Auckland District Health Board said that at the time the normal process was for fertility to be discussed with the patient by the adolescent nurse specialist.
However, on this day the nurse was on leave and there was no system in place to make sure someone else covered this in the nurse's absence.
Mr A underwent his first chemotherapy treatment as planned, and the next day a nurse mentioned fertility to Mr A and his parents.
Dr B then met Mr A and his parents on June 13 to discuss the option of storing a sperm sample, and part of this discussion took place in private without Mr A's parents present, the report said.
Mr A said he felt embarrassed to talk to a stranger about those matters and unable to fully discuss sensitive issues.
Dr B agreed that he discussed the matter separately with Mr A, but said the teen was "very clear in private conversation with him at that time that he would not have wanted to produce a sperm sample."
The DHB said it had since changed the way it managed such procedures.
Dr B said the hospital now ensured this vulnerable age group has discussions with the AYA nurse specialist in addition to the paediatric oncologist, who have now built up strong links with the Fertility Specialists.
Auckland DHB said it acknowledged the policies and processes in place at the hospital in 2008 were not adequate.
Mr Hill said Dr B failed to provide adequate information to Mr A prior to his first chemotherapy treatment, and should not have discussed giving a sperm sample without his parents' present.
The DHB was found to have breached the Code of Health and Disability Services Consumers' Rights.
Mr Hill asked the DHB to review current policies, information sheets and practice with regard to discussions of infertility with patients undergoing chemotherapy.
Both Dr B and the Auckland District Health Board have also been asked to send written apologies to Mr A.
