What are the risk factors for recurrence in patients with colorectal cancer?

This study aimed to identify risk factors for recurrence (return of the cancer) in patients with colorectal cancer following surgical removal. 

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers. Treatment for CRC has generally involved surgery to remove the cancer along with the entire area (large parts of the large bowel and lymph nodes) surrounding the cancer. Because of recent advancements, it has become possible to diagnose CRC earlier, and patients can often undergo less invasive treatments, where only the cancer is removed. This, however, is more likely to lead to a recurrence, through the cancer spreading to lymph vessels or nodes. It is not fully understood which patients are more at risk for recurrence. The current study examined what risk factors may lead to CRC recurrence.

This study followed 284 patients diagnosed with early-stage CRC who underwent surgery to remove their cancer. The patients were followed for 5 years following surgery to determine what factors may lead to recurrence. Only 2.8% of patients developed recurrence after surgery. Disease-free survival (defined as the percentage of patients who were cured of the disease) at 5 and 10 years after surgery was 98.4% and 92.7%, respectively. However, the authors of the study found that patients with cancer spread to the lymph nodes (lymphatic invasion) were 11.6 times more likely to develop a recurrence.

In summary, lymphatic invasion was found to be an important risk factor for recurrence in patients with early-stage CRC treated with surgery. 

This study included a very small number of patients. Future studies involving larger populations are expected to confirm the findings of this research.