Skin cancer

Definition

Skin cancer is a tumor formed by skin cells that have mutated and multiply in a disorderly and abnormal way, originating a tumor mass (neoplasia). Skin cancers can be divided into non-melanoma skin cancer and melanoma skin cancer. Among non-melanoma cancers, there is basal cell carcinoma, which is the most frequent and less aggressive, and epidermoid (squamous cell) carcinoma, which is more aggressive and grows faster than basal cell carcinoma.

Melanoma is the most dangerous type of skin cancer and one of the most aggressive of all cancers, due to its ability to metastasize. This tumor affects melanocytes, cells capable of producing skin pigment (melanin). There are different types of melanoma, such as nodular melanoma, acral lentigio melanoma, disseminated malignant melanoma, lentigo malignant melanoma, etc.

There are also other rarer types of skin cancer that affect other cells, such as:

– Merkel cell tumor;

– Kaposi’s sarcoma;

– Cutaneous T-cell lymphoma (cancer of the lymphatic system that can attack the skin),

– Sebaceous carcinoma (appears in the sebaceous glands);

– Microcystic adnexal carcinoma (sweat gland tumor).

An Israeli study at the University of Tel Aviv showed that if the melanoma is discovered early, that is, before the formation of metastases, the chances of recovery from the melanoma are very high. On the contrary, if melanoma is found in an advanced stage, when metastases are already present in the body, the disease is usually fatal. This study was published in the journal Nature Cell Biology in August 2016.

Epidemiology

In 2016, it is estimated that 1 person in the world dies every 52 minutes due to the consequences of melanoma (malignant).

In 2016, the number of melanoma cases increased sharply, according to a Tel Aviv University press release in August 2016.

In Switzerland, melanoma affects about 2700 people annually and kills 320, according to an April 2018 ATS article.

Causes

As with other types of cancer, both environmental and genetic factors are linked to skin cancer.

Ultraviolet (UV) radiation from the sun is one of the main causes of skin cancer. This radiation causes DNA damage, reaching genes that control cell growth. This damage is cumulative and, after a certain number of lesions have occurred in the cell’s DNA, the cell cannot repair itself and begins to grow in a disorderly manner, initiating a tumor.

There are 2 types of UV radiation: UVA and UVB. Scientists used to believe that excessive exposure to UVB rays was the main cause of skin cancer, however, recent research shows that UVA rays may also be involved. Other sources of UV rays are tanning booths and ultraviolet lamps. These radiations, in addition to causing damage to DNA, cause sunburn , which causes pain, redness, edema, premature aging and can trigger skin cancer processes.

Genetic factors are also related to the causes of skin cancer. In these cases, the cancer is hereditary and derives from genes received from parents. Presence of dysplastic nevi (skin spots), severe burns and blisters due to sun exposure, and weakened immune system (as in the case of Merkel cell cancer) can also be causes of skin cancer.

Other factors that may also increase your risk of skin cancer:

– Exposure to ionizing radiation, such as radiotherapy;

– Chronic exposure to low amounts of arsenic;

– Genetic syndromes such as xeroderma pigmentosa;

– Chronic skin wounds, such as ulcers and burns;

– Smoking increases the risk of squamous cell carcinoma;

– HPV (human papilloma virus) infection is associated with squamous cell carcinoma of the genital areas and around the nails.

– Genetic factors (family history of skin cancer, etc).

– Taking certain medications. A study of 80,000 Danes, published in 2017, showed that the use of a commonly used hypotensive agent, hydrochlorothiazide, increases the risk of squamous cell carcinoma (in English:  squamous cell carcinoma ) by a factor of seven. The use, if possible, of another hypotensive drug is recommended. This study was published online December 3, 2017 in the scientific journal JAAD (DOI: 10.1016/j.jaad.2017.11.042).

It is important to know that skin cancer can also occur in areas of the skin that are not usually exposed to the sun (UV rays), indicating that factors other than UV rays can cause skin cancer.

Groups of risk

One of the main factors that can trigger skin cancer is exposure of unprotected skin to UV rays. People with very fair skin have less natural protection from the sun’s rays and are therefore more prone to developing skin cancer. People with many moles or freckles are also at increased risk.

Another risk group is people with a family history of skin cancer or with genetic deficiencies, such as xeroderma pigmentosum. People with compromised immunity (or illnesses that lower immunity) are also at increased risk of developing the disease.

In addition, people who live in places with a lot of sunlight (such as in tropical countries) or who are exposed to the sun a lot without adequate protection (rural workers, street vendors, etc.) are at increased risk of developing the disease.

People suffering from Parkinson’s disease. According to a study published in May 2017 by the Mayo Clinic (USA) in the scientific journal Mayo Clinic Proceedings , people with Parkinson’s are about 4 times more likely to develop melanoma. The reverse is also true, which means that a person with melanoma is statistically 4 times more likely to suffer from Parkinson’s. For now, scientists are talking about an association rather than cause and effect. Levodopa (L-Dopa), a drug widely used in Parkinson’s disease, may be at the origin of the increased risk of melanoma, but studies have contradictory results and are not yet conclusive. Genetics can also play a key role.

– People who have suffered multiple sunburns.

– Aircraft crews, such as pilots and flight attendants. Several studies have shown that mariners are at increased risk of developing cancer, including skin cancer, such as a study published in June 2018 in the journal Environmental Health (DOI: 10.1186/s12940-018-0396-8). Throughout their working lives above the clouds, flight attendants and pilots are exposed to a variety of cancer risks – including cosmic and UV radiation, irregular sleep rhythms and possibly chemical use in the cabin.

Symptoms

Skin cancer appears as an abnormal accumulation of cells. It can take the form of a sore that won’t heal, a wart-like lesion, or a non-existent spot that may look dark, red, or shiny. These sores or spots may itch, hurt, or even bleed. Skin cancer can still manifest itself as a growth of an existing spot on the skin.

Basal cell carcinoma is the most common skin cancer. It can manifest itself in the form of a papule (little ball) with a pearly surface (pearly appearance) or a wound that does not heal. The severity of basal cell carcinoma manifests itself depending on the histological type and location of the tumor, being more aggressive in places such as the eyelid, nose, ear and others, where surgery tends to be more difficult.

Squamous cell carcinoma is the second most common type of skin cancer. It may present as a hardened plaque, scaly or crusty, sore area. Watch out for injuries that bleed easily or don’t heal. Squamous cell carcinoma can appear over areas of old burn scarring .

Melanoma is the least common skin cancer, but it is the most dangerous and can cause death. It may appear as a blackened lesion, with ill-defined borders, with colors and diameters that can change over time. People most prone to this type of skin cancer are those with fair skin, who had multiple bouts of sunburn with blisters as children, or people with a family history of melanoma.

It is important to note that not all skin changes are indicative of cancer. Most moles and moles on the skin are benign in nature.

In men, melanoma most often appears on the face or trunk, while in women, melanoma is most commonly seen on the lower legs, as reported by the Mayo Clinic . In both men and women, melanoma can appear on skin that has not been exposed to the sun.

Self-examination helps in the early detection of skin cancer, especially melanoma. When doing the self-examination, look for the following 4 factors (known as the ABCD):

– Asymmetry (one part or half of the pigmented lesion does not correspond to the other half)

– Jagged edges (in addition to jagged edges, they can be serrated or blurred)

– color change, polychromatic (various colors in pigmented lesions)

– Diameter greater than 0.5 cm

– Thickening or extension (including change in color, size or shape)

If any of these symptoms appear, see a doctor.

Diagnosis

Early diagnosis, that is, in the early stages of skin cancer increases your chance of cure. Because skin cancer is visible to the naked eye, the initial diagnostic test is visual inspection. The doctor will observe spots or sores on the skin and if they show symptoms with sores that do not heal, patches of asymmetrical growth and undefined borders, etc. For melanoma, doctors typically use the ABCD signs : asymmetry, undefined (irregular) borders, variable coloration, and increased diameter (diameter greater than 6 mm).

In addition, the doctor may order some additional tests to check the stage of the cancer, such as x-rays, biopsy, blood tests, etc. With the biopsy results, doctors can determine the depth and size of the skin cancer. Clark (levels of skin invasion by the tumor) and Breslow (tumor mass thickness – values ​​in parentheses) classifications are used for melanoma and are divided as follows:

In the case of basal cell carcinoma, the doctor can identify the cancer by physical examination. If squamous cell carcinoma is suspected, the doctor must confirm the disease through a biopsy so as not to confuse it with other diseases. If melanoma-type skin cancer is suspected, the doctor should perform a biopsy.

A recently developed exam that helps in the diagnosis of skin cancer is dermoscopy, in which a device, coupled to a camera, “reads” the patient’s skin and increases the visualization of the points with an magnification of up to 40 times, facilitating identification. skin cancer early.

Complications

Melanoma skin cancer is one of the most dangerous for humans due to its ability to reach other organs (metastasis) and create new tumor masses. Organs affected by melanoma metastasis include lymph nodes, lungs, brain, among others. The risk of metastasis increases as the thickness of the melanoma increases, and early diagnosis and treatment are extremely necessary to avoid tumor irradiation.

In some rare cases, melanoma can spread and reach other sites when it is still small and has not been detected by diagnostic tests . In these cases, the cancer can be mistaken as having its origin in that organ, when, in fact, it is a metastatic melanoma. Because of this, it is important to know the origin of the cancer, as different tumors require different treatments.

Once reached other organs, metastatic cancer can cause several harms to the patient, including death.

As discussed above in the Risk groups section , a 2017 study conducted by the Mayo Clinic (see study references in the Risk groups section ) showed that people affected by melanoma were 4 times more likely to suffer from Parkinson’s disease.

Treatments

Skin cancer treatment will depend on the type of cancer (whether it is melanoma or non-melanoma) and its stage (depth of the cancer).

Treatment of non-melanoma skin cancer

For non-melanoma skin cancer, the initial treatment is surgical removal of the tumor, which can be performed by scraping and burning with an electric needle, electrodissection, or excised with a scalpel. Depending on the extent of the basal cell carcinoma, it can also be treated with topical medications such as tazarotene and imiquimod, and radiotherapy.

In the case of squamous cell carcinoma, the procedure is surgical removal and radiotherapy. Other treatment techniques include curettage and photodynamic therapy, which consists of sensitizing the skin with delta amino levulinic acid (ALA) and applying, in the sensitized region, a laser that kills tumor cells. Photodynamic therapy is indicated for patients who have no indication for surgery, such as people of advanced age and with clotting problems or recurrent tumors, and the therapy is also indicated for patients whose cancer is in areas where the wound has difficulty closing after surgery. surgery, spots that don’t fit well, or places where major surgery with skin grafts or flaps is needed.

The Mohs microsurgery technique is indicated for areas with a high chance of recurrence, such as around the eyes and nose, or for regions that may become deformed after conventional surgery, such as the mouth and lips. It is a special technique that is characterized by removing as little tissue as possible around the tumor. The types of tumors most indicated for this surgery include basal cell carcinomas, squamous cell carcinomas, dermatofibrosarcomas and tumors that affect skin appendages.

Melanoma skin cancer treatment

In the case of melanoma, surgical removal of the tumor mass is the primary treatment. Small tumors can be completely removed, however, only a small part of large tumors can be completely removed. Adjuvant treatments may be given after surgery for cases at high risk of metastasis. In this case, the doctor may treat the patient with chemotherapy agents, radiation therapy or immunotherapy depending on the tumor grade and its stage.

Chemotherapy treatments for melanoma include decarbazine, temozolamide, carmustine, cisplatin, vinca alkaloids (vinblastine), taxanes (paclitaxel and docetaxel), among others. The immunotherapeutic agents used in the treatment of melanoma are monoclonal antibodies that can antagonize the immune response, suppressing it (such as CTLA-4, PD-1) or activated receptors that amplify the patient’s immune response against the tumor (CD137, OX40, CD40 ).

lpilimumab

Treatments such as ipilimumab (Yervoy) are particularly effective against late-stage melanoma. A study published in September 2013 showed that ipilimumab allowed some patients to survive for more than 10 years, according to Professor Stephen Hodi who participated in this study. Ipilimumab is a monoclonal antibody marketed since 2011 in the United States by the BMS laboratory (Bristol Myers Squibbs). Ipilimumab is only effective in 15% of patients and has significant toxicity (source: ATS news agency, Switzerland, 29 September 2013).

Another study showed a 5-year survival rate of 18% among patients taking ipilimumab. Professor Hodi, found in his study through the analysis of available data of 1800 patients treated with ipilimumab, a median survival of 11.4 months, but a much more favorable evolution for about 1 fifth of them: 3 years after starting treatment , 22% were still alive, and after 7 years, they were still 17%. The longest survival was 9.9 years (sources, ATS, 2013).

According to Professor Hodi, the increase in survival was independent of the dose of treatment received or the existence of associated treatments.

Melanoma, when diagnosed early (has not yet produced metastases), has a high chance of being cured. That is why it is always important to carry out a self-examination, evaluating the ABCD symptoms . In case of any suspicion, seek a dermatologist doctor.

Herbal medicine

Drinking 1 to 4 cups of coffee a day would reduce the risk of melanoma, a severe form of skin cancer, by 25%. This meta-analysis (study of studies) was published in November 2015 in the specialized journal  American Journal of Clinical Dermatology  and compared coffee drinkers with those who do not consume this drink. Apparently, several antioxidants found in coffee interfere with the action of the sun’s UV rays at the cellular level, which decreases tumor formation.
Drinking 3 cups of coffee a day was associated with a lower risk of suffering from skin cancer, according to a large study (coverage study or umbrella review in English) published on November 22, 2017 in the British newspaper The BMJ(DOI: 10.1136/bmj.j5024). This study also showed that drinking 3 or 4 cups of coffee a day reduced the risk of overall mortality and heart disease.

Tips

Always do self-examination, checking for signs such as:

– Wounds that do not heal;

– Stains that have increased in size;

– Stains that were non-existent;

-Always check the ABCD symptoms;

– Consult a doctor in any case.

– Be careful with the umbrella: studies show that more than 2/3 of UV rays go through the fabric of umbrellas, reaching our skin and causing a sunburn. Always protect yourself with other means, such as sunscreen and long clothes.

Prevention

– One of the main triggering factors for skin cancer is exposure to the sun. The world’s medical communities recommend avoiding exposure to the sun between 10 am and 4 pm, as the incidence of UV rays is higher during this period.

– Also avoid tanning beds. According to the World Health Organization (WHO) they increase the risk of melanoma skin cancer.

– Always use sunscreen with a Sun Protection Factor (SPF) of at least 15. Reapply sunscreen periodically, even those labeled “waterproof” every 2-3 hours. Consult your dermatologist to check the ideal amount of sunscreen to use, as many people apply less sunscreen than ideal.

– Apply sunscreen about 30 minutes before exposing yourself to the sun.

– If you work outdoors, use extra protection, such as caps (hats), long clothes, sunglasses and always look for shady places.
– Even with sunscreen, avoid direct exposure to the sun during periods of higher incidence of UV rays. These prolonged exposures can cause sunburn that can trigger skin cancer processes.

– Protect yourself from reflective surfaces such as concrete, sand and water that indirectly reach the skin with UV rays.

– Ingest vitamin D. Studies show that taking vitamin D strengthens the immune system and helps prevent skin cancer.

– For more sun and skin tips, read our section on the subject: Sun and Skin

– According to a study released in May 2015, consuming 500mg of nicotinamide (a form of vitamin B3 ) twice a day would reduce the risk of skin cancer recurrence by 23%. These benefits do not apply to the most serious form of skin cancer, melanoma, but to less aggressive forms of the disease, such as basal cell skin cancer. This study was conducted by Prof. Diona Damian of the University of Sydney in Australia.

Sources & References:
JAAD (DOI: 10.1016/j.jaad.2017.11.042), Mayo Clinic Proceedings, Environmental Health (DOI: 10.1186/s12940-018-0396-8)

Jeanne Kenney
Website | + posts

I’m a stylist trainer, a content creator, and an entrepreneur passion. Virgo sign and Pisces ascendant, I move easily between my dreams, the crazy world I want, and my feet on the ground to carry out my projects.

Leave a Reply

Your email address will not be published. Required fields are marked *