What should you know about malignant melanoma on the foot?

Foot melanoma may develop on skin that receives little sun, including the sole, heel, sides of the foot, or spaces between toes. It can be brown, black, tan, or unevenly coloured, and may have an irregular edge or several shades. Under a toenail, it may form a widening stripe or pigment that extends onto nearby skin. A sore that does not heal, bleeding, crusting, or a firm new lump also deserves attention. These changes can have harmless explanations, so appearance alone cannot confirm melanoma; diagnosis requires a clinician’s examination and often a biopsy.

Arrange a dermatology appointment if a foot or nail mark is new, changing, darkening, enlarging, or different from your other marks. Take a clear photograph beside a ruler and note when you first noticed the change, but do not delay care while monitoring it. The clinician may inspect the entire skin surface and feel nearby lymph nodes. If melanoma is suspected, removal of the concerning area for laboratory examination helps establish the diagnosis. Treatment depends on the tumour’s depth, location, and whether it has spread; options may include surgical excision, wider skin cancer surgery, or other specialist treatment.

Book an assessment promptly for rapid change, persistent bleeding, an ulcer, increasing pain, or a lesion that catches on footwear. Seek urgent medical help for uncontrolled bleeding, spreading redness with fever, severe swelling, or sudden difficulty walking. If melanoma has already been diagnosed, new headaches, weakness, confusion, seizures, breathlessness, or unexplained persistent pain should be reported quickly because they may signal a complication requiring urgent review.

Ask whether the mark needs a biopsy, how much tissue may need removal, whether nearby lymph nodes require assessment, and how the result will guide treatment. Clarify wound care, footwear and walking restrictions, pathology timing, and the schedule for follow-up after cancer treatment.