A top cancer specialist says Pharmac chief executive Sarah Fitt should step down over "offensive" emails, as she is "unfit to manage an organisation that has control over the lives and wellbeing of thousands of New Zealanders."

Ruth Spearing, haematologist and trustee of Chronic Lymphocytic Leukaemia Advocates, has called on Health Minister Ayesha Verrall, State Services Commissioner Peter Hughes and Pharmac chairperson Steve Maharey to demand Fitt's resignation.

Her call for Fitt's resignation comes after the release of 274 pages of Pharmac communications by Fitt and other executives under the Privacy Act to journalist and medicine advocate Rachel Smalley.

Emails revealed Pharmac's avoidance of being held to account, and a "crude, jokey clique among senior staff, swapping childish, insulting remarks", Spearing said.

"This behaviour by the leader of a government agency cannot be tolerated."

Pharmac is the government's medicine buying agency, deciding what medicines are funded for New Zealanders.

Asked by Stuff whether Fitt intended to resign, her media spokesperson said: "We are not making any comment."

Pharmac's board chairperson Steve Maharey said the emails were "unacceptable and unprofessional."

Christchurch-based Spearing​, who was made a Companion of the New Zealand Order of Merit this year, has led internationally recognised research into blood cancers for more than 30 years. Her pioneering treatments resulted in significant increases in survival rates.

Spearing said the emails about Smalley "revealed a sick, sneering culture inside Pharmac and a disgraceful attitude towards a person who has had the courage to speak out on behalf of patients who have been waiting years for Pharmac decisions on medicines".

"Sarah Fitt's comments are not just unprofessional, they are deeply offensive."

Pharmac needed reform to bring New Zealand up to the standard of similar countries, Spearing said.

"Compare ourselves with countries of a similar GDP. We are only funding 20 drugs, in comparison to 170 in similar countries. We are behind the UK, Australia, and New Zealanders are dying and suffering."

One of the emails revealed commented on Smalley crying with relief when she found out that one of the life-saving medicines she had lobbied Pharmac to fund for young children was approved.

Tauranga mother Jen Rowlands has also shed a few tears this year.

She cried at the beginning of the year when she was given a "death sentence" of two months to live after being told she had stage four melanoma, and the drugs that could save her life were not funded by Pharmac.

She cried when friends, family and complete strangers raised $100,000 for the medicine she needed.

She cried tears of joy in July when told the drugs had worked and her cancer was in remission.

Rowlands is one of many New Zealanders who face death when they fall into a funding gap, called the Medicine Gap by Smalley.

Smalley also cried when she learnt Pharmac would fund a drug that would save the lives of babies with spinal muscular atrophy.

The emails revealed a former Pharmac media advisor's response to Smalley's tears was: "I made Rachel Smalley cry, if that's not a win, I don't know what is."

Smalley told Stuff it was not her call whether Fitt should resign.

"It's important for New Zealanders to have confidence in the public service and the people who are leading some of our most powerful and important government entities.

"What I would say is that Pharmac needs a solution-focused leader who is receptive to being held to account, and can drive much-needed operational and cultural reform.

"Sarah Fitt's 'sigh..' comment in response to an editorial I wrote on cancer patients will be particularly challenging for people who have cancer, those who are self-funding medicines, or have lost loved ones to cancer. There are many cancer medicines on Pharmac's waiting list and some have been there for years. Tragically, Givealittle has become New Zealand's cancer survival platform," Smalley said.

Professor Chris Jackson, professor of oncology at Otago University, said the comments were "very poor" and reflected badly on a body that New Zealanders relied on for critical decisions.

"There certainly needs to be a look at their internal culture. They do need to have greater accountability."

The chairperson of advocacy group Patient Voice Aotearoa, Dr Malcolm Mulholland, said it was "without a doubt" that Fitt should resign.

He said the comments revealed Pharmac's culture of a "callous attitude towards patients, and an arrogance that they are untouchable".

"If the government did not call for her resignation they would have egg on their face."

He had battled for Pharmac reform for five years and said it was too slow to act on the review.