Breast cancer screening

Simulation and evaluation of a high resolution VIP PEM system with a dedicated LM-OSEM algorithm

Over the last two decades there have been a growing number of designs for positron emission tomography (PET) cameras optimized to image the breast. These devices, commonly known as positron emission mammography (PEM) cameras allow much more spatial resolution by putting the photon detectors directly on the breast. PEM cameras have a compact geometry with a restricted field of view (FOV) thus exhibiting higher performance and lower cost than large whole body PET scanners. Typical PEM designs are based on scintillators such as bismuth germanate (BGO), lutetium oxorthosilicate (LSO) or lutetium yttrium orthosicilate (LYSO), and characterized by large parallax error due to deficiency of the depth of interaction (DOI) information from crystals. In the case of parallel geometry PEM, large parallax error results in poor image resolution along the vertical axis. In the framework of the Voxel Imaging PET (VIP) pathfinder project, we propose a high resolution PEM scanner based on pixelated solid-state CdTe detectors. The pixel PEM device with a millimeter-size pixel pitch provides an excellent spatial resolution in all directions 8 times better than standard commercial devices with a point spread function (PSF) of 1 mm full width at half maximum (FWHM) and excellent energy resolution of down to 1.6% FWHM at 511 keV photons at room temperature. The system is capable to detect down to 1 mm diameter hot spheres in warm background.

Decision analysis for cancer screening in idiopathic venous thromboembolism

BACKGROUND

The SOMIT trial randomized patients with idiopathic venous thromboembolism (IVTE) and without signs of cancer at routine medical examination, to extensive screening for cancer plus 2 years of follow-up or to just 2-year follow-up.

METHODS

The data of the SOMIT-trial were used to perform a decision analysis. The screening tests were divided in several possible strategies. The number of detected cancer patients and the number of patients investigated further for an eventually benign condition were calculated for each strategy. The total costs for the screening strategy and for each detected cancer patient were determined. Based on the tumor type, stage, age and gender of the individual cancer patient, the difference in live years gained (LYG) was calculated between the two study groups.

RESULTS

Computed tomography (CT) of the abdomen combined with sputum cytology and mammography detected 12 of the 14 patients with cancer and had one false-positive result. In general, screening strategies including abdominal/pelvic ultrasonography (US) or tumor markers yielded a higher number of patients needed to screen in comparison with those using abdominal/pelvic CT. Furthermore, the strategies which included colonoscopy, tumor markers, and abdominal/pelvic US were significantly more costly, had inferior LYG and higher costs per LYG, when compared with strategies using abdominal/pelvic CT.

CONCLUSIONS

Despite the limitations of this analysis, the screening for cancer with a strategy including abdominal/pelvic CT with or without mammography and/or sputum cytology appears potentially useful for cancer screening in patients with IVTE. The cost-effectiveness analysis of this strategy needs confirmation in a large trial.

Multiparametric and multinuclear magnetic resonance imaging of human breast cancer: current applications

The exploration of novel imaging methods that have the potential to improve specificity for the identification of malignancy is still critically needed in breast imaging. Changes in physiologic alterations of soft tissue water associated with breast cancer can be visualized by magnetic resonance (MR) imaging. However, it is unlikely that a single MR parameter can characterize the complexity of breast tissue. Techniques such as multiparametric MR imaging, proton magnetic resonance spectroscopic (MRSI) imaging, and 23Na sodium MR imaging when used in combination provide a comprehensive data set with potentially more power to diagnose breast disease than any single measure alone. A combination of MR, MRSI, and 23Na sodium MR parameters may be examined in a single MR imaging examination, potentially resulting in improved specificity for radiologic evaluation of malignancy.

Relationships of practitioner communications and characteristics with women's mammography use

Women have reported not seeking mammography because their practitioners do not recommend it. The purposes of this study were to delineate which dimensions of practitioner communications and characteristics predicted women's mammography use. In a longitudinal, correlational design, participants were 797 mid-western women, aged 51-80 years, who had not had mammograms in the prior 13 months. Practitioner communications and characteristics and women's subsequent mammography use were assessed through telephone interviews with participants. Controlling for pre-existing differences, communications and characteristics were entered in a hierarchical logistic regression on mammography use. Practitioner-specific communications predicted mammography use (e.g. endorsement, encouragement, and assistance with scheduling) as well as having internists as identified practitioners. Practitioners' mammography-specific communications can promote mammography among women who have not used it often in the past. Practitioners--especially those who are not internists--can examine whether their interactions are conducive to fostering mammography use.

Tailored messages, external barriers, and women's utilization of professional breast cancer screening over time

BACKGROUND

The efficacy of tailored messages on women's utilization of professional breast screening over time has not been examined often or in combination with external barriers (e.g., costs and access). The objectives of this study were to test the effects of alternative messages on mammography and clinical breast examination (CBE) utilization over time and to examine the combined effects of such messages and external barriers.

METHODS

In a randomized, controlled trial, three message conditions were compared: no message (control group), recommendations about screening, or recommendations plus tailored discussion (on beliefs, feelings, costs, and access). Messages were delivered by advanced practice nurses over the telephone. Participants were women ages 51-80 years who had not had mammography in the prior 13 months. Outcome measures were women's mammography and CBE utilization 3-6 months postintervention (short-term follow-up) and 13-16 months after short-term follow-up (long-term follow-up).

RESULTS

Both messages promoted mammography and CBE utilization at short-term follow-up. Utilization increased over time in all groups. Mammography utilization was greater for the tailored-message group compared with the recommendations-only group at long-term follow-up. Messages and external barriers had combined effects (Ps < 0.01). Among participants with high external barriers, participants in the message conditions-especially the tailored message-had the highest screening rates; among participants with low barriers, screening rates were similar across conditions.

CONCLUSIONS

Clinicians can tailor discussions on beliefs, feelings, cost, and access about screening to promote professional breast screening over time, especially with women who have not had mammograms as recommended and who have external barriers to screening.

Nuclear medicine in primary breast cancer imaging

The application of nuclear medicine techniques to study patients with breast cancer has recently raised its profile, particularly in the investigation 'indeterminate mammographic lesions'. This review briefly points out some of the difficulties encountered with other more conventional imaging modalities and describes the radionuclide techniques most frequently employed in the investigation of those patients with breast cancer. Both planar and single photon emission tomography methods are discussed including the use of monoclonal antibodies, perfusion ligands, receptor binding hormones and other specific radiotracers, non-specific tumour markers, as well as deoxyglucose and other amino acids labelled with positron emitting radionuclides.

Breast cancer risk following irradiation for Hodgkin's disease

Radiation is commonly used to treat early-stage Hodgkin's disease. As the risk of recurrent Hodgkin's disease decreases as time from treatment elapses, the risk of radiation-induced breast cancer rises. Women irradiated between the time of puberty and the age of 30 are at the highest risk. The median time to breast cancer following radiation in this age group is approximately 15 years, usually when women are aged between 30 and 40, and often before regular breast screening is implemented. Risk factors associated with breast cancer development include age at irradiation, time since treatment and the radiation dose received. Current screening for breast cancer after Hodgkin's disease is inconsistent. In this article we review breast development, mechanisms of radiation-induced carcinogenesis, and findings from retrospective studies on Hodgkin's disease and breast cancer. We also review future considerations of management, including assessment of risk awareness in these women, guidelines for follow-up and screening, and chemoprevention both during and after treatment of Hodgkin's disease. The literature reviewed was obtained from Medline using the key words: breast cancer, Hodgkin's disease and radiation-induced cancer. The search was limited to English language literature. Other sources include reference lists in books and published papers.

Evaluation of the quality of self-education mammography material available for patients on the Internet

RATIONALE AND OBJECTIVES

The Internet offers many advantages for educating patients but has no standards for publication. This limitation could negatively affect patient care. The purpose of this study was to evaluate the quality of information on mammography that a patient could find on the Internet.

MATERIALS AND METHODS

Three search utilities were used to research the term "mammography." For each utility, the first 50 addresses for Web pages were evaluated (or all the addresses, if fewer than 50 were returned). Web sites selected contained information that could guide an asymptomatic woman in deciding whether to undergo screening mammography. These sites were then evaluated for whether they indicated their sponsorship, authorship, the currency of information, and references. Sites were also noted if they advised women older than 50 years to undergo screening mammography at intervals of longer than 1 year or otherwise severely diminished the role of mammography.

RESULTS

Thirty-eight Web sites were identified. Ten indicated authorship, 29 indicated the currency of the information, and 27 provided references. All of the Web sites indicated sponsorship. Three sites recommended screening mammography at intervals of longer than 1 year for women 50 years of age or older. Two sites suggested that mammography is not substantially more sensitive than physical examination.

CONCLUSION

Many Web sites do not meet the standards for disseminating information required in professional peer-reviewed journals. Some Web sites contain statements that might lead asymptomatic women over age 50 years to delay screening mammography or to undergo screening at intervals of longer than 1 year.

Screen-detected breast cancers have a lower mitotic activity index

We know that screening for breast cancer leads to detection of smaller tumours with less lymph node metastases. Could it be possible that the decrease in mortality after screening is not only caused by this earlier stage, but also by a different mitotic activity index (MAI) of the tumours that are detected by screening? Is MAI a prognostic factor for recurrence-free survival? A retrospective study was carried out of 387 patients with breast cancer, treated at the University Hospital Nijmegen between January 1992 and September 1997. Ninety patients had screen-detected breast cancer, 297 patients had breast cancers detected outside the screening programme. The MAI, other prognostic factors and recurrence-free survival were determined. In non-screen-detected tumours the MAI is twice as high as in screen-detected tumours, even after correction for age took place. The MAI correlated well with other tumour characteristics. The MAI in itself is a prognostic factor for recurrence-free survival. Favourable outcome in screen detected breast cancer is not entirely caused by detecting cancer in early stages: quantitative features such as the MAI indicate a less malignant character of screen detected breast cancer. The MAI is an independent prognostic factor for recurrence-free survival.

Principles of screening

Preventive medicine is an increasingly important area of clinical practice. Conceptually, preventive medicine involves three tasks of the clinician: screening, counseling, and immunization/prophylaxis. This opening article reviews some of the basic tenets underlying screening including basic epidemiologic principles, characteristics of a good screening situation, barriers to screening, and some of the potential hazards of screening.

Pacemaker interference with screening mammography

In female pacemaker recipients undergoing screening mammography, the impact of a pulse generator placed in the pectoral region has yet to be reviewed. We evaluated mammograms from 74 female pacemaker patients aged 40 years and older. The pulse generator obscured a portion of the mammogram in 7 patients (12%). During pacemaker implantation in women, the potential for the pulse generator to interfere with screening mammography should be considered. Baseline mammography should be obtained or reviewed; in high risk patients a nonconventional location for the pulse generator may be appropriate.