I will like to draw the attention to a recent review article by June Corry from Peter MacCallum highlighting some of the ways in which therapeutic ratio H&N cancer can be optimized further. One most intriguing hypothesis raised in the review based on the results of TROG 02.02 trial evaluating chemoradiation against chemoradiation + tirapazamine. There was almost a 20% improvement in Overall Survival with use of RT that adhered to the protocol. The author has raised an interesting point the Chemorad in some trials may be compensating for poor RT quality.
What are your thoughts on this issue? I for one know that poor RT results in a significantly poorer control having experienced it first hand as a part of my dissertation work.
A derivative issue is how is aggressive chemorad making these compliance issues worse?
I will like the opinion of the house in this regard and what are your views and methods to ensure good RT delivery to all / maximum patients that you follow (or will like to follow)?
the original trial that discovered this has been published and contains the indicators for 'adequate coverage'.
These indicators are actually easy to achieve AND exceed. What is not included is a description of what are acceptable volumes. The big centre response is "leave it to big centres" but that is its own problem. I have seen a 6 machine unit described as too 'small' to do H&N! The issue is that many centres have no choice about treating H&N and the focus should be on getting it right, not getting it sent off. Without going into details, the standard of H&N voluming is highly variable and this is very likely to impact on control.
I still haven't seen a good systematic guideline from PMCI or anywhere else that describes adequate voluming. Gregoire's guide is the closest.
Indeed Andrew you are right. In your case the variablity lies in voluming. In our country variablity will be existing even in portal selection and dose fractionation issues. I know centers where PTV is delienated directly using a manual brush and having been told by the "consultant" radiation oncologist in a private center that the machine generated PTV is going to be same. In government setups the situation is perhaps even more pathetic with centers existing which treat patients from one side on one day and other the other day; centers that rely on manual marking (how long back have you done that?).
It in this respect my question comes here - we are conducting newer trails using combinations of chemotherapeutic agents / targetted agents (common dissertation topics) without focussing on the most important issue - QA of basic RT. How do my colleagues in well established centers feel about this issue. In India we have a sister organization of our national association dealing with radiation oncology education for students. Even in there I have heard concepts like giving PTV margins of 2 cm in Head and Neck cancer IMRT !! In exams students are rarely asked about plan evaluation procedures but they are expected to know the latest molecular agent (that few people can actually afford in here). Do you think we should focus more on the radiation part in the curriculum rather than on the cemo part? I mean if a radiation oncologist fails to have a sound grounding in radiotherapy what good is other knowledge for him
Santam you have picked up a very volatile subject here. There are so many variables here, and i think its a check mate situation. If you tell andrew that we use Plaster of paris shells for immobilistaion, we re-use the Orfit masks made, we cut the orfit shells, we use Cobalt machines to treat Radical H & N RT pts, we use clinical planning at times to treat radical H & N pts, we draw a simple line on the patients neck when we decide to go off cord, etc i wonder what his comments wil be
It all sounds pretty ancient….but we have all done it and seen it.
Probably its the patient workload, and a million other reasons you can find for this practice.
But of course, we are trying to live in an ideal world, we are here to improve things and we are the future oncologists hence this discussion.
In the western world, you need to remember the foundation and basics here are pretty robust. All patients have brand new shells, they are all treated on Linear Accelerators, all have CT simulations, there is better man power with respect to patient number : oncologist : radiographer, this ratio is just right and adequate to run this show. Our waiting list is huge. Here they have Radical H & N pts as Category 1 patient (potentially curable)
The clinical trials conducted in RT for H & N cancers. Before they enrol a centre, they ask the treating oncologist to demonstrate their competence by asking them to mark tumour volumes and ask their physicist to plan that case.
This is verified by the prinicipal investigator and only if they are within tolerance of what is considered standard practice, that centre is enrolled. thats how multi-centre national clinical trials run. We all know interobserver variability and if you ask 10 oncologists to draw tumour volumes, there will be discrepancy in the volumes.
Its important to know the 95% CI and the tolerances in the deviation of this volumes.
You are absolutely right on the emphasis of plan evaluations in the exams, but those authorties who organise the curriculum do understand this importance and probably should be putting in more emphasis. These are things probably beyond the scope within the confines of Isocentre but certainly an important media for understanding its importance.
Rohit
Quality assurance, audits, never ending learning curve are all very important. There is a lot of difference in the way patient is evaluated and treated from center to center. I am Assistant Professor at a Government medical college, which has a cobalt machine and i am also a consultant at a private center with IGRT capability. I do skin markings, as well as contouring on almost a daily basis.
Daily set up, re markings, and ensuring reproducibility are always a constant challenge. It is a nightmare.
In the private set up almost all patients have thermoplastic mould made for them.
In the last few months i have had an intra parotid node failure in Ca tongue on contralateral side ( treated by IMRT), a level 5 node failure in Nasopharynx. To reconcile with one's inadequacies is difficult. I have tried to upload my contours but have failed , should have tried more.
Our effort should be to improve overall survival, loco regional survival. To be a good radiation oncologist, one needs to keep questioning oneself and learn the best practices, there may not be gold standard practice.
So QA and having some one to challenge you is a must. May be isocentre can work in this regard.
Regarding whether we need to put our head into chemotherapy and molecular therapy , or leave it totally to our colleagues Medical Oncologist, is a question i am struggling to answer. I will take some time before i can make my mind about it. But know for sure that the Medical oncologists are not uniformly trained in Head and neck or Cervix and have their own short comings.
manual marking (how long back have you done that?)
I have never done manual marking, only radiograph based mark up.
QA of basic RT
Absolutely! The issue is not the tools you have (unless you are the business owner, you have little control of this), the issue is what you do with your tools.
giving PTV margins of 2 cm in Head and Neck cancer IMRT !!
with those margins, you could just turn the machine on when the patient enters the bunker! The local failure rate should be a big ZERO!! like the saliva flow rate!
if a radiation oncologist fails to have a sound grounding in radiotherapy ….
this is a constant tension even here. The USA ROs are much better technically than we are, but often have to treat clinically hopeless cases radically. We claim that this is excessive. They claim that at least they do it technically better than us, which means the patients that we would treat are done better.
They have a point too. The aim should be to be clinically AND technically excellent. Stuffing some chemo in the vein can't overcome any technical deficiencies we might have. Here in lies the problem of the UK/SA 'clinical oncologist' - technical excellence in RO is a full time job.
i wonder what his comments wil be?
affording an Australian style radiotherapy service is not possible everywhere, you just have to do the best you can. The question here is whether Australian ROs are doing the best they can, that is whether we use our technology to its fullest. Personally I doubt it. Every Australian centre has the hardware and personnel to support IMRT, but most sites don't.
To reconcile with one's inadequacies is difficult
Personally I think the greatest requirement is for an attitude that looks to do better, even if it is skin markings to make them reproducible and matching best practice.
The issue of isolated failures in strange places is an interesting one. The benefit of increased conformality is better dose deposition in disease areas and tissue sparing. This will inevitably uncover disease patterns not previously seen because of the excessive dose splash of the field based techniques. Thankfully this is a rare occurrence. I constantly worry about my coverage when I see a recurrence. Fortunately (for me, not the patient) the recurrences have been in the middle of the original tumour. But I am also impressed by the new primaries in largely un-irradiated tissues.
having some one to challenge you is a must
the word competent has the meaning "able to compete". For that you need a competitor. In our professional area, our colleagues are competing for a standard of work, rather than competing for cases.
Andrew/Harsha/Rohit,
Good discussion for a post that was "mostly" a rant. But then I see what is happening in the name of RT training in my country and I don't know weather to cry or laugh. Interesting point about the patient workload part - in the study which the editorial is based on less patients = more protocol variations. So having less patients is never the answer. I am bringing the discussion on a new level here - in my department if chemotherapy was not practiced then there would have been no in patient admissions in the in patient at all. At any given time 80% patients are admitted for receiving chemotherapy or suffering from the myriad complications of CCT. Students know more about managing neutropenia rather than mucositis. Given the staffing pattern here I can safely say a medical oncology department can result far superior RT delivery in the department. And we are considered to one of the best RT departments in India (I know I am sounding boastful here). The question of having inadequate staffing doesn't really arise here as does mal-utilization of the available staff. Even in other centers and medical colleges colleagues have personally attested to the kind of training given with increasing emphasis on knowing the latest molecule rather than on the basic RT technique.
Coming to the point illustrated by Rohit - I have a idea of the excellent protocol development pursued by the international radiation oncology bodies. Having gone through the meticulously written protocols of RTOG I know people are more painstaking in their work there. Despite this protocol variations are known to occur as exemplified by this study itself having been conducted in a "westernized" setup.
Harsha u are right about setups being difficult but tell me how many people do you have working under you? We can see western centers failing to deliver "adequate" RT with the kind of resources they have - what the situation is in private centers (and the not so lucky govt centers) in India? For you as an experienced Rad Oncologist it is probably worthwhile to start working on integrating CCT in your practice given the dearth of trained medical oncologists in the country … but to emphasize that part of the training so much in the formative years is suicidal for the future generations IMHO.
Most of you have been trained here in India what do you think about your basic RT technique? People who have gone abroad after training in India do you feel you had to relearn the basic RT paradigm again? As the next generation we have a responsibility not towards ourselves but towards the patient that better training is imparted with the existing resources.
Finally as Andrew told in the last post we need a forum where we can "compete" with our professional colleagues. Can isocenter turn out to be that forum?
less patients = more protocol variations
I thought this was patient number issue was how many were put on the protocol, rather than how many were treated by the site or relevant doctor. In which case the issue might be ability to follow the protocol. Given that the protocol follows the thoughts of the PI and explanations can be confusing, these protocol violations might be reflections of the increasingly specific nature of protocols.
The presumption that follows is that places like the PMCI just give better treatment and that is not substantiated. I have worked at a coupled of very large centres, and the treatment was less conformal than at other units. There is a tautological sense that 'Big Unit = good treatment = Big Unit = good treatment … ad nauseum'. This only produces a sense of inferiority among the smaller unit.
It is the prerogative of the large unit to criticize the small - usually after the fact and usually after long periods of not providing any assistance. The Auckland H&N surgical team were an exception in my experience. They were supportive, they visited to educate, they didn't demand patients be sent, they offered opinions, if they thought you were good they said so and then used your expertise. I have seen what the large local units provide and frankly, what I do is not inferior. Possibly unintelligible to them, but not inferior. I have traveled extensively, and internationally, what I do is not inferior. We have been involved in international training and while we were criticised for not being hotter (all dose >98% but not enough 100%+), our conformality was regarded as best they had seen.