Changing horizons in cancer treatment

Changing horizons in cancer treatment

If there’s one disease for which we still have no vaccine or cure, its cancer. Despite decades of research, new drugs and treatments, and several books on the subject – including The Emperor of All Maladies which won the Pulitzer prize five years ago – scientists are still struggling to find that miracle, life-extending cancer pill.

Though the search has been elusive, sessions at the European Society for Medical Oncology (ESMO) Asia Congress 2016, held recently in Singapore reflected the mind-boggling advances in cancer treatments.

There’s no doubt that the traditional treatment approach- surgery, radiation and chemo­therapy belongs to a bygone era. Today, two people with the same kind of cancer are likely to be on totally different prescriptions.

Oncology has moved from a one-treatment-fits-all approach to individualised treatment plans: these are tailor-made for cancer patients (in some countries), based on their genetic profiles and tumour markers.

For many women like me, Angelina Jolie was pivotal in drawing attention to genetic pre-disposition to cancer. Her decision to go public about her preventive double mastectomy (breast removal) and hysterectomy, because she tested positive tests for BRCA1 gene mutations – which increased her risk to breast and ovarian cancers – increased my awareness. Incidentally, BRCA is an abbreviation for breast cancer susceptibility gene, and two kinds of mutations- BRCA1 and 2-are commonly associated with increased risk of developing early onset breast and ovarian cancer.

Mutations or molecular abno­rmalities like these can be identified by doing DNA sequencing tests. This is scary stuff, but at least treatment breakthroughs are reassuring: trials for a new drug Olaparib – the first of its kind – have shown its effectiveness for the treatment of women with late stage ovarian cancer with BRCA1&2 mutations. 

Changes in diagnostics are also exciting. Not long ago, a tumour biopsy was essential, to confirm genetic characteristics and stage of cancer. Today, non-invasive liquid biopsy technologies have eased the situation for patients – blood is analysed to detect genetic mutations instead of tissue samples, enabling clinicians and researchers to understand the nature of individual cancers, as well as the responses to treatment. 

Indeed, “precision medicine” – which made the news when it was first pushed by the Obama administration a few years ago-has advanced dramatically. Researchers can identify what’s driving the growth of a particular tumour and develop a specific combination of therapies that target the tumour directly. New agents also boost the body’s own immune “fight” response, triggering cancer cell death.

Innovation is the hallmark of precision medicine, which pairs different approaches: immunotherapy with traditional cancer treatments – chemotherapy, targeted therapy, and radiation therapy.

Drug trials

At ESMO 2016, clinical oncologists and researchers shared the permutations and combinations that had succeeded, and failed in trials. Traditionally, drug trials were focused on cancers in specific organs but newer approaches group together patients with similar genetic mutations.

Drug trials involve smaller numbers of patients, and move faster, making it possible to bring drugs to the marker earlier than was otherwise possible. Though failures and side-effects are inevitable, when a drug does work, the response is remarkable!

No recent advance has been more transformative than immunotherapy, which unleashes the body’s own immune response to fight cancer cells. Things have moved forward since the first immunotherapeutic drug was approved by the US FDA in 2015. Now, this is used to treat advanced lung cancer- the most common and deadly cancer worldwide. New cancer drugs are more specific, and effective, offering hope to those who aren’t resp­onding to standard therapies, because they have become drug resistant or developed genetic mutations.

The prognosis for lung cancer patients has impro­ved, now that we have proof of the efficacy and potential of a drug approved by the US FDA – Osimertinib – to replace chemotherapy for the treatment of lung cancer patients with EGFR T790M mutation positive tumours.

These advances are inspiring. Let’s face it; we may not be able to avoid a confrontation with cancer. Some statistics show that one out of three people will be diagnosed with it. Even if we are lucky enough to escape, our friends and family may not. All we can hang on to is the hope that this new era of cancer therapeutics may usher in a cure.

(The author is a microbiologist who writes on health issues)