A very large retrospective study of patients with stage II colon cancer found adjuvant therapy improves survival, regardless of treatment regimen, patient age, or high-risk pathologic risk features.1
The role of adjuvant, or postoperative, therapy in early stage colon cancer, even for high-risk cancers, has been questioned. Although adjuvant chemotherapy is known to help treat advanced colon cancer, current clinical guidelines recommend discussing this treatment option only with patients whose stage II cancer is considered high-risk and likely to return after surgery.
Colon cancer will be diagnosed in more than 95,000 people in the United States this year, according to American Cancer Society estimates. It is the second-leading cause of cancer deaths.
“The results of this study are exciting, and certain aspects not entirely expected,” said Ajay Maker, MD, associate professor of surgery in the University of Illinois at Chicago College of Medicine and director of surgical oncology for the Advocate Creticos Cancer Center. Many studies included patients with stage II colon cancer, but did not focus specifically on this disease. In this study, researchers sought to better understand the role of adjuvant chemotherapy in the treatment of this specific type and stage of cancer and includes the largest group of patients with stage II colon cancer to date, explained Maker.
Maker and colleagues reviewed health information from 153,110 patients with stage II colon cancer in the National Cancer Data Base. They found that patients who received adjuvant chemotherapy survived longer than those who did not, with some patients surviving years longer.
“Certainly, we expected to see differences in the data,” Maker said. “But to find a clinically relevant association with overall survival across all subgroups of patients, including low-risk patients, is noteworthy and very relevant to future research on the potential use of adjuvant chemotherapy as a treatment for stage 2 colon cancer.”
Noting that any look-back study of treatment and effect has limitations, Maker said, “We have to be careful when looking for associations retrospectively. However, our research validates the need for prospective studies to identify the specific subgroups of stage II colon cancer patients who may benefit most from the use of adjuvant chemotherapy.”
1. Casadaban L, Rauscher G, Akilu M, et al. Adjuvant chemotherapy is associated with improved survival in patients with stage II colon cancer. Cancer. 2016 Jul 15. doi:10.1002/cncr.30181. [Epub ahead of print]