In this study, we examined patterns of physician visits and care receipt for breast cancer survivors versus non-cancer controls and whether survivors’ care receipt was associated with the physician mix visited. We found that, over time, survivors see their oncology providers less and their PCPs and other physicians more. Accompanying the decrease in oncology specialist involvement was a decrease in both colorectal cancer screening and mammography for survivors. However, controls’ rates of these services decreased at an equal rate as survivors. In fact, there were no differences in changes over time in care receipt between survivors and controls, so survivors were less likely than controls to receive each preventive service each year (except influenza vaccination in Year 2). Survivors, as expected, were more likely to get mammograms. Because survivors of stage 3 disease may have different projected benefits from these health services, we conducted a sensitivity analysis excluding stage 3 survivors, but the conclusions did not change. Similar to previous research, we found that survivors who visited both a PCP and oncology specialist were most likely to receive appropriate care.6,10,16
That we found consistent statistically significant differences between survivors and controls is due in part to the sample size. However, even small differences are important to the large population affected. Comparing the Year 5 rates for our survivors to the rates of survivors in the Earle et al10
study, our survivors were less likely to receive influenza vaccination (58% vs. 65%), cholesterol screening (33% vs. 48%) and mammography (64% vs. 74%) but more likely to get colorectal cancer screening (23% vs. 17%) and bone densitometry (17% vs. 8%). Importantly, Earle et al10
used a two-year window for care receipt, while we used only one-year. Because the usefulness of certain services annually is debatable, we would not necessarily expect to see high rates of each service each year. Consequently, our analyses focused primarily on comparing rates between survivors and controls and trends over time.
While we found differences in care between survivors and controls in the first five years of survivorship, Earle et al10
did not find differences between five-year survivors and controls in their cross-sectional study. In their study, survivors were more likely than controls to receive appropriate care overall. However, when controls were limited to those who had had a mammogram in the year the case was diagnosed, survivors were less likely to have a cervical exam and more likely to have mammography than controls. Controls in our study had to have had a mammogram in the year the survivor was diagnosed because prior screening practices may influence future screening practices, and we know that our survivors each had a mammogram. However, it is important to note that survivors’ mammograms may not have been for screening purposes, so requiring our controls to have had a mammogram provides a “worst case” estimate of how cases compare to controls.
The findings from this study are similar to those from previous research in colorectal cancer using the same design (but no control group).5
In both studies, we found that, over time, oncology specialists are less involved in care, survivors rely exclusively on their PCP more often, and cancer screening decreases. Adding the control group in this study is useful because we found that the decreases in cancer screening are also occurring among non-cancer controls. Whether these decreases in cancer screening are appropriate for either the survivor or control groups is an interesting question.
Our study benefits from the use of the SEER-Medicare dataset. The SEER registries provide population-based case ascertainment with rigorous quality control and inclusion of nearly all cases from the SEER regions. Linking SEER cancer data with Medicare claims provides a powerful combination of clinical and health services utilization data. However, the reliance on claims data also has limitations. For example, we have no record as to why care was not provided, and our study only included Medicare recipients in the fee-for-service program who are 65 or older. The database does not include care that was provided but not billed to Medicare. Further, our sample had limited inclusion of minorities. SEER added four more registries in 2000 to expand its coverage of minority populations, but our cohort of survivors was diagnosed in 1998.
Despite these limitations, the study’s findings have important implications. First, improved coordination between PCPs and oncology specialists in delivering follow-up care is needed. While this study did not examine care by particular oncology specialists and PCPs, it found that survivors followed by both PCPs and oncology specialists were consistently more likely to receive appropriate care. ASCO’s treatment summary and survivorship care plan templates may help facilitate communication across providers;4
however, additional interventions are likely needed. It may be appropriate to allow individual oncology specialists and PCPs to determine who is best suited to follow-up a particular breast cancer survivor. Alternatively, formalized treatment protocols that specify what services oncology specialists should provide and what services PCPs should provide may be required. Care coordination may be facilitated by cancer specialists and PCPs practicing in multispecialty groups. Research on the most efficient approach to follow-up care could help inform these policy decisions.