Friday, July 21, 2006
Forgive me as I wallow in a bit of therapeutic nihilism before the weekend with regard to nutrition-related interventions in cancer care...
1) Per a recent blog topic--interventions for cancer anorexia-cachexia--the most recent Journal of Clinical Oncology presents two randomized, double-blind, placebo controlled trials of interventions for this. One compared 6 weeks of treatment with a cannabis extract vs THC (marinol) vs placebo and found essentially no differences between groups regarding appetite, quality of life, or adverse effects. There were lots of drop outs (~240 subjects randomized; 169 completed) and the THC dose was on the lower side ( 2.5mg twice a day) but the results nevertheless were completely underwhelming. The other trial looked at ~500 patients given eicosapentaenoic acid or placebo for 8 weeks and again found no significant improvements in the treatment arm. (Eicosapentaenoic acid is a type of purified fish oil extract.) These were some of the largest studies of their kind for cancer cachexia and these results are disappointing but not, unfortunately, surprising.
The recent Journal of the National Cancer Institute contains a metaanalysis of trials looking at nutritional interventions and cancer outcomes . The analysis tries to contain an unwieldy number of trials looking at extremely heterogeneous data (different patient populations such as cancer vs pre-cancerous lesions, different outcome measures, and different nutritional interventions) and is limited by a distinct lack of quality trials. The authors conclude, rather succinctly, "There is no evidence that dietary modification by cancer patients improves survival and benefits disease prognosis." A related editorial is included. I am sure I'm not the only palliative care provider around who constantly tries to answer questions from my cancer patients about "What should I eat?" In most circumstances I try to encourage my patients to eat whatever they damn well please acknowledging that I have no knowledge of any particular diet benefiting them so they might as well eat what they like. I am constantly surprised, although I shouldn't be, by how frequently patients find this response dissatisfying, as if there should be some answer, some diet, that will help them to live longer or better. Part of it may of course be the patient 'picking up' on my own sense of therapeutic nihilism in this area, and I have not yet I guess developed a way of recommending ice cream, pot roast, and cola without sounding... dismissive is the only word I can think of here...even after empathetically acknowledging how frustrating and frightening it can be to see oneself losing one's appetite, weight, and 'battle' against cancer.