The Cancer Society says waiting times for treament are increasing patients' anxiety and adding to their stress.
It says most cancer treatment centres around the country have fewer specialists than is needed to treat patients.
In the Wellington region, Capital and Coast District Health Board says it has received a complaint about the waiting time to see a medical oncologist - a specialist in chemotherapy.
It says while no patients who require a specialist appointment immediately or urgently are waiting for one, 43 people considered semi-urgent are on the waiting list, and five are overdue for an appointment.
The Cancer Society's Wellington manager of support and information, Fiona Pearson, says patients are already under stress and the waiting time adds to it.
Ms Pearson says she understands a number of specialists have retired or moved into the private sector in the past few years, which has left a gap in public health.
