Difference Between Melanoma and Carcinoma

When it comes to the layer that covers all our bodies, maybe most of us don’t pay much attention to it comparing to other body organs, and yes, the whole skin is considered a single organ since it is made of 19 million cells working together to be the first barrier of defense in many ways (1).

And like any groups of cells it is vulnerable to mutations that cause an abnormal group of cells to form a tumor and if there is a significate mutation (malignity) it is considered a cancer. Now, we need to separate the concepts of tumor and cancer with the size of it, since we can be in the presence of a big tumor or a small cancer, it all depends in the level of difference we have with the abnormal mutated cell and a normal one.

Now talking about skin cancer there are 2 major groups: melanomas and non-melanomas (all types of carcinomas on the skin). Both are malign tumors or cancers, terms that have an ambiguous difference outside the pathology laboratory.

The melanoma is a mutation that starts on the melanocytes, these are the cells that have the pigment (melanin) that defines the different color tones of our skins, so race war is basically a war against a microscopic pigment.

The first difference would be the type of cell they attack first, in the other hand there are 2 major types of carcinomas, which along with the melanomas makes the 99% of skin cancers (3):

Basal cell carcinoma is the most common of the carcinomas with 70 to 80% prevalence, it is formed in the mother cells of the skin, that has a higher possibility of mutation because from these cells all the other cells in the skins are born.

Squamous cell carcinoma: It completes the other 20% of carcinomas, and it develops from the squamous cell, basic plane cells that are present in most of the organism, conforming the inner skin of a lot of organs. It is the rarest but also the carcinoma with the highest percentage of mortality.

The role of UV lights

With the increasing damage to the ozone layer of the atmosphere due to global warming, the UV rays trespass to earth way easier. UV light in the human body, with its high radiation, breaks DNA in skin cells provoking mutations of important genes that suppresses the birth of cancer cells, which may trigger the onset of a tumor. Along with family genetic predisposition, it increases the chances of having a carcinoma or melanoma (3).

All types of skin cancer are now considered to be in some way induced by exposure to UV lights, but depending on the type of skin, that goes from 1 to 6 in dermatological terms, the number 1 would be the lighter skin that is more vulnerable to UV ray damage and burns, and 6 would be less vulnerable to these factors.

Nevertheless, dark skin humans, due to this resilience to sunlight, need an extra exposure to sun (3 to 6 more times according to The Cancer Council of Australia) because of vitamin D; this vitamin needs the action of daylight to be synthetized or created in the skin.

Recognizing the early symptoms

The most important thing about your health is to listen to it constantly, if recognized early, the survival rates are very high for non-melanoma skin cancer (Basal cell and squamous cell carcinoma) in the other hand as a second difference, there is evidence that the survival rates for melanoma decreases as we get older from 90-95% for 15-39 years old, to 80% for men and 85% in women of 70-79 years (4).

The survival rate also decreases depending on the stage where we spot the cancer, getting to a 50% for stage 4 melanoma diagnosis, that is why it is utterly important to know the early symptoms:

Melanoma:

In an early stage melanoma can look like a freckle, but you must be in the lookout for quick changes in color, shape or size. Nodular melanoma is an aggressive form that quickly raise in a dome and it often bleeds. Fortunately, melanoma is the most uncommon type of skin cancers.

There is an ABCD medical guideline mostly used for Melanomas:

A= Asimetry. A regular form means it has defined shape and geometric patterns (i.e regular moles), the opposite happens in malign lesions such as the melanoma.

B= Border. Malign lesions have unlimited borders, with irregular edges

C=Colour. Not only the increase in color intensy, but also the different colors (red, black, blue) that may appear in the same lesion.

D=Diameter. It refers to the expansion in any direction, up or sideways of the malign lesion

Non-Melanomas:

Basal cell carcinoma (BCC): As a third difference, we have a less colorful pattern in the carcinomas, BCC also grows slower and it appears dry and peeling.

Squamous cell carcinoma: the less frequent type of carcinoma might ulcerate (form a hole) easier, bleeding may occur and it may look like a wrinkled parchment paper. The color remains pale or barely red.

For a look of early stage skin cancer photos, you can visit:  The Cancer Council of Australia

For a Definitive diagnosis, ultimately, we need a biopsy of the suspicious skin lesion, to observe them under the microscope and identify the mutation and the degree of malignity. That way we can stage the cancer and define the adequate treatment and prognosis.

The evolution of skin cancer treatment

The survival rates on skin cancer rates has increased significantly over the years with the evolution of health sciences, like on all types of cancers. Survival rates after one year of malignant melanomas has increased from 75% in 1971-72’s England and Wales, to a great 97% in 2010-11 in men. For women, the rates have gone up from 87% to 98% in the same study.

And of course, they evaluated the 10-year net survival: For men, it increased from 35% to 86% and for women from 55% to 92%. In general, 90% of the people with diagnosed melanomas in the UK in that time frame, survived the complications and consequences of cancer after 10 years. (4)

The survival rates for non-melanoma cancers (Basal cell carcinoma and squamous cell carcinoma) have always been very high and with the current education on health issues, especially for industrialized countries, you can almost always cure a skin carcinoma. (5)

The treatment for carcinomas consists in the removal of the tumor in addition with radiation therapy in some occasions.

As for melanomas, early stages can be treated with removal alone, but more advanced cancers may need a combination of chemo and radiotherapy. There are novel approaches like cryotherapy, immunotherapy, target therapy that attacks proteins of the tumor, that needs further investigation to be implemented widely.

According to the stage, also considering current diseases, age or immune susceptibility, the treatment can be defined for melanomas:

• Stage 1: Surgery for removal is often the solution, a biopsy determines the grade of malignity and if necessary, a biopsy of the sentinel lymph node (the closest to the tumor).
• Stage 2: Surgery and the biopsy of the sentinel node is almost always recommended together, with a time frame between them, since this is a more malign tumor. Some safe clinical trials might be recommended, to prevent the tumors comeback.
• Stage 3: Surgery+ sentinel node+ radiation therapy (especially if the cancer spreads to the closet lymph node). Direct chemotherapy to the node might be considered as well.
• Stage 4: In this case, we would need to use all the weapons: surgery for metastasis (when cancer spreads) in other organs might be necessary. Some immunotherapies have proved mild results, and systemic chemotherapy might be considered. Recurrent melanomas need the same or extra treatment, with new cycles of chemotherapy.

Visit the American Cancer Society for more helpful information.

Alright, that was it! let’ss review some major differences between carcinomas and melanomas: