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D B Kopans

Publications and source records attributed to D B Kopans.

At least 37 records · Page 2Linked to original sources
PubMed1998

Rationale for annual screening mammography for women ages 40-49 years.

Proof of the benefit for mammographic screening of women ages 40-49 years is now available. Randomized controlled trials (RCTs) conducted in Gothenburg and Malmo, Sweden have shown statistically significant breast cancer mortality reductions of 36% and 45% respectively. A meta-analysis of all five Swedish trials has found a statistically significant mortality reduction of 29% for woman in this age group. Substantially greater reductions in mortality would likely have resulted if women in these trials had been screened annually. Because the benefits are substantial, and the risks from screening are relatively small and acceptable, screening mammography beginning at age 40 is now recommended by the American Cancer Society, as well as the National Cancer Institute.

Journal Article↗
PubMed1998

Digital breast imaging: tomosynthesis and digital subtraction mammography.

Advances in the computer technology and the introduction of new digital imaging detectors offer the potential for digital image acquisition and several new mammography techniques, such as tomosynthesis and digital subtraction mammography. Tomosynthesis is a method of obtaining tomographic images of a breast. In tomosynthesis, any number of tomographic planes may be reconstructed from a set of images obtained as the X-ray source is moved in an arc above the breast. By shifting and adding the information obtained at different source positions, any plane of the breast can be brought into a sharp focus, while structures outside this selected plane are blurred. This may lead to improved lesion detection, especially in dense breast tissue. Thus, tomosynthesis may play a role in improving breast cancer screening and lesion characterization. Digital subtraction mammography is a method of breast angiography. It is performed by obtaining a digital radiographic image before, and one or more digital radiographic images after the injection of a contrast agent such as iodine. The pre- and post-contrast images are subtracted, resulting in an image of the vascular structures in the breast. Because breast cancer lesions have increased vascularity, digital subtraction mammography may play an important role in improving lesion detection, characterizing lesions, monitoring response to therapy, and determining lesion extent.Thus, both of these new digital techniques have the potential to address the major limitation of conventional mammography, namely the difficulty in detecting cancer in radiographically dense breasts.

Journal Article↗
PubMed1997

An overview of the breast cancer screening controversy.

Randomized controlled studies show that screening mammograms are as important for women aged 40-49 as for women 50 years old and above. It was the improper use of retrospective, unplanned, sub-group analysis to advise women and their physicians that caused the controversy over mammograms for women under 50. Furthermore, arbitrarily grouping women into two groups leads to the incorrect conclusion that the age of 50 is a significant break point when it is not. The data demonstrates that none of the parameters of screening change abruptly at age 50. The recall rates (an abnormal mammogram) and the rate at which biopsies are recommended are virtually the same, regardless of age. Breast cancer is not a trivial problem for women in their forties. More than 30% of the years of life lost to breast cancer are from women diagnosed while in their forties. Because of changing demographics, in 1995 and 1996, there were actually more women diagnosed with breast cancer in their forties than for women in their fifties. The data clearly show that screening women for breast cancer, on an annual basis, beginning by age 40, can reduce the death rate by approximately 24%. It is important to separate medical and scientific analyses from the economic considerations. "Society" may decide that it is too expensive to screen women for breast cancer, but women should be provided with the scientific and medical information so that they can participate in the discussion of whether screening is "worthwhile" and decide whether or not to avail themselves of its benefit. The economics should not be used to influence the scientific and medical analysis of benefit.

Adult↗
PubMed1997

Screening mammography: effect of national guidelines on current physician practice.

PURPOSE: To evaluate the effect of national breast cancer screening guidelines on current physician attitudes toward and practice of screening mammography. MATERIALS AND METHODS: Questionnaire responses from 278 physicians were analyzed. The questionnaire had four sections: general information on physician practice and experience, current use of breast cancer screening, perceptions of screening mammography, and physician awareness of and response to the controversy in breast cancer screening. RESULTS: In women aged 40-49 years, 144 (52%) of 278 physicians performed annual clinical breast examination and screening mammography every 2 years; 57 (21%) favored annual mammography and clinical breast examination. In women aged 50 years and older, 232 (83%) physicians screened patients annually with clinical breast examination and mammography. Two hundred seventeen (78%) physicians were aware of the recommended changes in screening guidelines; 54 (19%) were not aware of the changes. Of those aware of the changes, 56 (26%) changed to the new guidelines, 150 (69%) did not change, and six (3%) modified their practice somewhat. CONCLUSION: Physician practice as regards screening mammography is influenced by national guidelines.

Adult↗
PubMed1997

Digital tomosynthesis in breast imaging.

PURPOSE: To describe and evaluate a method of tomosynthesis breast imaging with a full-field digital mammographic system. MATERIALS AND METHODS: In this tomosynthesis method, low-radiation-dose images were acquired as the x-ray source was moved in an arc above the stationary breast and digital detector. A step-and-expose method of imaging was used. Breast tomosynthesis and conventional images of two imaging phantoms and four mastectomy specimens were obtained. Three experienced readers scored the relative lesion visibility, lesion margin visibility, and confidence in the classification of six lesions. RESULTS: Tomosynthesis image-reconstruction algorithms allow tomographic imaging of the entire breast from a single arc of the x-ray source and at a radiation dose comparable with that in single-view mammography. Except for images of a large mass in a fatty breast, the tomosynthesis images were superior to the conventional images. CONCLUSION: Digital mammographic systems make breast tomosynthesis possible. Tomosynthesis may improve the specificity of mammography with improved lesion margin visibility and may improve early breast cancer detection, especially in women with radiographically dense breasts.

Female↗
PubMed1997

Dynamic echo-planar imaging of the breast: experience in diagnosing breast carcinoma and correlation with tumor angiogenesis.

PURPOSE: To correlate quantitative echo-planar magnetic resonance (MR) imaging measures of gadopentetate dimeglumine tumor uptake with histologic diagnoses and microvessel density (MVD) and to compare dynamic echo-planar imaging of breast lesions with conventional dynamic MR imaging techniques. MATERIALS AND METHODS: The study group comprised 63 patients (aged 13-70 years) with 71 breast lesions who underwent conventional and echo-planar MR imaging. The T1 values, change in gadopentetate dimeglumine concentration, and extraction-flow products were calculated with the echo-planar imaging data and were correlated with histologic findings and MVD estimates. Extraction-flow product data normalized to pectoral muscle gadopentetate dimeglumine concentration in invasive cancers was also correlated with MVD. RESULTS: On average, cancer T1 values were shorter than benign values, but there was substantial overlap between the two groups. Cancers had higher extraction-flow products than benign lesions (P < .001). Sensitivity, specificity, positive predictive value, and negative predictive value were 83%, 79%, 67%, and 90%, respectively. Receiver operating characteristic analysis showed improved performance with extraction-flow products than with percentages of signal intensity change. Among the invasive cancers, there was no significant correlation between extraction-flow product and MVD. CONCLUSION: The T1 value remains important in more precise quantitative estimation of gadopentetate dimeglumine uptake in breast tumors, which helps improve the specificity of dynamic imaging. Tumor MVD affects the contrast medium enhancement of breast lesions, but other factors contribute.

Breast↗
PubMed1997

Should women with implants or a history of treatment for breast cancer be excluded from mammography screening programs?

OBJECTIVE: Our objective was to determine whether it is scientifically justified to require that women with implants or a history of treatment for breast cancer be screened in a diagnostic mammography setting and that they be excluded from mammography screening programs. MATERIALS AND METHODS: The recall rates for women with breast implants or a history of treatment for breast cancer who were screened in a dedicated mammography screening program were compared with those of other women in the screening program. The computerized records for the breast screening program of the Department of Radiology at our institution for January 1, 1990, through December 31, 1995, were reviewed. The recall rates for women who had breast implants and those for women with a history of treatment for breast cancer were compared with the recall rates for the other women who underwent screening. Each recall rate included women who were called back for additional evaluation in addition to those for whom a biopsy was recommended on the basis of the screening study. RESULTS: Of 45,134 screening examinations done during the review period, 43,454 (96%) were for women who had no history of breast cancer or of breast implants; 590 (1%) were for women who had undergone mastectomy; 991 (2%) were for women who had been treated with lumpectomy and irradiation for breast cancer; and 99 (0.2%) were for women with breast implants. Among the 43,454 examinations of women with no history of breast cancer or implants, 3081 examinations (7%) led to interpretations that produced requests for the patient to return for additional evaluation. Thirty-six women who had been treated for breast cancer by mastectomy were recalled (6%). Seventy-five women who had undergone lumpectomy and irradiation for breast cancer were recalled (8%). Five women with breast implants were recalled (5%). Statistically, these rates were not significantly different. CONCLUSION: We find no scientific reason to exclude women who have been treated for breast cancer or who have breast implants from dedicated screening programs.

Breast Implants↗
PubMed1997

Patients' opinion of mammography screening services: immediate results versus delayed results due to interpretation by two observers.

OBJECTIVE: The purpose of this study was to evaluate by random questionnaire mailings the preferences of women who have undergone mammography in our region regarding communication of mammography screening results. MATERIALS AND METHODS: Questionnaires were mailed to 400 randomly selected women who were more than 35 years old and who had been treated at our institution for medical or surgical reasons. Questions regarding use of mammography screening at our institution versus services at other locations were included. The questionnaire described two possible mammography services; either a double reading service that would provide delayed reports (DRDR) with the benefit of extra cancers detected, and a service that provides immediate reports given directly to the patient by an on-site radiologist. The presentation of the services was reversed in half the questionnaires to avoid bias. Patients' choices were collected, as were demographic data. The choice of one system over the other was evaluated using the one-sample lest for binomial probability. The chi-square test was used to determine if the order of questions on the survey or the site of patients' screening mammography affected responses. RESULTS: The response rate was 42% (n = 168). Of these, one response informed us of the death of a patient. Of the remaining 167 respondents, 75% (n = 126) preferred the DRDR system, 13% (n = 22) preferred the system providing immediate results (p < .0001), and the other 19 respondents did not select a preference. Of the 167 respondents, 156 answered the question regarding previous screening mammography experience. Of the 105 patients who had undergone screening mammography at our institution, 78% (n = 82) preferred the DRDR system. Of the 51 patients who had undergone mammography elsewhere or who had never undergone mammography, 75% (n = 38) preferred the DRDR system. We found that ordering of presentation of the systems in the questionnaire had no effect on responses. Likewise, whether a respondent had undergone mammography at our institution had no effect on responses (p = 1.0). CONCLUSION: A statistically significant number of women who responded to our questionnaire preferred the DRDR system of reporting screening mammographic results. Educational material about double reading that we included with each patient's questionnaire could account for these results. If the use of a second interpreter is feasible and is done for batch interpretation of screening mammograms, then education of patients about this process may increase acceptance of a delayed mammographic report.

Adult↗