Cordotomy in mesothelioma- related pain: a systematic review CASP Analysis Emma Lowe

Did the review address a clearly focused question?

Clearly set out PICO P – Patients with mesothelioma where the intension was to perform cordotomy I – Cordotomy C – Treatment for pain using other modalities O – Effectiveness of pain relief and side effects

Did the authors look for the appropriate sort of papers?

Excluded reviews and single case reports 9 papers included All included papers all seem relevant All studies were case series – lowest form of evidence – reflects the poor quality of evidence available

Do you think the important, relevant studies were included?

Search strategy designed for sensitivity not specificity. Basically searched for every trial about cordotomy and then manually reviewed (2385 to 9!) 14 databases Reviewed reference lists from included studies and previous reviews No limits on language, year of publication or publication status Nil specific about contacting trialists although they did get some unpublished data (one was an author, one is a consultant in Warwick)

Did the review’s authors do enough to assess the quality of the included studies?

All had 1 or more limitation – loss to follow up of >10%, non-consecutive, reterospective, more than 20 years old, <10 patients. Acknowledge that all low in the hierarchy of evidence. Mention that 3 of the studies were single author studies - ?less generalisable and reliable Table

If the results of the review have been combined, was it reasonable to do so?

Attempted to combine a lot of information No one bit of information available across all studies. Different time scales where pain was measured Different reporting methods. Grouped pain into complete, partial or poor pain relief for 6 studies. Meta-analysis – One calculated as a random-effects model and one as a fixed-effect model (not clear why) Account for the heterogeneity due to 2 small studies. No one table presents all the results (likely as so varied).

What are the overall result of the reviews?

What are the overall result of the reviews? 1 All 9 studies demonstrated good pain relief in the majority of patients – In patients where cordotomy was intended there was complete pain relief in % (75%) – In patients where cordotomy was performed there was complete pain relief in % (83%) – Analgesia use appeared reduced (less specific information)

What are the overall result of the reviews? 2 Initial effect was the greatest. This reduced over time but never to pre-procedure levels Other outcomes also showed beneficial effect (increased performance status, sleep, patient satisfaction) Range of adverse events, most of which were transient. Deaths all attributed to disease progression rather than procedure.

How precise are the results?

Intended cordotomy 95% CI 52-89% Performed cordotomy 95% CI 72-90% Other data unable to be assimilated and came from small number of studies or different information.

Can the results be applied to the local population?

Mesothelioma patients likely to receive palliative care. Not all patients who have cordotomy have mesothelioma. Data from other patients excluded ?are they planning on a separate review to look at this. Minimal consideration by authors to generalisability No clear indication of when cordotomy was considered. Minimal information about participants in the studies (mainly men, large range of ages, most patients on multiple analgesia. Post procedure survival confusing (227-36,527 days, although individual patients died sooner in some studies)

Were all important outcomes considered?

Seem to have looked at a reasonable amount. No-one looked at function or ADLs All seem to have looked at pain, adverse events and 1 other things with minimal consistency.

Are the benefits worth the harms and costs?

Not addressed by the reviewers. No economic evaluation or even estimate of the costs. Presumably relatively expensive treatment with intensive training needed for treatment of a small number of individuals. However, useful treatment for patients with ‘intractable’ pain. More research needed, although also some ideas about how to do this.

The End