This article is more than 5 years old. Information may no longer be current.
Research raises questions about expensive staging modalities
SAN FRANCISCO — Although bone scan, liver ultrasound and chest X-ray frequently are used as staging tests, they were associated with low detection rates of metastases in newly diagnosed breast cancer patients, according to results of a literature review.
“We wanted to examine indications for these costly routine screening procedures,” Stuart-Allison Moffat Staley, MPH, a medical school student at the University of North Carolina School of Medicine, said at a press conference before her presentation. “We wanted to answer the question: Among women with newly diagnosed breast cancer who are otherwise asymptomatic, does evaluation with bone scanning, liver ultrasound and chest radiograph help to determine the extent of metastatic disease?”
Staley and colleagues searched PubMed and Embase databases for relevant papers. The algorithm used to achieve the primary outcome measure was defined as the number of patients with an abnormal test result divided by the total number of patients tested.
The researchers also examined false-positive and false-negative rates.
The final analysis included eight articles. The researchers pooled the results according to pathological stage to obtain overall estimates of detection rates.
For bone scan, the pooled detection rates were 1.29% for stage I, 3.09% for stage II, 2.43% for stages I and II, and 12.5% for stage III.
For liver ultrasound, the pooled detection rates were 0.47% for stage I, 1% for stage II, 0.82% for stages I and II, and 4.2% for stage III.
For chest radiograph, the pooled detection rates were 0% for stage I, 0.42% for stage II, 0.51% for stages I and II, and 4.57% for stage III.
The low detection rates, particularly for stage I and II disease, led researchers to question whether the modalities yielded adequate staging information and ultimately improved health outcomes.
“Our literature analysis suggests that these three tests are of little use in screening women for metastases, and likely result in a lot of false negatives in early-stage disease,” Staley said. “A full picture would require a head-to-head comparison of these radiological tests with more sensitive imaging, such as CT or PET.”
For more information:
Staley SAM. #Abstract 4. Presented at: 2012 Breast Cancer Symposium; Sept. 13-15, 2012; San Francisco.
Disclosure: The researchers report no relevant financial disclosures.
Perspective
Back to Top
This study reviewed the literature to determine if routine scanning (bone scan, liver ultrasound and chest X-ray) were useful in newly diagnosed patients. The authors demonstrated a very low detection rate using these tests and recommended against using them for stage I and II breast cancer. As acknowledged, they could not review the value of staging PET/CT. The highest yield was for bone scan; 3% of patients had abnormalities with stage II breast cancer while 12.5% of stage III breast cancer patients had detectable metastatic disease. This fits with our clinical impressions: Patients with locally advanced breast cancer should have some anatomic staging procedure.
The authors do not completely address the “cost” of missing the small number of patients with early-stage disease who have really have asymptomatic metastatic disease (up to 3% of bone metastasis in patients with stage II disease). On one hand, a course of adjuvant chemotherapy in these patients is unlikely to result in reduced OS; however, some harm could be performed if patients are exposed to multi-agent chemotherapy when there was no chance for cure. The authors also do not also address the small subset of patients with oligo or solitary metastases who might benefit from aggressive systemic and local approaches. Finally, as we head into the molecular era of cancer staging, we should be able to use this type of profiling to more precisely determine the subset of patients who appear to have early-stage breast cancer but have biologically aggressive tumors and could benefit from more complete anatomic staging.
Perspective
Back to Top
It strikes me that we are living in a time when we are embracing new and expensive technologies. However, we need to make sure to examine their cost and utility. Obviously, CT and MRI are used prevalently. The elephant in the kitchen is false-positive screening tests that carry along with them an excessive toll in terms of cost and anxiety. The Choosing Wisely campaign has raised a tremendous amount of awareness in rising health care costs. It has encouraged clinicians and patients to back off from these kinds of examinations that don’t improve patient outcomes and sometimes do more harm than good.
Read more about