Media playback is unsupported on your device Media caption Father 'completely floored' by diagnosis of 11-year-old's cancer

Some 42% of parents of children diagnosed with cancer felt their concerns about their child's health were ignored by GPs, research suggests.

A third (34%) felt their child's diagnosis was delayed and half of those felt this had an impact on prognosis.

Cancer charity CLIC Sargent is calling for the government to ensure better training and guidance for professionals who care for children before diagnosis.

NHS England said new guidance had lowered the referral threshold for GPS.

The research by CLIC Sargent, released to the BBC's Victoria Derbyshire programme, is based on a survey of 333 people - 147 young people aged 16-24 and 186 parents.

Emotional impact

The charity says each year about 3,800 children and young people are diagnosed with cancer in the UK.

About 44% of the young people surveyed said they felt they were not taken seriously enough, making multiple trips to the GP or hospital before they were eventually diagnosed.

Over half - 53% - of the young people felt they had received a delayed diagnosis. Of these, 93% believed the perceived delay added to their emotional stress.

Case study - Gemma Hakner, now 22, was 17 when she was diagnosed with cancer.

In 2010, I felt some lymph node lumps in my neck and became obsessive about it, I knew something was wrong.

I kept going back to the same doctor for six or seven months and he kept telling me that I was fine and there was nothing wrong, I didn't have cancer.

My family and friends kept teasing me, they thought I was being a hypochondriac.

In January 2011 I saw another GP, who told me to come back in two weeks if things hadn't changed. When they didn't, I was referred to hospital.

My diagnosis was sort of a relief more than anything - obviously I knew something was wrong and now it was getting dealt with.

Looking back at it now, doctors can't be expected to know everything. Maybe this doctor had not dealt with any young people with cancer, so maybe he just thought it was something innocent.

CLIC Sargent wants the NHS to conduct more research into the impact a delayed diagnosis has on a child or young person's health outcome, treatment and survival rate.

63% of parents said the delay had a negative effect on the emotional wellbeing of their child.

CLIC Sargent chief executive Kate Lee said: "It is simply not acceptable that so many of the parents and young people we spoke to felt their GP didn't take their concerns seriously or that their knowledge of their child's health wasn't recognised.

"It is absolutely vital that medical professionals including GPs are confident and skilled in listening and talking to children, young people and parents - and responding to their concerns. That's why we're calling for health education bodies to make this a core element of professional training."

As part of its research, the charity also commissioned a survey of 1,000 GPs. It found 46% felt more training was needed to help them identify cancer in children and young people, while 50% said more consultation time would be beneficial.

Ms Lee added: "It is striking that so many GPs feel more can be done to help them identify suspected cancer. Cancer in children and young people is thankfully rare so a GP may only have one or two cases in their whole career."

Sean Duffy, national clinical director for cancer at NHS England, said: "Early diagnosis must be of the highest priority for cancer patients of all ages. This report highlights the challenges of identifying cancer in children, and shows the vital need for everyone, including GPs, to be more aware of the early signs.

"NICE guidance has been recently updated to lower the referral threshold for GPs, and we have begun a major programme of work to test innovative ways to diagnose cancer more quickly in all patients."

The Victoria Derbyshire programme is broadcast on weekdays between 09:15 and 11:00 on BBC Two and the BBC News channel.