First off, sorry for the lack of writing in the last few weeks; I’ve been in the middle of a job hunt, so my time has been limited by that. In the time I have taken off however, there have been some major news stories about cancer.
The week of the 15th February brought some pretty sensational headlines. These were about a trial of a new immunotherapy, which both The Times and the Independent proclaimed “a cure”, and The Guardian labelled as “unprecedented”.
Immunotherapy is an extremely promising branch of cancer therapy that has recently been getting a lot of attention. I have previously written about it here, so I won’t go into detail about how exactly it works. Simply put, it involves taking some of a cancer patient’s immune cells, teaching them to recognise the tumour, and then putting them back into the patient. These immune cells can now identify the cancer, attack it, and hopefully clear it from the system.
These results have not been published yet (they were presented at a conference), so we can’t say for sure how reliable they are. We do know however, that the trial had just 36 patients on it, and that it was looking at a cancer we can already treat with a high degree of success (acute lymphoblastic leukaemia (ALL)), so the headlines were far more sensational than the work deserves. That being said, it does appear to be a very encouraging study. However, as I have previously written, claiming something is a “cure” for cancer is likely to be wrong.
This treatment appears to be very effective for ALL, and it may eventually become part of the standard therapy for this disease. However, ALL is just one of a large number of different types of cancer. Couple this with the ability of the disease to develop resistance to therapy and it becomes unlikely that this (or any other therapy) will ever be a “cure” for cancer. So while this is certainly an exciting advance, claiming it is a cure is unfortunately incorrect. It may have the potential to cure some patients, but without long term testing, we just don’t know if this is the case.
This problem of resistance brings me to the second big cancer story that’s been in the news recently. Coincidentally, it is also to do with immunotherapy. In this study, scientists found that a patient’s cancer carry markers that the immune system could be primed to attack, as I described above.
However, it has always been assumed that as a tumour develops, it would change and evolve, resulting in some cells that no longer have these markers, and would therefore be resistant to the immune cells taught to target those markers. What is interesting about this study is that the scientists showed that this may not always be the case, and that all of a patient’s tumour cells may still carry the markers, meaning they would all be attacked by the immune system. The video below (from CRUK) describes this very nicely.
The potential that a patient won’t develop resistance to a therapy is one that scientists and doctors can only hope for. If this study holds, and is extended to other cancers, this dream may become a reality for some people. Again, this is a study on very few patients, but it gives us a tantalising glance at a potential weakness in cancer that could be exploited.
It is an exciting time to be a cancer researcher!