Evaluating the benefits of postoperative chemotherapy for patients with stage II colorectal cancer

This study tested whether chemotherapy after surgery (adjuvant chemotherapy) extends survival and reduces the risk of cancer recurrence in patients with stage II colorectal cancer (CRC).

Stage II colorectal cancer (cancer in the colon or rectum) is confined to the digestive tract. It is usually treated with surgery (removal of the cancer). It is not clear whether post-operative chemotherapy should be given to these patients. 

In this article, the authors summarized results from 12 clinical trials that evaluated adjuvant chemotherapy for stage II CRC. Overall, 3830 patients underwent surgery alone and 4461 patients were given chemotherapy after surgery. Analysis included the following measures:

1. Survival rate 5-years after treatment (with and without adjuvant chemotherapy)

2. Cancer-free survival 5 years after treatment (living people cured of the disease)

3. Recurrence rate (return of the cancer)

Findings:

All evaluated measures showed significant improvement in favor of post-operative adjuvant chemotherapy:

•        Cancer mortality rate was reduced by 20% for colon and 30% for rectal cancer.
•        Cancer-free survival was increased by 14% for colon and 66% for rectal cancer.
•        The risk of recurrence was reduced by 18% for CRC altogether.

In this review, adjuvant chemotherapy provided a clear survival benefit for patients with stage II CRC and significantly reduced the risk of cancer recurrence.

However, the different trials included in this analysis used non-uniform chemotherapy regimens, limiting the strength of these findings. Also, the risks and side-effects of chemotherapy should be weighed against its benefit for each individual patient.