Let's Talk - Precision Medicine and ImmunotherapyOct 18, 2020
Precision medicine, genomics, immunotherapy - what do they all mean? Canopy oncologists, Dr Richard Sullivan and Dr Ben Lawrence provide their insights into what these terms mean and how they will help improve outcomes for patients.
“The future of care for people going through a cancer journey and the diagnosis of cancer is rapidly evolving. What we’re doing is trying to be smarter and understand how we can be more specific in treating a particular cancer for a particular person to achieve a better outcome with less toxicity”, explains Dr Richard Sullivan.
“We often use different words when we talk about cancer treatments – precision medicine, genomics, immunotherapy – what’s exciting is that all of our treatments are getting better and they’re now far more tolerated. We’re able to be more specific or precise about how we deliver those therapies and we’re going to get better again.
“Cancer brings with it many challenges. Firstly, there’s the diagnosis and the implication and impact it has on a patient. Then there are changes that happen to a patient’s body as a result of surgery if that’s needed. The challenge then becomes the impact of ongoing treatment, and the toxicity of that treatment. What precision medicine tries to do is reduce the toxicity and improve the outcome and quality of life for a patient.
Dr Ben Lawrence agrees “It’s an amazing time to be working in oncology and looking after people with cancer. In the time that I’ve been practicing, I’ve seen a shift from chemotherapy for everyone to, in some cancers, we don’t use chemotherapy at all.
“The big change that’s happening at the moment is our ability to understand what’s in the cancer and match that to a drug. Precision medicine has come about because we now have a much better biological understanding of what cancer is. In the past what we used to do is say ‘this cancer started in the lung or the colon or some other part’ and therefore we would use the colon cancer treatment, or the lung cancer treatment.
“What we’re now realising is there’s a lot of variation within different cancers and that variation is predominantly because of different combinations of gene mutations or gene mistakes that drive the cancer. So, rather than thinking of all lung cancers as the same or all bowel cancers are the same and using the same treatment, we recognise they’re often very diverse, so we use a different treatment for each of those cancers.
Dr Sullivan adds “There are multiple layers to cancer. At one level it’s about asking, ‘what sort of cancer does the patient have and can we be more precise and directive with the treatment?’ From there you can actually get more specific and look at whether there’s a sub-type of the cancer which means we can be even more precise again, and determine whether the patient needs what’s called, targeted therapy.
“I believe years from now, we won’t talk about cancer in the lines of breast cancer, lung cancer, bowel cancer. It’ll be around the genomic make up and it’ll be around being more precise around how you use that information to treat cancer.
“Counter to that, because there’s always a counter, is immunotherapy. This is an exciting evolution that’s occurred in the last 5 – 7 years and what it tells us, is that it’s not the cancer that’s important, it’s actually the immune system.
“Immunotherapy drugs are targeted at awakening the immune system to treat the cancer. They’re not precise at all; they are directed towards the immune system which means you can use the same drug across multiple cancers with good outcomes.”
Dr Lawrence elaborates “Immune therapies are a new kind of drug. Instead of trying to smash up the cancer cells like chemotherapy does, or switch off a gene that’s falsely activated in the cell that allows it to grow in a crazy way, immune therapies allow the body’s own immune system to attack the cancer.
“Cancer cells are clever, and they can often evade our immune system by becoming invisible to our immune system. How these drugs work is if you can imagine a cancer cell sitting in our body with a veil over the top of it, these drugs essentially pull back the veil and the immune system says ‘oh my gosh I didn’t even realise you were there’ and then it can have a go at it. The nice thing about immune therapies is for a majority of people they’re often not very toxic which means they’re better tolerated and very effective.
But he cautions, “Immune therapies are only for the right types of cancer and only for those with the right kind of gene changes or the right kind of damage to the code that’s inside the cell so they can respond to these drugs.
To watch Dr Sullivan and Dr Lawrence talk about precision medicine and immunotherapy, click here to watch Canopy TV.