsy and histological examination under a microscope. Key pathological features include Breslow thickness, ulceration status, and surgical margin clearance. For intermediate or thick lesions, sentinel lymph node biopsy is performed to assess micro-spread. Molecular biomarker testing evaluates genetic mutations, notably BRAF V600E/K mutations, as well as NRAS, KIT, and occasionally PD-L1 expression. Staging scans, such as whole-body PET-CT, brain MRI, or contrast-enhanced CT, assess whether melanoma cells have travelled elsewhere in the body.

Melanoma primarily affects cutaneous tissues, representing cutaneous melanoma. However, it can manifest in diverse biological subtypes that behave differently. Mucosal melanoma arises within mucous linings of the respiratory, gastrointestinal, and genitourinary tracts. Uveal melanoma affects the eye's iris, ciliary body, or choroid. Acral lentiginous melanoma develops on palms, soles, or nail beds, appearing independently of sun exposure and occurring across all skin tones. Rarer forms, such as amelanotic melanoma, lack visible pigment, occasionally leading to delayed clinical recognition.

Early-stage melanoma is primarily treated with wide local surgical excision to achieve clear margins. For stage III or high-risk disease, adjuvant immunotherapy (such as PD-1 checkpoint inhibitors) or targeted therapy combinations (BRAF plus MEK inhibitors) may be recommended to reduce recurrence risk. In metastatic or unresectable melanoma, systemic therapies—including dual immune checkpoint blockade or targeted small-molecule inhibitors—represent standard care. Radiation therapy is occasionally used for symptom management, brain metastases, or areas where complete surgical removal cannot be accomplished.