Early detection of lung cancer

Sam Janes, Clinical Advisor for LungHealth UK and Check4Cancer, talks about shockingly high mortality rates for lung cancer, the importance of screening, and how new test methods can save more lives.

 

Most people are aware that smoking causes cancer, but may now believe that with reductions in smoking this issue is solved. What is the scale of problem?

There are 35,000 lung cancer deaths in the UK each year, and it’s the biggest cancer killer of men and women. So, even though smoking may be less widespread now, we are dealing with a 20-30 year legacy. It is now starting to fall among men, but it’s been rising in women, and is probably just coming to a peak.

How do survival rates compare with other cancers?

Five year survival rate for lung cancer is around 8-9% in the UK, which is very poor, and that’s largely because most patients present when the disease has already spread, and at that stage becomes incurable. Symptoms of lung cancer can be fairly non-specific, so tend to be the same as those people with chest problems experience – a cough, or shortness of breath. It is also similar to a range of far less serious complaints. It may be like a smoker’s cough, or if you have a flu-like virus you can be left with a cough for some time, which might be the same kind of cough that you might get in a lung cancer. Other symptoms, such as coughing up blood, can be relatively rare. There’s no lump to feel with lung cancer – it’s all very much on the inside. And because lung cancers can often be out on the periphery of the lung, it doesn’t necessarily block air coming in or going out, so it’s not like a bowel cancer where you might get constipation, or like a mouth cancer or skin cancer where you’re going to notice a lump at a very early stage. It’s a hidden cancer.

It has been said that if detection rates for lung cancer were able to match those for breast cancer, we would see a transformation in the survival rate...

A key issue is that there is no national screening programme for lung cancer, as there is for breast cancer. Lung cancer is not like breast cancer or bowel cancer, where screening is population-based. Those screenings happen with age, but lung cancer has clearly identifiable risk factors – so you are at higher risk of lung cancer the more you smoke, the older you are and, to some extent, the more lung disease that you have had. There are also not the same kinds of genetic predispositions that you have with BRCA1 for breast cancer, for example. If you can detect lung cancer at the earliest stage among the at-risk population, then obviously that’s good – and that’s what many methods aim to do. CT screening, for example, aims to pick up the lung cancer at the earliest stages so you can then have surgery or some other curative therapy. And that’s where we need to get to – we need to have some sort of radiological screen or blood test that detects these cancers as early as possible.

The most eagerly anticipated test is Early Lung CDT, undergoing trials in Scotland. What can you tell us about that?

The trial is ongoing, and we don’t know the result yet, but the hope is that through the blood test we will be able to detect lung cancer at a stage when it’s operable. The issues with blood tests is that they have to be sensitive enough to pick up the cancer – but they also have to be specific, because if we all test positive then, yes, it would catch all the cancers but we’d really be no further forward.

How does the test work?

It’s detecting antibodies that we make in response to foreign substances. What cancer often does is cause changes in proteins, and those are detected by the body, which creates antibodies to those changes. And that’s what we’re looking for in the blood test. But also, when cancer cells die they can release DNA which floats around in your blood, and many laboratories are now trying to investigate this to see if they can detect changes that potentially mean cancer is present.

What methods does LungCheck use to pick up cancer early?

LungCheck will let patients know about any new test that could potentially inform someone they have lung cancer at the earliest positive time. Currently we use the EarlyLung CDT test, and if that’s positive we decide whether you should proceed to checks via a CT scan. The ease, low cost and portability of the test make it a very useful tool – you just have a blood test, which can be administered by a nurse, and it gets sent off for examination. But while we’re using the EarlyLung CDT test now, the idea is that if another test came along that potentially looked more useful, then that’s the one that would be recommended.

What are the LungHealth UK OneStop Clinics?

The LungCheck service does occasionally lead to the need for further tests, should your results indicate a high risk. If this is necessary, LungHealth UK has a growing national network of LungHealth UK OneStop clinics throughout the UK with local leading thoracic and oncology consultants. OneStop Lung clinics are generally for symptomatic men and women, and aim to make the process of diagnosis through to treatment as fast as possible. Once you’ve been established as having a higher risk of getting lung cancer the consultant you’re referred to can advise you on the action that needs to be taken.

Why are these kinds of screening important?

It just comes back to the fact that at the moment, doctors generally don’t see lung cancer patients until it’s too late. Currently, there isn’t national CT screening – and in fact, in the UK there is not any kind of national lung cancer screening at all. So, what Check4Cancer are trying to offer is a blood test that can fill that gap – and from the earliest data this test is looking promising.

Sam JanesProf Sam Janes

Professor Janes is a Consultant in Respiratory Medicine at University College London Hospitals NHS Foundation Trust, where he also offers acute care and treats patients with lung cancer. He is the lead clinician for lung cancer across North Central and North East London and is an expert bronchoscopist. He also heads a research group, running laboratory and clinical trials with the aim of understanding how lung cancer develops, and to try and diagnose and treat it at the earliest possible point. Professor Janes has published the majority of the work performed in the UK on Endobronchial Ultrasound (EBUS). He is also building the European Respiratory Society Education work plan and chairs the British Thoracic Society Meeting Committee. He was appointed Professor of Respiratory Medicine at UCL in August 2013.