Cutaneous Melanoma is one the most deadly of all malignancies. It accounts for only 4% of all cancer cases but is responsible for 79% of all skin cancer-related deaths. The rapid increase in the incidence of melanoma in the U.S. is alarming. There were approximately 68,130 new cases in the U.S. in 2010 and 8,700 deaths from melanoma in 2010.

Risk Factors: 

Ultraviolet light (UV) exposure is by far the biggest risk factor for developing melanoma.  Sunshine contains UV radiation.  Tanning beds also produce UV light.  Increased exposure to UV light over time increases the risk of developing melanoma because the UV rays cause DNA damage.  Years of sun exposure (or less in the case of tanning beds) can cause DNA damage to accumulate to the point where the melanocytes are irreversibly harmed leading to melanoma.  Other risk factors include moles (dysplastic nevi syndrome), personal or family history of melanoma, fair hair and light skin, as well as age and gender (males are more likely to get melanoma).

Preventive Measures:

The avoidance of sunburn,  minimizing cumulative sun exposure, and the avoidance of tanning beds are effective measures in skin cancer prevention. The best approach to melanoma remains early detection. Surgical resection of localized cutaneous melanoma is usually curative. If melanoma metastasizes to regional lymph nodes or distant sites the medial survival may drop to a few years or a matter of months.

Diagnosis:

Everyone should do periodic self exams including the palms, soles, nails, scalp and back.  Any suspicious lesions should be looked at by a health care professional.  A good rule to follow is the ABCDE rule: 

A-asymmetry (asymmetric lesions are those were one half of the mole does not match the other)

B-border (look for lesions with irregular borders)

C-color (lesions that are changing in color should be evaulated)

D-diameter (lesions increasing in diameter or those greater than the size of a pencil eraser should be evaluated)

E-evolving (again, any lesion that is changing over time should be evaluated and removed)

Other warning signs to look for include scaling, itching, oozing, bleeding, or ulceration of a lesion.  Although most melanomas are pigmented (brown/black/blue), some have no pigment and may be a light color.  A lesion suspicious for melanoma should be excised with a thin margin to provide optimal evaluation. If a lesion is too large to adequately excise and close the skin, then a portion of the lesion should be biopsied.

Treatment:

Thirty years ago, melanomas were widely excised with 3cm to 5 cm margins and routine elective lymph node dissection (ELND) performed resulting in great morbidity for patients. Because of decades of research, dramatic changes have occurred in the surgical strategies for management of melanoma. Large clinical, prospective, randomized trials have shown little or no benefit to wide margins and have not confirmed an overall survival benefit to routine ELND. The margins (amount of uninvolved skin around the melanoma) that are taken when a melanoma is excised depends on the thickness of the melanoma.  Adequate margins to minimize the risk of local recurrence are as follows:

Tumor thickness (Breslow)       Margin

≤ 1 mm                                      1 cm

1-2 mm                                     1-2 cm

> 2 mm                                      2  cm

At the time of examination, your surgeon will examine the lymph nodes closest to the melanoma.  If any feel suspicious, a fine needle aspiration biopsy or excisional biopsy will be performed to evaulate for spread to that lymph node.  If that node is involved, then a lymph node dissection is usually done.  A sentinel lymph node biopsy is usually done on all melanomas over 1mm thick to evaluate for micrometastasis that cannot be felt on exam.  The status of the first lymph nodes draining the primary tumor, also called the sentinel lymph node (SLN) is found to be the most powerful prognostic factor in patients who have early stage melanoma.

The SLN concept proposes that lymph node drainage from a tumor passes first to a SLN before passing to other nodes in the regional node field. The SLN status accurately reflects the status of the entire lymph node field in patients with melanoma. If the SLN is free of metastatic disease it is rare to have metastases in other lymph nodes in that lymph node field.

There is a dramatic difference in five year survival probability based on the status of the SLN. Patients with negative SLN’s have a 90% chance of survival at five years vs. 56% chance for positive SLN patients. Overall, only approximately 20% of SLN’s are positive for metastatic disease. It is currently recommended that those patients have a complete lymph node dissection in the affected lymph node field.

Advanced stages of melanoma are treated in a multi-modality approach including surgery, chemotherapy, immunotherapy, and radiation therapy. 

The surgeons of Capital Surgical Clinic are experienced in the treatment of melanoma including sentinel lymph node biopsy.  For more information about melanoma and sentinel lymph node biopsy for melanoma, please visit one of these trusted sites: