Melanoma of the Head and Neck
What is Cutaneous Melanoma?
Melanoma is the most dangerous form of skin cancer. It arises when pigment-forming cells, called melanocytes, in the basal layer of the skin sustain genetic alterations that cause these cells to multiply in an uncontrolled manner. The most common cause of these genetic alterations is extensive exposure to the ultraviolet radiation from the sun or from tanning booths.
In addition to multiplying in an uncontrolled manner, these altered melanocytes can invade deep into the underlying tissue and spread (metastasized) to other parts of the body including sites like lymph nodes, the lungs, the liver, bone, and the brain. When melanoma is detected early (stage I or II) and treated, it is very curable. However, if it has metastasized to lymph nodes (stage III) or to distant sites (stage IV), it can be fatal.
Multidisciplinary Pigmented Lesion and Melanoma Clinic
Our division works very closely with the Dermatologists, Medical Oncologists, and General Surgeons in a multidisciplinary clinic at 900 Blake Wilbur Drive. Because our physicians have simultaneous clinics, new patients are evaluated by multiple physicians – all at the initial visit – making it possible to expedite the discussion and rendering of a treatment plan. Furthermore, subsequent follow-up visits can be coordinated in a manner that allows multiple appointments with all of the relevant treating physicians on the same day.
Surgery for Early Stage Head and Neck Melanoma
Melanoma arising in areas of the head and neck are initially treated by surgeons in the Division of Head and Neck Surgery, and those arising on the extremities or trunk are treated by surgeons in General Surgery.
For patients with melanoma that have no clinical evidence of spread to lymph nodes, a wide excision of the melanoma tumor is recommended. The size of the excision (or size of the margin of normal skin around the lesion) is determined by the thickness of the melanoma. In some cases, it will be possible to repair the area where the excision is performed by using techniques to rotate in skin. In other cases, a skin graft may be required.
For melanomas that are greater than 1 mm in thickness or for thinner melanomas with certain adverse pathologic features, it may be recommended that a lymph node sampling be performed. This is a procedure called a “sentinel lymph node biopsy,” and it utilizes a short-acting radioactive tracer that is injected around the perimeter of the melanoma to localize the draining (sentinel) lymph node(s). The tracer is taken up by the lymphatic vessels in the skin and then migrates to the sentinel node(s) and can be detected by specialized imaging techniques (lymphoscintigraphy and SPECT/CT) that are performed by our colleagues in the Nuclear Medicine division of the Department of Radiology.
In the operating room, the node that has collected the radioactive tracer is removed and sent to the Division of Dermatopathology in the Department of Pathology, where it will be assessed over the next several days for any microscopic spread of the melanoma to the lymph node.
If the node is positive for melanoma metastasis, a comprehensive lymph node removal may be recommended, since a Phase III clinical trial has demonstrated a survival benefit to having early removal of these lymph nodes. In addition, adjuvant systemic treatment may also be recommended, and this will be determined during a discussion between the patient and the medical oncologists after the comprehensive lymph node removal is performed.
Compared to melanomas of other parts of the body, melanomas arising in the head and neck region tend to have a more aggressive clinical course. In addition, it is more difficult to accurately identify the sentinel lymph node in the head and neck regions, given the more varied drainage patterns, the anatomy, and the closer proximity of the sentinel node to the primary tumor site (resulting in “shine-through” artifact from the tracer injection sites). As such, the false-negative rate is significantly higher than that of sentinel lymph node biopsy attempts for primary melanomas on the extremities. For this reason, our team includes head and neck surgeons highly experienced in these lymph node sampling techniques.
Surgery for Advanced Stage Head and Neck Melanoma
For patients with clinical evidence of metastases of their melanoma or with recurrent disease, staging with imaging studies will be performed. If the metastasis is relatively contained, the patient will be evaluated for surgical resection. This may involve removal of lymph nodes and one of the major salivary glands. Our surgeons work closely with the head and neck neuroradiologists for surgical planning and with the medical oncologists for subsequent adjuvant treatment planning.
Mucosal melanoma is a rare form of melanoma that affects the upper aerodigestive tract, including the oral cavity, the nasal passages, and the sinuses. They account for less than 1% of all melanomas, and due to their rarity, this disease is not as well understood as cutaneous melanoma. In general, mucosal melanoma behaves very aggressively, often metastasizing to regional lymph nodes and distant sites. The surgery that is required is tailored to the location of the melanoma and will usually include lymph node removal at the time of surgery.