RADIOACTIVITY IN MILK AND BONE

RADIOACTIVITY IN MILK AND BONE

833 Letters to the Editor PROTAMINE IN BREAST CANCERS SIR,-We feel that Dr. Jolles (Oct. 5, p. 736) does us less than justice when he suggests t...

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833

Letters

to

the Editor

PROTAMINE IN BREAST CANCERS SIR,-We feel that Dr. Jolles (Oct. 5, p. 736) does

us

less than justice when he suggests that we are unaware of the complexities of cancerous stromal growth. In fact, many of the points which he mentions have already received attention in the previous publications listed and others have not been neglected during the course of the studies very briefly recorded in our preliminary communication. The complexities are even greater than Dr. Jolles suspects; for heparin, which he mentions in this context as an anticoagulant, only acts to prevent clotting in the presence of its co-factor which is much reduced in the blood of most cancer cases and almost completely absent in some.! In the absence of its co-factor, heparin acts as a fibrinogen precipitant in suitable circumstances2 and may even promote clotting. In our studies we have not been concerned to apply " anticoagulant therapy " which, from our point of view, is a misnomer. Our aim has been to neutralise the labile coagulative factor which diffuses from cancer cells as they grow. In-vitro tests have shown that protamine combines with and neutralises the factor, and its use in therapy was, therefore, a logical step in the absence of a better alternative which is not immediately available. The order of dosage employed was many. times greater than that used conventionally for such therapeutic purposes as the neutralisation of heparin, and treatment was prolonged, In consequence, it was expected that a sufficient concentration of protamine would reach the tumour to effect an appreciable amount of neutralisation. During the trial no evidence was found that protamine in the form in which we have used it (’ Prolothan A ’) had any anticoagulant or coagulant effect so far as the blood On the other hand, it did appear to was concerned. localise at the site of the tumours as shown by the erythema and regressive changes which it produced in them. These changes were of a similar order to those previously observed by the use of fibrinolytic agents3 which destroy the cancer coagulative factor in vitro. A study of the mast cells and ground substance, in the specimens removed at operation, was made at the time by one of us, and no departure from the usual findings in breast tumours was detected in the mast cells. The ground substance appeared less metachromatic than usual, and this observation, if confirmed, would again point to concentration of protamine in the tumour area. We referred in our article to the fact that protamine combines with acid mucopolysaccharides as well as neutralising the cancer coagulative factor. The work of Dr. Jolles and his associates4 had been studied with great interest when it appeared, because we had some time ago (Dr. Boggust) tested a series of polysaccharide sulphates of composition similar to laminarin sulphate. In the standard test which we use for neutralisation of the cancer coagulative it was found that some of the polysaccharide sulphates have an inhibitory effect which, weight-for-weight, is less than that of protamine. Also, it is apparent that the modus operandi is different because of their very different chemical properties. It is highly probable that laminarin sulphate would show inhibition of the same order, but we have had no oooortunitv of testing it.

factor,

1. Temperley, I. J. J. clin. Path. 1963, 16, 115. 2. Temperley, I. J. Irish J. med. Sci. April, 1963, p. 159. 3. Scientific Exhibition, B.M.A. Meeting, Belfast, 1962. 4. Jolles, B., Remington, M., Anderson, P. Brit. J. Cancer,

1963, 17, 109.

One could, therefore, advance the hypothesis that the results obtained by Dr. Jolles and his associates were attributable to inhibition of the cancer coagulative factor in their mouse tumours. This we would hesitate to do, because our work has been strictly confined to naturally occurring spontaneous cancers in man. Material from human sources has been used throughout in our coagulation studies. The differences, often striking, which are known to exist between the details of the coagulation/ fibrinolytic system in man and other mammals have been so inadequately studied as to make direct comparison, in the complex field with which we are dealing, unjustifiable. School of Pathology, R. A. Q. O’MEARA. Trinity College, Dublin. M. J. O’HALLORAN. St. Luke’s Hospital, Dublin. RADIOACTIVITY IN MILK AND BONE SiR,—The recent statement by Sir John Cockcroft1

about the possible stopping of fresh milk supplies to children at least once during the past two years, because of its high radioiodine content, raises other questions. The Agricultural Research Council has not published the results of radioiodine examinations in milk from the " special areas "2 of Britain-the hills with high rainfall, where nuclear fallout,like the rainfall, is five times or more the national average.33 Should children have been milk from these hills during the period of high given radioiodine content? Canadian levels4 of radio-strontium and radio-cassium in fresh milk in 1963, especially in the summer, have been at record high levels, at which they remain. They are nearly twice the 1962 levels and over twice the 1959 peak. The Canadian level in 1959 was an average yearly figure of 14 ;C of 90Sr per g. Ca, with a maximum of 21, and a minimum of 6.1.5 The average content of 90Sr in whole milk in July, 1963, was 46-4 {J.{J.C per litre. British fallout levels are comparable to the Canadian figures, except that with half-yearly or yearly reports, the British information comes six to twelve months later. There have been no large investigations of radioactive strontium in the bones of infants from the areas of high fallout in Britain. Only 2% or 3% of over one thousand bones examined by the Atomic Energy Research Establishment for the Medical Research Council6 come from children between birth and one year of age in the areas of high fallout. But Dr. J. F. Loutit, of the M.R.C. Radiobiological Research Unit, has shown how an estimate of these levels can be made.’ He has shown that levels of radio-strontium in the bones of infants between birth and one year of age are half that of the level in milk they drink, compared with a figure of one quarter in older children. The recent Canadian report shows that it is probable that milk in areas of high fallout in Britain contains radioactive strontium above a level of 134 {J.{J.C per litre and possibly considerably above this. This means that amounts of radioactive strontium in the bones of infants who are drinking milk from wet areas may well be above the 33-5 {J.{J.C per g. Ca of the Medical Research Council’s " warning level " and the 67 fjC per g. Ca which is the maximum permissible level in the whole population allowed by the International Commission on Radiological Protection.8 1. Guardian, Sept. 30, 1963. 2. Annual Report of Agricultural Research Council Radiobiological Laboratory, 1962-63. 3. Agricultural Research Council: Radiobiological Reports nos. 3 and 4. Strontium 90 in Milk and Agricultural Materials in the U.K. H.M. Stationery Office.

4. Radiation Protection Division of the Canadian Department of National Health and Welfare: August, 1963, and earlier monthly reports. 5. Report of the U.N. Scientific Committee on the Effect of Atomic Radiation. New York, 1962. 6. Assay of Strontium-90 in Human Bone in the United Kingdom. Medical Research Council Monitoring Report Series. H.M. Stationery Office. 7. B.B.C. broadcast, March 2. 1961. 8. Hazards to Man of Nuclear and Allied Radiations. H.M. Stationery Office, 1960.

834 The Canadian report indicates that the bone dose from the short-lived 119Sr, which has been at a high level during the past year, is comparable to that from 90Sr. It can no longer be ignored. It is of interest to compare the rise in the radiation dose from fallout with the decrease in the dose from X-ray exposures.5 Since the Adrian report,9 recommending the avoidance of all unnecessary exposure to X rays, these exposures can be and in some cases have been reduced in three years by two-thirds, and special precautions are taken to avoid, if possible, all exposure to pregnant women and to children. During the same period, exposure of young children to radiation from fallout has more than doubled and is now a major source of manmade radiation exposure.

Two conflicting standards seem to be used. In medical radiography the dose is reduced to the practical minimum, recognising that as there is no threshold and that any dose, however small, may be dangerous. When fallout is considered, a threshold is assumed and many people use the terms " safety " and " danger levels of radiation ". With nuclear fallout now at maximum levels, there may be a hazard in milk from Exmoor, Dartmoor, the Welsh hills, the Lake District, and the Scottish Highlands. Some of this milk is dried for infant foods, which can be given to infants for a year or more. Tins of it may have a long " shelf life ". Should not supplies be stopped during this present period of maximum fallout ? Should not the Agricultural and Medical Research Councils publish monthly up-to-

date information

as

is done in Canada ?

Cricket Malherbie,

Ilminster,

GEOFFREY TAYLOR. ’,‘ An annotation on p. 819 refers to some newly published measurements of radioactivity in milk and bone in the United Kingdom.-ED. L. Somerset.

A COLLEGE OF PSYCHIATRY

SIR,-Dr. Howells (Oct. 5), in his able exposition of the reasons for the formation of a College of Psychiatry, overlooks a number of important points. While most psychiatrists would like to see improvements in the academic standards of psychiatry, and in the representation of its interests, the real question is whether the formation of a college is the best way, in the long run, to achieve these ends. At present, as Dr. Howells points out, the Royal College of Physicians speaks for psychiatrists on various matters, though many psychiatrists feel it is not truly representative of them. It also conducts a diploma examination in the subject, jointly with the Royal College of Surgeons (the profit it makes being, I should have thought, quite beside the point), though this is only one of a number of such diplomas, most of which are awarded by universities. It must first be asked whether-and how-psychiatrists can improve their position in the R.C.P. Clearly the formation of a Faculty within the R.C.P. is unacceptable, and if psychiatrists are to play an active part in the R.C.P. they must do so on an equal footing with other physiI suggest that what is

cians.

most

needed is

a

reform of the

examination, so heavily weighted against psychological and in favour of organic " medicine. It is admittedly unfortunate that the R.C.P. has not adjusted M.R.C.P.

"

itself-and the membership examination-to the changes in psychiatry that have taken place recently. These changes include a considerable increase in the number of psychiatrists; a tendency for psychiatrists to move out of the mental hospitals and into general hospitals, outpatient clinics, and the com9.

Radiological Hazards to Patients. H.M. Stationery Office,

1960.

munity ; more academic units of psychiatry; and more, and probably better, research in the field. Modification of the membership examination along the lines of that for membership of the Royal College of Physicians of Edinburgh seems the obvious course. The latter examination, demanding as it does a reasonable proficiency in general medicine and a specially high standard in the candidate’s own subject, seems a very reasonable sort of higher qualification in psychiatry. Whether psychiatrists are wise at this time to turn their liacks on the R.C.P. and form their own college is highly debatable. The present rather unhelpful attitude of the R.C.P. may well change and the developments in psychiatry that I have mentioned are, after all, very recent. The step that Dr. Howells advocates may in the long run prove very unfortunate, and is unlikely to help the present trend of psychiatry to expand from the mental hospitals and to become more closely integrated with other medical specialties. It should also be pointed out that in the Royal MedicoPsychological Association psychiatrists have an organisation which meets many of their academic needs and is able to represent their interests in a number of fields. With relatively little modification it could meet most of the other needs mentioned by Dr. Howells, without increasing the number of higher qualifications still further. And for the present it is always open to aspiring psychiatrists to take the M.R.C.P. Edin. examination. Royal Dundee Liff Hospital,

Liff, Dundee.

PHILIP A. BARKER.

SIR,-Dr. Howells is greatly to be congratulated on setting forth so clearly the reasons why psychiatry must now have its own college. The decision of pathology -another rapidly growing and increasingly important specialty-to form its own college was a serious, but not mortal, blow to the Royal College of Physicians. At that time you, Sir, warnedof the disturbing effect on Medicine if psychiatrists seceded from the college. What has the college done to avert this disaster, if indeed disaster it is ? What concessions has it made to meet the just claims of psychiatry for a fair say in their own future ? It has called one meeting of its psychiatric members and fellows (a small minority group of psychiatrists in any event) but it has failed to do the one thing necessary to meet the challenge of the times-

change ! It is no longer possible-indeed; it has not been possible these last twenty-five years-to encompass the whole field of Medicine and master a specialty as well. Had the college been prepared to acknowledge this and modify its examinations along the lines of the, Edinburgh M.R.C.P. (for which, incidentally, London is infinitely better equipped than a small city like Edinburgh) it might still have retained the respect and allegiance of both pathology and psychiatry. Its refusal to do so at the right time smacks more of the rigidity of senescence than a genuine desire to maintain the highest standards of medical practice. The Royal College equates consultant status in any medical specialty with possession of its membership-and then makes this diploma virtually unattainable to any psychiatrist working in a mental hospital. It places the future of each specialty in the hands of its Fellows-and then denies fellowship to all but a handful of psychiatrists. It was largely instrumental, as Dr. Howells points out, in framing the Platt report-but failed to nominate a psychiatrist to the working party despite the fact that well over 40% of all hospital beds come under the care of psychiatrists. When I mentioned 1.

Lancet, 1962, i, 1387.