December 2007 podcast transcript

00:00

Kat: Welcome to the December Cancer Research UK podcast, with me, Dr Kat Arney. This month we hear how our scientists are doing to improve the outlook for children with cancer, as well as finding out if bacon really does give you cancer.

Coming up later, actor Richard E Grant reveals his first impressions of our research labs. But first here's the news with Josephine Querido.

00:52

Josephine: It's been known for some time that women who take the combined oral contraceptive pill are at an increased risk of cervical cancer.

The good news is that Cancer Research UK researchers have now shown that the risk starts falling soon after the pill is stopped.

Women currently using the pill and who have been using it for at least five years are at nearly twice the risk of cervical cancer compared with women who have never used the pill.

According to the study, published in the medical journal the Lancet, the extra cervical cancer risk disappears ten years after someone stops taking the pill.

Led by Dr Jane Green at the University of Oxford, the researchers looked at 24 separate studies of more than 52,000 women from 26 countries worldwide. Previous research has also shown that taking the pill increases breast cancer risk but decreases the risk of ovarian and womb cancer.

The study was jointly funded by the World Health Organisation, the International Agency for Research on Cancer, and Cancer Research UK.

Here’s Dr Lesley Walker, Director of Cancer Information at Cancer Research UK, to explain more.

"The important thing is to weigh up the risks and benefits of being on the pill - many women find that the benefits outweigh the risks. Also the risk drops when you stop taking the pill, and will get back to normal after a period of time.

And the most important thing is to keep going for screening - i'’s one of the most successful measures we have for preventing cancer, it's there already, so take advantage of it."

02:14

Josephine:The largest ever study of cancer risk in women - Cancer Research UK's Million Women Study - has concluded that half of all cases of womb cancer and a type of oesophageal cancer are caused by women being overweight or obese.

Published in the British Medical Journal, this study provides the first reliable evidence on the relevance of being overweight or obese for a wide range of cancers in women in the UK today.

Its findings suggest that among middle aged and older women in the UK, around 6,000 cancers each year are caused by being overweight or obese.

The researchers also found that excess weight increases the risk of kidney cancer, leukaemia, multiple myeloma, pancreatic cancer, non-Hodgkin's lymphoma, ovarian cancer and, in some age-groups, breast and bowel cancer.

As well as increasing cancer risk, being overweight or obese is linked to other common illnesses such as diabetes and heart problems.

In association with the charity Weight Concern, Cancer Research UK has produced Ten Top Tips for healthy weight loss, based on scientific evidence. Find out more from the Healthy Living section of our News & Resources website.

Kat: And if you want find out more about these stories, or get the latest from the charity's scientists, and researchers around the world, then have a look at our News & Resources website.

03:38

Last month saw the publication of the World Cancer Research Fund's Expert report on Food, Nutrition, Physical Activity and the Prevention of Cancer. It caused headlines like "Row over bacon scare", and "Is anything safe to eat?"

I asked Ed Yong, Senior Health Information Officer here at Cancer Research UK to explain the truth behind the report. I started off by asking him how the WCRF had come to their conclusions.

"People complain all the time that scientists disagree over the latest evidence about what causes cancer. So the WCRF got some of the world's top experts together in a room and got them to look at what we actually know about the causes of cancer and what you can do to prevent the disease.

They looked at lots of different topics, to do with diet, obesity, meat, fibre etc, looked at all the studies that are available and worked out what the current consensus is.

We're talking about thousands of studies - this is very reliable stuff. These people have the expertise to look at all the studies and work out which ones are reliable and which are not.

The WCRF have ten key recommendations, but to summarise, keeping a healthy bodyweight and getting lots of physical activity will reduce your risk of cancer, likewise cutting down on foods that promote weight gain will stave off cancer.

In terms of your diet, it's the same messages that we've been saying for a while - you need a healthy balanced diet, high in plant foods like fibre and fruit and vegetables, and low in animal foods such as red and processed meat.

These are very strong recommendations from some of the top scientists in this field, so I think we should be taking them very seriously.

With regard to bacon, the point is that none of these recommendations are asking people to avoid anything completely - these are recommendations, not commandments.

But I think it would be very irresponsible for the WCRF, Cancer Research UK or any other organisation to know about things that increase the risk of cancer but not tell the public about them."

06:42

Kat: It's not every day that an A-list celebrity pops into Cancer Research UK's London Research Institute, so we were pleased to welcome actor Richard E Grant for a recent visit. His latest film "Cuckoo" sees Grant playing a research professor trying to keep his staff working in his laboratory, so he was keen to soak up the atmosphere of a few of the charity's real life labs.

I asked him for his first impressions of the world of cancer research.

Richard explains that he found the labs very informal. People are very intense and obsessive about the things that they’re involved with, and have to have an immense patience.

You could spend five years on something and not have the result you’re hoping for, which takes a certain kind of personality. It was very useful to see people like that. But then in the canteen everybody is talking like everywhere else. The scientists are just people who are very, very good at what they do.

He was surprised by how young everybody was - he expected to see more beardy, crusty professor-types! He was impressed by the way Cancer Research UK’s scientists are driven by curiosity to understand how the world works. But it's very complicated and the techno-speak is overwhelming.

He was also surprised to know that the charity's research is not government funded, and hope that in the future if he ever needs it, he will be able to get help as a result of the work done here.

09:09

Kat: December is traditionally childhood cancer month and although the disease is still thankfully rare, over the years the outlook for children with cancer has changed dramatically.

Back in the 1960s only a quarter of children would survive the disease, but now this is more than three quarters. But we still need to do more to understand the causes of childhood cancer and work towards more effective treatments with fewer long-term side effects.

Cancer Research UK helps to fund a wide range of research into childhood cancer - so we sent our reporter Anna Lacey to visit some of the scientists involved. She started at The Institute of Cancer Research in Sutton, South London, where she asked Professor Nazneen Rahman about what we mean by "childhood cancer".

"Generally childhood cancer is any cancer that occurs in individuals below the age of 18, but that covers different types of cancer, including leukamias and solid tumours - tumours affecting the organs such as the kidney or the liver.

There is some difference between the cancers that affect children compare with those that affect adults. The cancers that are most common in adults are often linked to ageing or exposure. For example, lung cancer is usually related to smoking, and is extremely rare in children.

For childhood cancers on of the areas that is different compared with adult cancers is that some of them are related to disrgeulated development of particular organs. This has either occurred during embryonal development (in the womb) or in early childhood.

You go from one cell at conception to millions of cells when a baby is born. At that stage the organs are under intensive growth, but once a baby is born the factors that are promoting growth have to be tailed down and switched off. But if that doesn't happen, and the cells are being told to grow very fast, then you can end up with a tumour.”

Anna: That was Nazneen Rahman from the Institute of Cancer Research. So what can we do if the cells won't stop growing? Well fortunately, there are a number of options, as Great Ormond Street Hospital's Penelope Brock explains.

"Most children with cancer need multiple treatments - they need chemotherapy, surgery if they have a solid tumour, and some children go on to have radiotherapy."

Anna: The problem with some of these treatments is that they can be very aggressive - after all they have to kill the cancer cells. But in the process, healthy cells can be damaged too, and this can lead to lasting side effects.

Surprisingly, no-one knew about the long-term impacts of being treated for childhood cancer - that is, until the British Childhood Cancer Survivors Study came along. They sent out questionnaires to 16000 people who were treated for childhood cancer between 1940 and 1991 with the aim of finding out how they might have been affected physically, mentally and socially. Mike Hawkins is leading the study.

"On the health side we're looking at problem with the digestive system, thyroid, the heart and so on. And particularly for women, these treatments can have an effect on their ovaries.

We also ask about kids that they've had. When we set the study up, we were concerned that the effects of the treatments might be passed onto the next generation and cause birth defects. But I'm pleased to say that based on many thousands of kids born to the survivors, there's no evidence of that.

With regard to physical health - are you able to dress yourself on a daily basis, are you able to climb the stairs, can you walk a mile - it turned out that particularly survivors of bone or brain cancers didn't fare as well as the general population. But the good news is that a lot of the other groups weren't far off the general population."

Anna: That was Dr Mike Hawkins from Birmingham University. In order to find out which treatments give the best results without side effects, scientists carry out clinical trials. Penelope Brock is running a study called SIOPEL 6, which is trying to develop a new way of treating children with hepatoblastoma - a rare type of liver cancer.

"Hepatoblastoma is treated with one or two chemotherapy drugs, the most important drug is cisplatin. Cisplatin is toxic to the kidneys and to the ears. It causes what we call high frequency deafness, which are essential for speech - loss of the consonant sounds.

Because hepatoblastoma affects children at an average age of 18 months, they haven't yet learnt how to speak. And if you lose the sound of the consonants when you're very young, and it is a permanent hearing loss, they have difficulties with speech and language development.

We are going to use a chemoprotectant agent called sodium thiosulphate. We hope it will reduce the hearing loss caused by the cisplatin, by blocking to activity of the drug in the ear.

I think it's the way we're going for children who have curable diseases, and one way is to minimise the amount of toxic therapy that is given. The other way is to try and add in medication or other methods that will reduce the toxicity."

16:16

We've reached the end once more so we hope youve enjoyed the podcast. Don't forget that your feedback is vital in helping us improve the show, so please send us your comments and suggestions by email to podcast@cancer.org.uk. And you can sign up to our RSS feed to get the latest Cancer Research UK podcast delivered straight to your computer every month.

We'll be back next month with all the latest news from Cancer Research UK. Until then, good bye.

• Credits:
• Presented and produced by Kat Arney
• News by Josephine Querido and Kat Arney
• Childhood cancer package by Anna Lacey
• Post-production by Henry Sowcroft
• Original music written and performed by Kat Arney and Henry Scowcroft
• With special thanks to all the participants