Patients with lung cancer diagnosed when they go to hospital as an emergency often had difficulties in seeing their GP, a study has found.
Nearly half of patients in a study presented to the National Cancer Research Institute's conference reported something had put them off going to the doctor.
Around 40% of patients with lung cancer in England are diagnosed as an emergency case in hospital, with poor chances of survival.
Common reasons were difficulty making an appointment, not being able to see their usual doctor, not having confidence in their GP and fear of what the doctor might find.
The study was conducted by researchers from the London Cancer Alliance and King's College London, looking at 130 patients who were diagnosed after attending hospitals in South and West London.
Patients hadn't thought their symptoms were serious in 18% of those cases studied.
Delaying visiting the doctor for 12 weeks or more were reported by 20% of patients, those patients who were older, poorer and fearful of what the doctor would find were most likely to delay.
Three quarters of the patients had consulted their GP about their symptoms, and 20% had made at least three visits.
Some had already been referred for hospital visits by a GP, 23% having had referrals but then been admitted to hospital before the appointment due to the severity of their condition.
Lung Cancer is the second most commonly diagnosed cancer in the UK with around 43,500 patients diagnosed each year and around 35,400 deaths annually in the UK. Symptoms include cough, shortness of breath, chest pain and coughing up blood.
Dr Thomas Newsom-Davis, LCA Acute Oncology Services pathway chair and consultant medical oncologist at Chelsea and Westminster Hospital, said: "These findings show that we need to work together to improve patient education, ensure that those with possible lung cancer can easily make an appointment to see their GP, and that patients are quickly seen in specialist lung cancer clinics."
"It's important to pilot ways of ensuring that patients with possible symptoms of cancer can be seen in hospital before they get so ill that they are admitted as an emergency, for example, rapid-access diagnostic clinics."
