The conclusions concerning the nature of
Infective Sarcoma which have been arrived at, as a
result of this investigation are:-
1. That Infective Sarcoma is a general disease characterised by the production of a local lesion,
possessing the histological structure of an
2. That it is caused by an intracellular virus, conveyed by contagion from a living cell to a living cell.
3. That the tumours formed after natural infection,
probably consist of cells entirely derived from
the tissues of the host.
4. That the nature of the virus cannot be detected,
(a) cannot be revealed by any method of
(b) does not pass through a Berkefeld
(c) is not an ultramicroscopical microorganism.
(d) cannot be isolated apart from the
(e) is not a Spirochete.
5. That the disease can be reproduced readily by
subcutaneous inoculation into animals of the
6. That by the same method, it can be reproduced in
7. That the tumours following subcutaneous inoculation are created from the cells introduced,
live, and by a process of direct contagion,
lead to the formation of additional tumour
cells, from the connective tissue cells of the
8. That it grows by multiplication of the cells thus
formed, combined with a limited formation of
additional tumour cells, from the tissues of
9. That this latter ceases, with the development of
the power of increased resistance on the part
of the host, and a capsule is thus formed around
10. That the tumours disappear by gradual cytolysis
associated with the presence of, and probably
caused by, lymphocytes and polyblasts.
11. That the growth of the tumour is accompanied by
a gradual increase in the number of mononucleated
cells in the circulation.
12. That immunity follows spontaneous recovery.
13. That this is brought about by a similar process,
occupying a much shorter duration of time - a
cytolysis of the tumour cells accompanied by,
and probably arising from, the presence of
lymphocytes and polyblasts.
14. The growth of the tumour is associated with the
development of a toxin, which can be isolated
from it by filtration, and produces interstitial nephritis.
15. That the results of this investigation, emphasise
the present unsatisfactory class faction of
neoplasms, which include a heterogeneous collection of pathological processes, and indicates the probability that, in the near future,
a differentiation will be possible, of processes that are really neoplastic, from those,
that are merely reactive attempts by the host
against an invading virus.