Bone tumors may present with various signs and symptoms, including pain, mass, and limb deformity. The incidence of primary malignant bone tumors is approximately 3,600 cases annually in the United States. Benign bone tumors are estimated to be 100 times more common than malignant bone tumors, although the true prevalence is unknown. The most common presenting symptom of a malignant bone tumor is pain, often associated with a mass, and occasionally pathologic fracture. Patients with benign bone tumors may present with incidental findings noted on radiographs, painful mass/lesion, or pathologic fracture.1
The patient’s age must be considered when determining the differential diagnosis. Diagnoses for pediatric patients differ significantly from those for young and older adults (Table 1
). Common bone tumors in pediatric patients include nonossifying fibromas, unicameral bone cysts, aneurysmal bone cysts, osteosarcoma, and Ewing sarcoma. By comparison, in a patient older than 40 to 50 years, bone lesions are more commonly metastatic carcinoma, multiple myeloma, lymphoma, chondrosarcoma, and secondary osteosarcomas.
It is imperative to obtain a detailed history evaluating the location of the symptom(s), onset and duration, rate of growth, alleviating or exacerbating factors, pain history, trauma history, and infection history. In general, pain related to benign entities is relatively mild, often related to activity and relieved by NSAIDs. If the bony lesion is active or aggressive, such as aneurysmal bone cyst or giant cell tumor, it may cause progressive pain or fracture. In contrast, malignant bony lesions usually cause pain that is more severe and unresponsive to anti-inflammatory treatments. Patients often characterize the pain as dull, deep, or achy that is present with activity but also at rest and at night. An associated soft-tissue mass may cause distal extremity swelling or nerve compression with neurologic symptoms.
The history should also include questions regarding constitutional symptoms, such as fever, chills, night
sweats, unintentional weight loss, fatigue, lymphadenopathy, breast or other palpable masses, and diphosphonate use. Approximately 20% to 30% of patients with Ewing sarcoma present with fever.2
In adults, metastatic disease to bone is vastly more common than primary bone malignancies, and a carcinoma or hematopoietic malignancy may present with a painful lesion or pathologic fracture. Any personal history of cancer, even diagnosed several decades prior, is a risk factor for metastatic bone disease. It is also important to identify any history of radiation, as there is a late risk of radiation-associated sarcomas. A prolonged history of diphosphonate use is a risk factor for impending or completed atypical femoral fractures, which are considered pathologic even though not neoplastic.
Table 1 Common Bone Tumor Diagnoses by Age
Patient Age (years)
ABC = aneurysmal bone cyst, FD = fibrous dysplasia, GCT = giant cell tumor, NOF = nonossifying fibroma, UBC = unicameral bone cyst
Physical examination can identify additional signs associated with the patient’s symptoms. The location, approximate size, and proximity to important structures should be noted. Palpation can reveal if the mass is soft, firm, or hard and if it is mobile or fixed. It is often possible to discern whether a soft-tissue mass is superficial or deep to the fascia by asking the patient to tense their muscles in the extremity; if the mass remains mobile, it is superficial, whereas if it becomes more immobile, it is below the fascia. A careful neurovascular assessment distal to the lesion is critical. For incidentally noted bone lesions, physical examination can diagnose the true problem that prompted medical attention. For example, if a patient presents with shoulder pain and radiographs reveal an enchondroma of the proximal humerus but the examination is consistent with subacromial impingement, the bone lesion can be designated an incidental finding, and the patient can be treated for rotator cuff pathology. The patient should also be examined for signs of systemic diseases and syndromes; for example, café-au-lait cutaneous lesions may indicate McCune-Albright syndrome, or clubbing of the fingertips may result from a pulmonary parenchymal process such as lung cancer. Other findings, such as lymphadenopathy and solid organ masses (particularly breast), may also be detected on physical examination and used to direct further diagnostics.
Similar to bone tumors, the prevalence of benign soft-tissue masses far exceeds malignant diagnoses; however, most soft-tissue sarcomas are painless, making them diagnostic challenges. Rhabdomyosarcoma is the most common malignant soft-tissue sarcoma in children, whereas undifferentiated pleomorphic sarcoma, liposarcoma, fibrosarcoma, and leiomyosarcoma are more common soft-tissue sarcoma subtypes in adults.
The history should include onset, duration, temporality, alleviating and exacerbating factors, and associated symptoms. Distal paresthesias may suggest a nerve sheath tumor or nerve compression. Masses or symptoms that fluctuate with activity may suggest a vascular or cystic component; inflammatory lymph nodes can also vary in size over time. In a patient who taking an anticoagulant medication, a growing mass might be an acute or chronic hematoma, although in these situations, malignancy must also be considered and ruled out.
The history should include inquiry into constitutional symptoms, a personal or family history of cancer, and syndromes associated with soft-tissue masses. For example, neurofibromatosis results in multiple tumors and risk of malignancy, and 5% to 10% of desmoid tumors are associated with familial adenomatous polyposis.3
A history of traumatic brain injury may lead to heterotopic ossification, and chronic renal failure can be associated with tumoral calcinosis.4
Physical examination can suggest a tumor’s size and depth to fascia. It is important to note whether the mass itself and the overlying skin are mobile. Any areas of compromised skin where the tumor is threatening to fungate may influence decisions about secondary coverage and preoperative or postoperative radiation. Peripheral nerve sheath tumors or masses compressing nerves can have a positive Tinel sign. Highly vascular lesions may
have a bruit or thrill on auscultation. Regional lymph node metastases can occur in rhabdomyosarcoma, synovial sarcoma, angiosarcoma, epithelioid sarcoma, and clear cell sarcoma; therefore, evaluation for lymphadenopathy should be performed.