In the previous article on this site I wrote about recent work that showed that the use of a cheap, safe and generally available anti-inflammatory pain killer (ketorolac) had the potential to massively reduce the incidence of cancer relapse following surgery. This extraordinary result was discovered by a Belgian anaesthesiologist Dr Patric Forget and colleagues. Now working on a clinical trial to put this finding under test, Dr Forget kindly agreed to respond to a short interview to give us more of background to his research.
PP: What prompted your initial investigations - did you expect to find the results that you found?
PF: The diverse long term effects of anaesthetic techniques and analgesic medications have been suspected for many years. Discrepancies exist about the effect on outcome in humans. Concerning opioids, many data exist, but results are inconsistent. Concerning NSAIDs, animal data are consistent, but no human data are available. Therefore, we investigated it in the prospective patients listing existing in our Cancer Centre. Nevertheless, the magnitude and the repetition of the NSAIDs data were relatively unexpected.
PP: What are the clinical factors that influence the choice of ketorolac versus other medications?
PF: The anaesthesiologists have to make choices for which there are not always evidence-based guidelines. This is the case with single NSAIDs dose in the perioperative period. The usefulness of this single dose in terms of analgesia improvement is still matter of debate. The American Society of Anesthesiology has no definitive recommendations about it. Consequently, in many centres, including ours, some anaesthesiologists use it systematically, and others not.
PP: Your findings suggest that other interventions - such as taking a surgical biopsy - could also have a negative influence on cancer outcomes. What is your view on this?
PF: Inflammatory pathways are implicated in the development of cancer. It is probable that the degree of tissue injury during surgery is associated with cancer outcome. Nevertheless, whether this effect is mediated by an influence on tumours cells, tumours cells spreading and/or immune suppression is not clear. In all cases, many arguments exist to limit as far as possible the extent of tissue attrition and surgical procedures in cancer patients.
PP: Although the emphasis of your work is on breast cancer, there is evidence that a similar bimodal pattern of relapse occurs in other cancers. Do you think that peri-operative ketorolac can have a similar reduction in relapse in these cancers?
PF: Yes. We have done the same observation in non-small cell lung cancer (NSCLC) (Forget et al, Ann Surg Oncol 2013). In NSCLC, the bimodal pattern of relapse was shown by Demicheli et al. Out data shows that the NSAIDs effect is also present. In contrast, in prostate cancer, no NSAIDs effect was observed (Forget et al, Eur J Anaesthesiol 2011). Concommitantly, no bimodal patter of relapse was shown, in my knowledge, arguing for a different pre-, intra- and/or postoperative cancer pathophysiology.