Symptoms & Diagnosis
Soft tissue sarcoma usually present as a soft tissue mass without any pain. Symptoms may occur in and around the joints, causing swelling and tenderness. Bone tumors can weaken the bones, causing bone pain and fractures. Symptoms usually do not show up until the disease is advanced, but a doctor should be contacted regarding the following symptoms: a new or growing lump appears, increasing abdominal pain, and/or blood in stools or in vomit.
Tumors that recur after excision are very suggestive of a malignant or aggressive benign tumor.
Soft-tissue sarcomas are diagnosed through a surgical biopsy and appropriate imaging (MRI, CT, and/or PET). The grade of the tumor is determined by how abnormal the cancer cells appear when examined under a microscope and by evaluation of the growth rate by PET imaging.
Low-grade sarcomas, although cancerous, are unlikely to metastasize but may recur locally at the site of origin. High-grade sarcomas are more likely to spread to other parts of the body.
For bone cancers, the doctor may suggest a blood test to determine the level of an enzyme called alkaline phosphatase; a high level can be found when there is a disease or tumor. High levels of this enzyme can also be found in children and adolescents with growing bones, so the test is not a reliable determination of bone cancer. Bone cancers are also diagnosed by X-rays and imaging tests, such as a bone scan, an MRI, or PET imaging. Regardless of how bone cancer is initially diagnosed, a biopsy is needed to confirm whether or not cancer is present.
Adult patients over the age of 40 years who present with a bony abnormality or bone tumor should be evaluated carefully for an unknown primary tumor of lungs, kidneys, breast, or prostate that has possibly spread to the skeleton (metastasis). That evaluation requires CT of the lung and abdomen and a total body bone scan or the skeleton.