Acral lentiginous melanoma or ALM is a type of skin cancer. It is often misjudged and goes unnoticed until the cancer cells have progressed. ALM develops on the hands (palms) and soles of your feet. About 1-3% of the people detected with melanoma develop ALM. This type of skin cancer targets white complexioned people and black-skinned people equally. Again like many other cancers, it is difficult to diagnose ALM. Treatment is by surgical excision of the lumps and sometimes other methods are also used. Prognosis and survival depends on the extent of progress of the disease. ALM can occur on the normal skin and also on the existing mole.
ALM starts slowly as a flat patch on the skin or on the mole. Initially malignant (cancerous) cells remain restricted with the tissue or epidermis. It can be in-situ for weeks together or even months. But gradually the melanoma cells spread deep into the skin invading other areas nearby and even the lymph nodes.
Who Are At Risk ?
ALM is a rare type of skin cancer and it has no bar against color of the skin. It targets white and dark skinned people equally and sometimes black skinned people are at high risk. ALM occurs equally in men and women and adults above 45 years are the target.
Exact cause of the occurrence of ALM is not known. Repeated mutation of DNA is known to cause melanoma. Progressive sun exposure can intensify formation of moles and sunburn.
ALM occurs as red or brownish pigment on the skin and often it occurs on the palms of your hands or soles of the feet. It occurs largely on the extremities of the body. Acral lentiginous melanoma initially appears as a stain on the skin color and gradually increases in size and shape. ALM moles are asymmetric in shape, without defined border and it is changing in color and the diameter of mole is roughly the size of pencil eraser.
The size of melanoma can range above 6 mm in diameter and is often seen in mixed color or varying colors like bluish grey, brownish blue and reddish brown etc. It resembles ulcer or big bumps on the skin and may sometimes bleed. The tumor like cells is thick in pigment and grows in size on time.
The cells of melanoma of ALM go unnoticed until it becomes bigger in size. Dermatologist can detect cancer during examination. Biopsy is done to confirm the analysis. A tissue sample from the mole is taken and tested under a microscope. It shows positive report for BRAAFF test and if closely observed, melanoma can be detected by ABCDE rule. Once the cancerous cells starts metastasizing it becomes difficult to treat and fully cure ALM like many other cancers. Complete recovery is possible during the initial stages.
Breslow thickness and Clark level of invasion rating is used for determining the stage of melanoma.
- In level 1, melanoma is in-situ (in the same location)
- In Level 2, the cancer cells would have occupied papillary dermis. In the next level of 3, the cells would have invaded reticular dermis and in the level 4 and 5, it would have spread to subcutaneous tissue and nearby lymph nodes.
It is better to prevent melanoma than to treat it.
- In the phase 1 and 2 when the moles are thin it can be surgically excised and removed. Follow up is to be done at regular intervals to check that the cancer cells are not growing again.
- When it comes to stage 3 or 4, treatment is difficult. Cancer cells would have spread to nearby lymph nodes and even to other organs.
- Surgery is done for removing the nodes that are involved causing more complications.
- Minor amputation of the nail and soles are done for subungual lesions. The surgeon would try his best to save the ball of the foot. The entire (affected) finger or toes is removed along with lymph nodes to increase the survival rate.
- Laser and cryo therapy is done for ALM. Additionally topical steroids are also given. Removal of nodes is considered only if the cancer cells have metastasized and spread to other organs.
- Other forms like chemo and radiation are to be done in severe cases. Immunotherapy and target therapy are some kinds of treatment for ALM.
- Self skin examination and routine checkups are to be done for monitoring the condition of the patient after surgery.
Rate Of Survival :
Stage and extent of cancer decides the rate of survival in any type of cancer. Prognosis is good if the cancer is detected early and treated soon. Depth of the tumor and extent of spreading can reduce the survival rate.