5 July 2016
The SCI Scotland Group ran a PhD student competition in February 2016. Students from across Scotland (working in scientific research) competed for 12 free one-year SCI memberships. The students were asked to submit a short (~600 word) article describing their PhD research project and its relevance to the SCI strapline 'where science meets business', in a format suitable for publication in a scientific news magazine read by scientifically literate members of the general public (such as New Scientist). The 12 winners will be introduced to senior academics and industry contacts working in Scotland and will be given opportunities to build their networks and develop future skills to help with their onward careers. Katherine Ember was one of the top three entrants awarded and her award-winning article on rare cancers which will also be published in C&I magazine, can be found below.
Rare Cancers - A Tricky Business
‘Cholangiocarcinoma. You’ve probably never heard of it. And yet behind those eight syllables hides a rare, but incredibly deadly cancer. Over the past few decades, advances in diagnosis and treatment of cancer have caused mortality rates to fall dramatically and now half of people with cancer are surviving 10 years past their diagnosis, double the survival rate of the early 1970s1. But cholangiocarcinoma is different.
‘It is characterised by tumour growth in the bile duct and, if you’re diagnosed with it, your chances of still being alive five years later are about 1 in 202. The median survival post-diagnosis is less than two years3. And, unlike the statistics for most other cancers, this appalling figure has gone largely unchanged in the last three decades. So why is this? What is it about cholangiocarcinoma that means that it’s not benefitting from the same medical advances as other cancers?
‘Part of the problem is that the bile duct is not particularly accessible. It transports bile from where it’s stored in the gall bladder through the liver to the small intestine, where bile is required for fat digestion. The fact that the bile duct is quite near to the core of your body makes it challenging to image using standard techniques like MRI and CT scanning as scanning resolution decreases with depth. Due to such limitations in diagnostic technologies, cholangiocarcinoma isn’t identified early enough so tumours are often too advanced for therapy to be effective. The other part of the problem is money.
‘Cholangiocarcinoma is a rare disease, affecting 1 in every 20,000 people annually in Europe4 and rare diseases don’t draw nearly as much funding for diagnostics or therapies as those affecting a greater proportion of the population like lung, breast or skin cancers. Diagnostics companies can only thrive if their products successfully diagnose diseases, so there is an active effort to create techniques that can diagnose people early and effectively. This is a model which works well when applied to more common diseases, but it’s easy to see that rare diseases will lose out - for businesses, it doesn’t make sense economically to pour money into developing systems that will only save a few hundred lives a year. One solution is to develop diagnostic techniques that can be applied to multiple diseases, like Raman spectroscopy.
‘Raman spectroscopy is an optical technique for looking at the chemical composition of cells and tissues. When you shine light of a particular wavelength at a molecule, it can absorb the photons of light and then either emit light of the same incident wavelength or of a different wavelength. This light of a different wavelength is known as Raman scattered (or inelastically scattered) light and is dependent on bonding within the molecule. So detecting Raman scattering gives us information about what molecules a sample is made of, and we can apply this to biological tissue. Because cancerous tissue differs chemically from normal tissue, Raman spectroscopy can help doctors and surgeons work out whether someone has a tumour or not and could be combined with optical fibres for endoscopy. The aim of my PhD project is to help develop such a technique for examining the bile duct for cholangiocarcinoma. Although different disease states will give different Raman signatures, the basic principles for analysis are very similar - so diagnosing cholangiocarcinoma could assist diagnosis of other cancers and diseases that affect the bile duct. And earlier diagnosis means more effective treatment. Hundreds of millions of people worldwide suffer from rare diseases - it’s time to stop treating these diseases as rare events and time to start treating them effectively.
1. Quaresma M, et al. 40-year trends in an index of survival for all cancers combined and survival adjusted for age and sex for each cancer in England and Wales, 1971-2011: a population-based study. Lancet pii: S0140-6736(14)61396-9 (2014)
2. Boulter, L. et al. WNT signaling drives cholangiocarcinoma growth and can be pharmacologically inhibited. Journal of Clinical Investigation 125, 1269-1285, doi:10.1172/jci76452 (2015)
3. Blechacz, B. & Gores, G. J. Cholangiocarcinoma: Advances in pathogenesis, diagnosis, and treatment. Hepatology 48, 308-321, doi:10.1002/hep.22310 (2008)
4. Eckel F, et al. Biliary cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann Oncol 22 (suppl 6): vi40-vi44,doi:10.1093/annonc/mdr375(2011)
University of Edinburgh