Osteosarcoma: Characteristics, Diagnosis, Treatment, and the Role of Radiology

Osteosarcoma is a malignant and aggressive form of bone cancer characterized by the abnormal production of immature bone tissue by cancerous cells. This cancer primarily affects long bones, such as those in the arms and legs, and is most common among adolescents and young adults. Early diagnosis followed by proper treatment can significantly increase remission rates, although recurrence is still high. Studies indicate a complete remission rate in about 60% of cases, with recurrence rates reaching up to 40% after initial treatment.

Characteristics and Key Symptoms of Osteosarcoma Osteosarcoma most often arises in bones around the knees (distal femur and proximal tibia) and, less frequently, in the bones of the arms (proximal humerus). The disease is more common in males, who represent approximately 60% of cases, and predominantly affects young people aged 10-25, a period of accelerated bone growth.

Warning signs for osteosarcoma include:

• Persistent, progressive bone pain, especially at night: The most common symptom, which does not ease with rest and tends to worsen.
• Swelling at the affected site: Mainly around the knees and elbows.
• Bone fragility and spontaneous fractures: The affected bone becomes more prone to fractures.
• Unexplained fever and fatigue: These may appear in advanced cases.

Distribution and Occurrence of Osteosarcoma Osteosarcoma is most frequent among adolescents and young adults. In Brazil, the highest incidence is in the South and Southeast regions, where there is better infrastructure for diagnosis and treatment. The disease affects people of various social backgrounds and significantly impacts young individuals, who may experience physical and psychological limitations due to treatment. Loss of functionality and potential amputations are complications that affect these patients’ social and professional lives.

The Importance of Radiology in Diagnosis and Monitoring Radiology is essential for the early detection and monitoring of osteosarcoma, offering detailed information about tumor extension and behavior. Initial X-rays are critical for identifying bone changes and are complemented by more advanced imaging.

Key radiological exams include:

• X-rays: Detect affected areas and provide an initial assessment of the tumor’s extent.
• Computed Tomography (CT): Evaluates surrounding tissue invasion.
• Magnetic Resonance Imaging (MRI): Provides a precise view for surgical planning and soft tissue assessment.
• Bone Scintigraphy and PET Scan: Track possible metastasis and evaluate treatment response.

Treatment Approaches Osteosarcoma treatment is complex and typically includes surgery, chemotherapy, and occasionally radiation therapy. Chemotherapy is a crucial component, used both pre- and post-surgery to shrink the tumor and eliminate remaining cancerous cells.

Treatment options include:

• Limb-sparing Surgery: When feasible, preserves the affected limb by removing only the tumor.
• Amputation: Necessary in cases where the tumor is too advanced, or limb preservation is not possible.
• Neoadjuvant and Adjuvant Chemotherapy: Used before and after surgery to reduce the tumor and minimize recurrence risks.
• Radiation Therapy: Primarily for recurrence cases or when surgery is not viable, as osteosarcoma is generally resistant to radiation.

Physical and Psychological Sequelae Osteosarcoma can leave both physical and psychological sequelae. Physical effects include movement difficulties, the need for prostheses, and functional limitations after surgery or amputation. Intensive treatment may also cause cardiovascular and renal complications, especially due to chemotherapy. Psychologically, the disease can affect self-esteem and mental well-being, particularly for young patients undergoing long and, at times, painful treatment.

Origin and Historical Background of Osteosarcoma Osteosarcoma was first described in the 19th century and initially had high mortality rates. However, since the late 20th century, advances in limb-preserving surgery and chemotherapy have increased remission rates. The tumor’s origin is often linked to rapid bone growth, explaining its prevalence among adolescents.

Precautions and Prevention There are no specific prevention methods for osteosarcoma, given its association with genetic factors and bone growth. However, paying attention to symptoms such as persistent bone pain, especially in young people, can help detect the disease early and improve remission prospects.

Metastasis and Complications Osteosarcoma frequently metastasizes, particularly to the lungs, followed by other bones. The risk of metastasis complicates treatment and often worsens the prognosis. Lung metastases can appear early, even before the primary tumor is detected. Advanced imaging techniques are essential for tracking and monitoring metastatic spread, which directly influences the treatment plan and patient outlook.

Conclusion Osteosarcoma is a challenging disease, but early diagnosis and appropriate treatment significantly improve the chances of a favorable outcome. Radiology plays a crucial role in early detection and monitoring, enabling precise tracking of treatment response. Awareness of warning signs and access to medical care are essential for improving the prognosis and quality of life for patients.