Non-Melanoma Skin Cancer: Staging and Treatment

What is non-melanoma skin cancer?

There are two main types of non-melanoma skin cancer, named for the cells in which they start:

• Basal cell carcinoma (BCC)- Starts in basal cells.
• Squamous cell carcinoma (SCC)- Starts in squamous cells.

These non-melanoma skin cancers are found in the epidermis (the outermost layer of skin).

Other types of non-melanoma skin cancers are angiosarcoma, cutaneous B and T cell lymphomas, dermatofibrosarcoma protuberans, Kaposi’s sarcoma, Merkel cell carcinoma, and sebaceous gland carcinoma. This article will focus on basal cell and squamous cell carcinoma.

What is staging for cancer?

Staging is the process of learning how much cancer is in your body and where it is. Tests like a biopsy, chest x-ray, CT scan, MRI, and blood tests may be done to help stage your cancer. Your providers need to know about your cancer and your health so that they can plan the best treatment for you.

Cancer staging looks at the size of the tumor and where it is, and if it has spread to other organs. The staging system for non-melanoma cancer is called the “TNM system.” It has three parts:

• T-describes the size/extent of the tumor and if it has grown deeper into nearby structures or tissues, such as a bone.
• N-describes if the cancer has spread to the lymph nodes.
• M-describes if the cancer has spread to other organs (called metastases).

How is non-melanoma skin cancer staged?

Staging for non-melanoma skin cancer is based on:

• The size of your tumor and what is found after biopsy or surgery (if you have had surgery).
• Surgery to test if your lymph nodes have cancer cells.
• Any evidence of spread to other organs (metastasis).

The most recent version of the TNM system for non-melanoma skin cancer is only for squamous and basal cell skin cancers of the head and neck (lips, ears, face, scalp, and neck). There is a different staging system for non-melanoma cancer on the eyelid.

Most times, your provider will not need to know the staging of basal cell carcinoma. This is because these cancers are almost always cured before they can metastasize.

The staging system is very complex. Below is a summary of the staging. Talk to your provider about the stage of your cancer.

Basal cell and squamous cell carcinoma of the skin (on the head or neck, but not on the eyelid)

Stage 0 (Carcinoma in situ): Abnormal cells are found in the squamous or basal cell layer of the epidermis. These cells may become cancer and spread into nearby normal tissue. Stage 0 is also called carcinoma in situ.

Stage I: The tumor is 2 centimeters (cm) or smaller.

Stage II: The tumor is larger than 2 centimeters but not larger than 4 centimeters.

Stage III:

• The tumor is larger than 4 centimeters; OR
• The cancer has spread to tissue covering the nerves below the dermis, below the subcutaneous tissue, or to the bone and the bone has minor damage; OR
• The cancer has spread to one lymph node on the same side of the body as the tumor and the node is 3 centimeters or smaller, and cancer has not spread through to the outside covering of the lymph node; OR
• The tumor is 4 centimeters or smaller. Cancer has spread to one lymph node on the same side of the body as the tumor and the node is 3 centimeters or smaller.

Stage IV:

• The tumor is any size and cancer may have spread to the bone and the bone has minor damage, or to tissue covering the nerves below the dermis, or below the subcutaneous tissue. Cancer has spread to the lymph nodes as follows:
  • One lymph node on the same side of the body as the tumor, the affected node is 3 centimeters or smaller, and cancer has spread through to the outside covering of the lymph node; OR
  • One lymph node on the same side of the body as the tumor, the affected node is larger than 3 centimeters but not larger than 6 centimeters, and cancer has not spread through to the outside covering of the lymph node; OR
  • More than one lymph node on the same side of the body as the tumor, the affected nodes are 6 centimeters or smaller, and cancer has not spread through to the outside covering of the lymph nodes; OR
  • One or more lymph nodes on the opposite side of the body as the tumor or on both sides of the body, the affected nodes are 6 centimeters or smaller, and cancer has not spread through to the outside covering of the lymph nodes.
• The tumor is any size and cancer may have spread to tissue covering the nerves below the dermis, or below the subcutaneous tissue, or to bone marrow or to bone, including the bottom of the skull. Also:
  • The cancer has spread to one lymph node that is larger than 6 centimeters and cancer has not spread through to the outside covering of the lymph node; OR
  • The cancer has spread to one lymph node on the same side of the body as the tumor, the affected node is larger than 3 centimeters, and cancer has spread through to the outside covering of the lymph node; OR
  • The cancer has spread to one lymph node on the opposite side of the body as the tumor, the affected node is any size, and cancer has spread through to the outside covering of the lymph node; OR
  • The cancer has spread to more than one lymph node on one or both sides of the body and cancer has spread through to the outside covering of the lymph nodes.
• The tumor is any size and cancer has spread to bone marrow or to bone, including the bottom of the skull, and the bone has been damaged. Cancer may have also spread to the lymph nodes; OR
• The cancer has spread to other parts of the body, such as the lung.

Basal cell and squamous cell carcinoma of the skin on the eyelid

Stage 0 (Carcinoma in situ): Abnormal cells are found in the epidermis, usually in the basal cell layer. These abnormal cells may become cancer and spread into nearby normal tissue. Stage 0 is also called carcinoma in situ.

Stage IA: The tumor is 10 millimeters or smaller and may have spread to the edge of the eyelid where the lashes are, to the connective tissue in the eyelid, or to the full thickness of the eyelid.

Stage IB: The tumor is larger than 10 millimeters but not larger than 20 millimeters and the tumor has not spread to the edge of the eyelid where the lashes are, or to the connective tissue in the eyelid.

Stage IIA:

• The tumor is larger than 10 millimeters, but not larger than 20 millimeters and has spread to the edge of the eyelid where the lashes are, to the connective tissue in the eyelid, or to the full thickness of the eyelid; OR
• The tumor is larger than 20 millimeters but not larger than 30 millimeters and may have spread to the edge of the eyelid where the lashes are, to the connective tissue in the eyelid, or to the full thickness of the eyelid.

Stage IIB: The tumor may be any size and has spread to the eye, eye socket, sinuses, tear ducts, or brain, or to the tissues that support the eye.

Stage IIIA: The tumor may be any size and may have spread to the edge of the eyelid where the lashes are, to the connective tissue in the eyelid, or to the full thickness of the eyelid, or to the eye, eye socket, sinuses, tear ducts, or brain, or to the tissues that support the eye. Cancer has spread to one lymph node on the same side of the body as the tumor, and the node is 3 centimeters or smaller.

Stage IIIB: The tumor may be any size and may have spread to the edge of the eyelid where the lashes are, to the connective tissue in the eyelid, or to the full thickness of the eyelid, or to the eye, eye socket, sinuses, tear ducts, or brain, or to the tissues that support the eye. Cancer has spread to lymph nodes as follows:

• One lymph node on the same side of the body as the tumor, and the node is larger than 3 centimeters; OR
• More than one lymph node on the opposite side of the body as the tumor, or on both sides of the body.

Stage IV: The tumor has spread to other parts of the body, such as the lung or liver.

How is non-melanoma skin cancer treated?

Treatment for non-melanoma cancer depends on many things, like your cancer stage, age, overall health, and testing results. Your treatment may include some or all the following:

• Surgery.
• Radiation therapy.
• Chemotherapy.
• Targeted therapy.
• Immunotherapy.
• Clinical trials.

Surgery

Surgery is often used in the treatment of basal cell and squamous cell skin cancer. There are many different types of surgery that may be used. The surgery you have depends on the type and staging of your cancer, how large it is, where it is on the body, and other things like your overall health, and age. Most surgeries for non-melanoma skin cancer can be done in your provider’s office or in a clinic. Surgery is sometimes followed by chemotherapy and/or radiation therapy. Your provider will talk to you about which procedure(s) are best for you and your treatment plan.

Radiation Therapy

Radiation therapy uses high-energy x-rays to kill cancer cells. Radiation may be used as the only treatment or along with surgery and/or chemotherapy. Radiation is used as the main treatment for skin cancers that are very large, in an area that makes it hard to remove, or if you cannot have surgery because of other health issues.

Chemotherapy

Chemotherapy is the use of anti-cancer medicines that go through your whole body (called systemic). These medicines may be given through a vein (IV, intravenously) or by mouth. More often, non-melanoma skin cancers are treated with topical chemotherapy (goes directly on your skin). Topical chemotherapies do not cause as many side effects as systemic chemotherapy because it does not go through your whole body.

The most common systemic therapy used for basal cell and squamous cell carcinoma is 5-fluorouracil (5-FU). This medication also comes in topical form. Cisplatin can also be used as systemic treatment.

Targeted Therapy

Targeted therapies are medications that target something specific to the cancer cells, stopping them from growing and dividing. Examples of targeted therapies for non-melanoma skin cancer are: vismodegib (Erivedge), sonidegib (Odomzo), cetuximab (Erbitux).

Immunotherapy

Immunotherapy is the use of medications that stimulate (rev up) the immune system to attack and kill cancer cells. Some immunotherapy medications used to treat non-melanoma skin cancer are: Cemiplimab (Libtayo) and pembrolizumab (Keytruda).

Clinical Trials

You may be offered a clinical trial as part of your treatment plan. To find out more about current clinical trials, visit the OncoLink Clinical Trials Matching Service.

Making Treatment Decisions

Your care team will make sure you are included in choosing your treatment plan. This can be overwhelming as you may be given a few options to choose from. It feels like an emergency, but you can take a few weeks to meet with different providers and think about your options and what is best for you. This is a personal decision. Friends and family can help you talk through the options and the pros and cons of each, but they cannot make the decision for you. You need to be comfortable with your decision – this will help you move on to the next steps. If you ever have any questions or concerns, be sure to call your team.

You can learn more about non-melanoma skin cancer at Oncolink.org.