What is lip cancer?

Cancer is described as the uncontrollable division of abnormal cells in parts of the body.¹ This initiation can start almost anywhere. These cells are cancerous and may lead to the formation of abnormal masses of cells called tumours.¹

Lip cancer is a rare type of oral cavity cancer that starts on the lips, with the lower lip being the most commonly affected.^2,3 This can spread to other areas of the mouth and further as the condition worsens.^2,3

Signs and symptoms of lip cancer

This includes:^2,3,4

• A sore on the lip that won’t heal
• Pain, tingling or numbness on the lips and the skin around it
• Raised white discolouration of the lip
• Bleeding
• Crusty area of skin

Risk factors

There is no clear cause as to what causes lip cancer, though there are a few factors that can increase the risk of contracting this condition:^2,3

• Excess/long-term exposure to sunlight
• Tanning beds
• Heavy alcohol consumption
• Diet
• Using tobacco products such as cigarettes
• Being assigned male at birth (AMAB)

There are several types of lip cancer, including:

• Squamous cell carcinoma
• Basal cell carcinoma
• Melanoma
• Minor salivary gland cancer

Squamous cell carcinoma is the most common type of lip cancer, and this is when the squamous cells, which are cells on the surface of the skin and the lining of the digestive tract, including the mouth.⁴

Basal cell carcinoma is the second most common type of lip cancer, which is a type of cancer that occurs in areas exposed to ultraviolet radiation from the sun or tanning beds.⁴

Melanoma is a type of cancer that very rarely forms on the lips. Skin cells called melanocytes, which produce pigment, are where tumours can form, the lips being one of them.⁴

Minor salivary gland cancer is when cancer can arise in the salivary glands in the lips, leading to tumours, though these are rare.⁴

Diagnosis

To determine whether an individual has lip cancer, a few tests can be done, including:^2,5

• A physical exam of the lips, which is done by a doctor, to see if the symptoms an individual is having could potentially be lip cancer^2,5
• A biopsy involves taking cells from the sore on the lip and having them tested by a pathologist to see if it is lip cancer^2,5

Stages

Once cancer has been diagnosed, it is important to confirm what stage the cancer is at, as this determines the extent of cancer in the body, such as how big the tumour is and if it has spread, to what extent.^2,5

There are 5 main stages of cancer:

• Stage 0 – This is when abnormal cells are found in the lips, but they have not yet become cancerous, though they have the potential to⁵
• Stage I – This is when there is a tumour found, but it is very small (less than 2cm), with the spread of the tumour being less than 5mm⁵
• Stage II – This is when the tumour is larger than in stage I or between 2cm and 4cm with a further spread (over 5mm)⁵
• Stage III – If the tumour is larger than 4cm or it has spread to the lymph node^5,6
• Stage IV – There are several stages for stage IV, with IVA being the least severe, where the cancer has spread to the bone, and as the cancer progresses, IVB and IVC^5,6

The stage the cancer is at is what determines the type of treatment needed to treat it.

Surgical treatment for lip cancer

Surgery can be used to treat all stages of lip cancer, and there are 3 main types of surgery that can be used to treat lip cancer:

• Excision surgery
• Mohs micrographic surgery
• Reconstruction surgery

Excision surgery

Standard excision surgery is a type of surgery where the tumour is removed, along with some of the healthy tissue or bone surrounding it, if the cancer has spread there.⁵ The area that is removed from around the cancer is taken and tested by a pathologist, who is a doctor who specialises in looking at tissue cells with a microscope.⁷

A disadvantage to this method is that pathology results can take weeks to determine whether the cancer has been removed or not.⁷  If the cancer has not been removed, then another surgery may be necessary.

It is also important to note that a pathologist’s report is an estimation of how much of the cancer has been, so it is not 100% accurate.⁷

Therefore, this surgery is less commonly used on cancers such as lip cancer, even though it is a good option for other skin cancers.⁷

Mohs’ micrographic surgery

Mohs’ micrographic surgery is when the ‘roots’ of the tumour are found and removed.⁷ This is done in stages, so the tumour is removed first and then a thin layer of healthy tissue around it.⁷ After every layer of tissue is removed, it's examined under a microscope to ensure the tumour is as close to being fully removed.⁷

The greatest advantage of this surgery is that the least amount of healthy tissue is removed around the cancer, while removing as much of the cancer as possible, which helps keep the wound as small as possible for easier healing.⁷

However,  compared to excision surgery, it takes longer and may not always be the most suitable option for certain skin cancers.⁷

Complications and risks

All surgeries contain some level of risk, and for Mohs’ micrographic surgery, the main ones are: pain, swelling, bleeding, bruising, wound infection and nerve damage, which results in weakness or paralysis of the muscle where the damage has occurred.⁷

Reconstructive surgery

When a surgery, such a Mohs’ micrographic or standard excision surgery, is done, there is a wound left that needs to be closed.⁷ There are a few main options for this.

• Healing by secondary intention

Wounds can be left to naturally heal, where you will be shown how to look after the wound by your doctor and how to reapply bandages.⁷ This is what we call healing by secondary intention, which leaves a good cosmetic appearance.

• Primary closure
• The wound can also be pulled closed and stitched, this is called primary closure⁷
• Flap surgery

Tissue around the wound can also be closed by a flap, which is when tissue from loose skin, nearby on the face, is used to close the wound by acting as a ‘flap’.⁷ An example of a flap surgery is ‘Bilateral staircase flap’, which is a technique used for larger tumours on the bottom lip, where skin under the lip is cut like a flap and used to cover the wound, providing an effective way to close the wound in one step.⁸

• Skin/bone graft: The wound can also be covered with a piece of skin from another area of the body, called a skin graft, then left to heal.⁷Bone grafts can also be done when the cancer has spread to the bone and the affected bone has been removed by surgery, so a reconstructive surgery can be done to reconstruct that bone with a bone graft
• Plastic surgery: Depending on how severe the wound is, it can be repaired by a plastic surgeon to help improve the appearance of the wound on the face.⁷ This surgery is often planned before the cancer-removing surgery and is done immediately after the initial surgery or a few days after⁷

Personalised medicine

Personalised medicine is the practice in which treatment is tailored to a specific individual. In the case of lip cancer treatment, it is important to base treatment on individual cases to ensure the best results, both in removing the cancer and in reconstruction and cosmetic point of view.

Therefore, it is important to discuss the best options for you specifically, depending on the severity of the cancer and personal wants and needs.

Summary

Lip cancer is an oral cavity cancer that is characterised by symptoms such as sores on the lips and raised white discolouration on the lips. The chances of cancer can be increased by factors such as tanning beds and heavy alcohol and tobacco consumption. There are 4 types of oral cavity cancer: squamous cell carcinoma, basal cell carcinoma, melanoma and minor salivary gland cancer and 5 different stages of cancer.

To diagnose whether an individual has this cancer or not, there are a few tests that can be done, such as a physical examination or a biopsy. Once the cancer has been diagnosed, there are a few surgeries that can be done to remove the cancer and improve the cosmetic condition: excision surgery, Mohs micrographic surgery and reconstructive surgeries. The surgery used depends on the individual and the severity/type of cancer, which is why it is important to focus on personalised medicine for the best results.