Role of MRI in osteosarcoma for evaluation and prediction of chemotherapy response: correlation with histological necrosis
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Jyoti Bajpai & Shivanand Gamnagatti & Rakesh Kumar & Vishnubhatla Sreenivas & Mehar Chand Sharma & Shah Alam Khan & Shishir Rastogi & Arun Malhotra &
- چاپ و سال / کشور: 2010
Description
Background Histological necrosis, the current standard for response evaluation in osteosarcoma, is attainable after neoadjuvant chemotherapy. Objective To establish the role of surrogate markers of response prediction and evaluation using MRI in the early phases of the disease. Materials and methods Thirty-one treatment-naive osteosarcoma patients received three cycles of neoadjuvant chemotherapy followed by surgery during 2006.2008. All patients underwent baseline and post-chemotherapy conventional, diffusion-weighted and dynamic contrast-enhanced MRI. Taking histological response (good response .90% necrosis) as the reference standard, various parameters ofMRI were compared to it. A tumor was considered ellipsoidal; volume, average tumor plane and its relative value (average tumor plane relative/body surface area) was calculated using the standard formula for ellipse. Receiver operating characteristic curves were generated to assess best threshold and predictability. After deriving thresholds for each parameter in univariable analysis, multivariable analysis was carried out. Results Both pre-and post-chemotherapy absolute and relative-size parameters correlated well with necrosis. Apparent diffusion coefficient did not correlate with necrosis; however, on adjusting for volume, significant correlation was found. Thus, we could derive a new parameter: diffusion per unit volume. Conclusion In osteosarcoma, chemotherapy response can be predicted and evaluated by conventional and diffusionweighted MRI early in the disease course and it correlates well with necrosis. Further, newly derived parameter diffusion per unit volume appears to be a sensitive substitute for response evaluation in osteosarcoma.
Pediatr Radiol (2011) 41:441–450 DOI 10.1007/s00247-010-1876-3 Received: 21 June 2010 / Revised: 4 September 2010 / Accepted: 4 October 2010 / Published online: 27 October 2010
