The prognosis in cancer of the skin depends on several factors- first, the type of cancer; second, the stage of the disease; third, the situation of the tumor; and last, the skill of the physician who has charge of the case.
In the majority of instances the various so-called precancerous conditions and benign tumors do not become malignant, with a few exceptions. Xeroderma pigmentosum always becomes malignant, and cutaneous horns are very apt to do so. Probably from 5 to 10 percent of all senile keratoses, especially when situated upon the face, develop into cancers. When one considers the enormous number of pigmented moles that exist, it is evident that a very small percentage of them cause trouble, except when subject to chronic irritation, and then the percentage cannot be very high. The so-called nevi, including the pigmented ones and the very vascular ones, very rarely become malignant, but occasionally do. On the other hand, the lesions resulting from tar irritation and from the x-rays very frequently undergo cancerous degenerations. Inflammatory lesions only exceptionally become malignant; perhaps more cases of lupus vulgaris undergo this transformation than any other inflammatory conditions. The common leg ulcers very exceptionally degenerate.
And yet it must be remembered that every abnormality of the skin is a potential cancer, and that cancer practically never originates except upon the site of some pathological condition, be it congenital or acquired.
In cases of prickle-celled cancer, even upon the lip or penis, the prognosis is good if the cases are seen early and if a complete operation is then performed. Bloodgood* states that 40 percent of all cases of prickle-celled cancer, no matter if situated upon the tongue or other mucous membranes, and no matter how extensive, have been cured permanently at the Johns Hopkins Hospital. And Bloodgood does not consider a case cured if it remains alive six months after operation; he is more exacting. In early cases of cancer of the lip at least 90 percent should be cured by a complete operation, and about 70 percent of the late cases. In cancer of the other portions of the skin of the body a very high percentage should be cured if taken in time, and, in considering all classes of cases, the percentage of cures should be well over 50 percent.
*Bloodgood: Amer. Jour. Med. Sc., 1914, cxlvii, 76.
In Bloodgood's series of cuboidal-celled growths the percentage of cures was only 33 percent, but this included many tumors of all stages and locations. If seen early, the percentage of permanent cures should be much higher than that of the squamous-celled neoplasms.
Of the baso-celled growths 70 per cent have been permanently cured, and these figures include even the inoperable cases. When the growth is not over 2 cm. in diameter, 100 percent should be cured by a sufficiently radical treatment. In the more advanced cases, or where there is invasion of some of the natural openings of the face, the outlook is not so good, but nevertheless is not always hopeless by any manner of means.
In regard to sarcoma, Bloodgood furnishes us with some most interesting statistics. In six cases of "perithelial angiosarcoma" arising from a congenital nevus, there was but one cure; in eight similar cases, but arising de novo, there was not one cure. Twenty cases of sarcoma developed in scars; of these eight were cured, five lost track of, and the reminder not cured. '1 In every one of these cases the growth in the scar had continued one or more years, so that in every case there was sufficient clinical indication for an earlier intervention. Now, if the probability of a cure be 50 percent in late intervention, we can be quite sure that it will be much greater in early intervention." In nine cases of sarcoma of the skin there was a history of a preexisting fibroma, and only five of these cases have remained well.
The multiple sarcomata vary in malignancy. In the small round-celled cases the outlook is hopeless, but in the Kaposi and Spiegler-Fendt types the outlook is better, although most of the patients having the Kaposi variety eventually die, yet the patient may survive for a number of years.
The prognosis in the cancers arising from the various appendages of the skin, as well as the endothelial group, is fairly good, for a sufficiently broad local incision will usually cure both of these conditions.
The stage of the disease has, of course, a most important bearing, for an early prickle-celled cancer is much easier to treat and has a much better outlook than a very advanced basal-celled neoplasm. With the exception of the nevocarcinoma group, the prognosis of all early tumors is good, for every tumor is curable in some stage of its existence. Even in fairly well-advanced growths of almost any variety the prognosis is not absolutely hope: less if the tumor is so situated that a complete operation can be performed.
The location of the neoplasm is very important in determining the outcome, as well as the utility of the organ involved. In cancer of the face there is an unfortunate tendency to do too limited an operation because of the fear of deformity. Upon the eyelids or ears a complete operation is not only difficult, but very deforming. Upon the lip the prognosis is generally good, for, as already stated, the figures from Mayos show that over 80 percent of the early cases can be permanently cured, and about 70 percent of the late and recurrent cases give good results if submitted to a radical operation.
Tumors situated upon the limbs or body can usually be cured even at a fairly late stage, for here a large operation can be done with the more than fair chance of removing all of the cancerous tissue, even if some of it be in the lymphatic glands. Upon the penis the outlook is not so good, for cure demands the complete removal of that organ and of the neighboring lymphatic glands, and even then only about half of the early cases are cured. In the rare tumors of the basal-celled variety the outlook is much better, for local removal will generally cure.
The skill of the operator is essential. In the first place, the surgeon or dermatologist should be able to accurately diagnose his case before operation, preferably without the use of a biopsy, for, as already pointed out, a biopsy may be dangerous, inasmuch as it may allow cancer cells to escape into the cut blood vessels or lymphatics. In some cases it is impossible to diagnose a growth until the time of operation, and then a surgeon should be sufficiently skillful as a gross pathologist to immediately tell what the character of the tumor is, and hence how extensive an operation is necessary.
Complete operations should be done in one sitting, for second operations are always dangerous for two reasons-first, because of the effect upon the general health of the patient, and second, there must of necessity be a break in the chain of complete removal, and a few cells may be left at the dividing line between the tissue removed at the different operations.
In addition to this, the surgeon must know just how much tissue to remove and just how to remove it, as well as understanding how prolonged an ordeal the patient can stand.
It is frequently the fault of the physician that the growth is not removed at an early date; the diagnosis of cancer must always be proven or disproven as soon as the growth appears, and the expectant plan of treatment usually leads to very bad results. Fortunately the profession has awakened to the danger of the so-called precancerous conditions, and the laity, as a result, are much better informed than they formerly were. Every surgeon has commented on the number of patients suffering from still benign afflictions of the skin applying for advice and treatment. This one fact is the most hopeful sign that we have today as to the possibilities of permanent results in the field of cancer therapy.
The so-called cancer quack is one of the menaces that today faces the public. The quack is in the field simply for the money that he can secure from unfortunate patients, and in 99 percent of the cases he is absolutely without conscience as to the manner in which he secures this. He is perfectly willing to tell a patient that any kind of a lesion is cancer and needs immediate and expensive treatment; he is absolutely ignorant regarding pathology, and makes no attempt to keep track of his results, except in the hope of securing more money. It is surprising to see how many of the hospital patients have had treatment from this group of men, and then eventually submit to a grave operation because of the loss of time.
In conclusion, the results in the treatment of skin cancer are much better than they formerly were, and will become much better as advice is sought earlier.