Subungual Melanoma: Symptoms, Causes, Treatment

What are the symptoms of subungual melanoma?

Subungual melanoma is a rare type of melanoma that occurs under the nail. The symptoms can vary, but common signs include:

Dark Stripes or Streaks: One of the most noticeable symptoms is a dark stripe or streak beneath the nail, which may be brown or black and can appear to widen over time.
Changes in Nail Color: The affected nail may change color, becoming darker or showing areas of pigmentation that differ from the surrounding nail.
Nail Deformation: The nail may become deformed, thickened, or brittle. It might also show unusual ridges or grooves.
Splinter Hemorrhages: Small, dark lines or spots that resemble splinters can appear under the nail.
Nail Separation: The nail may separate from the nail bed, which can cause pain and discomfort.
Swelling or Tenderness: The area around the nail may become swollen or tender, and there may be pain in the affected finger or toe.
Ulceration: In more advanced cases, the area under the nail may develop an ulcer or open sore.

If you notice any of these symptoms, it’s important to seek evaluation by a healthcare professional, as early detection and treatment are crucial for managing subungual melanoma.

What are the causes of subungual melanoma?

The exact causes of subungual melanoma are not fully understood, but several factors are believed to contribute to its development:

Genetic Factors: A family history of melanoma or other skin cancers can increase the risk of developing subungual melanoma. Genetic mutations and hereditary conditions may play a role in predisposition.
Sun Exposure: Although subungual melanoma occurs under the nail and is less directly related to sun exposure, general ultraviolet (UV) radiation exposure can increase the risk of various types of melanoma, including those in less exposed areas.
Trauma: Chronic trauma or injury to the nail area might be associated with an increased risk, though this is not always the case. Repeated trauma to the nail bed can sometimes lead to changes in nail appearance that may mimic or mask melanoma.
Pigmented Lesions: The presence of a pigmented lesion or mole under the nail may increase the risk. Such lesions should be monitored for changes in color, size, or shape.
Immune System Factors: Individuals with weakened immune systems, whether due to medical conditions or medications, may have a higher risk of developing melanoma.
Ethnic Background: Subungual melanoma is more commonly observed in individuals with darker skin tones, although it can occur in people of any ethnicity.
Atypical Mole Conditions: Having atypical or dysplastic nevi (moles) can be a risk factor, as these moles may have a higher likelihood of becoming cancerous.

While these factors can contribute to the development of subungual melanoma, it’s important to note that not all cases will have an identifiable cause. Regular monitoring of changes in the nails and seeking medical evaluation for any unusual symptoms are key to early detection and treatment.

What is the treatment for subungual melanoma?

Treatment for subungual melanoma typically involves a combination of surgical and supportive approaches, depending on the stage and extent of the disease. The main treatment options include:

Surgical Excision: The primary treatment for subungual melanoma is surgical removal of the affected nail, nail bed, and surrounding tissue. The goal is to remove all cancerous cells and ensure clear margins. In some cases, a wider margin of healthy tissue may be removed to reduce the risk of recurrence.
Sentinel Node Biopsy: If the melanoma has spread to nearby lymph nodes, a sentinel node biopsy may be performed. This procedure involves removing and examining the first few lymph nodes that drain the area around the melanoma to check for cancer spread.
Wide Local Excision: For more advanced cases, a wider excision of surrounding tissue may be necessary to ensure all cancerous cells are removed.
Reconstructive Surgery: After the removal of the melanoma, reconstructive surgery may be needed to repair the nail bed and surrounding area, depending on the extent of the surgical excision.
Adjuvant Therapy: For cases where the melanoma has spread or is at high risk of recurrence, additional treatments such as immunotherapy or targeted therapy may be considered. These therapies help to boost the immune system or target specific cancer cells.
Radiation Therapy: In some cases, especially if the melanoma has not responded well to surgery or has spread, radiation therapy may be used to target and destroy remaining cancer cells.
Regular Follow-Up: Ongoing monitoring and follow-up care are crucial to detect any recurrence or new developments early. This includes regular skin exams, imaging studies, and possibly additional biopsies.

Treatment plans are personalized based on the individual’s specific condition, including the stage of the melanoma, overall health, and response to initial treatments. Early detection and intervention are essential for the best outcomes.

What is the survival rate for subungual melanoma?

Subungual melanoma is a rare form of melanoma that occurs under the nails, most commonly affecting the fingernails or toenails. The survival rate for subungual melanoma varies depending on several factors, including the stage at which the cancer is diagnosed, the depth of the tumor (Breslow thickness), and whether the cancer has spread (metastasized) to other parts of the body.

General Survival Rates:

Early Stage (Localized):
When subungual melanoma is detected early and is confined to the area under the nail without spreading to lymph nodes or other organs, the 5-year survival rate can be quite favorable, often around 80-90%. Early-stage detection typically involves a thinner tumor, which is associated with better outcomes.
Regional Spread (Stage III):
If the melanoma has spread to nearby lymph nodes or tissues, the 5-year survival rate decreases. For stage III melanoma, the survival rate generally ranges from 45-70%, depending on the extent of the spread and the number of affected lymph nodes.
Distant Spread (Stage IV):
If subungual melanoma has metastasized to distant organs (such as the lungs, liver, or brain), the 5-year survival rate drops significantly, typically ranging from 15-25%. Stage IV melanoma is more difficult to treat and is associated with a poorer prognosis.

Factors Influencing Survival:

Breslow Thickness: The thickness of the tumor measured from the top of the epidermis to the deepest point of the tumor. Thinner tumors are associated with better survival rates.
Ulceration: The presence of ulceration (a break in the skin over the melanoma) is a sign of a more aggressive tumor and is associated with a lower survival rate.
Lymph Node Involvement: If melanoma cells have spread to nearby lymph nodes, the prognosis is less favorable.
Patient’s Overall Health: The patient’s general health and the presence of other medical conditions can also impact survival.

Importance of Early Detection:

Early detection and treatment are crucial for improving the survival rate of subungual melanoma. Because it is often mistaken for a benign condition like a bruised nail or fungal infection, subungual melanoma is sometimes diagnosed at a later stage, which can negatively impact survival.

Regular self-examination of the nails and prompt evaluation of any suspicious changes (such as a dark streak, discoloration, or a nail that does not heal) by a dermatologist can lead to earlier detection and better outcomes.