"The potential for long-term survival, effective cure, is definitely there."
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 involving 945 patients with advanced melanoma saw them treated with two drugs - ipilimumab and nivolumab.
Researchers found the treatments stopped cancer advancing for almost a year in 58% of cases, with tumours stable or shrinking for an average of 11.5 months.
This compared to 19% of cases for just ipilimumab, with tumours stable or shrinking for an average of 2.5 months, according to the research, which was published in the New England Journal of Medicine.
Dr Alan Worsley, Cancer Research UK's senior science information officer, said the findings suggest combining immunotherapy treatments could hit advanced melanoma with a "powerful one-two punch".
He said: "Together these drugs could release the brakes on the immune system while blocking cancer's ability to hide from it."
However, Dr Worsley did sound a note of caution.
He said: "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."
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 involving 945 patients with advanced melanoma saw them treated with two drugs - ipilimumab and nivolumab.
Researchers found the treatments stopped cancer advancing for almost a year in 58% of cases, with tumours stable or shrinking for an average of 11.5 months.
This compared to 19% of cases for just ipilimumab, with tumours stable or shrinking for an average of 2.5 months, according to the research, which was published in the New England Journal of Medicine.
Dr Alan Worsley, Cancer Research UK's senior science information officer, said the findings suggest combining immunotherapy treatments could hit advanced melanoma with a "powerful one-two punch".
He said: "Together these drugs could release the brakes on the immune system while blocking cancer's ability to hide from it."
However, Dr Worsley did sound a note of caution.
He said: "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."