A charity is calling on GPs to ensure they do not miss cases of bone cancer after a report showed survival rates have not improved in 25 years.
The Bone Cancer Research Trust (BCRT) said symptoms include painful bones or swollen joints which GPs can easily misdiagnose as a sporting injury or "growing pains".
Bone cancer is very rare, with just 531 new cases in the UK in 2010. However, it is an aggressive form of cancer which often leaves survivors with life-changing disabilities.
Patients have around a 54% chance of surviving five years after diagnosis - a figure that has barely changed in 25 years, according to a National Cancer Intelligence Network report released in July.
The BCRT has teamed up with the Royal College of GPs to launch a specialist e-learning module to help doctors spot the symptoms and diagnose patients earlier.
Professor Andy Hall, chairman of BCRT's independent scientific advisory panel, said : "Primary bone cancer is, thankfully, very rare but it is vital that it is diagnosed early to give patients the best chance of survival.
"The Bone Cancer Research Trust is working with GPs and other health professionals to raise awareness of the disease and refer patients for further investigation whenever bone cancer is a possibility, particularly in children and young adults.
"The average length of time it takes for a primary bone cancer patient to receive a correct diagnosis is 16 weeks from the time when the patient first noticed their symptoms.
"A simple X-ray, performed early, can make all the difference."
The two most common types of primary bone cancer are osteosarcoma and Ewing's sarcoma which often affect children, teenagers and young adults.