Prognosis is a very scary and powerful thing in the field of oncology. Prognostic factors often guide doctors in making treatment recommendations, and for patients and family members, it is natural to want to know what the future holds. As we learn more and more about what drives different types of cancer, we also are able to better refine a patient's prognosis. However, it is not always the case that the pace of research for treatments can keep up. This longread is an interesting example of this situation. It raises a number of ethical questions about how we understand and communicate about prognosis, and these issues are sure to grow in importance as cancer research progresses.
"A Life-Death Predictor Adds to a Cancer’s Strain" by Gina Kolata
Published in the New York Times, July 9, 2012
http://www.nytimes.com/2012/07/10/health/genetic-test-changes-game-in-cancer-prognosis.html?_r=1&pagewanted=all
Eric
This doesn't exactly relate to the message of this article, but it got me thinking about how trials are conducted in general and a comment by another blogger who couldn't get into a trial because of other, non-related medical issues:
ReplyDeleteI had already experienced, then, two trials of trials: Patients can be thrown out of trials, and patients may be placed in control groups not receiving the new drug.
There are so many different emotional angles to cancer and the emotions of realizing you are in the trial group receiving the placebo is something I'd never thought about when reading the phrase 'the trial group showed no signs of improvement in our study.'
When patients are in a trial, how do doctors break the news that they actually aren't getting the new drug? Is this a big issue among these trials and how does it affect getting people to sign up for trials?
Placebos are actually relatively uncommon in cancer clinical trials. Trials occur in phases based on where a treatment (typically a drug but it could also be a medical device or new application of a drug/device) is in the approval process. In the early phases, trials tend to be very small and are focused primarily on understanding basic questions about how the body processes a drug, what the safe tolerated dosage is, and what is the optimal means of administration. Once those are established, a trial will look at whether the treatment has an effect or activity against a type of cancer. These studies may involve a placebo but again it is relatively rare. Generally, the people being enrolled in these trials because there are no known effective treatments or the patient has already tried the known effective treatments and had the disease persist or recur.
ReplyDeleteIn later phase trials, (Phase III and IV), the goal is to define the optimal treatment (standard of care). For example, let's say Drug A is the current standard of care because it helps 70% of patients. In early phase studies, Drug B has shown it may also be helpful, possibly even better than Drug A. So a study will be designed in which the patients are randomized -- half receive Drug A (the standard -- eg, what they would receive outside the trial) and half get Drug B. Patients are followed over time to see which drug produced better outcomes.
When a placebo is used in this context, it is usually to test whether adding a drug to the standard of care is beneficial. For example, half the patients would get Drug A with Drug B and half would get Drug A with placebo (again, the equivalent to what they would get outside the trial). Placebos are not prescribed when someone has standard treatment options available because that would be unethical.
Trials can be frustrating because there is an inherent uncertainty involved. Uncertainty in terms of outcomes and in some cases in terms of what treatment is received. The way around this is twofold -- 1.) patients need to understand that trials are designed in the way that they are so that the final results will allow for meaningful scientific conclusions to be drawn. This is why trials have exclusion criteria -- it is important that if you are treating two patients with different drugs, you try to control as much as possible for any other variation besides the drugs (eg, variation among patients). 2.) Doctors need to make sure that patients understand what is involved in a trial. Informed consent is always required, but some patients may not read it carefully or the document may be written in language that is too medically technical. This also requires being up front in making sure that most patients know that trials are not going to deliver a magic bullet. While trials are where most breakthroughs occur, it is dangerous for patients to place an undue level of hope in the possible outcome, especially in early phase studies.
If doctors and patients talk frankly about their expectations, many of the emotional concerns about being part of a trial can be alleviated.
For a great overview of trials in an FAQ format, I highly recommend our Clinical Trials Fact Sheet from the NCI:
http://www.cancer.gov/cancertopics/factsheet/Information/clinical-trials
Eric