Osteosarcoma in a teenager

Osteosarcoma often develops in growing bones near the knee, shoulder, or another large joint. A teenager may first notice pain after sport, a change in running, or swelling that does not settle as an expected strain would. The pain can become present at rest or during sleep. These symptoms are not specific to cancer: sports injuries, inflammation, and other bone conditions can look similar. A careful assessment is needed rather than assuming the explanation.

Book an appointment when pain, swelling, or a limp continues or interferes with school, sport, sleep, or daily activities. Write down when symptoms began, what makes them worse, and whether there has been a fall or impact. A clinician may examine strength, movement, and the painful area before arranging an X-ray or other imaging. If a tumour is suspected, referral to a specialist team helps coordinate biopsy and treatment. Care may include [Chemotherapy](/treatments/systemic-therapy/chemotherapy/) and [Tumour Removal Surgery](/treatments/surgical-oncology/tumour-removal-surgery/).

Contact a clinician promptly for a persistent lump, unexplained night pain, or a limp that is getting worse. Go to urgent care for sudden intense pain, a suspected broken bone, inability to use the limb, or new numbness or weakness. A trusted adult can help the teenager describe symptoms and attend appointments.

Could this be an injury or another bone condition? What imaging is needed? When would a biopsy be considered? How can treatment affect school, sport, fertility, or body image? What emotional and practical support is available?