Moderate delays safe in treating colon cancer

Despite longer treatment wait times from diagnosis to surgery for patients with colon cancer – some even exceeding the 28-day recommendation by an additional two months – there seems to be no adverse impact on survival rates, according to a Western-led study.

Along with the anxiety caused by a diagnosis of colon cancer, a popular perception exists that removing the tumour as quickly as possible will improve the odds of curing the cancer.

However, delays in surgery are becoming more common. Some patients benefit from additional testing and preparation. Others might attend to work or family priorities first. Delays could also result from conflicts in hospital resources, as operating room time is a shared public resource.

No matter the reason, patients may safely have their operations reasonably delayed without any evidence it will compromise treatment outcomes, explained Dr. Kerollos Wanis, a third-year General Surgery resident with the Schulich School of Medicine & Dentistry.

His study, "Do Moderate Surgical Treatment Delays Influence Survival in Colon Cancer?," was published in the December 2017 issue of Diseases of the Colon and Rectum.

For his study, Wainis collected data on 908 patients undergoing elective surgery for stage I, II or III colon cancer from 2006-15, with a median surgical treatment wait time of 38 days.

He found patients waiting longer than 30 days from diagnosis to surgery – despite the recommended guideline set out by Cancer Care Ontario of 28 days – had similar disease-free and overall survival compared with patients with tumours resected within 30 days. There was no association between treatment delay and poorer long-term outcomes, even for patients who waited up to 90 days to receive treatment.

"Assuming that surgical consultation occurs expeditiously after diagnosis, the results of this study do not support the existing recommendations, because patients treated several weeks after diagnosis have similar survival outcomes to those treated sooner," Wanis said.

Patients who wait longer for surgery tend to voice more dissatisfaction with their overall care, when compared to those who receive immediate treatment. However, wait times are usually only one of many factors in that dissatisfaction.

Wanis hopes the clarity offered by these findings may help reduce anxiety and increase system-wide satisfaction.

"Patients who have longer delays may experience greater anxiety about their treatment, and other studies have shown they report less satisfaction with their care," he said. "It is important patients receive adequate information regarding the reasons for, and safety of, any treatment delays."

Colon cancer is easier to study, he continued, because the current treatment is surgical removal without preceding chemotherapy or radiation. The treatment for other cancers is not always so straightforward and, that said, there have been studies examining treatment delays for many other cancers, but the findings have been mixed.

"The main advantage of this kind of research is it helps to provide evidence that can inform guidelines," said Wanis, who is on academic leave from his residency to pursue a PhD in epidemiology at Harvard University. "Currently, the maximum wait time recommendations are not a reflection of the available evidence. These findings have the potential to impact the care of patients with colon cancer, at both individual patient and health-system levels.

"If treatment delays are recommended, perhaps due to further testing or preparation for surgery, then the study suggests patients should not be concerned about having worse treatment outcomes compared to others who had surgery quicker."

The study did not consider whether age or gender modified the effect of wait time on survival, but it did examine whether higher stage tumours had worse outcomes in the context of longer treatment delay. Wanis did not find stage II or III tumours did any worse than stage I tumours, but the sample size might be under-powered to detect a difference, if one truly exists.

While his research may have found surgical delays of a few weeks are safe, patients with colon cancer should continue to receive prompt and efficient care, Wanis stressed.

"Colon cancer is becoming increasingly common. If discovered at an early stage, it can be cured with surgical removal of the tumour," he said.

Patients with concerning symptoms should see their physician immediately while patients without symptoms should undergo regular screenings at the appropriate age, currently recommended to begin at age 50 and every two years after that.