Subsequent cancer in patients with Ewing's sarcoma

Area of Science:

• Oncology
• Radiation Oncology
• Cancer Survivorship

Background:

• Ewing's sarcoma is a rare bone and soft tissue cancer primarily affecting children and young adults.
• Long-term survival rates for Ewing's sarcoma have improved, leading to increased focus on late effects of treatment.
• Understanding the risk of secondary malignancies in survivors is critical for comprehensive long-term care.

Observation:

• A study of 31 long-term Ewing's sarcoma survivors identified two cases of second primary cancers.
• One survivor developed renal medullary neuroblastoma, unrelated to Ewing's sarcoma or its treatment.
• Another survivor developed a radiation-induced bone fibrosarcoma at the original tumor site.

Findings:

• The observed rate of second cancers was significantly higher than expected (relative risk = 72).
• A potential increased risk of radiation-induced bone sarcomas was noted following megavoltage radiation therapy.
• While not statistically significant in this small cohort, the trend suggests a link between radiation dose and secondary bone sarcomas.

Implications:

• Ewing's sarcoma survivors may have a heightened susceptibility to developing radiogenic sarcomas.
• Optimizing radiation therapy techniques to use the lowest effective dose is paramount.
• This underscores the importance of long-term surveillance for secondary cancers in Ewing's sarcoma survivors.