Humans have been living on Earth since at least four million years ago, and the sun has been shining for about four point six billion years and it’s been shining towards Earth for most of that time. But strangely enough no animal has ever contracted skin cancer because of being in the sun all day except humans, who by the way rarely did until about some fifty years ago. The significant increase in skin cancer cases realted to sun exposure may be due to global warming and the hole that has been made in the ozone layer that protects. The ozone layer is thinning rapidly, more in some areas than others, but mostly in the South Pole during the fall and winter seasons and there is some minor but important thinning in the northern hemisphere. The ozone layer that protects planet earth, wich is about ten kilometers high, acts as a shield in preventing dangerous radiations from the sun and from outer space to reach the biosphere we live in, however and interesting fact is that the coincidence on forms of skin cancer are higher in people who live in and around the tropics where there is virtually no thinning of the ozone layer, so the mistery prevails.

An interesting fact to note is that the industrial chemical sunscreen we commonly know was introduced in the late nineteen twenties and by the mid thirties the first commercially available sunscreen product was being sold by the L’Oreal brand.Monsanto also began to produce artificial chemicals for use in blocking UVA and UVB rays from the sun.

In the world we live in there are an estimated two hundred and fifty different species of bacteria which reside on the human skin. Sebum secreted by the sebaceous glands in our skin is an oily substance that is composed of free fatty acids, wax monoesters, triglycerides and squalene wich are there for a reason.

The bacteria mentioned before and the oily substances we secrete actually help protect the skin but we seem to have come up with endless ways to destroy this natural protective barrier. Chemicals not only strip the skin of its natural protection, they are absorbed through the skin and into the bloodstream where they continue to cause damage.

We have a tendency to destroy this protective barrier. We slather our skin with many toxics most of which gets absorbed into our bloodstream. There are over one hundred and fifty cancer causing chemicals currently used in the cosmetics industry, and although federal law requires products containing these ingredients to carry a warning label no one enforces this law.

Sunscreen ingredients absorb into the blood, and most are linked to toxic effects. Some release skin damaging free radicals, some disrupt hormone systems and several are strongly linked to allergic reactions. Be careful what products you use and always read the labes to be sure you are getting the best there is.

UV radiation is part of the electromagnetic light spectrum that reaches the earth from the sun. It has wavelengths shorter than visible light, making it invisible to the naked eye. These wavelengths are classified as UVA, UVB, or UVC, with UVA the longest of the three at 320-400 nanometers. UVA is further divided into two wave ranges, UVA I, which measures 340-400 nanometers and UVA II which extends from 320-400 nanometers. UVB ranges from 290 to 320 nm. With even shorter rays, most UVC is absorbed by the ozone layer and does not reach the earth, both UVA and UVB, however, penetrate the atmosphere and play an important role in conditions such as premature skin aging, eye damage, and skin cancers. They also suppress the immune system, reducing your ability to fight off these and other maladies.

By damaging the skin’s cellular DNA, excessive UV radiation produces genetic mutations that can lead to skin cancer. Both the U.S. Department of Health and Human Services and the World Health Organization have identified UV as a proven human carcinogen. UV radiation is considered the main cause of nonmelanoma skin cancer, including basal cell carcinoma and squamous cell carcinoma . These cancers strike more than a million and more than 250,000 Americans, respectively, each year. Many experts believe that, especially for fair-skinned people, UV radiation also frequently plays a key role in melanoma, the deadliest form of skin cancer, which kills more than 8,000 Americans each year.
UVA. Most of us are exposed to large amounts of UVA throughout our lifetime. UVA rays account for up to 95 percent of the UV radiation reaching the Earth’s surface. Although they are less intense than UVB, UVA rays are 30 to 50 times more prevalent. They are present with relatively equal intensity during all daylight hours throughout the year, and can penetrate clouds and glass.

UVA, which penetrates the skin more deeply than UVB, has long been known to play a major part in skin aging and wrinkling (photoaging), but until recently scientists believed it did not cause significant damage in areas of the epidermis where most skin cancers occur. UVA contributes to and may even initiate the development of skin cancers. UVA is the dominant tanning ray, and we now know that tanning, whether outdoors or in a salon, causes cumulative damage over time.

UVB, the chief cause of skin reddening and sunburn, tends to damage the skin’s more superficial epidermal layers. It plays a key role in the development of skin cancer and a contributory role in tanning and photoaging. Its intensity varies by season, location, and time of day. The most significant amount of UVB hits the U.S. between 10 AM and 4 PM from April to October. However, UVB rays can burn and damage your skin year-round, especially at high altitudes and on reflective surfaces such as snow or ice, which bounce back up to 80 percent of the rays so that they hit the skin twice. UVB rays do not significantly penetrate glass.

Modern sunscreen products provide broad spectrum UV protection and may contain one or several UV filters. A modern UV filter should be heat and water resistant, non-toxic and easy to formulate. Identification of a substance that meets these criteria is as difficult as discovering a new drug; hundreds of new molecules are synthesised and screened before a lead candidate is identified. The most important aspect in the development of a new UV filter is its safety.

In laboratories, the safety of new ultraviolet filters is assessed by an initial extensive testing on its properties as a sun screen including photostability, cytotoxicity, photo-cytotoxicity, genotoxicity and photo-genotoxicity tests. These tests are performed in mammals, yeast and bacterial cell systems and skin penetration potential is measured in vitro using human skin, or, when required by regulations, in vivo.

Because modern sunscreens are selected on the basis of their retention on and in the stratum corneum and are formulated as poorly penetrating emulsions, they generally have very low to negligible penetration rates. The safety and efficacy of UV filters are regulated and approved by national and international health authorities while Safety standards in the US, Europe or Japan stipulate that new filters pass a stringent toxicological safety evaluation prior to approval. The safety dossier of a new UV filter resembles that of a new drugs include acute toxicity, irritation, sensitisation, phototoxicity, photo-sensitisation, subchronic and chronic toxicity, reproductive toxicity, genotoxicity, photo-genotoxicity, carcinogenicity and, in the US, photocarcinogenicity testing.

The margin of safety of new UV filters for application to humans is estimated by comparing the potential human systemic exposure with the no-effect level from in vivo toxicity studies. Only substances with a safe toxicological profile and a margin of safety of at least 100-fold are approved for human use. Finally, prior to marketing, new UV filters undergo stringent human testing to confirm their efficacy as well as the absence of irritation, sensitisation, photo-irritation and -sensitisation potential in man. UV filters not only protect against acute skin injury, such as sunburn, but also against long-term and chronic skin damage, including cellular DNA damage, photo-induced immune suppression and, by extension, skin cancer. The protection provided by modern sunscreens against UV-induced skin cancer was shown in animal photocarcinogenicity studies and confirmed by numerous in vitro, animal and human investigations: UV filters protect the p53 tumour suppressor gene from damage and prevent UV-induced immune suppression. Recent studies suggest that sunscreens protect against precursor lesions of skin cancer, such as actinic keratoses.

Additional benefits of ultraviolet filters include prevention of photo-dermatoses, such as polymorphic light eruption, and, possibly, photo-ageing. Modern sunscreens are safe for children and adults. Percutaneous penetration and irritation rates of topically applied substances in children and adults are similar. The principal protective measure is to keep children out of the sun and/or to cover them with protective clothes; however, sunscreens are often the only feasible defence of children against UV radiation. In conclusion, sunscreens are safe protective devices against a carcinogenic hazard that undergo stringent safety and efficacy evaluation.

A skin graft is a piece of healthy skin that replaces diseased tissue. It is a procedure most commonly used over a badly injured area, or places with skin ulceration, severe burns, and chronic infections. The healthy skin is usually taken from a different location on the afflicted person, but can come from a number of places. There are five types of skin grafts. The most common type is an autograft, when the healthy skin is taken from a donor site on the injured person’s own body. Donor areas are generally a large site where skin is plentiful and circulation will be strong to help with healing, such as the leg.

Other types of grafts are less common, but still valid. An allograft is a skin graft taken from another human donor. A xenograft is a non-permanent skin graft made up of non-human tissue, usually from pigs, that temporarily seals a wound while healing but will eventually be rejected by the body. An isogeneic skin graft is when the donor is genetically identical to the recipient, such as with identical twins. The last kind of skin graft is prosthetic, which is the use of non-tissue or synthetic material, like plastic, to seal the wound.

A skin graft can be classified as partial or full thickness. A partial skin graft is most common and involves shaving a layer of skin from the donor site. A full thickness graft is taken by digging several layers in the epidermis of the donor site to take a thick chunk of the skin. This thicker sample leaves a less visible scar in the recipient area, but a significant gap in the donor area that must be attended to.

The procedure usually begins with general anesthesia. The donor area is cleaned and a tool called a dermatome shaves away a layer of skin from the site. Sometimes surgeons choose to slice the skin into a basket weave pattern, a step that some believe helps in the healing process. The recipient area is also cleaned and the donor skin is placed over the wound. Sutures hold the new skin in place, while pressure is placed on the area with gauze, netting or casting to help the skin adhere.

Following the procedure, the donor area is usually quite sore. Both sites are monitored for infection and bleeding. The recipient site will be checked regularly to ensure that the new skin is being accepted. If the procedure is successful, full recovery takes about three or four weeks.

Sometimes skin cancer patients find that the virus is very resilient, and will either keep returning when you thought the treatment is over or resist treatment all together. When this scenario occurs, a good alternative is to use x-ray radiation to eliminate the cancer calls. This a very efficient treatment that requires multiple visits over a period of time, but the results are very promising. The X-ray treatment should be repeated until the present cancer cells are completely and totally destroyed. This Radiation is not a preferred treatment for skin cancer however it has been observer that in some cases no other treatment will be effective, so further studies into this alternative skin cancer treatment are in study.

There are many instances for which a specific patient’s condition or disease combined with a myriad other factors will require radiation treatment to be used to try to fight skin cancers. There are also many other reasons why an affected patient with skin cancer may seek out x-ray radiation treatment over other types of remedies. One possibility is that the patient has inherent medical or health risks that would prevent them from other types of treatment. Another reason might be if the complete area where the skin cancer is found is either too large or in an part of the body that is not conducive to treatment with surgery, and there are other reasons why radiation treatment with x-rays might be sought. It is always possible that a skin cancer has been treated but is reoccurring frequently. Skin cancer isn’t a sure or easy thing. This type of treatment in particular does show some success - a twenty five to fifty percent drop in re-ocurrence of the disease.

Radiation treatment of skin cancer carries significant risks. The radiation may lead to new cancers in the area surrounding your current cancer. Such cancers will be much more difficult to treat because of the radiation exposure. Healthy skin in that area may also be seriously damaged.

There are also other considerable side effects to have in mind when you are thinking about skin cancer radiation treatment. You may also experience fatigue, nausea, hair loss and redness in the area as another side effect of this kind of radiation therapy. Generally this side effects will disappear when the treatment is stopped, but still patients have to endure the grulling remedy.

If you are considering this kind of skin cancer treatment, your doctor should have already discussed the potential costs and side effects that it may cause. You need to be sure that this treatment is worth the risks that you are assuming. Radiation treatment may not be your best option for fighting skin cancer, and your doctor should be asked if any other means of treatment will be effective.

Squamous cell carcinoma is a common form of lung cancer, accounting for approximately one-third of all cases of bronchogenic carcinomas. Unlike adenocarcinoma, it is strongly linked with a history of cigarette smoking. Its histogenesis may be related to chronic inflammation and injury of the bronchial epithelium, which leads to replacement of the normal ciliated columnar epithelium by a squamous epithelium. This transformation from a glandular epithelium to squamous epithelium is known as squamous metaplasia.

Histolory studies have revealed a series of changes that occur over many years and represent a morphologic progression to bronchogenic carcinoma. Early changes include a loss of the ciliated columnar epithelium, basal cell hyperplasia, and the formation of a low columnar epithelium without cilia. These changes are followed by a squamous metaplasia. As cellular atypia develops and advances there is progression through mild, moderate and severe dysplasia to carcinoma in situ. Carcinoma in situ has no metastatic potential. However, once carcinoma in situ penetrates the basement membrane to involve the lamina propria, it is invasive carcinoma and capable of widespread dissemination. These progressive changes are similar to those that proceed the development of squamous cell carcinoma in the uterine cervix. This progressive sequence would suggest that it would be possible to detect abnormalities that are linked to bronchogenic carcinoma.

Most squamous cell carcinomas arise centrally from either the main, lobar or segmental bronchi and ulcerate through the mucosa into the surrounding lung parenchyma. Their central location also tends to produces symptoms at an earlier stage than tumors located peripherally. Although symptoms tend not to be specific, most commonly a non-productive cough, they stem from the involvement of vital structures at the hilar area of the lung. Most patients, however, are detected by a routine chest radiograph, before they are symptomatic. Larger tumors are associated with chest pain, loss of appetite, loss of weight and dyspnea on exertion.

Despite the fact that squamous cell carcinomas are rare, they can cause a characteristic radiographical and clinical syndrome. They are the most common cause of the Pancoast or superior sulcus syndrome. Endobronchial squamous cell carcinoma commonly leads to bronchial obstruction and post obstructive pneumonia. The common radiologic manifestations of squamous cell carcinomas result from the partial or total bronchial obstructions which leads to pneumonia or atelectasis. One characteristic radiographic sign is the “S sign of Golden” which is due to the inability of the upper lobe to completely collapse. The tumor causes the bulging of the minor fissure on the right leading to a sigmoid shape.

What is the Definition of Basal Cell Cancer or Carcinoma?

Basal cell carcinoma is a type of skin cancer. It is a malignant epithelial cell tumor that begins as a papule (a small, circumscribed, solid elevation of the skin) and enlarges peripherally, developing into a crater that erodes, crusts and bleeds. Metastasis is rare, but local invasion destroys underlying and adjacent tissue. In 90 percent of all cases, the lesion is seen between the hairline and the upper lip.

Description of Basal Cell Carcinoma

Basal cell carcinoma (BCC) is the most common and least lethal form of all cancers. In the United States, basal cell cancer accounts for 90 percent of all skin cancers in the southern states, and 47 percent in the northern states. It occurs most frequently in people over 45 years of age, and almost twice as often in men as in women. The incidence is far more prevalent among Caucasians. It occurs less often in Asians and rarely among African-Americans. The risk of skin cancer is related to the amount of sun exposure and pigmentation in the skin. The longer the exposure to the sun and the lighter the skin, the greater the risk of skin cancer.

Causes of Basal Cell Carcinoma

The main cause of basal cell carcinoma of the skin is ultraviolet radiation from the sun. The earth’s ozone layer offers protection from UV radiation by blocking it. However, depletion of the ozone layer since the late 1970s has increased the damage to the skin that can result in cancer. Clinical trials are determining if this skin cancer can be prevented.

Symptoms of Basal Cell Carcinoma

The five most typical characteristics of basal cell carcinoma are quite different from each other. Frequently, two or more features are present in one tumor. In addition, basal cell carcinoma sometimes resembles non-cancerous skin conditions, such as psoriasis or eczema. Only a trained physician, usually a dermatologist, can diagnose this cancer.

It is advisable to learn the signs of basal cell carcinoma and examine the body regularly, as often as once a month, if at high risk. A full-length mirror and a hand-held mirror can be very useful for the less visible parts of the body. The five warning signs of basal cell carcinoma are:

* An open sore that bleeds, oozes or crusts, and remains open for three or more weeks. A persistent, non-healing sore is a very common early manifestation.

* A reddish patch or an irritated area, frequently occurring on the chest, shoulders, arms or legs.

* A smooth growth with an elevated, rolled border and an indentation in the center. As the growth slowly enlarges, tiny blood vessels may develop on the surface.

* A shiny bump that is pearly or translucent and is often pink, red, white and can also be tan, black or brown, especially in dark-haired people.

* Scar-like area which often has poorly defined borders. The skin appears shiny or taut when diagnosing basal cell cancer.

Melanoma, which often begins in the form of a mole, is the most deadly type of skin cancer. Patients with metastatic (Stage IV) melanoma have cancer that has spread from its site of origin to distant sites in the body. These patients cannot be cured with surgery alone and appear to benefit modestly from currently approved systemic therapies. Although there are many choices of therapy for patients with metastatic melanoma, cancer still progresses in the majority of cases. Clinical response after treatment is, however, observed in 5-10% of patients with metastatic melanoma. These responses, some of which are long lasting, have generated optimism about treatment of this disease. Researchers continue to explore new approaches to the treatment of melanoma, including new targeted therapy and new combinations of drugs.

VEGF is a protein that stimulates cancer to grow. Unfortunately, when melanoma cells are exposed to chemotherapy, VEGF goes into overproduction, which may result in chemotherapy resistance. Avastin is a targeted anticancer drug that slows or prevents the growth of new blood vessels by inhibiting VEGF; this deprives the cancer of oxygen and nutrients. Through its effects on blood vessels, Avastin may also improve the delivery of chemotherapy to cancer. Researchers have speculated that the addition of Avastin to chemotherapy may help control tumor growth and progression more effectively than chemotherapy alone.

Researchers with the North Central Cancer Treatment Group Study NO47A conducted a Phase II clinical trial in 53 patients with inoperable metastatic melanoma who had not received prior therapy. All patients received treatment with Paraplatin, Taxol, and Avastin. The partial response rate was 17%, and 57% of patients had stable disease for at least eight weeks. Median progression-free survival was six months, and median overall survival was 12 months. The most common severe toxicities were low blood cell counts, high blood pressure, and anemia. One patient died after eight cycles of treatment; however, the cause of death was associated with hemorrhaging in a previously undiagnosed brain metastasis.

The researchers concluded that this drug combination was “moderately well tolerated and clinically beneficial in patients with metastatic melanoma.” Research will likely be ongoing to evaluate the benefits of adding Avastin to chemotherapy in this patient population when treating melanoma.