Watch-and-wait strategy a good alternative for many rectal cancer patients

Last Updated: 2015-12-29

By Lorraine L. Janeczko

NEW YORK (Reuters Health) - For many patients with rectal cancer, the watch-and-wait strategy is safe and it's not inferior to radical surgery when patients develop a complete clinical response, according to new research.

"A substantial proportion of patients with rectal cancer managed by watch and wait avoided major surgery and averted permanent colostomy without loss of oncological safety at three years," the researchers report in an article online December 16 in the Lancet Oncology. "These findings should inform decision making at the outset of chemoradiotherapy."

"The watch-and-wait strategy may impact practice in rectal cancer for a significant proportion of patients who can avoid unnecessary surgery and unnecessary colostomy after a complete clinical response to chemoradiation -- quite a significant impact," Dr. Rodrigo Oliva Perez, of the Department of Gastroenterology at the University of Sao Paulo School of Medicine in Brazil, told Reuters Health by email.

"This information could revolutionize treatment of rectal cancer to truly personalize the treatment of the disease," added Dr. Perez, who wrote an invited commentary about the study.

In the OnCoRe study, lead author Dr. Andrew G. Renehan, of the Institute of Cancer Sciences of the University of Manchester, UK, and colleagues included patients of all ages diagnosed with rectal adenocarcinoma. Participants had no distant metastases and had received pre-operative chemoradiotherapy (45 Gy in 25 daily fractions along with fluoropyrimidine-based chemotherapy) between January 2011 and April 2013 at one academic cancer center.

Patients who had a complete clinical response were offered watch-and-wait management, and those who had an incomplete clinical response were offered surgical resection if they were eligible.

The authors also included patients with a complete clinical response managed by watch and wait between March 2005, and January 2015, at three neighboring regional cancer centers, whose details were obtained from a registry.

They derived one-to-one paired cohorts of watch-and-wait strategy versus surgical resection using propensity-score matching (including T stage, age, and performance status).

Of the 259 patients treated at the academic cancer center, 228 underwent surgical resection, and 31 had a clinical complete response and were managed by watch and wait. The authors also added 98 patients to the watch-and-wait group through the registry.

During a median follow-up of 33 months, of the 129 patients managed by the watch-and-wait approach, 44 (34%) had local regrowth, and 36 (88%) of 41 patients with nonmetastatic local regrowth were salvaged.

In the matched analyses, with 109 patients in each treatment group, the authors found no difference in three-year non-regrowth disease-free survival between watch and wait and surgical resection (88% with watch and wait vs 78% with surgical resection; p=0.043). And they found no difference in three-year overall survival (96% vs 87%; p=0.024).

In contrast, patients in the watch-and-wait group had significantly better three-year colostomy-free survival than did those who had surgical resection (74% vs 47%; hazard ratio 0.445; p<0.0001), with a 26% absolute difference in patients who avoided permanent colostomy at three years between treatment groups.

"Exactly who will respond completely to chemoradiation is still unpredictable," Dr. Perez pointed out in an email, and he joined the study authors in calling for further research.

The corresponding author was unavailable for comments.

The Bowel Disease Research Foundation funded this study. The authors reported no disclosures within this study.

SOURCE: http://bit.ly/1ZzPn4G and http://bit.ly/1PvAb41

Lancet Oncol 2015.