Patients with incurable cancer continue to undergo routine cancer screening, according to a study published in the Journal of the American Medical Association (2010;304:1584).
The study, led by Camelia Sima, MD, MS, from Memorial Sloan-Kettering Cancer Center, evaluated the extent to which patients with advanced cancer continue to be screened for new cancers. The researchers believed that despite the lack of benefit of screening procedures, a small proportion of patients with advanced cancer continue to be screened for cancers other than their primary tumor. “It takes several years before clear survival benefit from cancer screening becomes apparent,” explained Stephen Taplin, MD, chief of the National Cancer Institute (NCI) Applied Cancer Screening Research Branch. “With breast cancer, for example, it takes at least 3 to 5 years after a screening test before fewer women in a screened group die than an unscreened group. That means that a woman needs to have a minimum life expectancy of at least 3 to 5 years to have breast cancer screening affect the length of her life in a meaningful way.”
Using information from the Surveillance, Epidemiology, and End Results (SEER) tumor registries, Dr. Sima and her team assessed the utilization of cancer screening procedures in 87,736 Medicare recipients 65 years or older who had advanced lung, colorectal, breast, gastroesophageal, or pancreatic cancer.
A control group of 87,307 Medicare enrollees without a cancer diagnosis from a random SEER sample were matched by age, sex, race, and geographic location to the cancer patients. Overall, the rates of screening among the patients with cancer ranged from 35% to 55% of the rates observed in the cancer-free control subjects.
In both groups, higher socioeconomic status and being married were significantly associated with a higher probability of being screened, and the strongest predictor of screening in the cancer patients was having undergone screening previously, before a cancer diagnosis.
“The most plausible interpretation of our data is that efforts to foster adherence to screening have led to deeply ingrained habits,” the authors wrote. “Patients and their health care practitioners accustomed to obtaining screening tests at regular intervals continue to do so even when the benefits have been rendered futile in the face of competing risk from advanced cancer … [a] culture of screening on ‘autopilot.'”
Julia Rowland, MD, director of the NCI Office of Cancer Survivorship, explained that while some women with metastatic breast cancer can live for more than 5 years after treatment and may benefit from continued screening for other types of cancer, there needs to be an individual discussion between doctor and patient.
According to the study’s authors, the situation is aggravated by the lack of “intelligent” technology that could help flag potentially unnecessary screening tests. Patients and physicians may also have difficulty discussing a poor prognosis and end-of-life issues. However, Dr. Rowland explained that the communication flaws exposed in the paper go beyond end-of-life discussions and highlight the lack of communication between doctors and patients about the risks and benefits of the screening procedures being performed. ■