ies. In many cases, especially those in which ulceration has occurred,
the addition of pyogenic infection may also be concerned in the failure
of health.

_Treatment._--Removal by surgical means affords the best prospect of
cure. If carcinomatous disease is to be rooted out, its mode of spread
by means of the lymph vessels must be borne in mind, and as this occurs
at an early stage, and is not evident on examination, a wide area must
be included in the operation. The organ from which the original growth
springs should, if practicable, be altogether removed, because its lymph
vessels generally communicate freely with each other, and secondary
deposits have probably already taken place in various parts of it. In
addition, the nearest chain of lymph glands must also be removed, even
though they may not be noticeably enlarged, and in some cases--in cancer
of the breast, for example--the intervening lymph vessels should be
removed at the same time.

The treatment of cancer by other than operative methods has received a
great deal of attention within recent years, and many agents have been
put to the test, _e.g._ colloidal suspensions of selenium, but without
any positive results. Most benefit has resulted from the use of radium
and of the X-rays, and one or other should be employed as a routine
measure after every operation for cancer.

It has been demonstrated that cancer cells are more sensitive to radium
and to the Rontgen rays than the normal cells of the body, and are more
easily killed. The effect varies a good deal with the nature and seat of
the tumour. In rodent cancers of the skin, for example, both radium and
X-ray treatment are very successful, and are to be preferred to
operation because they yield a better cosmetic result. While small
epitheliomas of the skin may be cured by means of the rays, they are not
so amenable as rodent cancers.

Cancers of mucous membranes are less amenable to ray treatment because
they are less circumscribed and are difficult of access. In cancers
under the skin, the Rontgen rays are less efficient; if radium is
employed, the tube containing it should be inserted into the substance
of the tumour after the method described in connection with sarcoma--and
another tube should be placed on the overlying skin.

In the employment of X-rays and of radium in the treatment of cancer,
experience is required, not only to obtain the maximum effect of the
rays, but to avoid damage to the adja