Squamous Cell Carcinoma
This is the most common form of cancer in the feet. This particular skin cancer may appear as a scaly bump or plaque and may often appear inflamed and be painless or itchy. Because of its often skin-like growths, it may be confused with a callus, wart, fungal infection or ulceration. This may also resemble psoriasis and dermatitis and may occur on sun-exposed areas.
Basal Cell Carcinoma
These lesions are less common in the feet and occur typically in sun-exposed areas. This is the least aggressive of the skin cancers and damage is relatively confined to the skin and rarely spreads. Lesions with crusting, oozing, lack of healing or itching should be biopsied. These lesions may resemble ulcerations or non-healing sores.
Malignant Melanoma
This is the most lethal and deadliest of skin cancers in the foot and leg. Survival is based on early detection. Because they can mimic benign moles, skin lesions with change in color or irregular borders or greater than 6 mm should be biopsied. These may be found in sun exposed areas such as the top of the foot but also on soles of the feet and new lesions in non-sun-exposed areas like the soles should be suspect. Similar to squamous cell carcinomas, they can be mistaken for common warts and ulcers. Surgical treatment may require wide excision of the skin lesion and may entail additional consultation for lymph node biopsy and plastic surgery.
Characteristics of Skin Cancer – (Think A-B-C-D-E!)
Asymmetry – When a skin lesion is cut in half it should appear equal on both halves and should match. If it does not, then biopsy is recommended.
Borders – The edges of a skin lesion should be even. If the edges are ruffled, ragged or scalloped, then it should be biopsied.
Color – The skin lesion should have one consistent color. Lesions with multiple color are suspect.
Diameter – Lesions greater than the size of an eraser head (5mm) should be suspect.
