Don't Be Misdiagnosed. Know the Signs of Toenail Melanoma

What You Should Expect For An Accurate Diagnosis and Effective Treatment For Subungual Melanoma

A dark spot or streak on your toenail could be a sign of subungual melanoma.  It's often slow and painless growth makes it tricky to catch early.  Learn the signs and when to seek urgent treatment.

We suspect melanoma from a pigmented spot that starts at the bottom of the nail next to the cuticle and makes a black streak on the toenail as it grows out toward the tip of the toe.

Sometimes you can have a discoloration of the nail fold at the proximal part of the nail and that discoloration of the skin is called a Hutchinson Sign.  Seeing Hutchinson Sign on your toenail is a good indicator that you may have a malignancy at the nail matrix.  

Melanoma of the nail unit usually affects the big toenail but any toenail may be involved.

• Sugungual melanoma orginates from the nail matrix
• Ungual melanoma originates from under the nail plate
• Periungual melanoma orginates from the skin beside the nail plate

It's often slow and painless growth make it tricky to catch.

Symptoms of Subungual Melanoma

• Over weeks to months the pigment band may become wider, especially at its base. 
• It usually becomes more irregular in pigmentation and can extend to involve the nail fold, known as Hutchinson Sign. 
• The pigmented lesion may ulcerate or bleed. 
• The nail bed will be painful.
• A nodule may develop under the nail plate, lifting it up.
• You may see a thinning, cracking or distortion of the nail plate.
• In many cases a subungual melanoma is not pigmented.

Diagnosis and Treatment Of Subungual Melanoma

In cases of suspected subungual melanoma you should expect your foot specialist to perform a simple surgical procedure called a nail matrix biopsy, right where the pigmented lesion is originating from.  A nail matrix biopsy is a full thickness biopsy through the nail plate and down to the nail bed. 

The specimen should then be sent to a certified pathology lab where the pathologist will look at the lesion under the microscope.  The lab should also perform a special staining technique to the sample lesion to determine if the growth is malignant, pre-malignant or benign.

If the diagnosis is melanoma of the nail unit then the definitive treatment is a digital amputation.  Melanoma is potentially life-threatening so if you have melanoma of the toe it needs to be dealt with aggressively.   You need a quick diagnosis and surgery to remove any chance of it spreading. 

When To See A Foot Specialist

Lesions that occur on the nail unit or the soles of the feet need to be watched carefully for malignant transformation (lesions changing in size or shape).

The bottom line -  if you have a pigmented streak or spot, on your toenail, underneath your toenail or on the nail fold beside your toenail, no matter what the color, you should have it evaluated by a specialist.  Little spots on little toenails could be signs of a big problem.