In a series of interviews, we will be previewing this year’s 15th International Colorectal Meeting in Turin, 16-18 April. We talked to Dr Rodrigo Oliva Perez from the Instituto Angelita & Joaquim Gama and the Ludwig Institute for Cancer Research, São Paulo, Brazil, about the ‘watch and wait’ approach for treating rectal cancer.
“The premise behind the ‘watch and wait’ approach is: first, do no harm,” explained Dr Perez. “We have challenged the dogma that we should always resect it even if there is no residual cancer after neoadjuvant chemoradiotherapy (nCRT), particularly in the setting of evidence of clinical and radiological complete tumour regression.”
He added the ‘watch and wait’ approach has many advantages provided oncological outcomes are similar. This approach avoids immediate post-operative morbidity and mortality. In addition, this approach means that a temporary or definitive stoma is not required and the urinary and sexual consequences of surgery are also avoided, along with possibility of terrible anorectal function.
“Even though many of these issues may worsen over time and also as a consequence of CRT alone, there is no question that head-to-head comparison between surgery and no-surgery will favour no surgery,” he said. “However, with the watch and wait approach there a considerable risk for local recurrence. Even though experience has shown that these are amenable to surgical salvage with no negative impact of survival, it may give the ‘false’ impression that surgery would have prevented this. Of course, the anxiety of not knowing the definitive answer to whether this was a complete response or not until follow-up proves you one way or the other is a potential disadvantage, as is the requirement for intensive follow-up.”
Although there are no current guidelines available for ‘watch and wait’ in rectal cancer management so far, he believes that the body of evidence available will soon be considered to sufficient to include this treatment alternative in the international guidelines.
Dr Perez explained that he is currently involved in the International Watch and Wait Database (IWWD) under the auspices of European Registry of Cancer Care (EURECCA), based in Leiden, the Netherlands. The database is currently collecting data from multiple centres and has already gathered data from >1000 patients with a complete response after 12 weeks of chemotherapy and/or radiotherapy for rectal cancer.
“Some patients respond very well to the chemo- and/or radiotherapy and there is no sign of tumour after the treatment,” he added. “We observe and wait as an alternative to surgery and this ‘Watch and Wait’ treatment has shown promising results.”
He emphasised that further research of the long-term effects of omitting surgery (‘watch and wait) after complete response is necessary and participation in long term prospective observational studies, such as the IWWD, will contribute to the understanding of this new treatment option.
“An important area of interest is the possibility of prediction of tumour response by molecular biology. Pre-treatment biopsy samples will potentially allow us to understand and identify patients that have sensitive or resistant tumours to nCRT,” he concluded. “This will allow better selection of patients-candidates to this approach. Also, liquid biopsies will probably allow us to monitor and identify complete responders in an objective and highly-specific way in the near future. During my presentation in Turin, I will share some of the current research and some of our preliminary results, regarding both of these strategies.”