A plastic surgeon and clinic have been faulted for failing to tell a man he needed to be treated for suspected skin cancer.
The patient only found out by chance when he went back to his family doctor more than a year later.
An investigation by the Health and Disability Commissioner shows the clinic's patient record system was largely to blame.
The man first went to his GP in 2012, complaining about a bleeding patch on his scalp.
He was referred to a plastic and reconstructive surgeon, who took samples of skin tissue.
Results showed it was skin cancer, which was affecting the patient's nose and scalp.
But the specialist and the clinic failed to tell the man, despite being assured he would be notified.
It was only revealed he had skin cancer when the patient went back to his GP for vaccinations for overseas travel, and the doctor looked up the plastic surgeon's report showing there was cancer.
The man said the breach of care meant he had to undergo far more invasive, painful and time-consuming surgery.
The specialist told the Commissioner he did not remember how the mistake happened, but said it was likely he signed off the test result when he was away on a conference.
The clinic has since made changes to its systems for handling patient test results.
The Commissioner also suggested the clinic should carry out an audit of its records since August 2012 to ensure all patients have been given their results and any necessary follow-ups.
The Health and Disability Commissioner is urging patients to step up and question clinics about their treatment.
Anthony Hill told Checkpoint patients need to be partners in their own care.
"My instincts would say, in a biopsy situation, always call back.
"Always have the conversation with your provider, should I call back on these results, that's the general conversation for all test results, and I guess if in doubt, call back," he said.