Future Directions in Breast Imaging

Recent trends in mammography utilization in the Medicare population: is there a cause for concern?

CONTEXT

Recent published reports have shown a decline in the mammography screening rate in women over age 40, but it is not known whether this trend is a reason for concern in the Medicare population.

OBJECTIVE

To study recent trends in mammography utilization in the Medicare population and determine how the newer digital mammography may be affecting mammography utilization.

DESIGN AND SETTING

The Centers for Medicare & Medicaid Services Physician/Supplier Procedure Summary Master Files for 1996 through 2005 were examined to determine overall trends in mammography utilization, as well as trends in screening vs diagnostic and conventional screen-film vs newer digital examinations. Medicare Limited Datasets for 2002 to 2004 were used to determine 2-year mammography and multiple imaging rates in individual patients.

MAIN OUTCOME MEASURE

Mammography utilization.

RESULTS

Overall, the mammography utilization rate increased from 26,646 per 100,000 in 1996 to 39,363 per 100,000 in 2005, a 48% increase. The diagnostic mammography rate decreased by 39% (from 15,314 to 9,301), whereas the rate for screening mammography increased by 166% (from 11,332 to 30,062). Digital mammography increased from 2.2% of all mammography in 2002 to 10.4% in 2005. In both digital and film mammography, screening increased more rapidly than diagnostic mammography.

CONCLUSIONS

The utilization rate of all mammography showed a substantial 48% increase between 1996 and 2005, and an 11% increase in screening mammography was seen between 2000 and 2005. Although the increase in mammography utilization is encouraging, the 2005 rate of 39,363 per 100,000 female Medicare beneficiaries seems to be well below American Cancer Society recommendations.

Knowledge, attitude and practice of mammography among women users of public health services

OBJECTIVE: To evaluate knowledge, attitude and practice related to mammography among women users of local health services, identifying barriers to its performance. METHODS: A total of 663 women were interviewed at 13 local health centers in a city of Southeastern Brazil, in 2001. Interviewees were randomly selected at each center and they were representative from different socioeconomic conditions. The number of interviewees at each center was proportional to monthly mean appointments. For data analysis, answers were described as knowledge, attitude, practice and their respective adequacies and then they were correlated with control variables through the chi-square test. RESULTS: Only 7.4% of the interviewees had adequate knowledge on mammography, while 97.1% of women had an adequate attitude. The same was seen for the practice of mammography that was adequate in 35.7% of the cases. The main barrier to mammography was lack of referral by physicians working at the health center (81.8%). There was an association between adequacy of attitude and five years or more of education and being married. There was also an association between adequacy of mammography practice and being employed and family income up to four minimum wages. CONCLUSIONS: Women users of local health services had no adequate knowledge and practice related to mammography despite having an adequate attitude about this exam.

Fluorescent fructose derivatives for imaging breast cancer cells

Breast cancer cells are known to overexpress Glut5, a sugar transporter responsible for the transfer of fructose across the cell membrane. Since Glut5 transporter is not significantly expressed in normal breast cells, fructose uptake can potentially be used to differentiate between normal and cancerous cells. Fructose was labeled with two fluorophores at the C-1 position: 7-nitro-1,2,3-benzadiazole (NBD) and Cy5.5. The labeling site was chosen on the basis of the presence and substrate specificity of the key proteins involved in the first steps of fructose metabolism. Using fluorescence microscopy, the uptake of the probes was studied in three breast cancer cell lines: MCF 7, MDA-MB-435, and MDA-MB-231. Both fluorescent fructose derivatives showed a very good uptake in all tested cell lines. The level of uptake was comparable to that of the corresponding glucose analogs, 2-NBDG and Cy5.5-DG. Significant uptake of 1-NBDF derivative was not observed in cells lacking Glut5 transporter, while the uptake of the 1-Cy5.5-DF derivative was independent of the presence of a fructose-specific transporter. While 1-NBDF showed Glut5-specific accumulation, the coupling of a large fluorophore such as Cy5.5 likely introduces big structural and electronic changes, leading to a fructose derivative that does not accurately describe the uptake of fructose in cells.

Phosphocholine as a biomarker of breast cancer: Molecular and biochemical studies

The discovery of metabolic and molecular markers that help improving the detection and diagnosis of breast cancer is an important goal to be achieved. A high composite-choline signal in magnetic resonance spectra of breast lesions has been demonstrated to improve the accuracy of breast cancer diagnosis. In the present study we revealed the principal molecular and biochemical steps associated with the induction of choline metabolism and phosphocholine accumulation in human breast cancer cell-lines in comparison with normal human mammary epithelial cells. We found upregulation of the expression levels of specific choline transporters: organic cation transporter-2 and choline high affinity transporter-1, as well as of the enzyme choline kinase alpha in the cancerous cells in comparison with that in the normal mammary epithelial cells. The expression levels of choline transporter like-1, organic cation transporter-1 and choline kinase beta were similar in normal and cancerous cells. We further showed that choline transport rates and choline kinase activity indeed increased by several fold in the cancer cells leading to the elevation of phosphocholine. The results strongly suggest that phosphocholine can serve as a biomarker of breast cancer reflecting upregulation of specific choline transporters and choline kinase genes.

Identifying and Screening Patients at Risk of Second Cancers

BACKGROUND

The average age of the U.S. population is increasing, and cancer incidence increases with age. Both improved early detection of first malignancies and effective primary oncologic therapy have led to prolonged survival, and the risk of secondary malignancies has consequently increased. A few anatomic sites are at increased risk for second malignancies within the same organ: breast, colon and rectum, lung, head and neck (or upper aerodigestive malignancies), prostate, and the uterine cervix. Some of the cancers also incur a risk for a second malignancy at another anatomic site. In addition, there are well-described clinical genetic syndromes that, as unique clinical entities, predispose to second malignant tumors.

METHODS/RESULTS

In this review, we focus on issues related to the risk of second malignancies among patients with primary breast, colon, lung and head and neck, prostate, and cervical cancers that comprise the most common sites of primary malignancy among patients in the United States. We review recent data related to both established and new screening strategies at these sites.

CONCLUSIONS

There is some evidence that screening will improve outcomes among patients who may develop second malignancies, although the data are limited. The optimal screening modalities and strategies to reduce mortality from second malignancies remain to be defined for most tumor sites.