Rapid Responses to:
|
|
Rapid Responses: Rapid Responses published:
-
![[Read Rapid Response]](/icons/misc/sectionDOWN.gif)
KTP laser prostatectomy cost effectiveness
- Ranjan Thilagarajah, Khurshid Ghani (18 May 2009)
-
1.8 million do not have prostate cancer in the UK
- Peter Kirkbride (18 May 2009)
-
Re: 1.8 million do not have prostate cancer in the UK
- Robert Pickard (20 May 2009)
-
Re: KTP laser prostatectomy cost effectiveness
- Robert Pickard (20 May 2009)
-
Surgical treatments for men with benign prostatic enlargement: cost effectiveness study or a costly ineffective study
- Said F Mishriki (21 May 2009)
-
Re: Surgical treatments for men with benign prostatic enlargement: cost effectiveness study or a costly ineffective study
- Robert Pickard (26 May 2009)
-
The study is flawed
- Said Fadel Mishriki (2 June 2009)
-
Re: The study is flawed
- Robert Pickard, Nigel Armstrong, James N'Dow (6 June 2009)
|
|
|||
|
Ranjan Thilagarajah, Clinical Lead in Urology CM1 7ET, Khurshid Ghani
Send response to journal:
|
The finding that potassium titanyl phophate (KTP) laser vaporisation is not cost effective in this study appears to be incorrectly based on data grouped from a number of diathermy vaporisation techniques. The previous systematic review quoted in the paper also groups together therapies including Nd:YAG and interstitial lasers which cannot be used to assess the efficacy of KTP vaporisation(1). The single eligible trial comparing KTP with conventional transurethral resection of prostate (TURP) is also too small to form an opinion concerning the effectiveness of KTP in this setting(2). It is unfortunate that the diathermy vaporisation treatment strategy group did not allow for a second treatment in case of initial failure, as this may have altered the cost effectiveness score of this treatment when compared with other combinations. The cost effectiveness of KTP relies on specialist centres carrying out large numbers of procedures with protocol driven patient care pathways in place. It remains difficult to recruit patients to randomised studies (with TURP) as a result of the known complications associated with the latter. It must also be recognised that these technologies are being developed and improved at a rapid rate and it is welcomed that the authors recognise the uncertainties and limitations of the published study in view of this. The authors’ proposal of longer term “tracker” trials will go some way towards producing meaningful data for the management of benign prostatic elargement. 1 Lourenco T, Pickard R, Vale L, Grant A, Fraser C, MacLennan G et al. Alternative approaches to endoscopic ablation for benign enlargement of the prostate: systematic review of randomised controlled trials. BMJ 2008;337:a449 2 Horasanli K, Silay MS, Altay B, Tanriverdi O, Sarica K, Miroglu C. Photoselective potassium titanyl phosphate (KTP) laser vaporization versus transurethral resection of the prostate for prostates larger than 70 ml: a short-term prospective randomized trial. Urology 2008;71:247-51 Competing interests: None declared |
|||
|
|
|||
|
Peter Kirkbride, Consultant Oncologist Weston Park Hospital, Sheffield S10 2 SJ
Send response to journal:
|
Oh dear, BMJ. You have taken the factually correct statement in the introduction to this article; 'there are 1.8 million cases (of BPE) in the UK', and changed it into a '1.8 million cases of prostate cancer' headline in your 'The Week in Numbers' feature at the front of the print version! Competing interests: None declared |
|||
|
|
|||
|
Robert Pickard, Senior Lecturer Newcastle University, NE2 4HH
Send response to journal:
|
I too noticed this slip up. Happily one for the Editor rather than Author. Competing interests: None declared |
|||
|
|
|||
|
Robert Pickard, Senior Lecturer Newcastle University, NE2 4HH
Send response to journal:
|
We thank Drs Thilagarajah and Ghani for studying our paper and making some pertinent points. We used the highest quality data available for defining parameters used in the model. We agree that evidence gaps concerning KTP laser vaporisation increased the degree of uncertainty regarding these parameters but additional sensitivity analyses using wide ranges of parameter values did not change our findings, thus supporting our conclusions. Concerning repeat vaporisation procedures we were unable to find any evidence that would allow us to predict the likelihood of successful outcome. The expert group considered that a repeat procedure following failure to respond or relapse would not, at present, be considered as standard management and therefore made the decision not to include such strategies in the model. We completely agree that further high quality trials are needed, particularly using current vaporisation techniques and 'tracker' methodology does allow for changes in technology during the trial period. We consider that TURP remains the standard comparator and a number of recent trials have indeed been successfully conducted with TURP arms. The use of vaporisation techniques has however expanded the use of bladder outlet surgery for men with severe co-morbidity or anticoagulant treatment that precludes TURP and therefore stratified randomisation may also be required. Whilst we acknowledge the uncertainties regarding the evidence base, KTP laser vaporisation cannot be considered cost-effective in our model since it is less effective and more costly than alternative ablative options. Competing interests: None declared |
|||
|
|
|||
|
Said F Mishriki, Consultant Urological Surgeon Aberdeen Royal Infirmary, Foresterhill, Aberdeen AB25 2ZN
Send response to journal:
|
I am astounded that this study was published in the BMJ [1]. The
authors admitted that selection between techniques was difficult. Their
assumption that these have the same tissue ablation effect is based on no
evidence. The definition of failure as <10% improvement in symptoms is
at best flawed. Clinical effectiveness data were derived from a
systematic review that had its own limitations [2,3]. The conclusion that
initial vaporisation followed by holmium laser enucleation for failure or
relapse might be advantageous both to patients and healthcare providers is
bizarre. For starters, tissue vaporisation is an almost obsolete
technique. We do not need a Markov model or a Monte Carlo simulation to
conclude that this was a costly ineffective study.
References: 1. BMJ 2009;338:b1288 2. Lourenco T, Pickard R, Vale L, Grant A, Fraser C, MacLennan G, et al. Minimally invasive treatments for benign prostatic enlargement: systematic review of randomised controlled trials. BMJ 2008;337:a1662. 3. Lourenco T, Pickard R, Vale L, Grant A, Fraser C, MacLennan G et al. Alternative approaches to endoscopic ablation for benign enlargement of the prostate: systematic review of randomised controlled trials. BMJ 2008;337:a449. |
|||
|
|
|||
|
Robert Pickard, Senior Lecturer Newcastle University, NE2 4HH
Send response to journal:
|
We thank Mr Mishriki for his interest in our study. The editorial team at BMJ accepted the study following revision subsequent to the comments of clinical and health economic expert referees. The great variety of techniques trialled for the ablation of benign prostatic enlargement did indeed require a degree of conceptual grouping in order to enable construction of a useful and workable model. Whilst we respect Mr Mishriki's views we would contend that the final effect of all technologies is to heat prostatic tissue sufficiently to cause cell death. The temperature reached will determine whether this causes coagulation or vaporisation and instrument design will determine whether vaporised tissue is removed as small particle effluent, piecemeal, or as a complete adenoma. Given this common basis we felt the treatment groupings to be reasonable. The definition of failure was set at the minimum change in symptom score appreciable by an individual undergoing treatment. We agree that systematic review and meta-analysis of randomised studies has limitations but it remains the best technique to summarise evidence regarded as of high quality. The easiest way to improve its scope is to perform more quality trials and ensure that they are reported consistently. We acknowledge that the diathermy method of vaporisation is little used at present, despite a high level of evidence for its effectiveness, although use of bipolar energy delivery may lead to its resurgence. We would contend that currently popular vaporisation techniques must at least equal diathermy in effectiveness and cost to make a change in practice worthwhile to patients and the NHS. We are sorry that Mr Mishriki felt our work to be costly and ineffective but we are encouraged that it provoked this debate. Competing interests: None declared |
|||
|
|
|||
|
Said Fadel Mishriki, Consultant Urological Surgeon Aberdeen Royal Hospitals, Foresterhill, Aberdeen AB25 2ZN
Send response to journal:
|
The authors in the cost effectiveness study made several assumptions (1). I have stated some in a previous response. The authors identified transurethral microwave thermotherapy (TUMT) and diathermy vaporisation (TUVP) as typifying the minimally invasive and tissue ablative groups, respectively. Both treatment modalities are very uncommonly used in modern practice. The authors based their appraisal regarding the effectiveness of treatment on two systematic reviews (2, 3). These systematic reviews had set the primary outcome measure as the change in symptom score at 12 months after surgery. The follow-up is too short to be meaningful (4). The rules that the authors designed “minimally invasive treatments could be repeated only once; tissue ablative and holmium laser enucleation procedures could not be repeated because of the effect on remaining prostate tissue and near total removal, respectively” are most unusual indeed. The treatment strategies (table 1 in the article) are at best illogical. In addition, setting the cycle length “three months, the period over which benefit would occur and short term adverse events resolve” is incorrect. It often takes a much longer period for a final outcome. Incontinence bad enough for the person to seek help resulting in additional treatment is the only complication included in the model. However, urethral strictures (2.2-9.8%) and bladder neck contractures (0.3-9.2%) are late complications that require re-treatment (5). The authors acknowledged that long term data were available only for transurethral resection and microwave thermotherapy. Deriving relapse rates for other treatments according to the weighted mean difference in symptom score at 12 months is open to question. If the study design is flawed, the conclusions are unsound. The suggestion that “initial diathermy vaporisation followed by either holmium laser enucleation or transurethral resection, repeated if necessary on failure or relapse, are cost effective strategies for surgical treatment of symptoms” is bizarre. The major issue when an a study like this is printed in the BMJ is that it will get quoted by the less informed in months and years to come. This is precarious. References: 1. Armstrong N, Vale L, Deverill M, Nabi G, McClinton S, N’Dow J, Pickard R, for the BPE Study Group. Surgical treatments for men with benign prostatic enlargement: cost effectiveness study. BMJ 2009; 338: b1288 2. Lourenco T, Pickard R, Vale L, Grant A, Fraser C, MacLennan G, et al. Minimally invasive treatments for benign prostatic enlargement: systematic review of randomised controlled trials. BMJ 2008;337:a1662 3. Lourenco T, Pickard R, Vale L, Grant A, Fraser C, MacLennan G et al. Alternative approaches to endoscopic ablation for benign enlargement of the prostate: systematic review of randomised controlled trials. BMJ 2008;337:a449 4. Elliott SP. Endoscopic ablation for benign enlargement of the prostate. Newer techniques are no better than transurethral resection, but the evidence base is poor. BMJ 2008;337: a535 5. Rassweiler J, Teber D, Kuntz R, Hofmann R. Complications of transurethral resection of the prostate (TURP)--incidence, management, and prevention. Eur Urol. 2006 ; 50: 969-79; discussion 980. Competing interests: None declared |
|||
|
|
|||
|
Robert Pickard, Senior Lecturer Newcastle University, NE2 4HH, Nigel Armstrong, James N'Dow
Send response to journal:
|
Whilst we thank Dr Mishriki for his interest and further comments on our paper, we cannot agree with his opinions regarding dealing with uncertainty in health economic analysis. Our study was carried out according to current best practice in systematic review, meta-analysis and economic modelling and has been subjected to extensive and thorough peer review. All of the concerns expressed by Dr Mishriki are addressed within the paper and are covered by appropriate sensitivity analyses including relapse rate, use of a life-time time horizon, and accounting for adverse event rates. In addition the text advises cautious interpretation of the results due to uncertainty created by gaps in the required evidence. Whilst we do not expect every reader to agree with all of the assumptions required for the Markov model or indeed our conclusions, some of Dr Mishriki’s comments suggest a lack of understanding of research methodology presented in our work. There would seem to be little or no worth in pursuing further dialogue with Dr Mishriki and the authors are content to respectfully acknowledge the expressed opinions but not to debate them further. Competing interests: None declared |
|||