This study compared the accuracy of interpretation by surgeons and radiologists of 1053 women who had two view mammography and a histological or cytological diagnosis of benign or malignant breast disease. Patients with large or locally advanced breast cancers who had definite clinical findings where radiology was not required to make a diagnosis were excluded. The sensitivity for radiologists was non-significantly greater (81%) than surgeons (78%), but specificity and positive predictive value was identical in the two groups of readers. Combining the reports of the radiologists and surgeons increased sensitivity to 85.4% which is a significant increase in the sensitivity of the radiologist alone,P =0.02. This study indicates that symptomatic mammograms should be read by surgeons as well as radiologists.

BACKGROUND:The Edinburgh randomised trial of breast-cancer screening recruited women aged 45-64 years from 1978 to 1981 (cohort 1), and those aged 45-49 years during 1982-85 (cohorts 2 and 3). Results based on 14 years of follow-up and 270,000 woman-years of observation are reported.METHODS:Breast-cancer mortality rates in the intervention group (28,628 women offered screening) were compared with those in the control group (26,026) with adjustment for socioeconomic status (SES) of general medical practices. Rate ratios were derived by means of logistic regression for the total trial population and for women first offered screening while younger than 50 years. Analyses were by intention to treat.FINDINGS:Initial unadjusted results showed a difference of just 13% in breast-cancer mortality rates between the intervention and control groups (156 deaths [5.18 per 10,000] vs 167 [6.04 per 10,000]; rate ratio 0.87 [95% CI 0.70-1.06]), but the results were influenced by differences in SES by trial group. After adjustment for SES, the rate ratio was 0.79 (95% CI 0.60-1.02). When deaths after diagnosis more than 3 years after the end of the study were censored the rate ratio became 0.71 (0.53-0.95). There was no evidence of heterogeneity by age at entry and no evidence that younger entrants had smaller or delayed benefit (rate ratio 0.70 [0.41-1.20]). No breast-cancer mortality benefit was observed for women whose breast cancers were diagnosed when they were younger than 50 years. Other-cause mortality rates did not differ by trial group when adjusted for SES.INTERPRETATION:Our findings confirm results from randomised trials in Sweden and the USA that screening for breast cancer lowers breast-cancer mortality. Similar results are reported by the UK geographical comparison, UK Trial of Early Detection of Breast Cancer. The results for younger women suggest benefit from introduction of screening before 50 years of age.

The aim of this study was to assess and quantify the results of the double reading regime in the Scottish Breast Screening Programme for the years 1992–1996, and to use this information to make a recommendation as to whether this practice should be continued. This study is a retrospective data analysis of the Scottish Breast Screening Programme (part of the UK NHSBSP). Outcome data were analysed for all women attending the Scottish Breast Screening Programme from 1 April 1992 to 31 March 1996. The number of additional cancers detected by the second reader only and the number of additional women recalled by the second reader only were assessed. Double reading resulted in the detection of 259 additional cancers by the second reader in the 4-year period. This represents 10.5% of the total cancers detected in that time. The effect of double reading on the number of recalls can only be obtained for a subset of the data. Analysis of this subset showed that an additional 4616 women (27% of the total number of women recalled) were recalled to obtain 170 additional cancers (12% of total cancers). Double reading has increased the cancer detection rate of the Scottish Breast Screening Programme. Over 10% of cancers were detected only by the second reader. This improvement in sensitivity has been maintained over the 4 years reviewed. Using a second reader resulted in a 13% increase in the cancer detection rate, although this was associated with a 37% increase in recall rate. At present we find no reason to discontinue the practice of double reading, although this will be reviewed at intervals as technological advances are introduced.

A retrospective study found that a breast screening clinic generated fewer localization biopsies for non-palpable mammographic abnormalities than a symptomatic clinic (3.36 versus 9.89 per 1000 mammograms, respectively) and that a greater proportion of such biopsies were malignant. This study determined the reason for this difference. There were 108 of 304 (35.5 per cent) and 17 of 130 (13.1 per cent) carcinomas in women attending the screening and breast clinics respectively (relative risk 2.72 (95 per cent confidence interval 1.70-4.34)). This difference was regardless of age. The characteristics of the mammographic abnormality, the Wolfe pattern, a family history of breast carcinoma, parity and age at first pregnancy were similar in both groups. Women attending the screening clinic were referred for localization biopsy after assessment by clinicians and radiologists at a joint clinic; there was no joint assessment for patients attending the breast clinic. The same staff attended both clinics, although the proportion of time spent at each varied. This study suggests that all women with a non-palpable mammographic abnormality should be reviewed at a joint assessment clinic before localization biopsy is recommended.

127 women attending the Edinburgh Breast Screening Centre were found to have small clusters of microcalcifications (maximum diameter 1 cm) of a potentially malignant nature. Using criteria previously postulated, 1 they were classified into three groups: uniform localised, non-uniform widespread, and non-uniform localised, using hand-held magnification. In each group, the risk of malignancy was assessed in the short and long-term. The cancer detection rate of the uniform localised calcification, 67 women, 16 (24%) biopsied, was 0% immediately and 1.5% when a further biopsy was carried out after 2 years. For non-uniform widespread calcification, the cancer detection rate, 49 women, 31 (63%) biopsied, was 6 (12%) immediately and 8 (16%) when a further 3 biopsies were carried out up to 2 years later. The cancer detection rate of non-uniform localised calcifications, 11 women, all biopsied, was 7 (64%). The use of this classification of microcalcification provided a significant predictor for identification of breast cancer (p<0.001). Conventional risk factors were also examined, but none markedly improved discrimination with only family history approaching statistical significance (p = 0.09). The utility of the method in the screening situation is discussed.

In the Edinburgh Randomised Breast Screening Project (EBSP) to December 1988 there were 500 cancers in the study population invited to screening and 340 cancers identified in the control population. The size and negative lymph node status characteristics of invasive cancers from the two populations were significantly different (P less than 0.05). The cancers detected by screening were predominantly 'early stage', with 16% noninvasive (PTIS) and 42% invasive stage I (pT1 node negative), whereas cancers were frequently 'late stage' (more than pT2) and inoperable in nonattenders (44%) and controls (36%). Grouped according to customary size ranges of invasive cancers, the proportion of cases lymph node positive differed in those screen detected compared with controls, but the benefit in favour of screen detection was not constant. In comparisons of cancers detected at prevalence and incidence screens, as a test of conformity with screening theory, no significant differences were apparent according to size and lymph node status, yet the characteristics of histological type of cancer discriminated significantly (P less than 0.05). When these same histological characteristics were used to compare survival, the capacity to separate invasive cancers into two groups having good and poor survival probabilities was evident, with a significant improvement for the screen detected poor survival group compared with controls (P less than 0.05).

Six thousand and eighty women aged 40 to 64 years were screened for breast cancer by single oblique view mammography and 908 (14.9 per cent) were recalled for further examinations. It was estimated that the use of two-view mammography for initial screening would have resulted in a fall of the number of women recalled to 581 (9.5 per cent). More recently, with better equipment and the routine use of a moving grid, the recall rate at initial singleview screening in women over the age of 50 has fallen to the region of 10 per cent. The place of two-view screening is being evaluated in conjunction with grid films and, should a similar proportional fall in recall rates be gained by the addition of a second view, there may well be a place for two-view screening in this situation too.

Four hundred and ninety-three women underwent 515 localization biopsies for non-palpable mammographic abnormalities. The mammographic abnormality was located with a hooked wire in 509 cases. Specimen radiology was performed on all excised tissue. The mammographic abnormality was visualized in the first piece of tissue excised in 402 (78.1 per cent) cases and complete excision was achieved in 476 (92.4 per cent). A palpable nodule was removed in 38 (7.4 per cent) cases and in 17 (44.7 per cent) was shown to contain a carcinoma. The mammographic abnormality was missed in 14 (2.7 per cent) cases or only partly excised in 13 (2.5 per cent). Overall 144 (28.0 per cent) localization biopsies were malignant. The mammographic abnormality was not visualized on the specimen radiograph more frequently in women aged under 55 years, in women with dense breast (Wolfe grade DM or DY) or in those whose mammographic abnormality contained only microcalcification. The 27 women in whom the mammographic abnormality was not visible on the specimen radiograph underwent repeat mammography 2 months later. Only two women required a further localization biopsy and the mammographic abnormality was recovered in the first piece of tissue excised. Women with a carcinoma underwent mastectomy or wide local excision, and residual carcinoma at the localization biopsy site was found in 64 (44.4 per cent) cases. Oestrogen receptor analysis by ligand binding assay was possible in only 71 (49.3 per cent) carcinomas. If the specimen radiograph does not show the mammographic abnormality within pieces of tissue excised and there is no palpable nodule it may be best to conclude the biopsy. In this series these missed lesions were usually benign. Only rarely is a second localization biopsy required and this is performed without difficulty.

As part of a programme of assessment of the 'Sterotix' localisation device, aspiration cytology was carried out on 50 patients with 52 impalpable, mammographically detected breast lesions using the stereotaxic guidance device. This was followed by an open localisation biopsy of the area for confirmation. In 12 patients (23%) the aspirations failed to yield sufficient material for diagnosis. This was frequently due to the poorly cellular nature or very small size of the lesions. Of the remaining 40 patients, 15 were regarded as having both mammographically and cytologically benign changes which were confirmed histologically; they could thus have been spared diagnostic surgery. Ten patients had a diagnosis of malignancy with both investigations, and could have had planned investigation and subsequent definitive surgery. Of the remainder, 14 lesions had a report of malignancy or suspicion of it with either technique and these patients would have come to conventional localisation biopsy. Only one patient was found to have a malignancy, who had cytologically benign and mammographically 'probably benign' disease: this was an invasive lobular carcinoma with a dominant in-situ component and may well have been an incidental finding on biopsy.

Edinburgh was selected as one of the centres in the UK Seven-year Trial of Breast Screening of women aged 45-65 which began in 1979. Subsequently, our study was extended to a randomised trial with its own control population within the city. Half the practices were randomly allocated for screening, giving a cluster sampling of women. The total number in the trial is 65,000. Women with previously diagnosed breast cancer are excluded. Women allocated for screening are invited to the clinic and screened according to the procedures specified in the U.K. protocol, having clinical examination every year and mammography on alternate years. The two modalities of screening are assessed independently and the role of nurses is being evaluated. Breast cancer incidence is monitored by pathology register and the local cancer registry office and deaths from the General Register office. Long-term follow-up will be obtained through flagging at NHS Central Register. To determine the value of screening, standard statistical methods will be used to compare breast cancer mortality rates in the whole of the screening population with that of the controls. This trial has a power of 83% of detecting a reduction in mortality of 35% after 7 years of follow-up and a power of 95% of detecting a similar reduction at 10 years (alpha = 0.05, one-sided test).

Single oblique-view mammography has been recommended for screening purposes. The authors present data indicating that using the oblique view only can allow 11% of cancers to remain undetected. The smallest and potentially curable cancers are most likely to be overlooked in this way; any possible benefit of screening is thereby reduced. Data are also presented to show that 39% of women may require other views, for reasons not necessarily related to cancer detection. It is therefore recommended that all women have four-view mammography (oblique plus craniocaudal views of each breast) at their first screening visit.

Between 1976 and 1982, 190 non-palpable mammographic abnormalities considered to be suspicious of malignancy were excised using a needle localization technique. The indications for biopsy, technique for localization, method for confirmation of excision and histopathological preparation are presented. The histopathological diagnosis of these lesions were 150 benign and 40 malignant. There was no clear correlation between the mammographic appearances and the occurrence of cancer. Compared with 100 consecutive women with palpable breast cancer the impalpable and mammographically detected tumours were smaller, more often non-invasive and associated with negative axillary nodes.

The mammograms and specimen radiographs of 45 women in whom the presence of microcalcification played a major part in the decision to biopsy, were studied to determine possible distinguishing features. A mammographic lesion of 150 mm2 or less with an irregular density and five or more calcific particles, especially if palpable, was very likely to be an invasive carcinoma. With improved resolution, it should become possible to distinguish those calcifications covering 150 mm2 or less in the mammograms which are associated with parenchymal structures and those that are associated with stromal elements. Features that may potentially distinguish some benign parenchymal calcifications and those parenchymal calcifications associated with non-invasive malignancy are described. There will probably remain a few benign parenchymal associated calcifications which are identical to the calcifications associated with non-invasive cancer. Implications for improvement in technique are considered.

Nineteen localization biopsies were performed on eighteen women, where routine mammography revealed impalpable abnormalities. These abnormalities are described and the results of biopsy given. Six carcinomas were detected, all of which were shown to have no evidence of metastatic disease.

A new apparatus for ‘fluorodensitometry’ of the lung is briefly described. The apparatus differs from conventional techniques by employing a small source of gamma radiation (Caesium 137) in place of X-Rays. Ventilatory and circulatory studies in normal subjects, and circulatory studies in a case of pulmonary embolism are presented. A new apparatus for ‘fluorodensitometry’ of the lung is briefly described. The apparatus differs from conventional techniques by employing a small source of gamma radiation (Caesium 137) in place of X-Rays. Ventilatory and circulatory studies in normal subjects, and circulatory studies in a case of pulmonary embolism are presented.