Fahima Dossa, MD
Findings from a recent study suggest that physicians should consider a watch-and-wait approach for patients with rectal cancer who have a clinical complete response to neoadjuvant chemoradiation. Although the safety of this approach is unclear, it could potentially save patients from the morbidity of conventional surgery, which may affect their bowel and sexual function.
MEDLINE, Embase, and the grey literature were searched for studies of patients who had been managed by the watch-and-wait approach. Through this process, it was determined that among 867 patients across 23 studies, the pooled 2-year local regrowth was 15.7% (95% CI, 11.8-20.1).
No significant difference in overall survival was found between patients managed with watch-and-wait and patients who had undergone surgery (HR, 0.73; 95% CI, 0.35-1.51). Additionally, no significant difference was found in nongrowth recurrence (risk ratio [RR], 0.58; 95% CI, 0.18-1.90), cancer-specific mortality (RR, 0.58; 95% CI, 0.06-5.84), disease-free survival (HR, 0.56; 95% CI, 0.20-1.60), or overall survival (HR, 3.91; 95% CI, 0.57-26.72). Although, the rate of disease-free survival in the surgery group was better than in the watch-and-wait group, (HR, 0.47; 95% CI, 0.28-0.78).
In an interview with OncLive
, study authors Fahima Dossa, MD, surgical resident, St. Michael’s Hospital, and Nancy Baxter, MD, PhD, chief of the General Surgery Department, St. Michael’s Hospital, discussed the potential of using a watch-and-wait approach in the management of patients with rectal cancer.
OncLive: What was the intent behind this study?
: The reason why this study was done dates back to 2004. A group from Brazil decided to try to treat patients with rectal cancer differently than the convention. Previously, the convention would have been neoadjuvant chemoradiation surgery and then adjuvant therapy after that with chemotherapy.
As we mentioned in the paper, there is a minority of patients that have an excellent response to neoadjuvant treatment, and when they are taken for surgery, there is no sign of the tumor. So, this group from Brazil decided that it was worth looking at whether these patients really benefitted from surgery at all. Unfortunately, we cannot identify these patients, except for at the time of surgery when their pathology is looked at.
This group developed a set of clinical parameters that they used to see who was likely to have a complete pathologic response. They took those patients and offered them the option of watching and waiting, rather than surgery. Essentially, it is close follow-up with regular endoscopy and regular imaging and regular clinic visits. And they had pretty good results. They had very good long-term survivals and low rates of tumor recurrence. But there were some questions of will these tumors come back and what happens to these patients when their tumors do come back. A lot of other groups have tried to investigate this but most of the studies are quite small, so it is hard to draw conclusions from them.
Could you provide an overview of the study that you conducted?
Dossa: The study is designed as a systematic review and meta-analysis. We searched 3 common databases as well as a series of grey literature to try to find any studies by which any patients were managed by this watch-and-wait approach. We looked at studies in which any patients were treated by this approach, and then we looked at studies where patients were treated by a watch-and-wait approach versus patients that were treated with surgery, and we compared outcomes in those groups. All of the patients had locally advanced rectal cancer and the ones who were treated with watch-and-wait were identified as having a complete response based on clinical parameters. The surgical group was divided between those that had a clinical complete response and those who had a pathologic complete response.
What were the significant findings?
Dossa: The primary outcome for our study was the rate of regrowth. So, how often the tumor regrew in the lumen of the rectum. Specifically, we looked at the 2-year rate of regrowth. Previous studies have shown that within the first 2 years are when the patient has the highest risk for the tumor to regrow. What we found that was that the rate of regrowth was 15%, so 15% of patients have their tumor come back, but the rest of the patients were spared from surgery.
One of the important findings of our study was that of those 15% that did have regrowth, almost all of them were able to undergo further therapy at the time of the regrowth. So that outweighs some of the concerns of when you delay surgery in these patients.