Services for blood cancer patients are inadequate nationally and in crisis in the Auckland District Health Board's area, a support group says.
Demand for stem cell transplants has grown because of population growth and ageing, the rising incidence of some blood cancers, and technical improvements enabling more patients to receive the treatment.
The Leukaemia and Blood Foundation says this has strained the health system's capacity, leaving some patients waiting longer than is acceptable and risking life-threatening progression of their disease.
"Existing services are severely under-resourced and have reached a crisis point in at least one centre, Auckland."
It cites shortages of haematology medical specialists, trainee specialists and nurses.
"Across the country there are shortages of haematologists," foundation medical director Professor Peter Browett - a haematologist - said on Friday.
"Dunedin has a shortage of two, in Auckland we are advertising for one, Whangarei is advertising for one."
Stem cell transplants, including bone marrow transplants, are done at Auckland City, Wellington, Christchurch, Waikato and Palmerston North hospitals.
The Auckland District Health Board said the need for transplants had increased by half in three years, and since last year it had sent 12 patients to other regions for transplants when its own unit was full.
Clinical services general manager Fionnagh Dougan said the transplant unit had been increased to seven beds, from five, and officials were investigating further expansion.
But any decisions on that had to await the outcome of a Health Ministry national review.
Ms Dougan said she knew of only one Auckland patient who had been kept waiting for more than the "target" of six weeks for a bone marrow transplant. The person had to wait an extra three days.
Blood cancers - mainly leukaemia, lymphoma and myeloma - are New Zealand's fifth most common form of cancer. They are the third most common cause of cancer death, at more than 900 deaths a year.
Aucklander Suzanne Wein, 31, is in remission from lymphoma, after chemotherapy, radiation and two bone marrow transplants.
A doctoral student in neuroscience and part-time physiotherapist, Mrs Wein said she was not aware of treatment delays after her diagnosis in 2006, but she was sent to Australia twice, at the health board's expense, for specialised scans to help decide the best course of treatment.
This was because at that time there was no suitable positron emission tomography scanning machine in the North Island.
The cancer diagnosis came out of the blue, when Mrs Wein was in the peak of fitness, participating in running events. She had gone to the doctor about a lump in her neck.
Cancer treatment took over her life, and she must still take a variety of medicines but now, she said, "I'm doing good".
Her main health worry was that when she wanted to have a family, she would have to use IVF because cancer treatment had harmed her fertility.
Professor Browett said blood cancers suffered from poor public awareness.
"Everybody knows about breast cancer, melanoma or prostate cancer. Blood cancers like leukaemia and myeloma ... the terms are not well understood."
He said the number of lymphoma cases in Western countries was increasing by about 10 per cent a year.
Apart from population growth and ageing, no one knew why.