Adverse effects of increased body weight on quantitative measures of mammographic image quality

Mammographic features differ with body composition in women with breast cancer

OBJECTIVES

There are several breast cancer (BC) risk factors-many related to body composition, hormonal status, and fertility patterns. However, it is not known if risk factors in healthy women are associated with specific mammographic features at the time of BC diagnosis. Our aim was to assess the potential association between pre-diagnostic body composition and mammographic features in the diagnostic BC image.

MATERIALS AND METHODS

The prospective Malmö Diet and Cancer Study includes women with invasive BC from 1991 to 2014 (n = 1116). BC risk factors at baseline were registered (anthropometric measures, menopausal status, and parity) along with mammography data from BC diagnosis (breast density, mammographic tumor appearance, and mode of detection). We investigated associations between anthropometric measures and mammographic features via logistic regression analyses, yielding odds ratios (OR) with 95% confidence intervals (CI).

RESULTS

There was an association between high body mass index (BMI) (≥ 30) at baseline and spiculated tumor appearance (OR 1.370 (95% CI: 0.941-2.010)), primarily in women with clinically detected cancers (OR 2.240 (95% CI: 1.280-3.940)), and in postmenopausal women (OR 1.580 (95% CI: 1.030-2.440)). Furthermore, an inverse association between high BMI (≥ 30) and high breast density (OR 0.270 (95% CI: 0.166-0.438)) was found.

CONCLUSION

This study demonstrated an association between obesity and a spiculated mass on mammography-especially in women with clinically detected cancers and in postmenopausal women. These findings offer insights on the relationship between risk factors in healthy women and related mammographic features in subsequent BC.

CLINICAL RELEVANCE STATEMENT

With increasing numbers of both BC incidence and women with obesity, it is important to highlight mammographic findings in women with an unhealthy weight.

KEY POINTS

Women with obesity and BC may present with certain mammographic features. Spiculated masses were more common in women with obesity, especially postmenopausal women, and those with clinically detected BCs. Insights on the relationship between obesity and related mammographic features will aid mammographic interpretation.

Obesity-Associated Breast Cancer: Analysis of Risk Factors and Current Clinical Evaluation

Several studies show that a significantly stronger association is obvious between increased body mass index (BMI) and higher breast cancer incidence. Additionally, obese and postmenopausal women are at higher risk of all-cause and breast cancer-specific mortality compared with non-obese women with breast cancer. In this context, increased levels of estrogens, excessive aromatization activity of the adipose tissue, overexpression of pro-inflammatory cytokines, insulin resistance, adipocyte-derived adipokines, hypercholesterolemia, and excessive oxidative stress contribute to the development of breast cancer in obese women. Genetic evaluation is an integral part of diagnosis and treatment for patients with breast cancer. Despite trimodality therapy, the four-year cumulative incidence of regional recurrence is significantly higher. Axillary lymph nodes as well as primary lesions have diagnostic, prognostic, and therapeutic significance for the management of breast cancer. In clinical setting, because of the obese population primary lesions and enlarged lymph nodes could be less palpable, the diagnosis may be challenging due to misinterpretation of physical findings. Thereby, a nomogram has been created as the "Breast Imaging Reporting and Data System" (BI-RADS) to increase agreement and decision-making consistency between mammography and ultrasonography (USG) experts. Additionally, the "breast density classification system," "artificial intelligence risk scores," ligand-targeted receptor probes," "digital breast tomosynthesis," "diffusion-weighted imaging," "18F-fluoro-2-deoxy-D-glucose positron emission tomography," and "dynamic contrast-enhanced magnetic resonance imaging (MRI)" are important techniques for the earlier detection of breast cancers and to reduce false-positive results. A high concordance between estrogen receptor (ER) and progesterone receptor (PR) status evaluated in preoperative percutaneous core needle biopsy and surgical specimens is demonstrated. Breast cancer surgery has become increasingly conservative; however, mastectomy may be combined with any axillary procedures, such as sentinel lymph node biopsy (SLNB) and/or axillary lymph node dissection whenever is required. As a rule, SLNB-guided axillary dissection in breast cancer patients who have clinically axillary lymph node-positive to node-negative conversion following neoadjuvant chemotherapy is recommended, because lymphedema is the most debilitating complication after any axillary surgery. There is no clear consensus on the optimal treatment of occult breast cancer, which is much discussed today. Similarly, the current trend in metastatic breast cancer is that the main palliative treatment option is systemic therapy.

A review of screening mammography: The benefits and radiation risks put into perspective

INTRODUCTION/BACKGROUND

In medical imaging a benefit to risk analysis is required when justifying or implementing diagnostic procedures. Screening mammography is no exception and in particular concerns around the use of radiation to help diagnose cancer must be addressed.

METHODS

The Medline database and various established reports on breast screening and radiological protection were utilised to explore this review.

RESULTS/DISCUSSION

The benefit of screening is well argued; the ability to detect and treat breast cancer has led to a 91% 5-year survival rate and 497 deaths prevented from breast cancer amongst 100,000 screened women. Subsequently, screening guidelines by various countries recommend annual, biennial or triennial screening from ages somewhere between 40-74 years. Whilst the literature presents different perspectives on screening younger and older women, the current evidence of benefit for screening women <40 and ≥75 years is currently not strong. The radiation dose and associated risk delivered to each woman for a single examination is dependent upon age, breast density and breast thickness, however the average mean glandular dose is around 2.5-3 mGy, and this would result in 65 induced cancers and 8 deaths per 100,000 women over a screening lifetime from 40-74 years. This results in a ratio of lives saved to deaths from induced cancer of 62:1.

CONCLUSION

Therefore, compared to the potential mortality reduction achievable with screening mammography, the risk is small.

The importance of preoperative imaging methods in reduction mammoplasty

Breast reduction surgery is a common procedure in plastic surgery clinics, and there are varying practices regarding preoperative mammography and breast ultrasound in patients who have no history of cancer and no symptoms other than those caused by macromastia. In this study, we retrospectively analyzed the imaging findings of patients who presented to the plastic surgery outpatient clinic due to macromastia between January 1, 2006 and June 1, 2020 and underwent mammography and/or breast ultrasound for preoperative screening and breast magnetic resonance imaging for further examination. Patients with a history of breast cancer diagnosed prior to preoperative screening or any other breast disease were excluded. Radiologically suspicious findings were significantly more common in patients over 40 years of age and significantly less frequent in the group under 50 years of age. When the patients were grouped by the decade of life, the frequency of radiologically suspicious findings was significantly lower in the 20-29 group and significantly higher in the 40-49 and 50-59 groups. Malignancy was not detected by histopathological examination in any patient. Proliferative lesions were detected in 10 reduction mammoplasty specimens (2.4%) of 7 patients (3.1%). The correlation between radiological and histopathological findings may be weak in macromastia patients. Most suspicious radiological findings appear to be the population between 40 and 59 years of age .

A randomized controlled trial of metformin in women with components of metabolic syndrome: intervention feasibility and effects on adiposity and breast density

PURPOSE

Obesity is a known risk factor for post-menopausal breast cancer and may increase risk for triple negative breast cancer in premenopausal women. Intervention strategies are clearly needed to reduce obesity-associated breast cancer risk.

METHODS

We conducted a Phase II double-blind, randomized, placebo-controlled trial of metformin in overweight/obese premenopausal women with components of metabolic syndrome to assess the potential of metformin for primary breast cancer prevention. Eligible participants were randomized to receive metformin (850 mg BID, n = 76) or placebo (n = 75) for 12 months. Outcomes included breast density, assessed by fat/water MRI with change in percent breast density as the primary endpoint, anthropometric measures, and intervention feasibility.

RESULTS

Seventy-six percent in the metformin arm and 83% in the placebo arm (p = 0.182) completed the 12-month intervention. Adherence to study agent was high with more than 80% of participants taking ≥ 80% assigned pills. The most common adverse events reported in the metformin arm were gastrointestinal in nature and subsided over time. Compared to placebo, metformin intervention led to a significant reduction in waist circumference (p < 0.001) and waist-to-hip ratio (p = 0.019). Compared to placebo, metformin did not change percent breast density and dense breast volume but led to a numerical but not significant decrease in non-dense breast volume (p = 0.070).

CONCLUSION

We conclude that metformin intervention resulted in favorable changes in anthropometric measures of adiposity and a borderline decrease in non-dense breast volume in women with metabolic dysregulation. More research is needed to understand the impact of metformin on breast cancer risk reduction.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02028221. Registered January 7, 2014, https://clinicaltrials.gov/ct2/show/NCT02028221.

Monochromatic X-rays: The future of breast imaging

PURPOSE

To present details about the innovative and disruptive technology of monochromatic X-rays and its application to breast imaging.

METHODS

To analyze results of studies done using a prototype system for breast imaging that generates monochromatic X-rays through fluorescence emission. To assess signal-to-noise ratio (SNR) as a measure of image quality at different doses in breast phantoms of different sizes and review the comparison of parameters with a standard mammography system.

RESULTS

Monochromatic X-rays reduce the radiation dose per mammogram by a factor of 5 to 10 times. For phantom simulating thick breast (9 cm), the SNR for monochromatic system was 2.6 times higher and the dose 4.2 times lower than the respective values obtained with the conventional system within the same 5 mm × 5 mm square area of the 100% glandular step wedge. For the conventional broadband system to equal the SNR of the monochromatic system, it would require a dose of 19 mGy, 29 times higher than the dose delivered by the monochromatic system. Contrast-enhanced digital mammography with monochromatic X-rays is shown to provide a simpler and more effective technique at substantially lower radiation dose.

CONCLUSIONS

Lowering radiation dose by a factor of 5 to 10 while maintaining image quality implies a major reduction in total exposure from breast cancer screening and dramatically less risk of radiation-induced cancers in at-risk women. The high SNRs for very thick breast phantoms provide strong evidence that screening with lower breast compression is possible while maintaining image quality.

Diabetes, Obesity, and Inflammation: Impact on Clinical and Radiographic Features of Breast Cancer

Obesity, diabetes, and inflammation increase the risk of breast cancer, the most common malignancy in women. One of the mainstays of breast cancer treatment and improving outcomes is early detection through imaging-based screening. There may be a role for individualized imaging strategies for patients with certain co-morbidities. Herein, we review the literature regarding the accuracy of conventional imaging modalities in obese and diabetic women, the potential role of anti-inflammatory agents to improve detection, and the novel molecular imaging techniques that may have a role for breast cancer screening in these patients. We demonstrate that with conventional imaging modalities, increased sensitivity often comes with a loss of specificity, resulting in unnecessary biopsies and overtreatment. Obese women have body size limitations that impair image quality, and diabetes increases the risk for dense breast tis-sue. Increased density is known to obscure the diagnosis of cancer on routine screening mammography. Novel molecu-lar imaging agents with targets such as estrogen receptor, human epidermal growth factor receptor 2 (HER2), pyrimi-dine analogues, and ligand-targeted receptor probes, among others, have potential to reduce false positive results. They can also improve detection rates with increased resolution and inform therapeutic decision making. These emerg-ing imaging techniques promise to improve breast cancer diagnosis in obese patients with diabetes who have dense breasts, but more work is needed to validate their clinical application.

Association of Imaging-Based Body Fat Distribution and Mammographic Density in the Multiethnic Cohort Adiposity Phenotype Study

BACKGROUND

As the stronger association of obesity with postmenopausal breast cancer in Asian than white women may be due to body fat distribution, we examined the relation of adiposity measures with percent mammographic density (PMD), a strong predictor of breast cancer incidence.

METHODS

A total of 938 women from five ethnic groups (69.1 ± 2.7 years) in the Adiposity Phenotype Study (APS) underwent DXA and MRI imaging. PMD was assessed in routine mammograms using a computer-assisted method. Spearman correlation coefficients were computed and general linear models were applied to estimate regression coefficients (β) for PMD per 0.5 SD units of adiposity measures while adjusting for known confounders, including DXA total body fat.

RESULTS

For 701 (75%) of the participants (69.1 ± 2.7 years), valid mammograms were obtained. Whereas total body fat, the trunk-to-periphery fat ratio (TPFR), visceral fat (VAT), and subcutaneous fat (SAT) were inversely correlated with PMD (P < 0.0001), the VAT/SAT ratio correlated positively (r spearman = 0.10; P = 0.01). In fully adjusted models, PMD remained inversely related to TPFR and SAT and disappeared for VAT, while it was strengthened for VAT/SAT (β = 0.51; P = 0.009). This relation was stronger in Japanese Americans than other ethnic groups.

CONCLUSIONS

This is the first study to show an association of a high VAT/SAT ratio with greater PMD, a marker of breast cancer risk after taking into account total body fat.

IMPACT

The results indicate a link between the propensity to accumulate VAT and the amount of fat in the breast (1-PMD), which may influence the relation of obesity with breast cancer incidence.

Screening Sensitivity According to Breast Cancer Location

PURPOSE

To examine the relation between breast cancer location and screening mammogram sensitivity, and assess whether this association is modified by body mass index (BMI) or breast density.

METHODS

This study is based on all interval cancers (n = 481) and a random sample of screen-detected cancers (n = 481) diagnosed in Quebec Breast Cancer Screening Program participants in 2007. Film-screening mammograms, diagnostic mammograms, and ultrasound reports (when available) were requested for these cases. The breast cancer was then localised in mediolateral oblique (MLO) and craniocaudal (CC) projections of the breast by 1 experienced radiologist. The association between cancer location and screening sensitivity was assessed by logistic regression. Adjusted sensitivity and sensitivity ratios were obtained by marginal standardisation.

RESULTS

A total of 369 screen-detected and 268 interval cancers could be localised in MLO and/or CC projections. The 2-year sensitivity reached 68%. Overall, sensitivity was not statistically associated with location of the cancer. However, sensitivity seems lower in MLO posterior inferior area for women with BMI ≥ 25 kg/m² compared to sensitivity in central area for women with lower BMI (adjusted sensitivity ratio: 0.58, 95% confidence interval [CI]: 0.17-0.98). Lower sensitivity was also observed in subareolar areas for women with breast density ≥ 50% compared to the central areas for women with lower breast density (for MLO and CC projections, adjusted sensitivity ratio and 95% CI of, respectively, 0.54 [0.13-0.96] and 0.46 [0.01-0.93]).

CONCLUSIONS

Screening sensitivity seems lower in MLO posterior inferior area in women with higher BMI and in subareolar areas in women with higher breast density. When interpreting screening mammograms, radiologists need to pay special attention to these areas.

Technical challenges of imaging & image-guided interventions in obese patients

Obese patients challenge imaging departments in their ability to obtain diagnostic quality images and to perform image-guided interventions. These technical challenges include properly accommodating large patients on imaging equipment, adjusting equipment settings to address imaging limitations, and pre-planning and preparation for image-guided interventions to insure safe and successful outcomes. Knowing and addressing these challenges can result in successfully addressing the imaging and image-guided interventions needs of obese patients.

Mammography Clinical Image Quality and the False Positive Rate in a Canadian Breast Cancer Screening Program

PURPOSE

The study sought to determine if mammography quality is associated with the false positive (FP) rate in the Quebec breast cancer screening program in 2004 and 2005.

METHODS

Mammography quality of a random sample of screen-film mammograms was evaluated by an expert radiologist following the criteria of the Canadian Association of Radiologists. For each screening examination, scores ranging from 1 (poor quality) to 5 (excellent quality) were attributed for positioning, compression, contrast, exposure level, sharpness, and artifacts. A final overall quality score (lower or higher) was also given. Poisson regression models with robust estimation of variance and adjusted for potential confounding factors were used to assess associations of mammography quality with the FP rate.

RESULTS

Among 1,209 women without cancer, there were 104 (8.6%) FPs. Lower overall mammography quality is associated with an increase in the FP rate (risk ratio [RR], 1.4; 95% confidence interval [CI], 1.0-2.1; P = .07) but this increase was not statistically significant. Artifacts were associated with an increase in the FP rate (RR, 2.1; 95% CI, 1.3-3.3; P = .01) whereas lower quality of exposure level was related to a reduction of the FP rate (RR, 0.4; 95% CI, 0.1-1.0; P = .01). Lower quality scores for all other quality attributes were related to a nonstatistically significant increase in the FP rate of 10%-30%.

CONCLUSIONS

Artifacts can have a substantial effect on the FP rate. The effect of overall mammography quality on the FP rate may also be substantial and needs to be clarified.

Improving Performance of Mammographic Breast Positioning in an Academic Radiology Practice

OBJECTIVE

The purpose of this project was to achieve sustained improvement in mammographic breast positioning in our department.

MATERIALS AND METHODS

Between June 2013 and December 2016, we conducted a team-based performance improvement initiative with the goal of improving mammographic positioning. The team of technologists and radiologists established quantitative measures of positioning performance based on American College of Radiology (ACR) criteria, audited at least 35 mammograms per week for positioning quality, displayed performance in dashboards, provided technologists with positioning training, developed a supportive environment fostering technologist and radiologist communication surrounding mammographic positioning, and employed a mammography positioning coach to develop, improve, and maintain technologist positioning performance. Statistical significance in changes in the percentage of mammograms passing the ACR criteria were evaluated using a two-proportion z test.

RESULTS

A baseline mammogram audit performed in June 2013 showed that 67% (82/122) met ACR passing criteria for positioning. Performance improved to 80% (588/739; p < 0.01) after positioning training and technologist and radiologist agreement on positioning criteria. With individual technologist feedback, positioning further improved, with 91% of mammograms passing ACR criteria (p < 0.01). Seven months later, performance temporarily decreased to 80% but improved to 89% with implementation of a positioning coach. The overall mean performance of 91% has been sustained for 23 months. The program cost approximately $30,000 to develop, $42,000 to launch, and $25,000 per year to maintain. Almost all costs were related to personnel time.

CONCLUSION

Dedicated performance improvement methods may achieve significant and sustained improvement in mammographic breast positioning, which may better enable facilities to pass the recently instated Enhancing Quality Using the Inspection Program portion of a practice's annual Mammography Quality Standards Act inspections.

Clinical image quality in daily practice of breast cancer mammography screening

OBJECTIVE

To assess the quality of screening mammograms performed in daily practice in the Quebec Breast Cancer Screening Program.

SUBJECTS AND METHODS

Clinical image quality of a random subsample of 197 screening mammograms performed in 2004-2005 was independently evaluated by 2 radiologists based on the criteria by Canadian Association of Radiologists (CAR). When disagreement occurred for overall judgement or positioning score, the mammograms were reviewed by a third radiologist. Cohen's kappas for interrater agreement were computed. Multivariable robust Poisson regression models were used to study associations of overall quality and positioning with body mass index (BMI) and breast density.

RESULTS

The CAR criteria were not satisfied for 49.7% of the mammograms. Positioning was the quality attribute most often deficient, with 37.2% of mammograms failing positioning. Interrater agreement ranged from slight (kappa = 0.02 for compression and sharpness) to fair (kappa = 0.30 for exposure). For overall quality, women with a BMI ≥ 30 kg/m(2) had a failure proportion of 67.5% compared with 34.9% for women with a BMI<25 kg/m(2) (risk ratio 2.1 [95% confidence interval, 1.5-3.0]). For positioning, women with a BMI ≥ 30 kg/m(2) had a failure proportion of 53.8% compared with 27.9% for women with a BMI < 25 kg/m(2) (risk ratio 1.9 [95% confidence interval, 1.2-3.1]). Effects of breast density on image quality differed among radiologists.

CONCLUSION

Despite measures to ensure high-quality imaging, including CAR accreditation, approximately half of this random sample of screening mammograms failed the CAR quality standards. It would be important to define quality targets for screening mammograms carried out in daily practice to interpret such observations.

Features of cancer management in obese patients

There is worldwide increased in obesity prevalence and statistical almost half of United-States, including children, could be obese by 2050. Obesity in cancer patients is a major issue in oncology because weight gain and obesity account for approximately 20% of all cancer cases. Indeed, increased obesity is linked with higher risk of various types of cancer and a poorer survival. Although biological mechanisms underlying how obesity causes an increased risk of cancer are suggested, overweight as a putative direct cause of death is still debated. Numerous confounding factors may impact on survival, including comorbidities and imaging limitations. Moreover, difficulties to achieve the standard oncologic care with surgery, chemotherapy and/or radiation may also be concerned. Herein, we examined the specific features and potential adaptation of the cancer management in overweighed patients. Then, we reviewed how implicated molecular pathways may provide new strategies to decrease cancer risk and predict toxicities in an increasingly obese population.

Mammographic density and risk of breast cancer by adiposity: an analysis of four case-control studies

The association of mammographic breast density with breast cancer risk may vary by adiposity. To examine effect modification by body mass index (BMI), the authors standardized mammographic density data from four case-control studies (1994-2002) conducted in California, Hawaii and Minnesota and Gifu, Japan. The 1,699 cases and 2,422 controls included 45% Caucasians, 40% Asians and 9% African-Americans. Using ethnic-specific BMI cut points, 34% were classified as overweight and 19% as obese. A single reader assessed density from mammographic images using a computer-assisted method. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI) while adjusting for potential confounders. Modest heterogeneity in the relation between percent density and breast cancer risk across studies was observed (p(heterogeneity) = 0.08). Cases had a greater age-adjusted mean percent density than controls: 31.7% versus 28.5%, respectively (p <0.001). Relative to <20 percent density, the ORs for >35 were similar across BMI groups whereas the OR for 20-35 was slightly higher in overweight (OR = 1.69, 95% CI: 1.28, 2.24) and obese (OR = 1.62, 95% CI: 1.12, 2.33) than in normal weight women (OR = 1.49, 95% CI: 1.11, 2.01). Furthermore, limited evidence of effect modification by BMI of the OR per 10% increase in percent density (p(interaction) = 0.06) was observed, including subgroup analyses by menopausal status and in analyses that excluded women at the extremes of the BMI scale. Our findings indicate little, if any, modification by BMI of the effects of breast density on breast cancer risk.

Breast imaging and intervention in the overweight and obese patient

OBJECTIVE

This article comments on the challenges and coping mechanisms for evaluating overweight and obese patients with breast imaging and diagnostic techniques. With the prevalence of obesity in society, the obstacles that arise regarding patients' adherence to screening guidelines are important to address.

CONCLUSION

This article discusses social factors and physical limitations that influence these patients' desires and ability to seek health care, specifically breast care and the problems that arise during imaging and interventional procedures.

Impact of Obesity on Radiology

Obesity is impacting radiology departments throughout the country. Increasingly, the ability to acquire and interpret images is compromised by a patient's body habitus. This article provides radiologists with background information about obesity including the definition of obesity, the prevalence of obesity, and the health and economic implications; describes current problems and provides specific solutions related to imaging obese patients using various modalities; and discusses the future of medical imaging and obesity.

Impact of obesity on medical imaging and image-guided intervention

OBJECTIVE

The purpose of this article is to discuss the impact of obesity on medical imaging and provide some solutions that are currently available to tackle the challenges of imaging obese patients.

CONCLUSION

Increasingly, radiologists are asked to image morbidly obese patients. The challenges facing radiology departments include difficulties in transporting patients to the department, inability to accommodate large patients on currently designed imaging equipment, and difficulties in acquiring desired image quality.

Challenges of laparoscopic colectomy in the obese patient: a review

BACKGROUND

Perioperative care of clinically severely obese patients presents numerous unique challenges. These patients have distinctive issues with regard to cardiovascular, pulmonary, and thromboembolic complications. In addition, hospital equipment must be able to accommodate the body habitus of this population.

METHODS

A Medline search using the terms "morbid obesity," "colon resection," "obesity comorbidities," "laparoscopic colectomy," "perioperative challenges," and "risk factors" was performed for English-language articles. Further references were obtained through cross-referencing the bibliography cited in each publication.

RESULTS

The authors discussed the most relevant challenges surgeons encounter in the perioperative setting when treating obese patients.

COMMENTS

The management of the morbidly obese patient requires meticulous preoperative, intraoperative, and postoperative care. Colorectal surgeons should be familiar with obesity-related problems when treating colorectal disease processes in this patient population. The associated comorbid illnesses in this population, as well as the technical difficulties regularly posed by them, make laparoscopic colectomy a more challenging procedure than normally encountered in the nonobese patient population.

The association between obesity and screening mammography accuracy

BACKGROUND

Obesity is increasing among American women, especially as they age. The influence of obesity on the accuracy of screening mammography has not been studied extensively.

METHODS

We analyzed 100 622 screening mammography examinations performed on members of a nonprofit health plan. The relationship between body mass index (weight in kilograms divided by the square of height in meters) and measures of screening accuracy was assessed. Body mass index was categorized as underweight or normal weight (<25), overweight (25-29), obesity class I (30-34), and obesity classes II to III (> or =35).

RESULTS

Compared with underweight or normal weight women, overweight and obese women were more likely to be recalled for additional tests after adjusting for important covariates, including age and breast density (overweight odds ratio [OR], 1.17; 95% confidence interval [CI], 1.11-1.23); obesity class I OR, 1.27; 95% CI, 1.19-1.35; obesity classes II-III OR, 1.31; 95% CI, 1.22-1.41). As body mass index increased, women were more likely to have lower specificity (overweight OR, 0.86; 95% CI, 0.81-0.90; obesity class I OR, 0.79; 95% CI, 0.74-0.84; and obesity classes II-III OR, 0.77; 95% CI, 0.71-0.82). No statistically significant differences were noted in sensitivity. Adjusted receiver operating characteristic analysis showed statistically significant improvement in the area under the curve (AUC) for underweight or normal weight women (AUC = 0.941) vs overweight women (AUC = 0.916, P =.02) and underweight or normal weight women vs obesity classes II and III women (AUC = 0.904, P =.02).

CONCLUSIONS

Obese women had more than a 20% increased risk of having false-positive mammography results compared with underweight and normal weight women, although sensitivity was unchanged. Achieving a normal weight may improve screening mammography performance.

Obesity and breast cancer screening

BACKGROUND

Compared to normal weight women, women with obesity have higher mortality from breast cancer but are less often screened.

OBJECTIVES

To examine the relation between mammography use and weight category and to examine the influence of race, illness burden, and other factors on this relationship.

DESIGN AND SETTING

The 1998 National Health Interview Survey, a U.S. civilian population-based survey.

PARTICIPANTS

Five thousand, two hundred, and seventy-seven women ages 50 to 75 years who responded to the Sample Adult and Prevention questionnaires.

MEASUREMENTS

Mammogram use in the preceding 2 years.

RESULTS

Among 5277 eligible women, 72% reported mammography use. The rate was 74% among white women and 70% among black women. Among white women, mammogram use was lowest in women with a body mass index (BMI) greater than 35 kg/m(2) (64% to 67%). After adjusting for sociodemographic factors, health care access, medical conditions, hospitalizations, and mobility status, higher BMI was associated with lower screening among white women, P =.02 for trend; the relative risk (RR) for screening in moderately obese white women (BMI, 35 to 40 kg/m(2)) was 0.83 (95% confidence interval [CI], 0.68 to 0.96) compared to normal weight white women. Compared to normal weight black women, mammography use was similar or higher in overweight (BMI, 25 to 30 kg/m(2); RR, 1.19; 95% CI, 1.01 to 1.32), mildly obese (BMI, 30 to 35 kg/m(2); RR, 1.22; 95% CI, 0.98 to 1.39), and moderately obese black women (RR, 1.37; 95% CI, 1.37 to 1.50) after adjustment. The P value for the race-BMI interaction was.001. Results for white and black women were unchanged after additional adjustment for psychological functioning and health habits.

CONCLUSION

Among white women, those with higher BMI were less likely to undergo breast cancer screening than normal weight women. This relationship was not seen in black women. Our findings were not explained by differences in sociodemographic factors, health care access, illness burden, or health habits. More research is needed to determine the reasons for these disparities so that appropriate efforts can be made to improve screening.

Breast cancer size in postmenopausal women is correlated with body mass index and androgen serum levels

Our objective was to investigate the effects of age, weight, body mass index (BMI), sex steroid receptor status and serum parameters such as estradiol, testosterone, androstenedione, dehydroepiandrosterone sulfate (DHEAS) and leptin on the size of a malignant breast tumor. A total of 62 premenopausal (median age 44.0 years) and 151 postmenopausal (median age 59.1 years) Caucasian women undergoing lumpectomy or mastectomy for invasive breast cancer were examined. Patient parameters (age, body weight, BMI), tumor parameters (tumor size, estrogen and progesterone receptor status) and serum parameters (estradiol, testosterone, androstenedione, DHEAS and leptin) were measured. An increase of BMI and DHEAS levels was associated with larger tumors by partial correlation (rp) analysis (rp = 0.418, p = 0.008; and rp = 0.329, p = 0.041, respectively), whereas higher androstenedione levels corresponded with smaller tumors. Furthermore, BMI, androstenedione and DHEAS levels were correlated: an increase in DHEAS was associated with higher androstenedione serum concentrations (rp = 0.603, p < 0.001), but was also associated with a lower BMI (rp = -0.378, p < 0.001). BMI and androstenedione serum concentrations were also associated (rp = 0.242, p = 0.009), thus closing a circle of mutual interactions. We conclude that, although breast cancer progression is characterized by autonomous growth that has become independent of growth regulatory mechanisms, tumor size at the time of detection is influenced by a complex system of counter-regulatory feedback mechanisms that might represent the body's physiological attempt to control the size of a malignant tumor.

Computer-based collection of mammographic exposure data for quality assurance and dosimetry

PURPOSE

There is potentially more to quality assurance in mammography than the MQSA mandated tests. In this paper we describe a method of capturing individual mammogram technical parameters and the creation of new measures. These include the numbers of images required for each screening examination by technologist, median compression by technologist, and the radiation dose of the examination to the general population of patients.

METHOD/MATERIALS

With this method we describe a semiautomated method of the collection of technical data from mammography exposures. The data that are automatically created by the mammography unit are saved on a computer for later analysis. The method was used on 2738 consecutive screening mammography examinations and 13 621 exposures from one machine. Data were obtained from November 1998 through December 1999.

RESULTS

Using standard methods, the mean glandular dose (MGD) per exposure was 2.62 mGy (SD 1.2). The mean dose per bilateral screening examination was 6.53 mGy (SD 3.07), the median dose was 6.11 mGy, and the dose range was 1.13-34.23 mGy. Rhodium filtration was used for 18% of the exposures. The average and median breast thickness was 4.9 cm. The ACR phantom MGD for this machine was 2.44 mGy at 25 kVp, and 1.97 mGy at 26 kVp. The mean number of exposures for a bilateral mammogram was 4.9, and varied by a technologist from 4.7 to 5.2. The mean compression pressure varied by technologist from 13 to 30 lbs (58-134 N).

CONCLUSIONS

The mean dose per mammogram is slightly greater than the ACR phantom dose at 25 kVp. Almost five exposures were necessary for a standard bilateral examination, and this varied by technologist. The compression used also varied by technologist. The semiautomated collection of technical data can aid in maintaining an effective mammography QA program.