Changes in your nails can be scary. Sometimes, a discolored nail is simply a sign of something harmless, like a bruise under the nail or a fungal infection. But, nail changes can also be a sign of something more serious, like melanoma.
This article will help you tell the difference between a subungual hematoma (a bruise under the nail) and nail melanoma. It’s important to be able to tell the difference because the earlier you catch melanoma, the better.
A subungual hematoma is usually caused by some kind of injury to the nail. The injury causes blood to collect under the nail plate. Nail melanoma, on the other hand, is a rare and aggressive form of skin cancer that develops in the nail matrix.
Here’s what to look for.
What Is a Subungual Hematoma?
A subungual hematoma is just a collection of blood under your toenail. Usually, it’s caused by some kind of injury to the toe.
You may get a subungual hematoma from:
- Stubbing your toe
- Dropping something heavy on your foot
- Wearing shoes that are too tight
These injuries cause bleeding under the nail, which becomes trapped. Because the blood has nowhere to go, you might experience throbbing pain right away.
Other symptoms of a subungual hematoma include:
- Reddish or purplish color under the nail right after the injury
- The color will eventually turn dark blue or black
- The nail may separate from the nail bed
Diagnosis and Treatment
Doctors can usually diagnose a subungual hematoma just by looking at it. They may drain the blood to relieve pressure and pain. This is called trephination.
Other treatments include:
- Rest, ice, elevation, and compression (RICE) if the hematoma is minor
- Nail avulsion (removal) may be necessary if the hematoma is large or the nail is severely damaged
Nail melanoma: What to know
Nail melanoma, also called subungual melanoma, is a rare and aggressive kind of skin cancer that begins in the nail matrix, the area where new nail cells are made. Melanoma under the nail accounts for less than 4% of all melanomas.
Most of the time, melanomas show up on the thumbnail or big toe. In fact, 75% to 90% of nail melanomas occur on those nails.
What causes nail melanoma?
Unlike skin melanomas, melanomas under the nail don’t have a strong connection to sun exposure. Instead, they may occur because of:
- a prior injury to the nail
- a family history of melanoma
- certain genetic mutations
Nail melanoma is more common in people of color, possibly because melanomas are less common on the skin of these populations.
What are the symptoms of nail melanoma?
The symptoms of nail melanoma can be subtle, but they’re important to recognize.
Symptoms may include:
- a dark streak or spot on the nail that doesn’t fade over time
- the streak may get wider or spread to the skin around the nail (known as Hutchinson’s sign)
- nail dystrophy (the nail becomes distorted, thin, or cracked)
- bleeding or ulceration around the nail
- pain around the nail
Subungual Hematoma vs. Nail Melanoma: What’s the Difference?
It can be tricky to tell the difference between a subungual hematoma and nail melanoma. Here are some key differences to look for:
Cause
- Hematoma: Usually caused by a specific injury, like stubbing your toe.
- Melanoma: May have no apparent cause, or it may be associated with a past injury that didn’t directly cause the melanoma.
Appearance
- Hematoma: Starts as a uniform color, then gradually fades and moves outward as the nail grows.
- Melanoma: Has irregular coloring and may get wider or darker over time. It can also affect the skin around the nail.
Growth Pattern
- Hematoma: Stays in one spot and gradually disappears.
- Melanoma: Expands and may cause the nail to change shape.
Pain
- Hematoma: Usually painful right after the injury, but the pain goes away over time.
- Melanoma: May or may not be painful.
The “ABCDEs” of Nail Melanoma
Dermatologists use the “ABCDEs” to help identify melanomas. Here’s how the ABCDEs apply to nail melanomas:
- Asymmetry: The discoloration isn’t uniform.
- Border: The edges of the discoloration are irregular or not clearly defined.
- Color: There are multiple shades of brown, black, or even no color at all (amelanotic).
- Diameter: A spot that’s widening beyond 3 millimeters (mm) could be a sign of melanoma.
- Evolution: The spot is changing in size, shape, or color.
How is nail melanoma diagnosed and treated?
If your doctor suspects you might have nail melanoma, they will use a variety of tools to make a diagnosis. Then, they’ll recommend a course of treatment.
Diagnostic Procedures
- Dermoscopy: Your doctor will use a dermatoscope to examine your nail and the skin around it. A dermatoscope is a handheld tool that provides a magnified, well-lit view.
- Biopsy: A biopsy is the only way to know for sure if you have melanoma. The doctor may take a sample of the nail matrix (the area where the nail grows from) or remove the entire nail.
- Imaging: If melanoma is confirmed, imaging tests like X-rays, CT scans, or MRIs may be used to see if the cancer has spread to other parts of your body (metastasis). A lymph node biopsy may also be performed to check for cancer cells.
Treatment Options
The main goal of treatment is to remove the melanoma and prevent it from spreading.
- Surgical Excision: This is the primary treatment. The amount of tissue removed depends on the stage and location of the melanoma. In some cases, Mohs micrographic surgery (a precise technique that removes the cancer layer by layer) may be used.
- Amputation: In advanced cases, where the melanoma has spread deeply or is located in a difficult-to-reach area, amputation of the toe or finger may be necessary.
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Adjuvant Therapies: These therapies are used in addition to surgery to kill any remaining cancer cells or prevent the melanoma from returning. They may include:
- Radiation therapy
- Chemotherapy
- Immunotherapy (especially for metastatic melanoma)
Frequently Asked Questions
What can be mistaken for toenail fungus?
Several conditions can mimic toenail fungus, including psoriasis, eczema, trauma to the nail bed (leading to a hematoma), and even nail melanoma. Some people might consider fake toenails for fungus as a way to hide it. Because appearances can be deceiving, and proper ICD-10 nail fungus coding is important, it’s always best to get a proper diagnosis from a doctor or podiatrist.
Is melanoma raised or flat?
Melanomas can be either raised or flat. Some start as flat, irregular spots and become raised over time. Others are raised from the beginning. Any new or changing growth on the skin or under the nail should be checked by a healthcare professional.
What does stage 1 nail melanoma look like?
Stage 1 nail melanoma is often characterized by a dark streak or band in the nail, usually wider at the base. It may also cause changes in the nail’s shape or texture. However, early melanomas can be subtle, so any unusual nail changes warrant prompt medical attention.
Can toenail fungus look like melanoma?
While toenail fungus and melanoma have distinct causes, in some cases, their appearances can overlap. Dark discoloration or thickening of the nail can be caused by either condition. It’s crucial to differentiate between them, as melanoma requires urgent treatment.
What is the difference between a hematoma and a melanoma toenail?
A hematoma is a collection of blood under the nail, typically caused by trauma, and often appears as a dark red or purplish spot that gradually grows out with the nail. Melanoma, on the other hand, is a form of cancer that can present as a dark streak or band in the nail that doesn’t fade or move with nail growth and may be accompanied by other nail changes. If you’re unsure, see a doctor for evaluation.
Putting It All Together
Subungual hematomas and nail melanomas can sometimes look alike, but they’re very different. Hematomas under the nail are common and usually harmless. Nail melanomas are rare but can be deadly.
Because of this, it’s important to pay attention to any changes in your nails and get them checked out by a doctor. Nail melanomas are easier to treat when they’re caught early.
Do regular self-exams of your nails, and if you see anything that worries you, make an appointment with a dermatologist right away.