Post Pelvic Radiotherapy Bony Changes

There has been recent interest in radiation-induced bone injury in clinical conditions, especially for pelvic insufficiency fracture (PIF). A PIF is caused by the effect of normal or physiological stress on bone with demineralization and decreased elastic resistance. Pelvic radiotherapy (RT) can also contribute to the development of a PIF. A PIF has been regarded as a rare complication with the use of megavoltage equipment. However, recent studies have reported the incidence of PIFs as $8.2{\sim}20%$ after pelvic RT in gynecological patients, an incidence that was higher than previously believed. The importance of understanding a PIF lies in the potential for misdiagnosis as a bony metastasis. If patients complain of pelvic pain after whole-pelvis radiation therapy, the presence of a PIF must be considered in the differential diagnosis. The use of multibeam arrangements and conformal RT to reduce the volume and dose of irradiated pelvic bone can be helpful to minimize the risk of fracture. In addition to a PIF, osteonecrosis and avascular necrosis of the femoral head can develop after radiation therapy. Osteoradionecrosis of the pelvic bone is a clinical diagnostic challenge that must be differentiated from an osseous metastasis. A post-radiation bone sarcoma can result as a long-term sequela of pelvic irradiation for uterine cervical cancer.

골반 방사선 치료후의 골 변화와 손상

방사선치료후 발생할 수 있는 골 손상은 골반 부전골절, 방사선 골 괴사, 무혈성 괴사, 골 육종 등이다, 특히 최근 방사선치료후의 골탄성도의 변화로 발생하는 골반 부전골절에 관하여 많은 보고가 있었다. 과거 방사선치료 후의 골 손상 특히 골절의 빈도는 선형가속기를 이용한 메가볼트 방사선치료 바뀌면서 현저히 줄어 들어서 매우 낮은 것으로 보고 되었으나 최근에는 $8{\sim}20%$로 보고가 되고 있다. 따라서 골반 부전골절의 임상적 의미와 중요성과 예방 및 치료에 대하여 관심이 증가되고 있다. 저자는 자궁경부암 치료 후 관찰한 골반 부전골절, 골 괴사, 무혈성 괴사, 및 2차성 골육종등 골반골 변화와 손상에 관하여 저자의 경험과 문헌고찰을 통하여 보고 하고자 한다.