Inaccuracy of ultrasonography and MRI in staging early prostatic cancer

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conclusions were always backed up with objective research. Hisinterest in ethology led him to enlist the support of Konrad Lorenz,Niko Tinbergen, and Robert Hinde. During Bowlby’s lifetime,psychoanalysis came under such heavy attack from both

behaviourists and biologically minded psychiatrists that it was indanger of disappearing. Bowlby rescued the baby whilst letting thebathwater go, and, more than anyone else, proved that

psychoanalytical insights could receive scientific backing. His workhas inspired a great deal of valuable research.John Bowlby was an excellent physician in the widest sense of

that word. Anyone in distress who turned to him would be sure offinding an expert who, at the same time, was a warm, caring humanbeing with a unusual capacity for attentive listening. Despite hisachievements, he was not in the least pompous. To the end of hislife, he was always prepared to learn from others and to entertainnew possibilities. Anyone who was present at the launch of his lastbook at the Tavistock Clinic will remember his courageous speech,made from a wheel-chair at the age of eighty-three, which was asclear and cogent as if he had been in good health and forty yearsyounger.

Although his achievements have been widely recognised, I stillthink that the importance of his work has been underestimated.Biological psychiatrists are suspicious of anyone calling himself apsychoanalyst; and the psychoanalytical establishment thought thatBowlby was not really "one of us". Bowlby was unclassifiable, likeeveryone of independent mind, and this has delayed the finalrecognition of his proper status. To my mind, he is one of the threeor four really great psychiatrists of the twentieth century.

Anthony Storr

Noticeboard

Avoiding unnecessary patient exposure toradiation

About 87% of the total collective dose of ionising radiation that thepopulation of the UK receives from man-made sources come fromdiagnostic X-rays. About half of this contribution is unnecessary,says a reportl by a joint working party from the Royal College ofRadiologists and the National Radiation Protection Board

published last week, which lists measures for reducing the currentannual collective population dose of ionising radiation from medicalX-rays by about 7500 man Sv per year-an excess that the workingparty says could be responsible for a hypothetical 100-250 of the160 000 cancer fatalities that occur each year.The report estimates that about 20% of X-ray examinations are

unnecessary because the probability that they will provideinformation useful for clinical management is extremely low, andthat elimination of such examinations would give a potential annualcollective dose saving of 3200 man Sv. The report recommends aCollege booklet Making the Best Use of a Department of Radiology,which contains referral guidelines for twelve categories of

radiological examinations covering over 70 important clinicalcircumstances and which has been introduced, as part of a researchproject, into five NHS hospitals, where it has been accepted ashospital policy. Special mention is made of the need to justifymammography screening in women aged over 50, employment-related chest screening, and the use of computed tomography (CT).The number of CT scanners has doubled in the past 5 years in theUK to about 200. The working party says that all requests for a CTscan should be vetted by an experienced radiology. CTexaminations carry high-dose implications, which the workingparty thinks not all radiologists are fully aware of, so it recommendsrapid publication of the results of an NRPB national survey on CTpractice and patient doses still in progress. Savings would also beachieved by good organisation and quality control, because thereasons for a large proportion of repeat examinations are no morethan the mislaying or poor quality of the original film.

Other suggestions for minimising patient dose include reducingthe number of films per examination to the median value or less ofthat obtained in a survey of 20 hospitals done in 1983, reducing

fluoroscopy time to median survey value or less, and reducinghospital mean doses to the survey third quartile value or less. The1983 survey showed that entrance skin-doses per film for nominallythe same type of radiograph varied 5-20 fold within and betweenhospitals, so as a first step the report recommends that hospitalsshould regularly monitor levels of entrance surface dose in eachX-ray room for a few common X-ray procedures. The report alsolists radiographic projections that should not be included

routinely--eg, an axial view when a skull X-ray is requested.The third group of measures recommended is the introduction of

dose-saving equipment, with prime consideration being given torare-earth screens, to optimum operation of film processors andimage intensifiers, and to carbon-fibre components-measures thatcost from nothing to c280 per man Sv saved, and which werediscussed in The Lancet two years ago.2The recommendations made in the report are common-sense

measures and most can be implemented without much difficulty.However, pressure from women aged under 50 for mammographicbreast screening may make it necessary for screening services,especially those in the private sector, to reassess their policiescarefully.

1. Patient dose reduction in diagnostic radiology. Report by the Royal College ofRadiologists and the National Radiological Protection Board. Documents of theNRPB, 1990, vol 1. London: HM Stationery Office, 1990.

2. Anon. Radiation protection in the UK: an opportunity missed. Lancet 1988; ii: 315-16.

Inaccuracy of ultrasonography and MRI in stagingearly prostatic cancer

Computed tomography cannot identify prostatic disease, so it hasbeen replaced by ultrasonography and magnetic resonance imaging(MRI) for diagnosis and staging. Early assessments, on smallnumbers of patients, had yielded promising results. However, theencouraging results have not been confirmed in a multicentre studylin which 230 patients thought clinically to have localised prostatic’cancer were assessed with transrectal ultrasonography and MRIbefore undergoing radical prostatectomy. Ultrasonographyaccurately staged 66% of advanced disease and 46% of confineddisease; the corresponding figures for MRI were 77% and 57%.Neither technique could reliably differentiate microscopical localfrom advanced disease in patients who seemed clinically to havesurgically resectable disease. For every 100 patients with ultrasoundresults suggesting extension of disease beyond the prostate, 37 werefalse positives; the proportion falsely diagnosed by ultrasonographyas having confined disease was 51 %; the corresponding figures forMRI were 29% and 37%. Furthermore, ultrasonographyidentified only 59%, and MRI 60%, of malignant lesions that hadone dimension exceeding 5 mm. Clearly at the present stage ofdevelopment ultrasonography and MRI are not accurate

techniques for staging early prostatic cancer. Does the solution lie inrefinements of these techniques, as those who reported the studyseem so strongly to believe?

1. Rifkin MD, Zerhouni EA, Gatsonis CA, et al. Comparison of magnetic resonanceimaging and ultrasonography in staging early prostate cancer N Engl J Med 1990;323: 621-26.

Eisai London Research Laboratories at UCL

Eisai, a Japanese pharmaceutical company, is investing more than50 million over the next 15 years to build and run a new researchlaboratory for neuroscience, especially the study of diseases of thecentral nervous system, on the University College London campus.The laboratory will be part of a new research centre at UCL that willinclude a Medical Research Council building for cell biology. Theinitial investment of C 12 m will go to the building and equipment ofthe laboratory, expected to open in the autumn of 1991. After 50years Eisai will freely transfer ownership of the building to UCLwhich, with its Centre for Neurosciences, established in 1979, waschosen by Eisai for its experience in this area. Scientists recruited forthe laboratory will hold part-time teaching and research posts at theCollege.