SPONTANEOUS REGRESSION OF CANCER
by
D. W. Smithers
ONLY
A FEW years ago anyone talking
to you
about the
spontaneous regression of tumours would probably have started
by saying
what he meant by " spontaneous " and what he meant by " regression "; he would then have laid down a set of postulates
and after taking away all doubtful cases would have ended up with
little to show for his efforts. This cautious approach
was perhaps the best
way with an unusual and poorly
understood phenomenon. However, the study of some of the unusual behaviour patterns in cancer has contributed a great deal to its better understanding, and if too much is discarded through
caution we may be left with nothing
worth investigating. In the last three months
what I believe are the first two books devoted solely to the subject
of Spontaneous Regression in Cancer have been published (Boyd,
1966; Everson and Cole,
1966).
It appears
that at last this interesting phenomenon may be be
coming an acceptable subject
for discussion.
Since most consideration of spontaneous regression in
cancer has been devoted to well-established
malignant disease, in order to eliminate mis diagnosis as a source of
confusion, metastatic regression, which might be expected to be rare, has been looked at more often than early regression
of primary tumours, which might be expected to
occur more often.
Early regression is
of particular interest
at the moment when the value of cervical cytology, for instance, is under review and the natural history of"
carcin oma in situ " has still
to be clarified.
The chief reasons for taking interest
in a rare phenomenon like spon taneous tumour regression are, first, that it may help us towards a better
general understanding of the neoplastic process and, second,
because it may lead us to a better particular understanding of those tumours which
may behave in this way both as to their origin and as to the methods
most suitable to their control. If a tumour
can regress spontaneously on rare occasions there
is reason to hope
that it may be induced to do so more often when this behaviour is better understood.
It may be misleading to discuss spontaneous regression as a tumour behaviour pattern in isolation. We should be interested in the whole range of unusual tumour performance, and in how they may be inter related. Spontaneous regression should be considered in the context of the long periods of development which some tumours exhibit and their
conditional persistence, of multicentric origin,
progression, maturation and of metaplasia. The
fact that tumours
vary in their behaviour, not only from one to another, but in one tumour from time to time is a most important factor worthy of detailed investigation.
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SPONTANEOUS REGRESSION OF CANCER
A biologist may well consider
that fundamental cancer research
is chiefly concerned with the study of tissue homeostasis, and that it involves investigation of the way in which normal tissues are controlled and of how
control of growth and replacement may become disturbed. Spontaneous
tumour regression is of particular interest to those who approach
the problem
in this general way since it suggests that there are ways in which normal controls may be re-established at times.
Site frequency
In the book just published by Everson and Cole (1966) the tumour
types most commonly detected
undergoing spontaneous regression in order of frequency
were as follows:
Adenocarcinoma of the kidney
Neuroblastoma Malignant melanoma Choriocarcinoma
Carcinoma of the bladder
Soft tissue and bone sarcomata.
This group of six main tumour types accounted for over 70 per cent of
their collected, verified cases of spontaneous regression. Carcinomas of the colon and rectum, ovary, testis and breast were the next commonest
group; all others were great rarities. Everson and Cole did not consider spontaneous regression of skin tumours, however,
a matter which it is
difficult to assess but which may be quite common,
nor the early mani
festations of carcinoma of the cervix, where again the natural
history and incidence of regression is not yet clearly known.
They
also omitted all consideration of the lymphomas where spontaneous remissions are common, but possibly of
a rather different character.
Professor Smithers
then referred to the paper by him published in Clinical Radiology in
1962, and elaborated on the possible reasons
for spontaneous regression in the com
moner tumours undergoing this change, showing
a series of slides illustrating a number of
these cases.
He referred
to the growing interest in the kidney as an endocrine organ,
to the work of Dr. Bloom (1964) on the hormone
treatment
of adenocarcinoma of
the kidney and suggested that spontaneous regressions in this group might be hormone induced. Total tumour volume
could also
be of importance here since most of these regressions had been in metastases following
removal of the primary tumour.
With relation
to the neuroblastomas he also referred to regression in retinoblastomas and other embryonal tumours
in children,
suggesting that some of these at least
might take place by
way of the process of maturation.
With malignant
melanoma he again suggested the possibility of a hormone effect and referred to published examples
of regression during pregnancy.
With the choriocarcinomas he
suggested that there were
two possible methods
of spontaneous regression, one hormone induced (here he referred
to a patient of Mr. Peter Greening who had had regression of multiple metastases following a pituitary implant of radioactive yttrium)
and the other through immunological reaction (where he referred to
the work of Dr. Rider in Toronto).
The bladder tumour
regressions seemed all to have followed
ureteric transplants and seemed likely
to be human examples of conditional tumours,
a well known phenomenon in laboratory animals.
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D. W. SMITHERS
Lastly, he referred to the soft tissue and bone
sarcoma regressions, saying that no explanation had yet been put forward
to account for
these although it might be that some
were indeed embryonal tumours. He noted with interest that in the small collections of patients who had had a successful
removal of a solitary metastasis in the lung a number had been
from primary osteogenic sarcomas and testicular teratomas.
He stressed
in conclusion that
the study of the phenomenon
of spontaneous regres sion in malignant disease
was well worth pursuing because of the opportunity it pro vided for better
understanding
of the neoplastic process
and the
hope it supplied for better therapeutic control.
REFERENCES
BLOOM, H. J. G. (1964) Hormone Treatment of Renal Tumours: Experimental
and Clinical Observations, in Tumours of the
Kidney and Ureter, edited by Sir Eric Riches. London, Livingstone.
BoYD, W. (1966)
The Spontaneous Regression
of Cancer. Springfield, Illinois: Thomas. EvERSON, T.
C., and COLE, W. H. (1966) Spontaneous Regression of Cancer. Phila
delphia and London,
Saunders. SMITHERS,
D. W. (1962) C/in. Radio/.13, 132.
THE CARE
OF
THE
TERMINAL STAGES
OF
CANCER
by
Cicely M. S. Saunders
" THE TERMINAL STAGES
of cancer " may be defined as the time when all active
treatment becomes increasingly irrelevant to the real needs of a particular
patient. Many of the points Iwill
mention
are
of
course applicable to the time when palliative radiotherapy, chemotherapy and nerve
block and section
are used, but I am concerned
now with the patient for whom these treatments are no longer helpful.
It may be difficult to decide that this
moment has
arrived, but it is most
important that
we should
recognize it and that we should remember
that Sir Stanford Cade's question,
" What is the relative value
of the various available methods
of treatment in this particular
patient?" (Cade, 1963), is just as pertinent now as at any other stage of a patient's
illness. We need also to be aware that
this answer
should frequently be decided
in discussion by the whole group
who have been concerned
with the patient's previous
care.
Sadly, the terminal
stage
could
also
be
defined as beginning at the moment when
someone says, "There is
nothing more
to be done", and then begins to withdraw, more or less subtly,
from
the patient.
These
people are very well aware when this happens. On admission to such a unit as that in which I have been working they make remarks
that reveal this all too clearly. "It seemed so strange,
no one seemed to want to look at me," said one woman.
The ward round had gone past the end of the
bed, the
three-month follow-up had been given
when she knew her condition
was changing week
by week and finally the family doctor had sent the message about admission through a relative.
" To imply that nothing
helpful can be done is inexcusable and seldom if ever true" (Smithers, 1960). Nor do we realize how much we can do simply
by coming to see the patient when we feel that we have nothing to offer.
We fail to understand
what patients
really expect of us. They
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