Bone cancer is a malignant tumor that destroys healthy bone tissue. In contrast to metastatic cancer that starts in another part of the body and only later spreads to the bone, the term bone cancer or primary bone cancer refers to cancer that originates in the bone itself. Bone cancer is rare -- in 2015, it will account for about 0.2 percent of all newly diagnosed cancers, according to estimates from the National Cancer Institute. Pain and swelling are typical early symptoms in all 3 of the most common bone cancers -- osteosarcoma, chondrosarcoma and Ewing sarcoma.

Pain

At first, the pain of bone cancer may come and go. It may get worse at night, or with movement. For example, a person may feel leg pain while walking, which may result in limping. As the tumor grows and presses on healthy tissue, the pain becomes stronger and more constant. Although pain is the most common symptom of bone cancer, not all people with bone cancer experience pain. Symptoms vary depending on the size and location of the tumor, as well. Tumors in the head, spine or pelvic bones may not become particularly painful until later in the course of the disease.

Swelling

A bone tumor growing in or near a joint may cause the affected joint to swell and become tender or stiff. Such symptoms can limit a person's ability to move his limb. It may even be possible to feel a lump in the area, which can be painful when touched. If a tumor forms in the bones of the neck, it can cause difficulty with swallowing and breathing. Pain and swelling do not always emerge together. Swelling may sometimes appear weeks after the onset of pain.

Fractures and Other Uncommon Early Symptoms

Bone tumors weaken the bones in which they are growing and may eventually cause the bones to break. Sudden, severe pain in a limb that had been sore for a while may indicate a bone fracture. However, bone fractures are uncommon until later stages of bone cancer. Other relatively late symptoms of bone cancer may include fever, weight loss, anemia -- a low number of red blood cells -- and tiredness.

When to Seek Medical Attention

Seek immediate medical care if you think you have suffered a broken bone. Also seek emergency care for any problems with swallowing or breathing. You should seek prompt medical attention if you have bone pain or swelling that doesn't go away or worsens over time, if your joints feel stiff or if you find a bump on your bones. Such symptoms are not necessarily a sign of bone cancer -- bone pain and swelling is much more often due to arthritis than cancer -- but a doctor can evaluate you further if necessary.