What’s the Diagnosis – Case 141
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What’s the Diagnosis – Case 141
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What’s the Diagnosis – Case 141
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What’s the Diagnosis – Case 141
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Findings Again, not focusing on the hip arthoplasties, there is little change in the architecture of the bones of the pelvis. There are multiples areas of dense sclerosis and slight thickening of the bone involving both sides of the pelvis. A chronic fracturing is present about the pubis. As a pertinent negative, no destructive mass is present of the bones of the pelvis.
What’s the Diagnosis – Case 141
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What’s the Diagnosis – Case 141
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What’s the Diagnosis – Case 141
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What’s the Diagnosis – Case 141
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What’s the Diagnosis – Case 141
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Diagnosis: Radiation Changes of the Bone The important portion of the history not given is that this patient underwent prior radiation therapy for ovarian cancer slightly greater than 10 years before the original set of images shown. Radiation is known to alter the bone in many ways by altering the microvascular environment, collagen synthesis, alkaline phosphatase activity, and number of osteoblasts to name some. This sets up a situation where bone is predisposed to fracture as seen in this case and frequently with a poor healing response. Depending on the dose of radiation imparted the bone may suffer damage and become ischemic leading to radiation osteitis or become frankly necrotic. Discerning between these two processes can be very difficult radiographically as both produce irregular, markedly sclerotic bone with areas of demineralization/radiolucency. Both of these processes also predispose to fracture. Not germane to this case but radiation can also induce growth disturbances in the skeletally immature patient. The last set of processes induced by radiation are neoplasms. The most common neoplasm is an osteochondroma. Radiation sarcoma (most commonly osteosarcoma or fibrosarcoma) is precipitated many years following radiation treatment. The marrow after radiation treatment can be very heterogeneous on MRI or CT. The key to the diagnosis of sarcoma is a destructive mass and particularly if this represents a change from prior imaging. As a differential diagnosis, particularly Paget disease of bone can mimic radiation changes. However, as in this case notice there is just sclerotic bone and not really coarse trabeculae. There is also not the marked thickening/enlargement of the bone as seen in Paget and it would be uncommon for Paget to involve both sides of the pelvis. That being said, at times discerning these two entities can be difficult. What’s the Diagnosis – Case 141
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References From radiation osteitis to osteoradionecrosis: incidence and MR morphology of radiation-induced sacral pathologies following pelvic radiotherapy. Meixel AJ, Hauswald H, Delorme S, Jobke B. Eur Radiol. 2018 Aug;28(8):3550-3559. doi: 10.1007/s00330-018-5325-2. Epub 2018 Feb 23. Pelvic bone complications after radiation therapy of uterine cervical cancer: evaluation with MRI. Kwon JW, Huh SJ, Yoon YC, Choi SH, Jung JY, Oh D, Choe BK. AJR Am J Roentgenol. 2008 Oct;191(4):987-94. doi: 10.2214/AJR.07.3634.
What’s the Diagnosis – Case 141
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