8th March 2018 - "Effect of Robotic-Assisted vs Conventional Laparoscopic Surgery on Risk of Conversion to Open Laparotomy Among Patients Undergoing Resection for Rectal Cancer"
Link to paper: https://jamanetwork.com/journals/jama/article-abstract/2658320?redirect=true
Daniel Lewis 07:03PM
Hi everyone, do you think start or give people enough 5/10 mins or so
Sacha Chiuta 07:05PM
Hello Dan, I think 5- 10 minutes would be good, some people are having trouble loading the website
Angus Hotchkies 07:06PM
Daniel Lewis 07:06PM
Sure thing, no problem
Daniel Ahari 07:15PM
Sorry, helping my friends logging in and encountering a lot of problems
Steve Seagal 07:16PM
Americos Argyriou 07:22PM
@daniel Ahari your friends still experiencing problems? I'm thinking that we should soon be making a start. Those of you who are here if you could introduce yourselves and include your email for PPD certificates that would be great.I'm Americos Argyriou, 2nd year.
Angus Hotchkies 07:23PM
Angus Hotchkies, 4th Year
Helena Law 07:23PM
I’m Helena Law, 2nd Year
Daniel Ahari 07:23PM
Daniel Ahari - Year 2
Sacha Chiuta 07:23PM
Sacha Chiuta, 2nd Year
Leo Hotchkies 07:23PM
Leo Hotchkies, 4th Year
Americos Argyriou 07:24PM
Dr Daniel Lewis will be facilitating our chat and helping us go through it. Thank you for being here, once again.
Daniel Lewis 07:24PM
No problem at all. What did everyone think of the paper?
Angus Hotchkies 07:25PM
Well-written paper, some interesting info about robotic surgery but didn't reveal anything significant and the study size could probably have been bigger I was thinking.
Americos Argyriou 07:26PM
I thought overall an interesting study, with quite a bit of significance in it's potential. Agreed didn't reveal much as results seemed quite matched in all areas
Sacha Chiuta 07:27PM
It was very interesting, specially the fact there were no major differences between the two groups
Daniel Lewis 07:27PM
Any thoughts on the journal it was published in - a very informative thing to look at
Angus Hotchkies 07:28PM
Not sure about the background, other than it's quite active and is American
Americos Argyriou 07:29PM
The study did have trials taking place in the States but other countries too and it's base was the UK from what I could tell... strange that the US believe it relevant to have it in JAMA
Daniel Lewis 07:29PM
So JAMA is huge, 2nd biggest impact factor of all medical journalsOnly the NEJM beats it, and it has a higher impact factor than either the Lancet or nature
Angus Hotchkies 07:30PM
Americos Argyriou 07:30PM
So significant weight behind this trial to be accepted there
Daniel Ahari 07:31PM
I was going to say the opposite regarding trial size, as I think you can always argue that the number of participants could be higher, but it did say that to date it's the largest trial of its kind with almost 500 participants. I'm not sure what the average is for studies comparing robots and humans, but a quick google for studies says it's usually less than 100. So yes while it would be nice to have more participants, context is important too I suppose
Leo Hotchkies 07:31PM
So what can we infer from the fact that JAMA chose to publish it? Can we comment on the reliability of the results/conclusions drawn?
Daniel Lewis 07:33PM
You all make a good point. It would be nice if the sample size was bigger especially as the authors acknowledge that their subgroups may have been statistically underpowered. But as Daniel says, to get close to 500 patients in a study comparing robotic surgery is far better than anything previousSo generally the big journals have a more rigorous peer review process, the study has to be pretty good to even get past the editor for somehwere lik ethe JAMAI say generally as some of you may remember this: http://www.thelancet.com/journals/lancet/article/PIIS0140-6736%2897%2911096-0/abstract
Daniel Ahari 07:35PM
Leo Hotchkies 07:35PM
I thought someone might bring that up as soon as I said that.
Sacha Chiuta 07:36PM
so building up on what Leo said, being published by JAMA adds to its credibility
Daniel Lewis 07:37PM
On the study size point, the authors did do a power analysis to determine the sample size they would need "The target sample size was 400 patients, which provides 80% power at the 5% (2-sided) level of significance to detect a reduction in the conversion rate from 25% in the conventional laparoscopic group to 12.5% in the robotic-assisted laparoscopic group, allowing for 16% attrition.13 The anticipated conversion rate in the conventional laparoscopic group was based on the MRC CLASICC Trial, which was the best available evidence at that time. The MRC CLASICC trial reported a conversion rate of 34% for conventional laparoscopic rectal cancer resection,21 which was reduced to 25% to account for advances in surgical technique"
To get a multicentre RCT like this past ethics commitees in various countries, the ethics committee would normally expect a power calculation
Angus Hotchkies 07:40PM
Fair enough, I remember going over power in a previous discussion, it was quite complicated!
Helena Law 07:40PM
Is this a study design that they have taken from elsewhere, or one that these authors have come up with themselves?
Americos Argyriou 07:43PM
I think the CLASICC Trial was looking to compare conventional with Laparoscopic assisted... so this is similar but comparing robotic vs laparoscopic and its measurement is conversion to open surgery
Daniel Lewis 07:44PM
Would you describe this as a gold standard study design?Or put another way. is there anything they could have done to improve the study design?
Americos Argyriou 07:46PM
The surgeones chosen had varying degrees of experience in the techniques.. they set a 30 operation minimum as incl criteria which is basically nothing*surgeonswhich definitely affects the results as laparoscopic has been around for alot longer than robotic-assisted
Sacha Chiuta 07:47PM
The follow up time period could have been longer to see if more complications would arise in patients
Angus Hotchkies 07:48PM
The "experts" in robotics I'm assuming will likely have less experience/procedures than the "expert" lap surgeons but at this time I don't see how that can be avoidedAnd they can't have blinded the trial so it seems like a pretty rigorous design
Daniel Lewis 07:48PM
Good point Americos and Angus, and they say that the surgeons included did have less experience on robotics "On average, patients received an operation performed by a surgeon with experience of a median 91 (interquartile range, 45-180) previous conventional laparoscopic operations and a median 50 (interquartile range, 30-101) previous robotic-assisted laparoscopic operations"Good point on the FU period Sacha. Could they have blinded the participants?
Daniel Ahari 07:50PM
Is it even possible to blind the participants?
Sacha Chiuta 07:50PM
I agree with Dan would it be possible
Daniel Ahari 07:51PM
Wouldn't that be unethical
Leo Hotchkies 07:51PM
I think it is possible and an argument can be made they could
Sacha Chiuta 07:51PM
regarding gaining consent and explaining procedures to patients etc.
Daniel Lewis 07:51PM
Not necessarily because you dont currently know which treatment is superiorHence the purpose of the study
Leo Hotchkies 07:52PM
So would approval for a blinded study be made easier by this paper if another trial was to go ahead in the future?
Daniel Lewis 07:53PM
So usually the problem with blinding in surgical studies is that the patient knows whether they have had an operation or not but I'm not sure in this case whether the incision size would be the same for both, the details aren't clear
Sacha Chiuta 07:53PM
If the trial could have been blinded I think the trial size would definitely have been bigger, because some patients dropped out because they preferred the other method of surgery than the one they were assigned to
Daniel Lewis 07:53PM
I suspect part of the reason for not blinding the study is that the robotic procedure is more expensive - so patients in the US, S korea etc had to aggeee to pay for itagree*
Sacha Chiuta 07:53PM
A bigger trial size would have yielded even more reliable results
Daniel Ahari 07:54PM
Well regardless I think we can agree that a double-blind trial would have been impossible...
Angus Hotchkies 07:54PM
Yeah that's very true
Americos Argyriou 07:54PM
The point you just stated Dr Lewis is a potential beneficial outcome and a vested interest people might have had in this study
Helena Law 07:54PM
Perhaps the difference in expense could have affected patient-reported outcomes
Daniel Lewis 07:55PM
That is a good point, there is another issue with the patient reported outcomes as wellDid all the patients report their post-op outcomeon the point before- just read the supplementray methods - "As the two surgical procedures create incisions which can allow the patient to be blinded to the operative procedure performed, it would be preferable scientifically to blind patients to their surgical procedure, particularly in respect of patient-reported outcomes. However, it is anticipated that in practice maintaining the blind would be extremely problematic (e.g. in countries such as the USA where private healthcare insurance companies require disclosure of surgery details). Furthermore, patients will also be seen by many healthcare professionals throughout their time in the trial, increasing the risk that the blind may be broken. As a consequence, the trial design will not involve blinding patients to the operative procedure. It should be noted that the trial endpoints are mainly objective measures and a central blinded assessment of these measures is included where possible (e.g. blinded central assessment of the quality of the plane of surgery; evaluation of intra-operative laparoscopic skills (GOALS))."
Angus Hotchkies 07:57PM
Well they've been thorough!
Leo Hotchkies 07:58PM
Also to note: "All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Drs Jayne, Pigazzi, Rautio, Thomassen, and Bianchi and Mr Gudgeon reported serving as proctors for Intuitive Surgical Inc. Dr Pigazzi reported serving as a consultant for Intuitive Surgical Inc. Mr Gudgeon reported receiving travel expenses from Intuitive Surgical Inc. No other disclosures were reported."Intuitive Surgical Inc. are the makers of the Da Vinci system
Americos Argyriou 07:58PM
regarding assessment of the quality of surgery.. Does that not mean a surgeon might want to avoid operating on tough cases to protect his figures as all their operations will be masde public?And Leo I saw that too! Interesting...
Daniel Ahari 07:59PM
Do RCT cases affect their "figures"?
Americos Argyriou 07:59PM
Daniel Ahari 07:59PM
If so, then you definitely have a point
Daniel Lewis 08:00PM
I think that would depend on the country they are operating in and the standard for reporting 30 day mortality etc. Do we have any other concerns about the patient reported data?
Daniel Ahari 08:01PM
They're subjective measures"The I-PSS17 is a standardized, patient self-reported measure of the subjective problems that the patient experiences with urinating, with scores ranging from 0 to 35 "Anything that uses a subjective self report should be taken with a grain of salt, standardised or not
Helena Law 08:04PM
Patient reported data regarding sexual function was very low (56.6% in men and 35.8% in women) - thus making it difficult to make a conclusion on the extent that this was affected by laparoscopic vs robotic surgery
Daniel Ahari 08:04PM
Although I suppose it's hard to measure their parameters (bladder and sexual function) objectively
Americos Argyriou 08:05PM
different cultures might have different expectations or beliefs about their symptoms.. which might affect how they judge their parameters
Daniel Lewis 08:06PM
You all make good points. The major concern though is the low reporting rate at 6 months. 35.8% is pretty poor, especially as this is a likely very expensive RCTHaving worked with patient reported data before, the major issue with incomplete datasets is that the people who respond are either very pleased or pissed off with the outcome- so you miss the middle ground
Helena Law 08:10PM
That is a good point - to improve for the future, are there any incentives that the authors could give patients in order to complete the dataset, without bias?
Daniel Lewis 08:11PM
So where I work, for the spine Tango study they have specailist nurse who ring up patients post op and remind them to fill out the questionnaire.
Sacha Chiuta 08:12PM
How successful has that been?Do more people respond when they are reminded?
Daniel Lewis 08:12PM
70% plus response rate at 1yr
Daniel Ahari 08:13PM
As opposed to what % beforehand?
Daniel Lewis 08:13PM
Good question, difficult to say as I think from that start that system has been in placeWould this paper change anyone's management?
Daniel Ahari 08:14PM
I suppose 70% is still nothing to scoff at regardless
Angus Hotchkies 08:14PM
It might make people think twice about using robotics considering the cost
Daniel Ahari 08:15PM
The nature of the questions are quite invasive and private though, I would imagine that might affect the number of responses
Americos Argyriou 08:16PM
I believe the subgroups were too small to make any meaningful impact, otherwise we might have been able to get a significant difference in results in certain operation or patient typesSo perhaps robotic might be more appropriate for a certain subtype of CRC
Helena Law 08:17PM
Also since the surgeons tend to be more experienced in laparoscopic surgery, it will be unlikely for patients to choose robotics at this moment in time, taking into account the extra costs involved
Daniel Ahari 08:18PM
In the grand scheme of things though, it won't discourage future trials and innovations, which can only be good - robotics can only get better
Americos Argyriou 08:18PM
true Helena. I doubt any surgeon would let their patients know of their experience though!
Daniel Lewis 08:20PM
All valid points, for me the main take home message from this paper is that robotic surgery is as safe as laparoscopic surgery. Given the experience gap between laproscopic an robotic surgery for the surgeons in the study, it's difficult to say whether robotic surgery would be better with more user experience
Americos Argyriou 08:21PM
Dr Lewis do you believe that laparoscopic surgery has peaked in terms of how good it's results can get? As we know Robotics will only get better with time
Angus Hotchkies 08:22PM
Yeah, really interesting paper overall and lots of points to take away
Daniel Lewis 08:22PM
So colorectal surgery is not my area, but I think if a surgeon feels more comfortable using a robot and can tell the patient that it is currently equivalent to laparoscopic surgery then cost aside the patient may still opt for it
Angus Hotchkies 08:23PM
Sorry all, I need to go now but see you all soon Thanks Dr. Lewis and thanks for organising Americos
Daniel Ahari 08:23PM
I have to go as well sorry, thank you though, I'll come to the next one
Daniel Lewis 08:24PM
Thank you for your contributions.
Americos Argyriou 08:24PM
That's alright guys, I believe we are coming to an end for this session as it is.
Sacha Chiuta 08:24PM
Thank you to everyone in attendance, and thank you Dr Lewis for facilitating.
Americos Argyriou 08:24PM
Dr Lewis, any final points or issues you noticed?
Daniel Lewis 08:25PM
No i think we covered most of the salient points, I think we can all rest easier knowing that the robots wont be taking our jobs just yet!
Americos Argyriou 08:26PM
Thank you everyone for attending, and Dr Lewis for chairing the session.
Leo Hotchkies 08:26PM
Thank you for organising this event and for facilitating Dr Lewis - some good points to remember
Helena Law 08:27PM
Thank you all, especially Dr Lewis - it was been a very enlightening session, especially the aspect about JAMA’s influence in the research community
Daniel Lewis 08:30PM
See you all at the next one, bye for now