Subungual melanoma A cancer of skin under nail:
Introduction,Causes,Signs and Symptoms, diagnosis, Prevention :
Subungual melanoma is a serious type of skin cancer that occurs in the skin under your nails. Subungual melanomas are rare, seen in only 0.07% to 3.5% of the people in the world who have melanoma. But these melanomas can spread to other parts of your body and cause death.Subungual melanoma presents as brown-black discolorations of the nail bed. It can present as either a streak of pigment or irregular pigmentation. The discoloration can progress to thickening, splitting, or destruction of the nail with pain and inflammation.
Subungual melanoma is life threatening condition.
Subungual melanoma is rare, but it is deadly if left untreated.
It's is necessary to differentiate between the Toe nail melanoma and fungus.
Many people first mistake subungual melanoma as a bruise. However, unlike a bruise, the streaks from subungual melanoma do not heal or grow out with the nail over time. It can also be confused with normal pigmentation of the nail bed or a fungal infection.
When checking your nails for melanoma, dermatologists recommend looking for the following changes: A dark streak. This may look like a brown or black band in the nail — often on the thumb or big toe of your dominant hand or foot. However, this dark streak can show up on any nail.
Subungual melanoma often starts as a brown or black streak under a toenail or fingernail. A person may mistake it for a bruise. The main symptoms of subungual melanoma include: brown or black streaks in the nail without any known injury.
“You could have melanoma for a long time before you realize it, because some types are not so obvious. Some aggressive forms, like nodular melanoma, grow fast, are visible and can hurt or bleed.” While certain groups may be at a higher risk for melanoma, anyone can get the disease.
The difference between a subungual hematoma and a melanoma:
With a hematoma, pooling of blood in the nail bed usually occurs within a few days of a crushing injury. In contrast to melanoma, nail discoloration from hematoma will gradually clear as the nail heals. As the nail heals from a subungual hematoma, a transverse groove may form across its surface.
Subungual melanoma can be benign:
Subungual pigmentation can have benign and malignant etiologies. A common and important differential diagnosis is between subungual hematoma and subungual acrolentiginous melanoma.
Symptoms of subungual Melanoma:
In 75% to 90% of reported cases, subungual melanomas have been found in the thumb and the big toe. But they can be seen in other toes and fingers. And they can be quite painful.
Generally, subungual melanoma develops beneath the big toe, but it can sometimes affect your other toes. Its presentation can vary quite a bit. In some cases, it presents as band-like black discoloration on the affected nail, which later spreads.Subungual melanomas usually look like brown-black discoloration in the nail bed.
The discoloration may be in the form of a long, thin line, or streak, or it can be irregularly shaped. The discolored section of the nail can get thicker, split, or become damaged in some other way, to the point where it can’t be repaired.
Inflammation, a normal bodily process that fights infection or injury, can also be present. Chemicals released by the abnormal tissues cause white blood cells to start the repairing process. Sometimes the inflammation itself can become serious, putting your health at risk.
Prevention of subungual melanoma :
Since subungual melanoma isn’t caused by sun exposure, it can be difficult to prevent compared to other types of melanoma. General hand and foot health can be of some benefit, though.Be sure to protect your fingers and toes from injury during sports and other activities by wearing the right type of gear. You should also inspect these areas regularly for any unusual changes.
Diagnosis:
Nail biopsy for the diagnosis of nail melanoma:
Nail biopsy technique does not require anesthesia or hemostatic efforts. However, when a more proximal portion of the nail is required, the nail may be partially avulsed before the biopsy, which requires a digital block and hemostasis.
Biopsy of the nail bed can be performed with a punch or by an elliptical excision. The nail is usually avulsed prior to removing the specimen with a punch, although occa- sionally the punch can be taken through the nail plate us- ing a larger punch for the plate and a smaller punch for the nail bed specimen.
Most patients report throbbing pain in the first one to two days after the nail biopsy. This will decrease within a week. After the first week, the digit will still be tender to the touch. You may still have numbness and/or tingling at the biopsy site after a few weeks.
The sample is sent to a lab. There, it is placed in a special dish (culture). It is then watched to see if bacteria, viruses, or fungi grow. It may take up to 3 weeks to get results of a nail culture. Early diagnosis is essential to the successful treatment of subungual melanoma. It’s estimated that there is an average 5-year survival rate of 16 to 80 percent.This wide percentile is attributed to the timing of diagnosis and accounts for delayed diagnosis due to a variety of factors, including misdiagnosis.
Treatment of subungual Melanoma:
Subungual melanoma is treated surgically.The doctor will first remove your entire nail and then remove the growth. To date, surgery is the only viable treatment method for this type of melanoma.
With early treatment, the outlook is positive. Not only will your doctor remove the nail growth, but they can also help stop melanoma from spreading to other parts of the body.Subungual melanoma is treated surgically. Your doctor will first remove your entire nail and then remove the growth. To date, surgery is the only viable treatment method for this type of melanoma.
Once a doctor determines the severity of subungual melanoma, they will usually start treatment by surgically removing the affected area. This may include removing the entire nail or a portion of the digit.
If the cancer has spread to the lymph nodes or throughout the body, it may be too extensive to treat by just removing the affected area.
Following the surgical removal of the affected area, a doctor may recommend further therapies to help prevent the subsequent spread of the cancer. These treatments may include radiation and chemotherapy.
Foot melanoma is often treatable in the early stages. However, people will usually receive a diagnosis during the later stages, as the symptoms may not be easily noticeable. If foot melanoma spreads, or metastases, it can be life threatening. Foot melanoma most often initially spreads to the lymph nodes.
Information compiled by Dr. Bhairavsinh Raol
