Adjuvant chemotherapy appears to offer a survival benefit to patients aged 75 years or older who have surgically resected colorectal cancer, according to the results of a study published in the Journal of Clinical Oncology.
Colorectal cancer is the second leading cause of cancer death in the United States. Stage III colon cancer refers to cancer that has spread to lymph nodes surrounding the colon but not to other parts of the body. Adjuvant chemotherapy refers to chemotherapy that is delivered after surgery in order to increase the chances of a cure.
Patients older than age 75 represent a large number of those who are diagnosed each year with colorectal cancer; however there is little data to support adjuvant chemotherapy in this population because older people are often excluded from clinical trials. To evaluate the effectiveness of adjuvant chemotherapy in this patient population, researchers performed a retrospective analysis of data from four sources: the Surveillance, Epidemiology, and End Results (SEER) database and the New York State Cancer Registry (NYSCR), both of which are linked to Medicare programs and the NCCN Outcomes Database and the Cancer Care Outcomes Research and Surveillance Consortium (CanCORS).
The study included data from 5,489 patients aged 75 or older with stage III colorectal cancer diagnosed between 2004 and 2007. The patients were categorized into two groups: chemotherapy or no chemotherapy. Those who underwent chemotherapy were further categorized to determine whether their chemotherapy included Eloxatin® (oxaliplatin).
The results of the analysis indicated that the use of chemotherapy declined with age and comorbidity. Patients who received chemotherapy had significantly better survival than those who did not. In fact, the researchers found that the survival benefit was equal to that seen in clinical trials of younger patients. Chemotherapy that included Eloxatin appeared to be associated with a trend toward lower mortality in two of the four data sets.
The researchers concluded that patients aged 75 and older with stage III colorectal cancer may experience a survival benefit with adjuvant chemotherapy. They suggest that adjuvant therapy in this older patient population is worth considering, depending on individual health characteristics.
Sanoff HK, Carpenter WR, Stürmer T, et al. Effect of adjuvant chemotherapy on survival of patients with stage III colon cancer diagnosed after age 75 years. Journal of Clinical Oncology. 2012; 30(21): 2624-2634.