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RECURRENCE OF RECTAL CANCER IN PATIENTSMANAGED BY STAPLED ANASTOMOSIS

SIR,-The letter from Mr Johnson and Mr Celestin (July 28,p 219) is a timely warning that the efficacy of restorative rectalresection for cancer needs to be kept constantly under review. I havejust completed a survey of 220 cases, consecutive and unselected, ofrestorative rectal resection in a seven-year period; the full detailswill be published elsewhere. My policy was to use restorativeresection whenever it seemed to give a very good chance of completeclearance of the growth. Abdominoperineal excision was done inonly 1 out of 10 cases where the growth lay within 15 cm of the analskin.

My yardstick for comparison has been the 1963 report by Morsonet al on 1763 cases of rectal cancer treated by total rectal excision.In that series 80% of pelvic recurrences were detected within 2 yearsof the operation. In my smaller series 87 operation survivors havebeen followed up for at least 2 years or until pelvic recurrence.Morson et al found a pelvic recurrence rate of 205/1796 (11.4%).The pelvic recurrence rate in my series was 13/87 (15%). Thisdifference is not significant. Admittedly the follow-up has beenshort, but this may be offset by the fact that the presence of afunctioning anus makes the symptoms of recurrence appear earlierand its diagnosis easier than in cases where the rectum has beencompletely removed. The series was of all cases, including those inwhich the operation was thought at the time not to be "curative". Inevery case the rectal stump was irrigated with cytotoxic solutionbefore division of the bowel.The stapler makes the operation easier and quicker but did not, in

my hands, have any effect on the suture line leak rate. The latter wasfavourably influenced by the routine use of antimicrobial

prophylaxis-54% before and 32% after its introduction (radio-logical measurement). Neither of these advances is likely,unfortunately, to have influenced the incidence of recurrent cancer.These results suggest that the tremendous boon of avoiding a

colostomy can be offered to most patients with rectal cancer,without compromising the chance of cure.16 Maid’s Causeway,Cambridge CB5 8DA R. E. B. TAGART

1. Morson BC, Vaughan EG, Bussey HJR. Pelvic recurrence after excision of rectum forcarcinoma. Br Med J 1963; ii: 13-18.

SCREENING FOR BREAST CANCER

SIR,-In trials comparing treatment for breast or any other cancerthe survival time is the interval between first treatment and death.In early breast cancer treatment usually begins after the definitivediagnosis, and the intervals treatment-to-death and diagnosis-to-death will be much the same. In a randomised trial, any difference insurvival will be due to deaths occurring later in one of the groups.However, with screening the diagnosis-to-death interval may beprolonged because of later death and/or earlier diagnosis, and thecrucial question is whether earlier diagnosis really postpones death.Have the two case-control analyses of screening programmes in theNetherlands (June 2, pp 1222 and 1224) shown such an effect?Both of these studies took as "cases" patients who had been

diagnosed as having breast cancer after they had been offeredmammography, and who subsequently died of the disease. InNijmegen, women aged 35-69 were first offered screening fromJan 1, 1975, onwards, and women aged 70 + were offered screeningfrom 1977 onwards. The acceptance rate for the 35-69 age group inthe first round of screening (1975-76) was almost 85%, but in the70 + group (in 1977-78) it was only 34-5%. In Utrecht, screeningbegan in 1974, being offered to women aged 50-64 at that time. Theacceptance rate was 72%.As "controls", women born in the same year were selected, there

being 5 controls for each case in Nijmegen and 3 controls per case inUtrecht. Of the 46 Nijmegen cases, 26 (57%) had acceptedscreening, but 162 (70 - 4%) of their 230 controls had been screened.In Utrecht, only 9 (20%) of the 46 cases but 59 (42-8%) of 138controls had been screened. Clearly, screening had been done muchless often in the cases than the controls, and this difference was onthe border of significance at the 5% level in Nijmegen and was

definitely significant in Utrecht. Does this mean that screening isdelaying or preventing death from breast cancer in these cities?The deaths analysed had to have occurred in 1975-81, so the

maximum survival of any case is 7 years in Nijmegen and 8 years inUtrecht (ie, a case diagnosed just after the start of the screeningprogramme and dying late in 1981). Year of death is not presented inthe Nijmegen report, but almost half the Utrecht cases had died by1979 - a maximum survival (if they had been diagnosed in 1974) of6 6years. These cases are therefore early deaths from breast cancer,cases with a short interval between diagnosis and death. Sincescreening will tend to make diagnosis occur "earlier" thanotherwise (eg, self-examination prompting a woman to seek medicaladvice), it would be expected that many more patients whose cancerhas been detected by screening will have longer diagnosis-to-deathtimes than patients whose cancer has been detected by feeling alump in the breast. Therefore, if patients with short diagnosis-to-death times are chosen for study (as these two papers have done), onewould expect a deficit of cases diagnosed by screening, and theshorter the diagnosis-to-death interval the greater this deficit shouldbe.

So, these two studies have shown results which can only beinterpreted to mean that patients who have short diagnosis-to-deathtimes are unlikely to have had their breast cancer diagnosed byscreening. Screened patients will be likely to have longer diagnosis-to-death intervals, but this does not necessarily mean that death isbeing delayed too-ie, in addition to diagnosis being made earlier.A curious feature of the results is that screening was accepted in

fewer of the controls than in the whole population offered screeningin these two cities-70-4% of the controls, compared with anacceptance rate for the 35-69 age group in Nijmegen of nearly 85%(but only 34 - 5% in the 70 + group), and only 42 - 8% of the Utrechtcontrols compared with an overall acceptance rate of 72%. The age-specific acceptance rates presented in the Nijmegen paper suggeststrongly that low acceptance of screening is a feature of older age,but the Utrecht paper does not present data enabling this to becorroborated for that study. So, we can add that these two studieshave considered in the main older patients with short intervals fromdiagnosis to death.Once more then we have findings which do not answer the

fundamental question-does screening merely prolong the

diagnosis-to-death interval by making diagnosis earlier and not bydelaying death? If all screening did was just this, one would alwaysexpect patients with longer diagnosis-to-death intervals to havebeen diagnosed by screening, and patients with shorter interval notto have been so diagnosed.There really is no alternative to a randomised study if screening is

to be properly assessed. Case-control analyses, unfortunately, canbe very difficult to understand. These two studies seem to suggestgreat benefit from the use of mammography on all women over theage of 35 or 40, but close scrutiny shows that the results are artifactsof case selection. Case-control studies might seem to be impressivealternatives to randomised studies, but they are not.

King’s College School of Medicineand Dentistry,

London SE5 M. BAUM

Charing Cross Hospital Medical School,London W68RF K. D. MACRAE

INTRADUCTAL BREAST CANCER

SIR,-Intraduct carcinoma of the breast represents a smallfraction of breast disease, and its importance lies in the potential forsurgical cure in the face of likely malignant progression.’ As

emphasised by your July 7 editorial, the great difficulty lies indiagnosis of the preinvasive phase. In the absence of a reliablescreening method, most clinicians have to depend on three modes ofclinical presentation-an associated breast lump; Paget’s disease ofthe nipple (surprisingly ignored in the editorial); and nippledischarge (which need not necessarily be bloodstained). Theimportance of the last two must not be forgotten.

I have reviewed the histological reports of 2667 breast biopsiesunder the care of one consultant between 1967 and 1983 and