Behind the Screen

Anyone who’s romped through to the closing pages of Betrayed by Nature will (we hope) be grateful to have come upon a succinct summary of the pros and cons of screening, particularly for breast cancer. In the UK screening (i.e. mammography: see Breast Cancer – Seeing Red, Jan 2012 for explanation) is offered to women aged 50-70 every three years – so clearly ‘we’ think it’s a Good Thing. However, the waters are less than crystal clear because several studies have concluded that as many as one in three cancers identified by mammography would not cause any symptoms during the lifetime of the patient  – and suggested that countries should spend the money on other things. The simple message you were relieved to read in BbN was that, whilst the matter is controversial, if you are offered screening, accept – whilst being aware that a ‘positive’ is not always a signal for intervention (by surgery and drugs) and that in deciding on a course of action you should be guided by the best advice your clinicians can give.

Photo: Alamy

Trying to bring resolution to this complicated and important matter, yet another ‘official review’ has just appeared in The Lancet – predictably accompanied by some absurdly inflammatory press headlines. So, ignoring them and your groans – and because it is important – can we recap the key points and reassess the clear BbN message? Of course we can – that’s what we do in “Cancer for All.”

Any type of screen for signs of cancer has two problems for those on the receiving end. First it will miss some and second it will sometimes pick up things that, although abnormal, will never become life-threatening. This latest report estimates that screening reduces the relative risk by 20%, i.e. prevents one breast cancer death for every 235 women invited for screening, equivalent to 43 preventions per 10,000 women aged 50 who are screened over the next 20 years. The downside is that about 130 women in every 10,000 are what is called ‘overdiagnosed’: they receive treatment for something that could simply be left alone. Of course that’s highly undesirable as well as stressful and unpleasant for the patient. However, it is rarely fatal – and at least carries an element of reassurance that they won’t develop breast cancer.

So, in the light of the newest info, is BbN’s take in need of modification? No, it’s just fine. What a relief!! But just bear a couple of other points in mind: the sensitivity of screening is gradually improving and dramatic improvements in analysing tumours at the molecular level mean that ‘overdiagnosing’ will decline. As we’ve pointed out, the system isn’t perfect – then neither are we or we wouldn’t get cancers – but it’s heading in the right direction.

References

Independent UK Panel on Breast Cancer Screening. The benefits and harms of breast cancer screening: an independent review. The Lancet October 2012.

http://www.telegraph.co.uk/health/healthnews/9641609/Breast-cancer-screening-harming-thousands.html

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Unkinking Kindle

In response to a wonderfully appreciative email about the book I’m posting the pictures (some in colour!!) because the reader couldn’t get Kindle to show them – although my publisher’s digital book manager cannot find any problem with the files.

Photographs (Plates 1 to 10) in Betrayed by Nature:

Plates 1 and 2

Plates 3 and 4

Plate 5

Plate 6

Plate 7

Plate 8

Plate 9

Plate 10

Review from The Biologist, Volume 59, Number 4

Betrayed by nature: the War on cancer Dr Robin Hesketh Palgrave Macmillan, £16.99

One wet afternoon in 2008, a scientist sat down to try and explain all that we know about cancer. It turned out to be a bigger task than he first thought but, four years later, we can all be glad that he stuck at it and produced a book that is both thoroughly informative and highly enjoyable to read.

The author, Dr Robin Hesketh, is a cancer biologist of some repute and has worked at the biochemistry department at Cambridge University for over 25 years. He has personally worked with many of the key players in the story of cancer treatment and relates many tales from the front line.

The book is divided into four main sections. In part one Hesketh explains the history of cancer and cancer research. Parts two and three explain the basics of how cells should normally divide and grow and then what goes wrong with various bits of molecular machinery in cancerous cells. In part four we learn about the detection and treatment of the disease and where we are going in the future.

I suspect this book is primarily intended for those who have suffered from cancer and want to understand what has happened to their bodies. But Hesketh does such a good job explaining the fundamentals of cell biology (often without the reader realising that he has done so) that anybody, from GCSE students to senior clinical biochemists, will find something of interest in this highly recommended tome.

Dr Oliver Jones CBiol MSB