Trends in the Treatment of Advanced Stage Colon and Rectal Cancer

The appropriateness of aggressive, expensive, and only modestly effective chemotherapy for patients with advanced incurable cancer remains uncertain. This study provides new evidence about the trends in population-based treatment and costs following diagnosis for two incurable cancers, advanced colon and rectal cancer, in elderly adults. We used data from the Surveillance, Epidemiology, and End Results (SEER) – Medicare linked database for persons aged 65 and older and diagnosed with advanced colon (N=16084) or rectal cancer (N=4003) between 2000 and 2009.  For each year, the adjusted percent of patients who received chemotherapy, hematopoietic growth factors, and chemotherapy supportive drugs and their mean costs during the year following diagnosis were the main outcome measures. For those who received chemotherapy, we estimated the mean number of days from the first to the last chemotherapy claim and the percent who received three or more agents. In addition, we estimated survival probabilities for the 24 month period following diagnosis. From 2000 to 2009, decreasing numbers of patients had inpatient surgery. 

Over the study period, the percent of patients who received chemotherapy increased modestly. However, new chemotherapeutic agents (primarily oxaliplatin and bevacizumab) were rapidly adopted. Supportive chemotherapy drugs and growth factor use also dramatically increased, leading to substantial increases in treatment costs. Average one-year treatment costs per patient were $74,629 for colon and $82,016 for rectal cancers, reflecting an increase of over $10,000 during the study period. The proportion of costs due to hospitalizations declined (colon: 56% to 47% and rectal: 47% to 40%).  Hospice care increased by more than 20 percentage points over the study period. In spite of these changes in practice patterns, only modest gains in survival were observed.

Our findings demonstrate that there are opportunities for more efficient use of resources. For example, 80% of patients in our sample were age 70 years and older. By 2009, a third of the patients who received chemotherapy, received oxaliplatin. At least one clinical trial that enrolled patients with stage II or III colorectal cancer found no survival benefit from the addition of oxaliplatin to 5-FU and leucovorin in patients aged 70 to 75 years. Furthermore, our study provides evidence that among chemotherapy patients, more than 70% receive three or more agents, although there is little evidence to support the use of these combinations in advanced stage patients. In spite of shifts in treatment away from surgery to outpatient and palliative and hospice care, the cost to treat incurable colon and rectal cancer has risen dramatically. Using national estimates of colorectal cancer incidence (colon N=102,480 and rectal N=40,340) and the most recent stage at diagnosis distribution (approximately 20% diagnosed with distant disease) and applying the Medicare costs from our study, national costs of colorectal cancer care in the first year after diagnosis would be approximately $2.2 billion in 2013. A more judicious use of treatment that considers decrements in quality of life along with substantial increases in costs may lead to more conservative management of patients whose prognosis in poor.