29 year old adult with pain in his leg. case submitted by Dr MGK Murthy, Mr Hari Om and Mr Sahadev.
Plain Film: There is large ill defined , diffuse , grossly destructive , predominantly bone forming lesion seen involving the metadiaphyseal regions of fibula with wide zone of transition, large soft tissue swelling. Possibility of primary bone tumor of malignant etiology at this stage.
Next most cost effective investigation: Today MRI (preferably with contrast) combined with Fluorine (F18) bone scan is considered as the Platinum standard in Clinical Practice , as it would give us bone(CT in it), Chest (F18bone scan being whole body)(for excluding secondaries/infective focus), MR for Soft tissue evaluation, contrast for showing soft tissue invasion of the tumor tissue
MRI findings: It shows large, ill defined, mildly expansile and grossly destructive metadiaphyseal lesion of fibula upperend with complete loss of Soft tissue differentiation(suggesting involvement), with areas of new bone formation , and loss of periosteal definition.
MR is supposed to show non-mineralized tissue as intermediate on T1 and bright on T2, new bone formation as persistently low on all sequences, loss of tissue interfaces including intermuscular fat planes and presence of blood as varying heterogenous signals , along with sunburst appearance/codman’s triangle for periosteal contact etc. Other relevant features expected to helpfor surgery are vessel encasement and extension across the knee joint surface, and tibiofibular syndesmosis
Follow up: Chest X ray in this case was negative and bone Biopsy revealed Primary-bone forming malignant neoplasm – osteosarcoma of possibly intramedullary variety .
Fibular osteosarcoma-Imaging Reviewed by Sumer Sethi on Thursday, August 18, 2011 Rating: