Screening with magnetic resonance imaging and mammography of a UK population at high familial risk of breast cancer: a prospective multicentre cohort study (MARIBS).

BACKGROUND: Women genetically predisposed to breast cancer often develop the disease at a young age when dense breast tissue reduces the sensitivity of X-ray mammography. Our aim was, therefore, to compare contrast enhanced magnetic resonance imaging (CE MRI) with mammography for screening. METHODS: We did a prospective multicentre cohort study in 649 women aged 35-49 years with a strong family history of breast cancer or a high probability of a BRCA1, BRCA2, or TP53 mutation. We recruited participants from 22 centres in the UK, and offered the women annual screening with CE MRI and mammography for 2-7 years. FINDINGS: We diagnosed 35 cancers in the 649 women screened with both mammography and CE MRI (1881 screens): 19 by CE MRI only, six by mammography only, and eight by both, with two interval cases. Sensitivity was significantly higher for CE MRI (77%, 95% CI 60-90) than for mammography (40%, 24-58; p=0.01), and was 94% (81-99) when both methods were used. Specificity was 93% (92-95) for mammography, 81% (80-83) for CE MRI (p<0.0001), and 77% (75-79) with both methods. The difference between CE MRI and mammography sensitivities was particularly pronounced in BRCA1 carriers (13 cancers; 92%vs 23%, p=0.004). INTERPRETATION: Our findings indicate that CE MRI is more sensitive than mammography for cancer detection. Specificity for both procedures was acceptable. Despite a high proportion of grade 3 cancers, tumours were small and few women were node positive. Annual screening, combining CE MRI and mammography, would detect most tumours in this risk group.

Screening by mammography, women with a family history of breast cancer.

The aim of this study was to describe the experience of screening women under the age of 50 years with a family history of breast cancer. 1259 women attended the Family History Clinic in Manchester for their first and subsequent consultations between 30 September 1992 and 30 April 1997. All women were under the age of 50 years at the initial consultation and had a lifetime risk of breast cancer of 1 in 6 or greater. Seven prevalent, seven incident and two interval cancers were detected. The number of invasive cancers expected to occur if this high risk population had not been screened was 8.45 (in 2722 person years at risk). 12 invasive cancers were detected, giving a ratio of 1.42 (95% confidence interval 0.73-2.48). The overall cancer detection rates in this young, at risk population were similar to those in older women in the National Health Service Breast Screening Programme. The number of cancers detected in the study was greater than expected in this population. As the numbers were small, a national trial needs to be undertaken to confirm these results and to determine the long term effects of screening.

Model-based detection of spiculated lesions in mammograms.

Computer-aided mammographic prompting systems require the reliable detection of a variety of signs of cancer. In this paper we concentrate on the detection of spiculated lesions in mammograms. A spiculated lesion is typically characterized by an abnormal pattern of linear structures and a central mass. Statistical models have been developed to describe and detect both these aspects of spiculated lesions. We describe a generic method of representing patterns of linear structures, which relies on the use of factor analysis to separate the systematic and random aspects of a class of patterns. We model the appearance of central masses using local scale-orientation signatures based on recursive median filtering, approximated using principal-component analysis. For lesions of 16 mm and larger the pattern detection technique results in a sensitivity of 80% at 0.014 false positives per image, whilst the mass detection approach results in a sensitivity 80% at 0.23 false positives per image. Simple combination techniques result in an improved sensitivity and specificity close to that required to improve the performance of a radiologist in a prompting environment.

Is the three year breast screening interval too long? Occurrence of interval cancers in NHS breast screening programme's north western region.

OBJECTIVE: To report the detection rate of interval cancers in women screened by the NHS breast screening programme. DESIGN: Detection of interval cancers by computer linkage of records held by the screening centres in the North Western Regional Health Authority with breast cancer registrations at the regional cancer registry. SETTING: North Western Regional Health Authority. SUBJECTS: 137,421 women screened between 1 March 1988 and 31 March 1992 who had a negative screening result. RESULTS: 297 invasive interval cancers were detected. The rate of detection of interval cancers expressed as a proportion of the underlying incidence was 31% in the first 12 months after screening, 52% between 12 and 24 months, and 82% between 24 and 36 months. CONCLUSION: The incidence of interval cancers in the third year after breast screening approaches that which would have been expected in the absence of screening and suggests that the three year interval between screens is too long.

Response by women aged 65-79 to invitation for screening for breast cancer by mammography: a pilot study.

OBJECTIVE: To determine whether there is sufficient benefit to be gained by offering screening for breast cancer with mammography to women aged 65-79, who are not normally invited for screening. DESIGN: Pilot study of women eligible for screening but not for personal invitation. The results of this study were compared with the results of routinely screened younger women (aged 50-64) from the same general practice. SETTING: One group general practice in south Manchester. PATIENTS: The 631 women aged 65-79 on the practice list. A total of 42 (7%) were excluded by the general practitioner, and 22 (4%) invitation letters were returned by the post office. MAIN OUTCOME MEASURES: Response rates to invitation for screening assessed by three indices: crude population coverage ratio, crude invited population coverage ratio, and corrected invited population coverage ratio. RESULTS: 344 Patients aged 65-79 (61% of those invited, excluding those who could not be traced) were screened compared with 77% of women aged 50-64. The three response indices were higher for younger women than older: crude population coverage ratio = 66.5%, crude invited population coverage ratio = 69.3%, corrected invited population coverage ratio = 76.8% for women aged 50-64, compared with 54.5%, 58.4%, and 60.7% respectively for women aged 65-79. All four biopsies done in the older women gave positive results, giving a cancer detection rate of 11.6/1000 compared with 4.1/1000 among younger women. CONCLUSIONS: These results show that there is a potential for high attendance at routine screening by older women if they are invited in the same way as younger women. If these results are found elsewhere the costs and benefits of screening older women should be reassessed.

Computer-assisted mammographic imaging.

Computer-assisted mammography imaging comprises computer-based analysis of digitized images resulting in prompts aiding mammographic interpretation and computerized stereotactic localization devices which improve location accuracy. The commercial prompting systems available are designed to draw attention to mammographic abnormalities detected by algorithms based on symptomatic practise in North America. High sensitivity rates are important commercially but result in increased false prompt rates, which are known to distract radiologists. A national shortage of breast radiologists in the UK necessitates evaluation of such systems in a population breast screening programme to determine effectiveness in increasing cancer detection and feasibility of implementation.

Computed tomographic peritoneography in the investigation of abdominal wall and genital swelling in patients on continuous ambulatory peritoneal dialysis.

Computed tomography (CT) of the abdomen following the intraperitoneal instillation of water soluble contrast medium was employed in seven patients with lower abdominal wall and/or scrotal swelling which had developed whilst on continuous ambulatory peritoneal dialysis. In all seven patients contrast medium was seen to leak into the tissues of the anterior abdominal wall from the site of insertion of the Tenckhoff catheter, and in two male patients was shown to track into the scrotum (in one via a patent processus vaginalis). This technique gave accurate anatomical detail which was useful for planning subsequent management.

Non-invasive ultrasound localization of impalpable breast lesions.

Thirty patients presenting through the Breast Screening Programme with impalpable breast abnormalities clearly visible on ultrasound, underwent non-invasive ultrasound localization. The patient was scanned so that the ultrasound abnormality lay below the probe and the skin at this site marked with a skin marker. In all cases the abnormality was easily identified and removed at surgery. All the surgical biopsies contained either a carcinoma (17 cases) or fibroadenoma (13 cases). This non-invasive technique is a simple and accurate method for localizing small ultrasonically visible breast abnormalities.

The influence of previous films on screening mammographic interpretation and detection of breast carcinoma.

AIM: To establish if the availability of previous mammograms improves the detection rate of carcinomas and reduces supplementary examinations in the National Health Service Breast Screening Programme (NHSBSP). METHOD: Eight radiologists with varying experience but an interest in reporting mammograms reported 100 mammograms on two occasions, at least 1 month apart. In this selection of 100 mammograms we randomly inserted 12 abnormal films, with both benign and malignant changes present. These were chosen retrospectively with histological correlation of the abnormality. On the first occasion only the current films were reviewed, however, on the second occasion previous films were available for comparison. The films were viewed under standard viewing conditions, and the participants were asked to comment if they required further views or would refer the patient for either an ultrasound examination or surgical referral. RESULTS: Receiver operating curves (ROC) were constructed for the group's overall performance on each of the occasions and there was no difference in the curves. This indicates that the presence of previous films did not improve diagnostic accuracy. The presence of previous films did, however, lead to a significant reduction in the number of additional views and ultrasound examinations that would have been requested. The most significant reductions occurred in the group of normal mammograms. CONCLUSION: The presence of previous mammograms does not lead to an improvement in diagnostic accuracy. However, the presence of previous films led to significant reduction in additional examinations and ultrasound examinations.

A comparison of axillary node status between cancers detected at the prevalence and first incidence breast screening rounds.

Screen-detected breast cancers are smaller than those detected in symptomatic populations and, for any given size, they are associated with fewer lymph node metastases. The management of axillary lymph nodes in patients with screen-detected breast cancer remains controversial. We have previously reported that prevalence (initial screen)-detected cancers are associated with nodal metastases in 17.4% of cases overall. Cancers < or = 10 mm, of any grade, are associated with metastases in only 5% of cases, and grade I cancers <30 mm are not associated with metastases. This led to our recommendation that axillary surgery is unnecessary for these groups of women. The present study compared the nodal status of cancers detected at the prevalence and first incidence (second) screens in order to determine whether our recommendation is appropriate for cancers detected at the first incidence screen. Overall, 30.1% of cancers detected in the first incidence screen presented axillary nodal metastases. At all size ranges, cancers detected at the first incidence screen were associated with significantly more lymph node metastases than prevalence-detected cancers. In particular, cancers < or = 10 mm were associated with metastases in 14.3% of cases. With the possible exception of grade I cancers, we believe that surgical staging of the axilla is essential for cancers detected at the first incidence screen, irrespective of size.

Treatment of the axilla in patients with screen-detected breast cancer.

Management of the axillary lymph nodes in patients with screen-detected breast cancer is controversial. Optimal treatment should combine accurate determination of node status and avoidance of unnecessary morbidity. This study attempted to determine whether axillary node status could be accurately predicted using selected criteria in women with screen-detected breast cancer. Of 223 breast cancers excised in the Greater Manchester breast screening programme, 180 were invasive and 40 of these had associated lymph node metastases. The presence of involved nodes was associated with large tumour size, high tumour grade and the absence of mammographic microcalcification. Multiple logistic regression analysis revealed that each of these three factors was independently significant. Women with a screen-detected breast cancer < 1 cm in diameter or those with grade I tumours < 3 cm (35 per cent of the total) could be spared axillary surgery with an expected reduction in morbidity and operating time.

Breast cancer diagnosis using scattered X-rays.

Small-angle X-ray diffraction data has been collected from 99 ;core-cut' breast tissue specimens representing a number of different pathologies. Data in the range 75-1390 A have been compared with controls from patients with no breast disease. Bessel functions and Bragg maxima resulting from the fibrillar structure of collagen have been identified. The Bragg maxima indexed onto a 649 A lattice. Systematic differences in the intensities and D-spacings between the collagen of malignant, benign and normal tissue groups have been clearly demonstrated and quantified. These differences appear to be due to a significantly lower structural order within the malignant tissues. Possible explanations for this are discussed and the potential for utilizing this observation in cancer diagnosis is considered.