Mammographic density and the risk of breast cancer recurrence after breast-conserving surgery.

Background: Women with invasive breast cancer who are treated with breast-conserving surgery and radiotherapy face a cumulative risk of local disease recurrence of approximately 10% at 10 years. To the authors' knowledge, the role of mammographic density as a risk factor for the development of local recurrence has not been thoroughly evaluated to date.

Methods: Medical records were reviewed for 335 patients who underwent breast-conserving surgery for invasive breast cancer and for whom a pretreatment mammogram was available.

Mammographic density and the risk and detection of breast cancer.

Background: Extensive mammographic density is associated with an increased risk of breast cancer and makes the detection of cancer by mammography difficult, but the influence of density on risk according to method of cancer detection is unknown.

Methods: We carried out three nested case-control studies in screened populations with 1112 matched case-control pairs. We examined the association of the measured percentage of density in the baseline mammogram with risk of breast cancer, according to method of cancer detection, time since the initiation of screening, and age.

Influence of patterns of hormone replacement therapy use and mammographic density on breast cancer detection.

Background: There is evidence that factors such as current hormone replacement therapy (HRT) use and mammographic density may each lower the sensitivity of mammography and are associated with a greater risk of developing an interval cancer. This study explores this relationship further by examining the influence of patterns of HRT use and the percentage of mammographic density on the detection of breast cancer by classification of interval cancer.

Methods: This study uses a case-case design nested within a cohort of women screened by the Ontario Breast Screening Program between 1994 and 2002.

Risk factors for breast cancer associated with mammographic features in Singaporean chinese women.

Background: Mammographic density has been found to be a strong risk factor for breast cancer and to be associated with age, body weight, parity, and menopausal status. Most studies to date have been carried out in Western populations. The purpose of the study described here was to determine in a cross-sectional study in a Singaporean Chinese population the demographic, menstrual, reproductive, and anthropometric factors that are associated with quantitative variations in age-adjusted percentage mammographic densities and to examine the association of these factors with the dense and nondense areas of the mammogram.

The association of breast mitogens with mammographic densities.

Radiologically dense breast tissue (mammographic density) is strongly associated with risk of breast cancer, but the biological basis for this association is unknown. In this study we have examined the association of circulating levels of hormones and growth factors with mammographic density. A total of 382 subjects, 193 premenopausal and 189 postmenopausal, without previous breast cancer or current hormone use, were selected in each of five categories of breast density from mammography units.

In situ duct carcinoma of the breast: clinical and histopathologic factors and association with recurrent carcinoma.

There has been a recent increase in the diagnosis of in situ duct carcinoma of the breast (DCIS) as a result of mammographic screening. DCIS is heterogeneous in appearance and likely in prognosis. There is no generally accepted model to predict progression to invasive carcinoma.

Growth factors and stromal matrix proteins associated with mammographic densities.

Extensive radiologically dense breast tissue is associated with a marked increase in breast cancer risk. To explore the biological basis for this association, we have examined the association of growth factors and stromal matrix proteins in breast tissue with mammographic densities. Ninety-two formalin-fixed paraffin blocks of breast tissues surrounding benign lesions were obtained, half from breasts with little or no density and half from breasts with extensive density, matched for age at biopsy.

Breast cancer risk and measured mammographic density.

It has been well established that there is a positive correlation between the dense appearance of breast stroma and parenchyma on a mammogram and the risk of breast cancer. Subjective assessment by radiologists indicated relative risks on the order of 4 to 6 for the group of women whose mammograms showed a density of over 75% or more of the projected area compared to those with an absence of density. In order to obtain a more quantitative, continuous and reproducible means of estimating breast density, which is sensitive to small changes, we have developed quantitative methods for the analysis of mammographic density, which can be applied to digitized mammograms.

Mammographic densities and risk of breast cancer among subjects with a family history of this disease.

Background: A family history of breast cancer is known to increase risk of the disease, but other genetic and environmental factors that modify this risk are likely to exist. One of these factors is mammographic density, and we have sought evidence that it is associated with increased risk of breast cancer among women with a family history of breast cancer.

Methods: We used data from a nested case-control study based on the Canadian National Breast Screening Study (NBSS).

Assessment of treatment for patients with primary ductal carcinoma in situ in the breast.

Background: Current mammographic technology has resulted in increased detection of ductal carcinoma in situ (DCIS). It is necessary to assess which patients presenting with DCIS are good candidates for breast conservation and which of these patients should receive adjuvant radiation.

Methods: We accrued clinical data for 124 patients with a primary diagnosis of DCIS from 1979 through 1994.

Symmetry of projection in the quantitative analysis of mammographic images.

Mammographic parenchymal patterns are among the strongest indicators of the risk of developing breast cancer. Risk evaluation through breast patterns may have an important role in studies of the aetiology of breast cancer and for monitoring changes in the breast in evaluating potential risk-modifying interventions. Typically, patterns are assessed by an experienced radiologist according to Wolfe grade, or on a coarse quantitative scale according to percent density.

Mammographic signs of potential relevance to breast cancer risk: the agreement of radiologists' classification.

We have assessed the agreement of radiologists who quantitatively estimated the extent of various mammographic features of the breast. These features are of potential relevance to the estimation of the future risk of developing breast cancer. After preparation, in which various mammographic appearances and their classification were discussed and agreed upon, two radiologists, experienced in mammography, independently estimated the extent of various types of radiological density in 120 sets of mammograms, each comprised of two mediolateral and two craniocaudal views.

Combined fine-needle aspiration, physical examination and mammography in the diagnosis of palpable breast masses: their relation to outcome for women with primary breast cancer.

Objective: To examine the combined and individual predictive values of fine-needle aspiration (FNA), physical examination (PE) of the breast and mammography (the "triple test") in diagnosing breast cancer in relation to the results of open surgical biopsy.

Design: A study of the records of patients who received both FNA and open surgical biopsy for the same palpable breast lump. The results of diagnostic assessment and open surgical biopsy were categorized as positive or negative.

Magnetic resonance imaging in potential postsurgical recurrence of breast cancer: pitfalls and limitations.

Objective: To determine the sensitivity and specificity of magnetic resonance imaging (MRI) of the breast for detecting recurrent carcinoma.

Patients And Methods: Thirteen patients ranging in age from 47 to 77 years who had undergone lumpectomy 5 months to 8 years earlier and who had mammographic findings suggestive of recurrence underwent contrast-enhanced dynamic MRI. Histologic confirmation was obtained in all cases.

Automated analysis of mammographic densities.

Information derived from mammographic parenchymal patterns provides one of the strongest indicators of the risk of developing breast cancer. To address several limitations of subjective classification of mammographic parenchyma into coarse density categories, we have been investigating more quantitative, objective methods of analysing the film-screen mammogram. These include measures of the skewness of the image brightness histogram, and of image texture characterized by the fractal dimension.

Mammographic densities as a criterion for entry to a clinical trial of breast cancer prevention.

The most convincing evidence that a factor such as dietary fat is causally related to breast cancer would be obtained from a randomised controlled trial in which exposure to dietary fat intake was systematically varied. A limitation of randomised controlled trials of breast cancer prevention, however, is the large sample size required to detect plausible reductions in risk resulting from the intervention. We describe here experience over a period of 9 years with the use of one risk factor for breast cancer as a criterion for entry to a clinical trial of breast cancer prevention.

Quantitative classification of mammographic densities and breast cancer risk: results from the Canadian National Breast Screening Study.

Background: The radiographic appearance of the female breast varies from woman to woman depending on the relative amounts of fat and connective and epithelial tissues present. Variations in the mammographic density of breast tissue are referred to as the parenchymal pattern of the breast. Fat is radiologically translucent or clear (darker appearance), and both connective and epithelial tissues are radiologically dense (lighter appearance).

The quantitative analysis of mammographic densities.

Quantitative classification of mammographic parenchyma based on radiological assessment has been shown to provide one of the strongest estimates of the risk of developing breast cancer. Existing classification schemes, however, are limited by coarse category scales. In addition, subjectivity can lead to sizeable interobserver and intraobserver variations.

Evaluation of mammographic image quality: pilot study comparing five methods.

A radiograph is considered of high quality when it allows a radiologist to identify abnormalities with high sensitivity and specificity. Although many methods for assessing image quality have been devised, it is not clear which is most meaningful or how well these methods correlate with one another. A pilot study was undertaken to compare five methods of evaluating mammographic image quality.

Case-control study of factors associated with failure to detect breast cancer by mammography.

Background: Although mammography is widely used to detect breast cancer, it is recognized that not all cancers can be seen on mammographic images.

Purpose: Our purpose was to examine factors associated with failure to detect breast cancer by mammography.

Methods: A case-control study was carried out in which subjects in whom histologically verified breast cancer was not detected by mammography (false negatives) were contrasted with subjects in whom breast cancer had been detected by mammography (true positives).

Clinical performance of a cone/annular array ultrasound breast scanner.

Ultrasound is a useful adjunctive imaging modality to x-ray mammography for the detection and management of breast disease. A high resolution (0.3 mm at -6 dB) transducer consisting of co-axially aligned cone and annular array transducers has been incorporated into a prototype breast imaging system.

Plasma lipids in premenopausal women with mammographic dysplasia.

Epidemiological evidence indicates that mammographic dysplasia is associated with an increased risk of breast cancer, particularly in premenopausal women. To examine biochemical associations with mammographic dysplasia we have compared premenopausal women with different patterns of the breast parenchyma on mammography. One group had extensive radiological dysplasia (n = 30) and the other no dysplasia (n = 16).

Clinical trial of low-fat, high-carbohydrate diet in subjects with mammographic dysplasia: report of early outcomes.

Despite evidence that dietary fat intake may influence breast cancer risk, there is little information about the effects of dietary fat on the human breast. We have studied the effects of dietary fat on the breast by examining the influence of dietary fat reduction on mammographic dysplasia (nodular or sheetlike areas of radiological density). Subjects with mammographic dysplasia were randomly allocated to a control group, in which they received advice about maintaining a balanced diet (36% of calories as fat), or an intervention group, in which they were taught to reduce dietary fat to a target of 15% of calories.

Ultrasonographically defined parenchymal patterns of the breast: relationship to mammographic patterns and other risk factors for breast cancer.

We have used ultrasound of the breast to define four parenchymal patterns in which increasing proportions of the breast are replaced by densely echogenic tissue. A series of 452 symptomatic women examined by both ultrasound and conventional X-ray mammography was reviewed to determine whether these ultrasonographic images could predict the breast parenchymal pattern defined mammographically. A very strong correlation was demonstrated between the breast pattern on ultrasound and the volume of the breast replaced by either dysplasia (Kendall's tau-b = 0.

Age as a confounding factor in the association of mammographic dysplasia and estrogen receptor concentration in breast cancer.

We have examined the association between hormone receptor concentration in primary breast cancer and the mammographic pattern of the breast in which the cancer arose. A significant association was found between the concentration of estrogen receptor and the proportion of the breast volume occupied by the radiological signs of dysplasia. Both estrogen receptor concentration and dysplasia were found to be strongly associated with age.