[Kim Jaeho's Life Story]<262> Misconceptions and Truths About Skin Cancer

Among the numerous diseases that affect the skin, skin cancer is not very common, accounting for less than 1% of skin disease cases. However, many people suffer severely or die from skin cancer, so it causes significant concern when diagnosed.

The skin contains three types of cells just below the surface: squamous cells located just beneath the skin surface, basal cells beneath the squamous cells that produce new skin cells, and melanocytes located in the lower epidermis that produce melanin pigment responsible for skin color. Skin cancer is classified into squamous cell carcinoma, basal cell carcinoma, and melanoma depending on which of these three cell types becomes cancerous.

Globally, among the three types of skin cancer, squamous cell carcinoma and basal cell carcinoma, which are relatively easy to treat and have a good prognosis, have not attracted much attention. However, melanoma, which has a relatively poor prognosis, has garnered significant interest, and related statistics are readily available. According to the World Cancer Research Fund (WCRF), melanoma had about 330,000 new cases in 2022, ranking it as the 17th most common cancer by type.

In South Korea, the 5-year relative survival rate for melanoma varies by specialized institution, but generally, it is over 95% if the cancer has not metastasized to other tissues or organs, 60-70% if it has spread to nearby tissues or lymph nodes, and about 15-30% if it has metastasized to distant organs. This indicates that the 5-year relative survival rate for melanoma that has spread to other tissues or organs is not very favorable.

Additionally, the number of deaths from skin cancer has remained around 500 annually since 2015 and has stayed at about 550 since 2020. Considering that deaths from squamous cell carcinoma and basal cell carcinoma are not many, it is reported that most of these deaths are due to melanoma. Compared to the recent annual new melanoma cases of 600-700, melanoma is a considerably fatal cancer unlike squamous cell carcinoma and basal cell carcinoma.

The basic treatment for skin cancer, including melanoma, is surgical excision of the cancerous tissue. Other treatments include radiation therapy, chemotherapy, targeted therapy, immunotherapy, Mohs micrographic surgery, cryotherapy, and photodynamic therapy. However, treatment outcomes for melanoma are much poorer compared to squamous cell carcinoma and basal cell carcinoma.

Melanoma diagnosed early and treated appropriately does not have a very poor outcome. However, melanoma that has metastasized to other organs often has a poor prognosis, so prevention is a good strategy.

To prevent and cure melanoma, it is necessary to understand its exact causes. Excessive ultraviolet (UV) exposure is the most frequently cited cause of melanoma and other skin cancers. Other risk factors include environmental factors such as radiation and toxic substances including arsenic, use of immunosuppressants, viral infections, and genetic factors.

Among these various risk factors, to reduce UV exposure, we often see people covering their faces completely except for their eyes. While such efforts may contribute somewhat to melanoma prevention, it is important to remember that excessive avoidance of UV rays can cause serious problems due to UV deficiency, potentially causing more harm than good.

The biggest problem caused by UV deficiency is insufficient production of vitamin D, which plays an important role in the body. This can lead to problems maintaining the health of bones, teeth, and muscles. Children may develop bone deformities such as rickets, and adults may experience bone pain due to osteomalacia.

Vitamin D is produced well when exposed to UV rays, so health organizations generally recommend exposing oneself to sunlight for 5-15 minutes 2-3 times a week to avoid vitamin D deficiency. According to data from the Korea Disease Control and Prevention Agency, surprisingly, 87% of Korean men and 93% of Korean women are deficient in vitamin D. This suggests that for health, UV exposure should not be reduced but rather increased.

Vitamin D deficiency is not the only problem caused by insufficient UV exposure. Humans are fundamentally created to live while receiving sunlight. When exposed to sunlight, brain cells produce endorphins, which are happiness-inducing substances that improve mood and provide mental stability. Sunlight exposure also triggers various beneficial processes including vitamin D synthesis. Excessive avoidance of sunlight prevents these positive effects.

UV rays, including artificial UV, are also used to treat various skin diseases such as rickets, psoriasis, vitiligo, atopic dermatitis, and localized scleroderma. According to a study on the positive effects of UV rays, UV exposure induces the production of nitric oxide (NO) in the body, which lowers blood pressure, improves cardiovascular health, has antimicrobial effects, and can act as a neurotransmitter.

However, excessive UV exposure increases the risk of various diseases including skin cancer, so it is necessary to limit excessive exposure. Health organizations recommend direct sun exposure for 10-30 minutes several times a week,

while advising to avoid outdoor activities during peak UV hours from 10 a.m. to 4 p.m. as recommended by the World Health Organization (WHO). When going outdoors during these hours, it is advisable to wear wide-brimmed hats, protective clothing, or use appropriate sunscreen to protect the head, face, and neck from UV rays.

To prevent and cure skin cancer including melanoma, it is necessary to eliminate the causes of skin cancer. This involves correcting harmful lifestyle habits that cause significant DNA damage to skin and immune cells and interfere with DNA repair. This means avoiding carcinogens and reducing cancer-promoting behaviors that hinder the body's top "doctor," while increasing life-supporting behaviors that create a good environment for the body's top "doctor" to work enthusiastically. This lifestyle is called Newstart (refer to Life Story Part 6).

Among the eight components of Newstart, the first is life diet, which involves eating a variety of plant-based foods including fruits, vegetables, and grains in their whole form without selective eating. Along with this, it is important to reduce intake of sugar, processed or refined bad carbohydrates, saturated and trans fats, salt, and alcohol, which cause many problems when consumed excessively. Practicing the other Newstart components?exercise, water, sunlight, temperance, air, rest, trust, and love?is also crucial.

Independent Researcher