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Two cases of post-radiation osteosarcoma of the sacrum after pelvic irradiation for uterine cervical cancer.

BACKGROUND
Post-radiation pelvic bone sarcoma can result as a long-term sequela of pelvic irradiation for uterine cervical cancer.


CASE
A 59-year-old woman who had received pelvic irradiation for Stage IIB uterine cervical cancer 16 years before was diagnosed as having post-radiation osteosarcoma of the sacrum. Another 66-year-old woman who had received pelvic irradiation for Stage IIIB uterine cervical cancer seven years previously was also diagnosed as having pleomorphic sarcoma of the sacrum.


CONCLUSION
When a bone lesion is observed at a previously irradiated field, post-radiation sarcoma should be considered and differentiated from bone metastases.