25 August 2016

Patients with metastatic (Stage IV) breast cancer often undergo frequent blood tests and scans to monitor for disease progression. But is there such a thing as too much testing?

A study recently published in the Journal of the American Society of Clinical Oncology evaluated the use of blood tests (tumor markers) and body imaging scans (such as PET, CT, or bone scans). The Medicare-SEER database was used to identify women diagnosed with metastatic breast cancer from 2002-2011, and billing codes were then assessed to determine test utilization. Among 2460 eligible patients, 36.7% were “extreme users” of disease monitoring tests, defined as greater than 12 blood tests and/or 4 body imaging scans in a 12 month period. Medical costs were 59.2% higher in these patients.

Metastatic breast cancer is not curable. Patients with Stage IV breast cancer often are treated with some form of chemotherapy, hormonal therapy, or targeted therapy for life. The location and amount of tumor in the body are monitored using blood tests and body imaging, and treatments are adjusted if the disease progresses. How much monitoring is appropriate varies depending on the individual situation and whether or not a patient is participating in a clinical trial (some trials have specific requirements for testing). However, the authors of an accompanying editorial note that no clinical trial requires monthly blood tests or body imaging more than four times per year.

Intuitively, it would seem that the sooner progression is identified and treatment initiated (or changed), the better the prognosis. However, that is not yet the case. As novel treatments are discovered, this may change over time. But for now, more testing only adds to higher costs. As Dr. Leonard Lichtenfeld, the Deputy Chief Medical Officer of the American Cancer Society noted in his blog post: “No one likes to think of costs when it comes to medical care and especially when saving lives. But while a lab test or an imaging study may not make a difference to our care or the outcome of our illness it certainly does make a difference to our pocketbook. And even worse, it may give us a false sense of comfort when it doesn’t accurately reflect a change in our disease, or send us down another perhaps more toxic path of treatment when it wouldn’t make a difference to do so.”