A new, international classification of kidney tumours will eventually result in hundreds of New Zealanders living longer and enjoying an improved quality of life, University of Otago pathologist Prof Brett Delahunt says.
''This is very big in the world of pathology,'' he added in an interview.
Prof Delahunt, of the department of pathology and nuclear medicine at Otago University's Wellington campus, has played a big role in ''more than 20 years of hard work'', also involving international and New Zealand colleagues, to produce changes in the World Health Organisation classification of kidney cancers.
He was chairman of an International Society of Urological Pathology Consensus Conference in Vancouver, Canada, last year, which developed changes, since ''implemented'', to the classification.
The new classification, and changes to what he said was a ''really unsatisfactory'' tumour ''grading'' system, had ''huge'' positive implications for patients internationally. Previous guidelines for classification and grading were ''seriously out of date''.
The work would help usher in a new era in renal tumour diagnosis and treatment, he said, with better ability to develop treatments and more accurately predict outcomes.
Renal tumours are diagnosed in about 510 New Zealanders each year, with numbers projected to rise to 630 by 2016.
It had not been until 1981 that the WHO even classified kidney cancers, and at that stage recognised only two tumour classes: ''renal cell carcinoma'' and ''other''. By 2004 there were nine different classes of tumours. That has risen to more than 20.
The latest outcome had eventually recognised that kidney cancers varied widely from each other, involving a ''completely different genetic make-up'', different behaviours, and different treatments.
The new approach would help patients in many ways, including by making clear that some slow-growing and ''very indolent'' tumours did not require so much of the kidney to be surgically removed - as had previously occurred - resulting in better long-term quality of life.
The improved classification system was also likely to encourage drug companies to develop new drugs to treat specific tumours which were now more clearly identified, he said.
