The skin, like the other organs of the human body, can be the seat of benign and malignant growths and ulcers. The malignant ones are, in the majority, cancers or, nevertheless, tumors practically equivalent to cancer, so that they can be dealt with, without doing violence to them, within the framework of the cancer problem. Even in the case of skin cancer, the cause is known only in a few cases, while in many it remains unknown to this day.
Incidence of skin cancer
Malignant melanoma or black skin cancer is a highly malignant tumor of pigment cells (melanocytes). The cancer not only destroys the terrain on which it grows, but over time it metastasizes via the associated lymphatic channels and lymph nodes, which continue to spread to other parts of the body and organs via the bloodstream, eventually leading to the death of the affected person unless the rampant growth is radically countered in time. At first sight, skin cancer does not differ fundamentally in its behavior from cancer of other organs; on closer examination, however, we can recognize some peculiarities that are well worth mentioning and, moreover, are so concise that they can be made plausible to anyone relatively easily. The skin, as the largest and weightiest organ of the body, is at the same time its outer covering; its normal and pathological signs are directly accessible to the searching eye and the palpating finger. This fact helps to detect all its changes earlier and faster than elsewhere. Microscopic examination of the tissue structure also reveals skin cancer to be extraordinarily multiform, much more multiform than the surface changes visible to the naked eye would at first suggest. However, it is the same here as elsewhere, namely that the rarities have considerably less practical significance than the average findings. Almost exactly 98 percent of all malignant skin tumors are distributed among three easily distinguishable clinical pictures whose typical characteristics are relatively easily recognizable: the basal cell carcinoma, the skin carcinoma and the malignant melanoma. The occasionally occurring special forms need not be mentioned here; however, it must be pointed out that in advanced cancer diseases of other organs the metastases originating there can also settle in or on the skin from case to case. The form and behavior of such skin metastases bear the characteristics of the respective primary tumors.
Skin carcinoma
Schematic diagram showing the anatomy and structure of the skin with black skin cancer. Click to enlarge. Skin carcinoma, cancer in the strict sense, increases markedly in size within weeks and months; its behavior is quite similar to that of the true malignant ulcer, which is rightly feared. The cancer cells penetrate the surrounding tissue in a way that is as uninhibited as it is ruthlessly destructive and, after a correspondingly rapid transport via the bloodstream, lead to threatening metastases in distant parts of the body and organs. As a result of over-rapid growth, the originally mostly nodular tumor disintegrates and also develops visibly on the outside into an ulcer that no longer heals. The skin carcinoma arises mainly, like the subsequently mentioned basal cell carcinoma, on the face and hands. It should not be forgotten, however, that transitional regions from skin to mucous membrane, for example in the lip–mouth area and in the genital area, can also be the seat of a carcinoma. If skin cancer develops secondarily on a pre-damaged terrain, it is, apart from pigment tumors, almost exclusively skin carcinoma. Even more frequently than skin carcinoma, one encounters the so-called basal cell carcinoma or basal cell cancer, which consists of fundamentally different cell elements.
Basal cell cancer
It lacks crucial characteristics of the real malignant tumor. Although it can cause extraordinary tissue destruction locally, its growth nevertheless remains limited to the area surrounding the site of origin; it does not metastasize and consequently does not exhibit the insidious malignancy of actual cancer. This can be recognized not least by the fact that its increase in size only becomes apparent in months and years. Not infrequently, basal cell carcinomas also occur in the majority at an older age, occasionally also on the generally not freely worn body skin.
Malignant melanoma
By far rarer, but also more dangerous than the first two clinical pictures, is malignant melanoma, which is composed of pigment-containing cells; it usually grows unexpectedly quickly and very soon forms metastases in its own environment, the associated lymph glands, and in other organs. If there is a justified suspicion of the presence of a malignant pigment tumor, both caution and haste are required, because the prognosis is about 50 percent worse than for other types of skin cancer. The severity of the melanoma disease and the success rate of melanoma treatment justify greater concern, but should not and must not lead to a rampant fear of melanoma, because malignant melanomas are too rare for this, while benign pigmentary tumors are commonplace. Melanomas occur at least as frequently on the other skin regions as on the face. Since they sometimes arise from degeneration of moles and birthmarks present since birth, it is advisable to consult a dermatologist if such marks suddenly grow, itch, darken, show inflammatory changes and bleed, or if the pigmentation spreads to the surrounding area. He will understand the concern of such patients, even though it may be unfounded; in any case, he will be able to provide them with certainty. Eventually, he may even remove an ordinary pigmented mark once as a precaution.
Causes
Considered as a whole, malignant tumors of the skin are among the most common cancers of all. In addition, they are in the majority so-called age diseases. Thus, they hardly ever begin before the age of twenty; however, their frequency increases continuously until the age of eighty. With the exception of malignant melanoma, for which women are at greater risk, men and women are affected fairly equally. The development of skin cancer is possible at any skin site, but basal cell carcinomas and skin carcinomas develop especially at exposed, exposed areas, i.e. face and back of the hand, a fact which points to the co-significance of external causes of development. These include heat, sunlight, ultraviolet and X-ray radiation, and certain chemicals and substances that promote the development of cancer. Occasionally, skin cancer may also arise from originally benign but chronically inflamed skin lesions and constantly ulcerating, non-healing ulcers. Although the complete spectrum of causes of skin cancer is still as little fully explored and known as that of most other cancers, these few but thousand-fold proven epidemiological data, together with the fact that skin cancer is precisely a cancer of the skin and thus a cancer visible from the outset and easily and directly accessible to radical treatment, nevertheless offer a large and almost always sufficient measure of possibilities for prevention and even more for timely and thus successful treatment.
Treatment and therapy
As with hardly any other cancer disease, the assistance of the sick person himself is not only unusually important, but also easily possible. Anyone who observes scab- and wart-like formations or superficial ulcers somewhere on their skin at a mature age, but especially on the face and hands, which slowly grow larger and still do not heal after six to eight weeks, should become suspicious and consult an expert dermatologist. Skin cancer of a common type is not only easy to detect, but also relatively easy and successful to treat, if done timely and thoroughly. Under these conditions, the success rates – except for malignant melanomas – are almost greater than 95 percent, so that fear of cancer is really unfounded here. Reliable detection generally involves microscopic examination of a small tumor sample taken surgically; for malignant melanoma, different rules apply in this respect as well. In principle, treatment must be radical, i.e. the cancerous tumor is surgically removed or destroyed with appropriately effective radiation. Occasionally, locally or generally effective chemical-pharmaceutical remedies may also be used. The more harmless the skin cancer is, the more the treatment can take into account individual peculiarities of the patient and his tumor; the more dangerous it seems, the more rigorous the removal must be.Of course, skin cancer in its various variations and gradations is also eventually and ultimately a very serious malignant disease, but it can be seen early and caught in time. This peculiarity offers an almost unique chance of success for the patient, as well as for the physician in the entire fight against cancer.
