Squamous Cell Skin Cancer of the Head and Neck
What is squamous cell skin cancer of the head and neck?
Skin malignancies are the most common cancer in the United States, responsible for more than half of all new cancer cases. These can be broken down into melanoma and non-melanoma malignancies, which are squamous cell cancer and basal cell cancer. These skin malignancies are caused by ultraviolet radiation from exposure to the sun and tanning beds.
Squamous cell cancer is the second most common form of skin cancer. It is more aggressive and may require extensive surgery depending on location and nerve involvement. Radiation, chemotherapy and immunotherapy are used in advanced cases.
What are the symptoms of squamous cell skin cancer of the head and neck?
Squamous cell skin cancers usually present as an abnormal growth on the skin or lip. The growth may have the appearance of a wart, crusty spot, ulcer, mole or a sore that does not heal. It may or may not bleed and can be painful. If you have a preexisting mole, any changes in the characteristics of this spot — such as a raised or irregular border, irregular shape, change in color, increase in size, itching or bleeding — are warning signs. Pain and nerve weakness are concerning for cancer that has spread. Sometimes a lump in the neck can be the only presenting sign of skin cancer that has spread to lymph nodes, particularly when there is a history of previous skin lesion removal.
What are the risk factors for squamous cell skin cancer of the head and neck?
- Sun exposure.
- Tanning bed exposure.
- Fair skin.
- Age over 50 years.
- A history of skin cancer or precancerous skin lesions.
- A previous burn.
- Prior radiation to the head and neck area.
- Immunosuppression, either from a medical condition or by medications (such as those taken by transplant patients).
- Certain sun-sensitive conditions such as xeroderma pigmentosum.
How is squamous cell skin cancer of the head and neck diagnosed?
Diagnosis is made by clinical exam and a biopsy. Squamous cell cancers are staged by size and extent of growth. Squamous cell cancers can metastasize to nearby lymph nodes or other organs, and can invade both small and large nerves and local structures.
Biopsy can help determine if the squamous cell cancer is a low-risk tumor or a high-risk tumor that requires more aggressive treatment. Low-risk tumors are less than 10 millimeters in size, less than or equal to 5 millimeters deep and do not involve structures beyond the surrounding fat. High-risk tumors in the head and neck are those that involve the central face, nose and eye area, as well as those tumors that are greater than or equal to 10 millimeters on the cheeks, scalp and neck, tumors that are more than 5 millimeters thick or involve adjacent structures, tumors that invade nerves, tumors that are recurrent or arising from previously radiated tissue, and tumors arising in patients who are immunosuppressed.
Squamous Cell Skin Cancer of the Head and Neck Treatment
Surgery is the preferred management method for the majority of squamous cell skin cancers. Low-risk, early stage, small squamous cell cancers can be removed by Mohs surgery, which is a technique that spares normal tissue through repeated intraoperative margin testing, removing only the cancer and leaving adjacent normal tissue. Excision, curettage and desiccation, and cryosurgery can also be used to remove the cancer while sparing normal tissue. Radiation alone is an alternative for low-risk tumors when surgery is not desirable because of cosmetic concerns or medical reasons.
Large tumors and tumors with nerve or lymph node involvement are not suitable for Mohs surgery and require removal of at least 5-millimeter margins of normal tissue around the cancer and neck dissection for involved lymph nodes. Larger tumors require reconstruction, which can be done at the time of surgery if margin status is clear. Reconstruction should be staged when margins status is not clear.
Patients with high-risk tumors should meet with a radiation therapist to discuss postoperative radiation. Chemotherapy may be added to radiation for extensive lymph node involvement or positive margins that cannot be cleared with additional surgery. In patients with high-risk tumors who are not surgical candidates, systemic treatment with both radiation and chemotherapy is used. Such cases require multidisciplinary care by a team of surgeons, radiation oncologists and medical oncologists.
Recently, immunotherapy blocking the PD-1 receptor has been shown to be effective in patients with high-risk advanced squamous cell cancer of the skin that cannot be cured with surgery or radiation. Clinical trials of immunotherapy both before and after surgery and in patients with weakened immune systems are available at Johns Hopkins.