Cancer breakthrough after ‘spectacular’ melanoma results

Immunotherapy is proving so effective that in one British-led trial, more than half of patients with advanced melanoma saw tumours shrink or brought under control, researchers said.

A number of trials of the drugs have been presented at the American Society of Clinical Oncology’s annual conference in Chicago.

Professor Roy Herbst, of the Yale Cancer Centre in the US, called some of the findings “spectacular”.

“I think we are seeing a paradigm shift in the way oncology is being treated,” he said. “The potential for long-term survival, effective cure, is definitely there.”

Patient, heal thyself. But it's not a miracle yet

There are two reasons why today's findings on skin cancer are so exciting, writes Channel 4 News Science Editor Tom Clarke. First, and most obviously, people with untreatable melanoma who would otherwise have had months to live, now might now live a lot longer. But second, and most importantly, we now know that an entire field of scientific endeavour looks like it will pay off - and change the way we treat cancer for good.

For decades scientists have known the immune system can slow the spread of cancer. But they have had to spend years tinkering with ways to make the immune system specifically target cancer, without turning it against every cell in our bodies. The potential benefits are huge. Conventional cancer treatments like radiotherapy and chemotherapy kill rapidly dividing cells - that includes health ones. Using them to fight cancer is usually a balance between giving enough to kill the cancer, but not so much that you kill the patient.

Because the immune system is so very targeted, and it can "remember" what it is supposed to be attacking, tricking it into attacking cancer has the potential to eliminate tumours anywhere in the body with far less damaging side-effects. "Immunotherapy" is the next big thing in cancer care - and today's findings show it's starting to deliver.

But we're not quite there yet. In trials of immunotherapy drugs (there are currently three licensed for use in the US, including both the ones in today's trial and one in the UK, with several more on the way), many of the patients don't respond to them at all. Scientists still have a lot to learn about why some patients respond well to immunotherapy and others don't. But the field of cancer therpay is taking major steps forward.

‘New era’

Professor Peter Johnson, director of medical oncology at Cancer Research UK, said: “The evidence suggests we are at the beginning of a whole new era for cancer treatments.”

An international trial on 945 patients with advanced melanoma, led by the Royal Marsden Hospital in London, saw them treated with the drugs ipilimumab and nivolumab.

I think we are seeing a paradigm shift in the way oncology is being treated. Prof Roy Herbst, Yale Cancer Center

The treatments stopped cancer advancing for nearly a year in 58 per cent of cases, with tumours stable or shrinking for an average of 11.5 months, researchers found.

This was compared to 19 per cent of cases for ipilimumab alone, with tumours stable or shrinking for an average of 2.5 months, according to the research published in the New England Journal of Medicine.

Severe side-effects?

Dr Alan Worsley, Cancer Research UK’s senior science information officer, said: “This research suggests that we could give a powerful one-two punch against advanced melanoma by combining immunotherapy treatments.

“Together these drugs could release the brakes on the immune system while blocking cancer’s ability to hide from it.

“But combining these treatments also increases the likelihood of potentially quite severe side effects. Identifying which patients are most likely to benefit will be key to bringing our best weapons to bear against the disease.”

Below: left CT scan shows melanoma pre-treatment, in red circle; right image shows melanoma post-treatment