Growing Number of Cancer Survivors Among Aging Population as Baby Boomers Pass the 65-Year Mark

A recent epidemiology study by the National Cancer Institute (NCI) has found an almost four-fold increase in the number of cancer survivors since 1971: 11.9 million in 2008 compared with 3 million in 1971-and the authors of the study expect a 42% increase in the number of older survivors in the next 10 years. These results are part of an annual ongoing series on the analysis of cancer prevalence, which should guide further exploration of this trend by the NCI.

The NCI has been supporting the Surveillance Epidemiology and End Results (SEER) tumor registry program for 38 years to provide public information on the collective effort to decrease the burden of cancer in the United States since 1973, 2 years after the National Cancer Act came into effect. These latest survivorship analyses are published in the October issue of Cancer Epidemiology, Biomarkers & Prevention, an American Association for Cancer Research journal. The analysis of the SEER data was done through the Office of Cancer Survivorship (OCS) at the NCI by Julia Rowland, PhD, the director of the OCS.

That age is the most important risk factor for developing cancer is well emphasized by the analysis of the latest prevalence data: 53.8% of cancers occur after the age of 65, with breast and ovarian cancers being the exceptions.

The authors highlight the importance of addressing the needs of older cancer patients and survivors in light of the fact that the oldest baby boomers turned 65 in January of this year. By 2030, the number of US citizens who are 65 or older will have increased by 19% to 46.5 million. Furthermore, the number of people age 85 or older is estimated to triple from 5.7 million in 2008 to 19 million in 2050.

The largest cancer survivorship populations are those of breast (22%), prostate (20%), and colorectal cancers (9%). Surviving these three cancers is attributed to better technology of detection and screening methods over the last 30 years. "We can expect a dramatic increase in the number of older adults who are diagnosed with or carry a history of cancer," said Rowland. "Cancer is largely a disease of aging, so we’re seeing yet another effect of the baby boom generation and we need to prepare for this increase," she added.

The SEER program has been gathering data on approximately 28% of the US population and releases cancer incidence and mortality statistics every April. SEER also estimates cancer prevalence, the number of individuals alive at a given time that have a history of cancer. Cancer prevalence is quite difficult to capture accurately because it’s necessary to obtain all history of cancer diagnosis as well as up-to-date vital status. This is not always possible, as some registries have not been set up to capture prior cancer diagnosis history and follow-up data.

Of course, awareness of the increase in cancer survivors is also important in the context of the US healthcare system. According to the authors, volume, increased cost, and complexity of cancer treatment will have implications on the delivery of healthcare. Aging cancer patients and survivors also likely have comorbidities and chronic conditions that need to be considered; comorbidities can complicate treatment and diagnosis of older patients. Rowland and colleagues also point out that the larger cancer survivor population will also have a greater risk of developing subsequent cancers. Approximately 16% of newly diagnosed cancer cases occur in those who have had a prior cancer history.

Rowland stresses that the healthcare community needs to prepare for the large number of cancer survivors that will be present in the US healthcare system. However, "we may be fortunate in that the aging population is healthier than in previous generations, and new technologies could allow for better communication and follow-up," Rowland said.

The authors highlight that older adults are generally an "overlooked, understudied, and underserved and vulnerable group of cancer survivors." Less than 10% of National Institute of Health (NIH)-funded grants focus their research on the health of individuals 65 years and older. Rowland and colleagues urge the onset of prospective epidemiologic and survivorship studies in older adults. Additionally, the researchers cite psychosocial and behavioral research in addition to better data on patients from primary diagnosis to prevention as important areas of focus for future research.