Have the final results of the OPERA trial changed the way you approach organ preservation in rectal cancer?

Great question. The OPERA results were certainly promising with 3-year organ preservation rates at 97% for tumors less than 3 centimeters. Patients neither received TME nor doublet chemotherapy (no oxaliplatin). Importantly, it was also the first randomized trial showing a higher dose of radiotherapy (with the addition of brachytherapy) led to higher rates of organ preservation. Overall, a great study.

Some considerations:

1. These were small tumors, max dimension allowed on the study was 5 cm, and mostly (65%) T2. So, more an early-stage population, not locally advanced although included T3 and N1 (but nodes had to be <8 mm).
   • Underscoring this point, the organ preservation rate for chemoRT (no brachy boost) was 59% at 3 years – quite high.
...

We will undoubtedly begin to develop this treatment further at our center. Centers in the US do not specialize in endorectal contact therapy the way that France in particular has for many decades. The OPERA trial is the climax of work started by Jean Pappion in the 1960s, continued by Prof Gerard in Lyon, and expanded to more centers in France and the UK. The practice is very regionalized. Probably a similar model would be necessary to achieve expertise in the US the way it has in Europe. The evidence is quite compelling and this will undoubtedly stimulate centers to start programs in an effort to increase the pool of patients that are eligible for non-operative management. In addition to endocavitary therapy, with either low energy x-rays ...

The 2022 ASCO abstract is a great jumping-off point, but reviewing the final publication will be essential before making any decisions about changes in practice. Let's re-engage when it is published!

May 4, 2023:
We're back! Final results are available: Gerard et al., PMID 36801007

With this update, we need to have a conversation in this specialty about utilizing this excellent treatment option. In a nation that considers itself world-class in terms of cancer care, there are too many excuses for why we can't offer this option to patients and why we have not studied this further in America. The study utilized contact brachytherapy and as @Dr. First Last has explained to me - the surface dose rapidly dissipates (dose is about 10% 1cm in) and so this is not going to work for bulky tumors - the current data from OPERA is for non-bulky and small tumors. But, it does work very well for these. As far as bulky tumors, HDR would allow for higher doses for bulkier tumors, but there is limited and not very much prospective data....