Hi. I am David Kerr, Professor of Cancer Medicine at the University of Oxford. Something that has always troubled me is how we deal with home parenteral nutrition in patients with advanced cancer, who are often cachectic and can't eat because of their gastrointestinal obstructions.
It is a problem that is often defined culturally. Many different factors influence how we eat and how we take in energy. Whether in the well individual or in patients with cancer, cultural, religious, economic, and food preference (eg, vegetarianism) factors influence how a person eats. It is a socially and culturally complicated issue.
There is an ethical and moral dimension to this, as well. The argument goes a bit like this: If you have patients with advanced cancer who have obstructed gastrointestinal tracts, then these patients are going to die in a couple of months despite using parenteral nutrition. Therefore, why risk the discomfort? Why risk the expense? It is not a cost-effective intervention.
On the other hand, you could argue equally well that by denying these patients food, we are starving them. We are abbreviating their lives. If you take a healthy individual and deprive that person of all caloric intake, then that person will die of starvation in about 2-2.5 months. If you have a patient whose prognosis is longer than that, then I have no doubt that by not offering parenteral nutrition, we might possibly abbreviate that life.
This is hugely controversial. If you look at the use of home parenteral nutrition in the United Kingdom, less than 5% of the appropriate patients receive it, compared with Italy, where some 60% receive it. In a recent survey, most other European countries were somewhere in between. We have no clear guidelines, no strong evidence, and no prospect of randomized controlled trials. I can't imagine that nutritionists would feel at all ethically comfortable with that.
So, congratulations to Dr. Bozzetti and the international group of colleagues[1] who conducted a very detailed and thoughtful prospective study of 414 cachectic cancer patients with gastrointestinal obstruction. These investigators did some very detailed multivariant modeling to try to understand the prognostic factors that might define the subgroup of patients who will have longer survival and a better prognosis, and therefore who at least rationally might derive some benefit from home parenteral nutrition. These are not benefits in the sense that we would expect that the nutrition would prolong lives, but rather to prevent starvation. It is a complicated argument, but you see the point that I am making.
They did the study well, appropriately, and carefully. They put a whole range of factors into their statistical meat grinder, and what they came up with (surprise, surprise) was a performance status index and the Glasgow Prognostic Score. These were developed by friends of mine, Colin McCowan and Donald McMillan. (You can tell by my accent that I am from Glasgow). This score is a measure of systemic inflammation, looking at albumin levels and C-reactive protein.
By putting these very simple measures together, Bozzetti and colleagues could define a reasonably sizable subgroup of patients who had a prognosis of 5 or 6 months. If I had a patient in my hands who was beyond the capacity of any further chemotherapy, who had gastrointestinal blockage, and who had a sufficiently good outlook (5 or 6 months), I would be inclined to provide home parenteral nutrition, because to not do so would lead to an end of life that was, well, to say "uncomfortable" is an understatement.
This is a controversial issue, and one with no clear evidence to guide us. However, this rather thoughtful prospective study does provide us with an evidence base that allows us to make some rational decisions in this area. And it is always nice to be able to mention Glasgow and old friends in a positive way.
Have a look at the article. It recently appeared in Annals of Oncology -- a provocative piece of work, and one that could have a significant impact on clinical guidance.
Medscape Oncology © 2014 WebMD, LLC
Cite this: Help in Choosing IV Nutrition in Cachectic Cancer - Medscape - Apr 07, 2014.
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