Combined Risk Factors Lead to Worse Outcomes in Colon Cancer

Luv N. Hajirawala, MD, a resident in the section of Colon and Rectal Surgery at LSU Health New Orleans School of Medicine, discusses the findings from a retrospective analysis of the Surveillance, Epidemiology and End Results (SEER) database looking at patients with stage III colon cancer.

According to Hajirawala, the investigators used the SEER database to learn how high-risk features, including pathological T4 disease, perineural-invasive disease, lymphovascular invasion, and inadequate lymphadenectomy, increase overall survival (OS) and cancer-specific survival (CS) in patients with later-stage disease. These factors are known to be associated with risk of recurrence and worse survival outcomes following resection in patients with stage II disease.

The investigators found that among 35,760 patients with stage III colon cancer from 2010 to 2017, T4 disease had the worst outcomes out of the selected risk factors, with an OS rate of 57.2%, while inadequate lymphadenectomy, poorly differentiated disease, and perineural disease had an OS of 64.6%, 66.6%, and 66.4% respectively.

Those with stage III disease with no high-grade risk factors had an OS of 73.3% and CS of 81.4%, while those with 1 risk factor had an OS rate of 63.7% and CS of 71.6%. However, for patients with 2 or more risk factors, OS was 44.0% and CS was 51.0%, which is worse than that of any individual risk factor. This demonstrates that these risk factors are cumulative in increasing risk for patients, says Hajirawala.

TRANSCRIPTION:

0:08 | What we wanted to look at was, how does the presence of high-risk features affect the patient's OS and CS? Patients who had 1 high-risk feature had a worse OS and CS compared [with] patients who did not have any. And when we looked at more than 2 high-risk features, that OS and CS [were] even lower. What we wanted to know then was, is this because of a single risk factor, or do all of them have a combined effect on it?

What we looked at next was how individual risk factors impact OS and CS in patients with stage III disease. We found that less than 12 lymph nodes [harvested in an] inadequate lymphadenectomy, high-grade disease, and perineural disease all have about a similar impact on the overall and cancer-specific survival. They bring OS down to 65% in that range, and T4 disease had more pronounced effect on this. T4 disease brings your OS down to 57%.

1:23 | But what we found then was that patients who had [2 or more] risk factors, their survival was almost 44% for OS, and 51% for CS, which is lower than the lowest survival conferred by any individual high-risk feature. So, what we can surmise is that if you have [2 or more] risk factors, the effect on survival is cumulative.