Fig. 95
Rat with primary cystosarcoma of thyroid; cage infection in previously healthy animal kept in cage formerly occupied by rat with same condition. (Gaylord and Clowes, Jour. Amer. Med. Assoc., January 5, 1907.)
Fig. 96
Rat with tumor produced by transplantation from that represented in [Fig. 95]. (Gaylord and Clowes, loc. cit.)
Gaylord’s organism is best demonstrated by the Levaditi silver method, but can be seen by experienced observers in the living fresh state. It measures from 2.5 to 7.8 microns in length, and the individuals have from four to thirteen closely packed abrupt turns. The organism measures 0.6 micron in diameter. Thus far it has been impossible to stain it with any of the aniline stains, which characteristic appears to distinguish it from the organism described by Borrel and Loewenthal. Calkins has also found this organism in a spontaneous mouse tumor in New York. The distribution of the organism in the growing periphery of the tumors, when considered in the light of Fischer’s work with Scarlet-R, would make it appear not impossible that the organism bears an etiological relation to the tumors in which it occurs.
In the light of the well-authenticated cases of cage infection and the evidence of immunity now definitely determined, the way should be prepared for the discovery of the organism or organisms of cancer. At present this organism would appear strongly in evidence as its cause.
The microscopic picture may explain considerable in regard to the future as well as the past. For instance, in a case of sarcoma the presence of small, round cells, and especially of pigment, bespeaks a degree of malignancy which probably nothing yet known can baffle. A chemical examination of the tumor after removal may make the surgeon alert regarding the future of the case, according to the amount of glycogen contained within the mass, since the glycogen content is in direct proportion to its malignancy. For a while some reliance was placed upon the percentage of urea elimination, but this is influenced by so many factors as to have proved unreliable.
The relations which cancer bears to other diseases are of considerable interest. Those between cancer and trauma have been discussed; tuberculosis perhaps is the condition which, next to pure local irritation, predisposes to cancerous invasion. The transformation of tuberculous into cancerous lesions can be best appreciated where it can be most readily inspected, i. e., on the skin, and it is well known that lupus lesions frequently undergo this change. This is also true of large ulcers, which may undergo a direct transformation into epithelioma, or pass through the intermediate stage of tuberculous infection. Cancer in tuberculous lymph nodes is also a matter of interest. Again, cancers and tuberculous lesions may exist side by side in the same organ, as in the lung or the brain. Distinct sarcomatous nodules have been found in infiltrated lungs and alongside of tuberculous cavities, while cancer of the face will not infrequently be found associated with tuberculosis of the cervical lymphatics. Lubarsch has claimed that 4 to 5 per cent. of tuberculous patients suffer also from cancer, and that about 20 per cent. of cancer patients suffer from tuberculosis.