Is mucosal melanoma related to light exposure? Will malignant melanoma metastasize to distant sites?

Melanoma is a highly malignant tumor with an incidence rate of about 44/100,000 in the population. Among them, the incidence of mucosal melanoma is relatively low, accounting for about 4-5%. However, malignant melanoma of the head and neck accounts for more than half of the total mucosal melanoma. In addition, there is a high rate of metastasis and disease progression, and the prognosis is extremely poor.

1. Is mucosal melanoma related to light exposure?

Skin melanoma can be divided into chronic sun damage type and non-chronic sun damage type. In daily life, the malignant condition caused by sun exposure that people are worried about is the sun damage type.

Generally speaking, if the melanocytes in the skin absorb excessive ultraviolet radiation for a long time, coupled with genetic changes in the skin, it may cause mutations in the melanocytes, leading to malignant changes, that is, melanoma.

Melanoma in my country is mainly of acral type and mucosal type. Mucosal type accounts for 50% of all melanomas. It often appears in the head and neck mucosa, nasal mucosa, including sinuses, nasal cavity, oral cavity and other places that are not directly exposed to sunlight, so mucosal melanoma has no direct connection with light.

That is to say, not all melanomas must live in the dark, and there is no correlation between melanomas that occur in the mucosa and light exposure. Patients should distinguish them according to their own lesions and do not need to be afraid of "light".

2. Distant metastasis of malignant melanoma

Malignant melanoma often occurs in people around 60 years old, and the three-year survival rate does not exceed 50%. The main reasons for this poor outcome are the high distant metastasis and lymphatic metastasis of malignant melanoma. Generally speaking, tumors spread to other parts of the body through blood metastasis and lymphatic metastasis. It is equivalent to taking these two conveyor belts to go to other farther parts of the body.

For malignant melanoma of the skin, tumor cells are more often transported through lymphatic vessels, resulting in lymph node metastasis and metastasis to distant corresponding parts. The specific metastasis mechanism of malignant melanoma of the mucosa is still unclear, but metastasis to parts far away from the patient's initial lesion is still common. Therefore, regular and comprehensive screening and judgment are required for mucosal malignant melanoma. The lymph node metastasis rate of oral malignant melanoma is higher than that of other head and neck malignancies. Therefore, patients with oral malignant melanoma should pay special attention to whether there are any abnormalities in their own lymph nodes.

The symptoms of advanced melanoma vary according to the different metastatic sites. The most common sites of metastasis are the lungs, liver, bones, and brain. Given the frequent occurrence of distant metastasis in malignant melanoma, we still need to pay attention to regular review and evaluation to avoid delaying treatment.