Many people are confused by the medical terms used by doctors in cancer consultations, a study has shown.
Cancer terminology can be confusing
Researchers found terms commonly used by doctors in the UK such as 'progressing tumour' and 'remission', were poorly understood by the public.
They were also flummoxed by terms used to describe screening procedures for breast and bowel cancer.
Experts say the findings show there is an urgent need for doctors to change the way they communicate important information to patients.
Professor Lesley Fallowfield, from the Cancer Research UK Psychosocial Oncology Group at the University of Sussex, worked on the study.
She said: "Growing evidence suggests the majority of people with cancer want to be fully informed about their illness whether the news is good or bad.
"A clear understanding of the situation can improve a patient's treatment, recovery and quality of life.
"So it's crucial that doctors avoid ambiguous language or medical jargon in consultations."
The researchers selected potentially confusing words and phrases from 50 videotaped cancer consultations where patients had indicated they did not understand the information given or doctors used medical jargon.
They designed a detailed questionnaire with scenarios containing the terms.
Diagrams of the body, on which to locate organs that could be affected by cancer, were also included in the survey to test the participants' knowledge of basic anatomy.
Around 100 men and women, aged between 16 and 64, completed the questionnaire. Participants were also asked to rate how confident they were about their answers.
Researchers found that only six out 10 of those questioned understood that 'metastasis' meant cancer was spreading.
Only around half of the participants knew the term 'remission' meant there was no detectable sign of cancer and understood the phrase 'the tumour is progressing' was not good news.
Three out of 10 had poor understanding of the term 'seedlings' - a euphemism for the spread of cancer - and two out of 10 were confused by the phrase 'spots in the liver'.
Researchers found many of those who completed the questionnaire thought they understood terms when they were actually quite confused by them.
More than half of the study group either didn't know or showed partial understanding of breast cancer screening techniques such as mammography.
Four out of 10 had a low understanding of various methods used to detect bowel cancer.
Participants' knowledge of where organs in the body lie varied.
While nine out of 10 correctly identified the lungs only five out of 10 located the liver.
Prof Fallowfield said: "The study shows a substantial proportion of the public don't understand terms often used in cancer consultations.
"There's an urgent need for doctors to reassess the way they explain the diagnosis and treatment of cancer to patients.
"Our results would suggest using plain language, steering clear of euphemisms such as 'an abnormal growth' to describe cancer, while making sure patients know which organ is affected by the disease and where it is in the body, would help avoid confusion."
"Doctors also need to be aware that asking people if they understand what's being said is likely to overestimate comprehension and it may be better to ask what they have understood."
Dr Richard Sullivan, head of clinical programmes at Cancer Research UK, said: "Doctors have a responsibility to communicate effectively and clearly with people who have cancer to enable them to make up-to-date and informed decisions about their future."
Delyth Morgan, chief executive of Breakthrough Breast Cancer, said: "Women with breast cancer have the right to expect their diagnosis and treatment to be clearly and sensitively explained so that each woman's ability to absorb information is maximised.
"Simple steps like dispensing with medical jargon in favour of everyday language could make a big difference to all patients."
The research is published in the journal Psycho-Oncology.