1. Cancer cells, which have a reproductive capacity, may be forced into the adjoining tissue, or find entrance into blood vessels or lymphatics severed during operation, and there continue their activity and produce new lesions.
2. By implantation, cancer cells, already started on their reproductive career, may be transferred to freshly cut surfaces, and there may develop new lesions, favored by the continued derangement of the blood current.
3. Cancer cells may have existed outside of the immediate area which was removed surgically, and so may continue to develop new lesions, being further stimulated thereto by the manipulations attending the operation.
4. We know, finally, that the occasional removal of lesions which are afterwards shown microscopically to be benign, such as adenoma, cysts, chronic mastitis, etc., will sometimes be followed by the development of true cancer, which will then pursue a malignant course.
On the occurrence, therefore, of any lump or lesion which might possibly be or become cancer, the greatest caution should be exercised to avoid all manipulation, lest a spread of the disease should render it more rebellious to treatment. For in the medical management of cancer it is naturally more difficult to cure a patient when there are large numbers of diseased cells, in one or various locations, which are already giving forth their poisonous hormone, vitiating the blood stream.
The New York Board of Health has recently inaugurated a service for the examination of specimens excised from suspected cancer, in order to establish the diagnosis microscopically before surgical operation. There could hardly be devised a more effective plan to increase the mortality from cancer and to render many more cases really inoperable than this one would surely be; for by thus cutting into cancerous tissue and opening lymphatic channels and blood vessels, with the opportunity for absorption of cancerous elements during the necessary delay, metastases would certainly be induced which would render a surgical removal or a dietary and medicinal treatment immeasurably less effective. It is to be hoped that this scheme will be immediately abandoned.
Recurrence of cancer is far more common during the first year after operation than in any other single year, but, as we shall see shortly, there is no time limit when the disease may not manifest itself anew. It is understood, of course, that recurrence depends also largely on the previous duration, extent, and malignancy of the tumor, and exact statistics are very few and imperfect in regard to these matters.
It is well known that not long ago three years was considered as the time at which, if there had been no recurrence, the cancer could be considered as cured, and very many statistics have been based on this period. But with further experience and closer observation, and with more diligent following up cases, it was found that recurrences did take place more or less frequently at subsequent periods, and now the time limit has been arbitrarily extended to five years. This is because the very large proportion of recurrences are in the first year, varying for different locations and conditions from as high as 50 to 80 per cent in different statistics.
But as the patients who have lived out the five-year limit are followed up more carefully, it is found that recurrences do happen all along the following years, so that they are recorded as occurring 6, 8, 9, 20, and 25 years after operation; I have met with many after 3 or 5 years, and even as late as 15 years after operation. The vast majority of cases, however, are not thus accurately followed out, much less reported, and thus far we have few data on which to make accurate statements as to the actual permanent cure of cancer by the knife.
Recurrent cancer, as one constantly observes it, is most deplorable, and many who have had much to do with these cases realize that the distress is often far greater than in other cases in which the disease has run a natural course, without operation and under good medical guidance. The pain attending growths in scar tissue is generally intense and commonly requires anodynes continually and increasingly; these in turn, by disturbing digestion and locking up the secretions, seem to augment the disease. Even with these patients, however, very much may be done to relieve their suffering by proper dietary and medicinal means, with suitable local medication, as I have constantly seen, so that opiates need be but little used.