Cancer, genetics, and caring

DMacA_3 is a CMAJ Associate Editor and a professor of primary care in Northern Ireland, UK

 

Could cancer simply be due to bad luck rather than environmental factors, risky behaviour or bad habits? In recent weeks, media attention focused on a scientific discussion on the risk of cancer based on papers published in Science and Nature. While the discussion itself is fascinating, isn’t it interesting that this debate took place across mainstream scientific publications rather than in established medical journals. Perhaps medicine is already convinced by the epidemiology or, maybe medical journals are less open to such debate. This is the story:

Early in 2015, argued that in the course of normal stem-cell divisions there is always a risk of random mutations during DNA replication and, based on this mathematical risk, developing cancer may simply be bad luck. Tomasetti and Vogelstein had shown a strong correlation (0.81) with the total number of divisions of the normal self-renewing cells with some cancers and suggested that only a third of the variation in cancer risk was attributable to environmental factors or inherited predispositions.

Just a few weeks ago, directly countered this proposal arguing that correlation wasn’t sufficient to explain risk and based their argument on modelling, epidemiology and mutational fingerprints. While we know a lot about cancer risk, we still don’t know exactly what causes it. I enjoyed this debate. We still have a lot to learn.

Could genome-editing technology offer health benefits and what are the ethical issues? The widespread optimism that gene mapping would offer great insight into disease risk was premature and we still struggle with the balance between genotype and phenotype. Genetic research has, however, continued to explore a number of diagnostic and therapeutic areas, and my attention was drawn towards recently towards gene editing, its potential and ethical concerns, in a flurry of articles in the media relating to Crispr - including , , and and in Nature with Jennifer Doudna, one of the key researchers.

In contrast to the excitement of scientific debate, discovery and controversy, my 2015 ended with two family funerals in the week before Christmas. The Irish funeral is a wonderful event where religion and tradition overlap, giving family and friends an opportunity to share memories, swap stories and remember loved ones in a curious blend of prayer, celebration and sadness. It’s always lovely to catch up with our wider family although it’s a pity that it takes a death to bring everyone together. The two deaths, of an older aunt and uncle were very different. One had been ill for many years with multiple hospital admissions and ongoing continuous care from her general practitioner and extended primary care team. The other was an emergency admission followed by a short period of time in intensive care on a ventilator. I listened carefully to relatives describe their experiences of medical care in different parts of the country and despite the very different clinical scenarios there was, happily, a common theme- the care, kindness, and respect offered by our medical colleagues to both families on each occasion. While clinical scientists, researchers and, indeed, medical journals focus on the forefront of medicine, trying to publish the very latest scientific advance, it is the kindness and sensitivity within medicine that stills makes the greatest difference to patients and their families at the end of life. Let’s look forward to a New Year of exciting scientific discovery while still remembering what really matters. *Cum Scientia Caritas. Compassion with knowledge.

*Cum Scientia Caritas is the motto of , London, UK