Health researchers are blaming institutional racism for Māori women with advanced breast cancer having less chance of surviving.
A new paper claims Māori women are half as likely as their Pakeha counterparts to reach the five-year survival mark.
"The evidence suggests these rates persist even when all factors except ethnicity are controlled for," the paper, written by researchers at Unitec and AUT and published in the New Zealand Medical Journal on Friday, says.
"Systemic ethnic inequities in cancer outcomes suggest a failure of the Ministry of Health in its role of stewardship. If, as the data suggest, all other factors are controlled for and ethnic inequities persist, we argue it is likely to be institutional racism - a pattern of behaviour that benefits one ethnic group and disadvantages another.
"Institutional racism can manifest through policy, investment decisions, mono-cultural structures and inaction. Critically, racism does not need to be intentional."
Researchers are linking it to inequity of care through inadequate screening, lack of patient support and less access to state-of-the-art treatments.
Māori are far more likely to rely on the public health system for treatment than private, the research found.
Doctors are calling on the Government to uphold Treaty obligations by working with Māori in policy making, sector design and evaluation of all aspects of the breast cancer continuum.
"Patients with metastatic breast cancer have given enough of their lives fighting the system, it's time for the system to fight for them.
"We believe that implementing the recommendations presented here will help Māori women with advanced breast cancer to live longer and healthier lives, thus improving Māori health equity and bringing the New Zealand Government closer to fulfilling its obligations under te Tiriti o Waitangi."