ASCO 2015 round-up: immunotherapy continues to come of age

As you’ll have probably spotted by the array of cancer stories in the media over the last week, the world’s biggest annual cancer conference has just taken place.

The annual American Society of Clinical Oncology (ASCO) meeting brings together over 30,000 oncology professionals from around the world to discuss research into new treatments, practices and scientific insights.

A number of studies picked up global media attention, so let’s have a look at what some of the more exciting stories were.

Exciting immunotherapy drugs

Much of the excitement at the conference – amplified by the resulting headlines – focused on two immunotherapy treatments showing great promise in treating a range of cancers.

So what are these new treatments? And how significant were these results?

Rather than targeting a tumour directly, immunotherapy works by recruiting immune cells to target the disease instead.

Watch an animation about how these drugs work

One type of drug that received particular attention at the conference binds to a molecule on our immune cells called PD-1. This effectively stops one of the ways cancer cells avoid being destroyed by our immune cells. These drugs have been generating interest for some time – we took a detailed look at the science behind them last year.

One study presented at this year’s conference compared one of these ‘anti-PD-1’ drugs – nivolumab – to chemotherapy for patients with advanced lung cancer. Those receiving the immunotherapy treatment survived for several months longer than those on chemotherapy, and with fewer side effects. These are really promising results for lung cancer patients, offering real progress for a cancer that currently has very few treatment options.

Another study, which received worldwide media attention, used a combination of different immunotherapy drugs to treat patients with advanced melanoma. In this case, nivolumab was combined with another drug known as ipilimumab , that works in a slightly different way: it releases the brakes on the immune system.

“This could be the beginning of a whole new era in cancer treatment” – Professor Peter Johnson, Cancer Research UK

This ‘one-two punch’ meant that well over half (57 per cent) of patients in the study responded to the treatment, as opposed to only a fifth (19 per cent) who were given ipilimumab alone.

But on the downside, there were also far more severe side effects as a result of the combination of treatments.

Many more studies looked into various combinations of immunotherapy treatments in several cancer types – for example head and neck cancers, liver cancer, and certain types of bowel cancer.

It’s been clear for some time that immunotherapy treatments are slowly coming of age, but this news is a big step forward. There are now clear signs that, in some cases, they can extend survival, and even shrink tumours entirely.

Next we need to work out which patients will get the most benefit from these treatments, figure out how we can manage the side effects, and determine what combination will have the most impact. This is especially true given that these drugs are not going to be cheap.

But it’s clear that immunotherapy will be playing a key role in the future of cancer treatment.

Obesity – a growing concern

More than four in 10 cancers are preventable in the UK through healthy lifestyle changes. So despite the excitement about new drugs, it’s incredibly important to remember that prevention can be just as important as finding new treatments.

One of the other high-profile stories coming out of ASCO that hit the headlines was a statement from the conference on obesity, suggesting that it is “poised to overtake smoking” as the key lifestyle-linked cause of cancer.

In the UK, almost two-thirds of people are overweight or obese – and carrying excess weight increases the risk of up to 10 different types of cancer – including breast and bowel cancer.

Obesity is linked to around 18,000 cases of cancer a year in the UK, so the statement is a call–to-action to make sure people have the information and support they need to make healthier choices.

Statins – jury still out

Statins – drugs regularly prescribed to help people lower their cholesterol levels – also made an appearance at the conference – with headlines suggesting that “taking them could halve the risk of cancer” after two large studies reported a link.

But there are some drawbacks to the way the studies were carried out. They were ‘observational’: only involving people who had already been diagnosed with cancer and then looking back to record how long they had been taking statins, if at all.

At the moment this is only showing a statistical link, and there isn’t enough evidence to prove that anyone should take statins to lower their risk of dying from cancer.

We need proper, forward-looking randomised controlled trials – such as the Cancer Research UK-funded LungStar trial – to show whether statins can help people with cancer.

Other cancer treatments

As you might expect from a conference with more than 30,000 attendees, this was just the tip of the iceberg. For example, two other notable studies looked at new breast cancer drugs which – while certainly not cures – could offer patients with advanced cancer an extra option.

And it’s not just about drug treatment – this interesting bowel cancer trial looked at using tiny radioactive spheres, injected into the liver, to try to halt the growth of tumours that had spread there.

The results were encouraging, but more data are needed to show whether the treatment had long-term benefits.

Kids and Teens

And lastly with some other good news – a look back at data on childhood cancer survivors has found the work going into finding kinder treatments is really paying off. While treatments for childhood cancer have dramatically improved survival rates over the last four decades, treatments can be harsh, and things do – very occasionally – go wrong.

But this is changing. The study showed that, as treatments improve, the likelihood of a childhood or teenage cancer survivor dying from the long term side effects of cancer treatment has consistently declined between the early 1970s and early 1990s, according to data presented at the conference.

This is a great example of the progress being made in finding more effective and kinder treatments for children, teenagers and young adults with cancer.

But more work needs to be done to ensure that every young person diagnosed with cancer is able to live the longest, fullest life possible. To see why this is a priority for us at Cancer Research UK – you can read more at Cancer Research UK Kids & Teens.

– Alan