Senedd members debated a damning review that found cancer services have consistently failed to hit a 75% target for patients to start treatment within 62 days.
James Evans, the Conservatives' shadow health secretary, said the Welsh Government has failed to deliver timely, life-saving cancer care that people expect and deserve.
He welcomed a statement on improving cancer care, which was published on January 22, the day of the debate, but warned the pace of change in Wales has been far too slow.
He told the Senedd: "The Audit Wales report laid bare the truth: the 62-day target for treatment has not been met, not once. Despite a 54% increase in spending on cancer services since 2009, failures remain."
"Workforce shortages, outdated diagnostic equipment and chaotic leadership have created a postcode lottery of care – this is simply not good enough."
'Worst survival rates'
Mabon ap Gwynfor, whose father lives with cancer, said: "The findings are things that I can relate to and have often experienced. And the sad truth is that the findings were not surprising at all, as they reflect the experiences of far too many people and their families."
Plaid Cymru's shadow health secretary said almost half of cancer patients are not receiving the treatment they need within 62 days, with no sign of hitting the goal of 80% by 2026.
Raising concerns about serious shortcomings in the workforce, he pointed to a 12% shortage of clinical oncologists in Wales which is expected to rise to 28% by 2028.
Data from the less survivable cancers taskforce showed 61% of people in Wales diagnosed with cancer of the lung, liver, brain, oesophagus, pancreas or stomach will die within a year.
Mr ap Gwynfor warned Wales has some of the worst survival rates. He said: "Out of 33 comparative countries, Wales is 21st for liver and oesophageal cancer, 31st for pancreatic and lung cancer, and 32nd for stomach cancer."
'Bureaucratic hurdle'
Samuel Kurtz was similarly concerned by survival rates for some of the deadliest cancers. He said: "These are not just statistics, these represent lives lost and families grieving. Worse still, the gap in outcomes between the most and least deprived continues to widen."
The Tory warned barriers extend beyond delays with certain cancer drugs approved by NICE for some conditions but not for others where they could save lives.
"Life should not hang in the balance because of this bureaucratic hurdle," he said.
Labour's Julie Morgan focused on the new Velindre Cancer Centre in her Cardiff North constituency which presents a "huge opportunity to create a new centre of excellence".
But Tory Sam Rowlands warned of a disparity across Wales, with about three oncologists for every 100,000 older people in the north, "so it's no wonder they're at breaking point".
'Alarming'
Plaid Cymru's Sioned Williams warned of worsening inequalities in cancer care.
She said someone from one of Wales' poorest areas will be almost 20% more likely to develop cancer on average and 17% less likely to survive five years.
Ms Williams told the Senedd: "More damning still is the fact that mortality rates from cancer are 55% higher in our most deprived areas."
"The clear message that emerges from these alarming statistics is that poverty literally kills you – it puts its thumb on the scale that decides the length of your life in this world."
Conservative Gareth Davies said: "One of my family members...had early stages of liver cancer last year, and do you know what she said to me? She said, 'I'm glad my treatment was not in Wales.' She has not got a political bone in her body."
'Stabilised'
Responding to the debate, Jeremy Miles pointed to the Welsh Government's quality statement on cancer which sets expectations and standards for services.
He said performance on the 62-day target has stabilised, with some signs of progress, but he accepted "far too much" variation remains between health boards and cancer types.
The health secretary said the Welsh Government will establish a national leadership group to co-ordinate improvement of cancer services.
Mr Miles welcomed the Audit Wales report recommendations, saying: "It's unequivocal in its conclusion that we are committed to improving cancer services but that there is more to do."
Senedd members voted 34-12 against the Tory motion, with Plaid Cymru amendments also falling before the Welsh Government's amended version was agreed 33-13.

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