What are the presenting symptoms of bone cancer on the lower leg?

Bone Cancer Presentation in the Lower Leg

Bone cancer in the lower leg most commonly presents with persistent pain (often worse at night) followed by localized swelling, with the tibia being a frequent site for specific tumor types including osteosarcoma (around the knee), adamantinoma (tibial shaft), and Ewing sarcoma (extremity bones). 1

Primary Presenting Symptoms

Pain Characteristics

• Pain is the cardinal symptom and may vary in intensity, but night pain is a critical "red flag" requiring immediate investigation 1
• Pain often occurs at rest or during the night, distinguishing it from mechanical musculoskeletal injuries 1
• The average duration of symptoms before presentation is 3 months, though many patients present later 1
• A history of recent injury does NOT exclude bone cancer and must not prevent appropriate diagnostic workup 1

Physical Findings

• Swelling or a palpable mass develops later in the disease course, typically only when the tumor has progressed through the cortex and distended the periosteum 1
• Limitations of joint movement may be present, particularly for tumors near the knee 1
• Some patients present with pathological fracture as their initial manifestation 1

Tumor-Specific Presentations in the Lower Leg

Osteosarcoma (Most Common)

• Most frequently affects the metaphysis of long bones, particularly around the knee (distal femur and proximal tibia) 1, 2
• Peak incidence in adolescents (10-19 years), with male predominance (1.4:1) 1
• Presents with progressive pain followed by localized swelling 1

Ewing Sarcoma

• Extremity bones account for 50% of cases, with the tibia being a common site 1
• Median age at diagnosis is 15 years with male predominance (1.5:1) 1
• Similar presenting symptoms to osteosarcoma: pain and swelling 2, 3

Adamantinoma

• Highly specific for the tibial shaft (medial or distal portions) 1
• Occurs in young to middle-aged adults (20-40 years) 1
• Shows lytic and sometimes destructive areas that can lead to fracture 1

Giant Cell Tumor of Bone

• Usually occurs at the epiphyses of long bones next to joints in patients aged 20-40 years 1
• Locally aggressive and may demonstrate soft tissue mass or pathological fracture 1

Critical Clinical Assessment

History Elements to Obtain

• Duration, intensity, and diurnal variation of pain (specifically ask about night pain) 1
• Prior benign or malignant tumors 1
• Family history of cancer 1
• Previous radiotherapy exposure 1

Physical Examination Focus

• Size, consistency, and mobility of any mass 1
• Location in relation to bone 1
• Regional and local lymph node examination 1
• Adjacent joint assessment 1
• Neurovascular examination 1

Age-Based Diagnostic Considerations

The patient's age significantly influences the differential diagnosis:

• Under 5 years: Destructive bone lesions more likely represent metastatic neuroblastoma or Langerhans cell histiocytosis 1
• Ages 5-40 years: Primary bone sarcoma is more likely 1
• Over 40 years: Metastatic carcinoma or myeloma becomes the most common diagnosis and should be investigated first 1

Common Pitfalls to Avoid

• Do not dismiss persistent bone pain based on a history of recent trauma – this does not exclude malignancy 1
• Do not delay imaging for "mechanical" pain – persistent non-mechanical pain, especially at night, requires urgent radiological assessment 1
• Do not assume a normal X-ray excludes bone cancer – persistent pain or mass requires urgent MRI or referral to a bone sarcoma center 1
• Do not perform biopsy before referral to a specialist center – poorly performed biopsies can compromise treatment and limb salvage 1

Immediate Action Required

Any patient with suspected bone cancer should receive:

• Urgent X-ray of the affected site in two planes as the first investigation 1
• Urgent referral to a bone sarcoma center if X-ray shows bone destruction, new bone formation, periosteal swelling, or soft tissue swelling 1
• Patients under 40 years with suspected primary bone malignancy should be referred urgently to a bone sarcoma center 1
• Blood tests including FBC, ESR, and alkaline phosphatase before referral if possible 1