Geography Influences Type of Posttreatment Imaging Received After Early Breast Cancer

A study of over 35,000 women with early-stage breast cancer found that where you live makes a difference in terms of what kind of posttreatment imaging is received, due to geographic variation.

The authors said the results suggest that some patients are not receiving dedicated breast imaging, while other patients are receiving high-cost nonbreast imaging that may be of no benefit.

The study, published in the Journal of the National Comprehensive Cancer Network, looked at the presence and magnitude of geographic variation in use rates of both recommended and high-cost imaging during the 18 months after surgical treatment of the primary tumor.

This is a financial, ethical, and medical issue for both patients and the healthcare system as a whole, the authors noted. Oncology imaging costs are increasing at twice the rate of total cancer care costs, accounting for 4.6% of the $32.1 billion in Medicare cancer expenditures in 2009.

Surveillance strategies that lead to false positives can result in unnecessary workups, which can in turn lead to patient anxiety and risk and expense of additional procedures and radiation exposure.

Expert guidelines support routine mammography or, depending on age and other factors, dedicated breast magnetic resonance imaging (MRI) for all patients with a personal history of breast cancer. However, other nonbreast surveillance imaging, like a whole-body positron emission tomography (PET) scan to see if the cancer has recurred or metastasized, has consistently shown no benefit in terms of survival or quality of life for patients with stage I to III (nonmetastatic) disease.

Using the Truven Health MarketScan Commercial Database, a descriptive analysis was conducted of geographic variation in annual rates of dedicated breast imaging and high-cost body imaging of 36,045 women aged 18 to 64 years treated with surgery for invasive unilateral breast cancer between 2010 and 2012. In addition, they had not been exposed to neoadjuvant/adjuvant chemotherapy or trastuzumab within 18 months of diagnosis.

Multivariate hierarchical analysis examined the relationship between likelihood of imaging and patient characteristics, with metropolitan statistical area (MSA) serving as a random effect.

Patient characteristics included age group, BRCA1/2 carrier status, family history of breast cancer, combination of breast surgery type and radiation therapy, drug therapy, and payer type. All MSAs in the United States were included, with areas outside MSAs within a given state aggregated into a single area for analytic purposes.

Of 36,045 women, 24,802 (68.8%) underwent at least 1 screening or diagnostic mammogram, 4602 (12.8%) had at least 1 breast MRI, 11,418 (31.7%) had at least 1 high-cost imaging procedure, and 4490 (12.5%) had at least 1 PET scan.

A total of 25,501 women (70.8%) had at least 1 dedicated breast image (ie, at least 1 mammogram or breast MRI).

Descriptive analysis of rates of imaging use and intensity within MSA regions revealed wide geographic variation, irrespective of treatment cohort or age group.

Increased probability of recommended postoperative dedicated breast imaging was primarily associated with age and treatment including both surgery and radiation therapy, followed by MSA region (odds ratio [OR], 1.42).

Increased probability of PET use was primarily associated with surgery type followed by MSA region (OR, 1.82).

Reference

Franc BL, Copeland TP, Thombley R, et al. Geographic variation in postoperative imaging for low-risk breast cancer. J Natl Compr Canc Netw. 2018;16(7):829-837. doi: 10.6004/jnccn.2018.7024.