Lung cancer is the biggest cancer killer in Scotland and long term survival rates are poor as only one in 10 patients are still alive five years after diagnosis.
A poll by the UK Lung Cancer Coalition (UKLCC) found that two thirds of lung specialists believed that early diagnosis was the most important factor for improving five-year survival rates.
But a separate survey of 100 lung cancer patients or their carers found that 36 per cent waited more than a month for a definitive diagnosis - and 17 per cent waited over two months.
Meanwhile, 43 per cent of patients said they waited for more than a month for the initiation of treatment after a diagnosis was confirmed.
Dr Marianne Nicolson, consultant medical oncologist at Aberdeen Royal Infirmary, said: “Currently only one in ten people with lung cancer are still alive five years after diagnosis in Scotland.
“Despite concerted efforts to tackle inequalities and improve prevention and outcomes, five-year survival rates in Scotland still lag severely behind our European counterparts and compare poorly with other major common cancer types.
“Steps to improve early diagnosis, along with better treatments, will work together to improve survival.”
Improvements need to be made around regional variations of care as mortality rates can differ by up to 20 per cent between different parts of the country, the report said.
The coalition challenged the Scottish Government to drive up survival rates to 25 per cent by 2025, which could save around 1,300 Scots if achieved.
UKLCC chair Richard Steyn said: “This report breathes new energy and enthusiasm into a lung cancer community which recognises that there is much more work to do.
“A lung cancer diagnosis should not be a death sentence.”
The Scottish Government launched a £100 million cancer strategy earlier this year which aims to improve survival by boosting early detection rates.
Health Secretary Shona Robison said: “Lung cancer death rates have dropped by 13 per cent over the past decade and early detection is vitally important to continuing this trend.
“Our £100 million Cancer Strategy is aimed at improving prevention, detection, diagnosis, treatment and after care.
“Since the launch of our Detect Cancer Early Programme lung cancer diagnoses at stage one has increased by almost 36 per cent, increasing to 44 per cent in the most deprived areas.
“Smoking continues to be the biggest cause of preventable death in Scotland. Quitting tobacco is the best thing a smoker can do to improve their health.
“NHS Scotland offers a range options through its smoking cessation services to help people quit, and we will continue to use resources effectively to achieve a smoke-free generation by 2034.”
Joanna Marshall was diagnosed with late stage lung cancer in March 2015, despite never having smoked a cigarette.
The 39-year-old thought she simply had a cold, compounded her busy lifestyle raising her two young children and working as a regulatory affairs manager for Diageo.
A stubborn cough forced her to return to her doctor, who referred her to a specialist when she coughed up a small amount of blood.
Tests confirmed that she had a tumour in her right lung and the cancer had spread to her lymph nodes.
Despite the poor prognosis, Ms Marshall, of Bridge of Allan, has continued to work full time.
She said: “I just couldn’t believe it. Part of me has never believed it because I am doing so well.
“People with stage four lung cancer don’t look like me. But anyone with lungs can get cancer.”
Bouts of radiotherapy and chemotherapy followed, but she found out earlier this year that the cancer had spread to her brain.
Ms Marshall is now managing the cancer with a drug therapy.
She said: “There are challenges to my quality of life but I am still a working mum, which is what I want.”