Sarcoma Symptoms
The cardinal symptom of bone sarcoma is persistent, progressive bone pain that occurs predominantly at night and at rest, which distinguishes it from mechanical musculoskeletal injuries and represents a critical "red flag" requiring immediate radiological investigation. 1, 2
Primary Presenting Symptoms
Pain Characteristics
- Night pain is the most specific and concerning feature that should prompt urgent evaluation, as it is non-mechanical in nature and persists even during rest 1, 2
- Pain intensity varies but is often progressive over time, with an average symptom duration of 3 months before patients seek medical attention 2
- The pain pattern differs fundamentally from traumatic or mechanical injuries—it does not improve with rest and may worsen at night 1, 2
Later-Stage Symptoms
- Swelling becomes apparent when the tumor has progressed through the bone cortex and distended the periosteum, representing a more advanced presentation 1
- Functional impairment of the affected limb occurs as the tumor enlarges and involves surrounding structures 1
- A palpable mass may be present, particularly in soft tissue sarcomas, though soft tissue sarcomas are typically painless unlike bone sarcomas 3, 4
Critical Clinical Context for the Thigh Lesion
Important Diagnostic Pitfall
A history of recent trauma does NOT exclude sarcoma and must never prevent appropriate diagnostic workup, as sarcomas can present after injury or be mistaken for traumatic hematomas 2, 5
- The case of a 16-year-old with extraskeletal Ewing's sarcoma initially misdiagnosed as traumatic hematoma, who died of metastases, illustrates this critical error 5
Specific Considerations for Thigh Location
- Osteosarcoma most commonly affects the metaphysis of long bones around the knee (distal femur and proximal tibia) 2
- Ewing sarcoma accounts for 50% of cases in extremity bones, with soft tissue origin possible in 30% of adult cases 1
- Soft tissue sarcomas of the thigh typically present as an enlarging mass, and the presence of pain does not reliably distinguish benign from malignant lesions 4
Constitutional Symptoms
- Constitutional symptoms are rare in sarcomas, so their absence should not provide false reassurance 3
Age-Specific Symptom Interpretation
- In patients under 40 years, persistent bone pain with the characteristics described above should raise strong suspicion for primary bone sarcoma 2
- In patients over 40 years, bone metastases and myeloma become more common than primary sarcomas, though both remain in the differential 1, 2
Immediate Action Required
Any patient presenting with persistent non-mechanical bone pain, especially with night pain, requires:
- Urgent conventional radiograph in two planes as the first investigation 1, 2
- If radiographs show bone destruction, new bone formation, periosteal swelling, or soft tissue swelling, immediate referral to a bone sarcoma center is mandatory 2
- MRI of the whole compartment with adjacent joints for definitive local assessment 1
Key Differential Diagnosis
The differential diagnosis includes osteomyelitis, benign tumors, and bone metastases—all of which are more common than primary bone sarcomas—but the symptom pattern of progressive night pain strongly favors malignancy 1