A study(1) released earlier this month has been making its rounds on the internet, and has quickly become a hot topic on social media. I have seen some sensational headlines stating that this study “proves that chemotherapy spreads cancer” and “is the death blow to chemotherapy.” Statements such as these are typically the hallmark of an agenda-driven view, a poor understanding of science, or a combination of both.
This study in question was performed on cells in the laboratory, and examined what we call neoadjuvant chemotherapy. Neoadjuvant chemotherapy is given before surgery, typically in an attempt to shrink a tumor and make it more amenable to surgery. This can be distinguished from other forms of chemotherapy, such as adjuvant chemotherapy (given after surgery) and palliative chemotherapy (to address symptoms of advanced cancer). All chemotherapy cannot and should not be lumped into one large category, but should instead be thought of in terms of the context in which it is being used.
Regarding neoadjuvant chemotherapy, we have good evidence that this approach not only improves surgical outcomes, but overall treatment outcomes as well. For example, this study(2) reviewed all of the existing literature regarding neoadjuvant chemotherapy and breast cancer. It is a good summary of the situations in which neoadjuvant chemotherapy is effective against breast cancer. There are similar reviews of many other cancer types as well.
MD Anderson even has a calculator(3) you can use to show, based on studies, what kind of anticipated effect neoadjuvant chemotherapy has for a given type and stage of cancer.
Neoadjuvant chemotherapy is appropriate in certain situations, and improves outcomes, and this has been established over many years and in multiple studies. So how do we reconcile that knowledge with the study in question? First, we must look at the type of study performed.
Studies performed on isolated cells in the lab are considered quite preliminary in the scientific world. They represent the first inquiry into a possible treatment or therapy. The first question in a game of 20 questions, if you will. In other words, with cell line studies, we are obtaining some preliminary data to see if we want to continue our investigation. We are not drawing conclusions at that point.
If results from isolated cell studies seem promising, we progress to animal studies. If these studies show success, we move to human studies. Just because something has an effect on cells in a petri dish does not mean that it has the same effect in the body. The petri dish is a nice, controlled, straightforward environment. Contrast that to the very complex, and at times, chaotic environment inside the body! In many cases, we are dealing with apples and oranges.
With that said, these study results are potentially important. In fact, they should encourage us to perform additional studies to see if we continue to see the same results in animals and humans. If neoadjuvant chemotherapy is shown in certain settings to cause more harm than good, we will adapt our practices. That is the basis of the science-based practice of medicine.
Chemotherapy works, and this study does nothing to invalidate its effectiveness. However, in my experience, it should be used in an intelligent manner, as safely as possible, and in conjunction with other therapies including both conventional and natural treatments. That is what we do in integrative oncology.
References:
1. http://stm.sciencemag.org/content/9/397/eaan0026
2. https://www.ncbi.nlm.nih.gov/pubmed/20187061
3. http://www3.mdanderson.org/app/medcalc/index.cfm?pagename=bcnt
