Prevention Strategies And Risk Reduction In Mucosal Melanoma

Brief overview of mucosal melanoma

You have likely heard of melanoma, a form of skin cancer caused by exposure to UV light. In this case, cells called melanocytes in the layers of the skin begin to grow out of control. But what happens when melanocytes in other areas of the body begin to behave like this? If this occurs in cells within the mucosal layers of the body, this is known as mucosal melanoma. This rare and aggressive form of melanoma occurs in the body’s mucous membranes, such as the mouth, nasal passages, and genital areas¹. Signs of this condition include bleeding and pain in these areas.²

Importance of prevention and risk reduction

This form of melanoma is aggressive and has a poor prognosis with an overall 5-year survival rate that is less than 20%. Despite years of research, the progression of the disease remains unclear, and as a result, the risk factors and preventative measures are poorly defined.¹ Unlike cutaneous melanoma (the more common form, occurring in the layers of the skin), mucosal melanoma does not seem to be caused by UV exposure. a direct cause has yet to be identified, which limits therapeutic efforts.² Routine personal examinations are the leading preventative measure, as identifying mucosal melanoma early gives patients the best chance at overcoming this cancer.

Understanding Mucosal Melanoma

Definition and characteristics

Mucosal melanoma is the rarest subtype of melanoma, with around 800 cases per year in the United States, in comparison to cutaneous melanoma which is 100 times more common.³ Like other melanomas, this form appears as an oversized soft lump in the affected area. These lesions can be pigmented, with irregular borders and elevation in some areas.¹ The presence of growth in these mucosal membranes can lead to pain and discomfort. Affected areas may also bleed or produce discharge leading to difficulty swallowing if it is present in the head and neck region.¹

Common sites of occurrence

Mucosal melanoma is most often found in these areas:

• Mouth - including gums and palate
• Throat
• Nasal passage and sinuses
• Windpipe
• Oesophagus
• Anus
• Genitourinary tract - vulva, vagina, urethra³

The majority of cases occur in the head and neck area (55%), with the second most common area being the anorectal region.³

Differences from cutaneous melanoma

Although both cancers arise from out-of-control growth in melanocytes, there are many differences between cutaneous and mucosal melanoma. The mucosal form is often diagnosed at a later stage than its counterpart, likely as a result of the hidden nature of these mucosal areas.¹ Cutaneous melanoma is firmly linked to UV exposure, whereas no link between UV exposure and mucosal melanoma has been established.¹ The incidence of mucosal melanoma is steady in most populations, compared with cutaneous which is steadily increasing. These differences could be due to the genetic origins of these two melanomas: cutaneous melanoma is associated with mutations in the BRAF gene, whereas there are fewer BRAF gene mutations in mucosal melanoma with more occurring in the KIT genes.² 

Risk factors

The lack of understanding of the causes of mucosal melanoma means that it is difficult to identify risk factors for the disease. However, by examining the characteristics of those diagnosed with this cancer, it is possible to identify some populations that may be more at risk.

Genetic Predisposition

Mucosal melanoma appears to be more common in those with a non-European background according to recorded data.⁴ Race can also influence the area where mucosal melanoma is found: incidence of the cancer is highest overall in Caucasians, with Asians more likely to present with anorectal mucosal melanoma, while in Hispanics the cancer is more often found in the head and neck area.² There is no evidence that family history increases the risk of developing mucosal melanoma.⁵ Genetic mutations commonly found in patients with mucosal melanoma occur in the SF3B1, KIT and NF1 genes.⁴

Other Factors 

Age is the clearest contributing factor to mucosal melanoma. The median age of diagnosis is 70, with over 65% of cases occurring in patients over 60.⁶ This cancer also affects women more often than men, which may be due to the higher rates of genitourinary tract melanoma in women.⁶ Mucosal melanoma has also been associated with human papillomavirus (HPV) and herpesvirus, so viral infection may also be a risk factor.²

Prevention stratigies

Prevention and risk reduction are difficult due to the unclear causes and risk factors of mucosal melanoma. Despite this, measures can be taken to ensure early detection and improve prognosis. 

Examination of at-risk areas

Late diagnosis contributes to the poor prognosis of mucosal melanoma, so any steps that can be taken to identify lesions as early as possible will provide a greater chance of overcoming the disease. Regular self-examinations of mucosal areas, such as the mouth, throat and anus, for abnormalities, can provide peace of mind and increase the likelihood of finding the melanoma early. For additional precision, it is possible to ask a healthcare professional to examine these areas during routine appointments.

Awareness of symptoms

In addition to examining the mucosal areas, it is important to be familiar with the symptoms of melanoma. These include:

• Bleeding in mucosal areas
• Nasal obstruction
• Persistent sores in the mouth
• Difficulty swallowing
• Hoarseness
• Unusual vagina discharge
• Rectal bleeding⁷

Recording these symptoms and reporting them to your healthcare provider as soon as possible will allow for prompt treatment and an improved outcome.

HPV vaccination

As previously mentioned, infection with HPV and herpes has been associated with a higher chance of developing mucosal melanoma, especially in the mouth and genital regions. Getting vaccinated against HPV might decrease the overall risk of developing this cancer.⁸ 

Genetic screening

Mucosal melanoma is often associated with mutations in the KIT genes. Genetic screening for mutations in these genes, along with other associated genes such as NRAS and NF1, can provide an incredibly early diagnosis and interventions can begin before lesions have begun to develop.⁹

Support overall health

Alongside more targeted measures, maintaining the general well-being of mucosal areas is a worthwhile preventative measure. Not smoking, cutting down on alcohol and eating well, will promote a healthy mucous membrane. In addition, practising good personal hygiene and safe sexual practices will prevent infections that could lead to mucosal melanoma.¹

Summary

In summary, mucosal melanoma is a rare but aggressive cancer that presents significant challenges due to its late diagnosis and unclear risk factors. Unlike cutaneous melanoma, which occurs in the skin and is linked to UV exposure, mucosal melanoma develops in the mucous membranes of the body and does not have an established direct cause. Despite this, there are strategies to improve early detection and reduce risk. Regular self-examinations and awareness of symptoms are crucial for early identification. Additionally, genetic screening and HPV vaccination can provide proactive measures against the development of mucosal melanoma. Maintaining overall health through a balanced diet, avoiding smoking, and practising good hygiene are also important preventive steps. While research continues to uncover more about this elusive cancer, these strategies offer ways to reduce the risk and aid early detection.