Osteosarcoma: MR imaging after preoperative chemotherapy.

Abstract

The authors reviewed 76 magnetic resonance (MR) images of 38 patients with osteosarcoma treated with preoperative chemotherapy (intraarterial cisplatin with or without systemic chemotherapy). Histologic maps of the surgical tumor specimens in 33 cases were correlated with either late-chemotherapy or postchemotherapy MR images. There were four MR patterns--dark, mottled or speckled, homogeneous, and cystic--that corresponded to different amounts of tumor matrix, granulation tissue, hemosiderin deposits, fluid-filled cysts, and residual viable tumor. Nested foci of residual viable tumor could not be specifically identified, although tumor progression or skip metastases were accurately depicted in four patients. Other findings included (a) peritumoral edema in the soft tissues and intramedullary space that shrank with chemotherapy, (b) chemotherapy effect in the surrounding soft tissues, (c) a dark rim around the extramedullary component of the tumors corresponding to a collagenous capsule continuous with the periosteum, (d) development of metaphyseal hemorrhages and bone marrow infarcts, and (e) intramedullary vascular channels.

Dynamic contrast‐enhanced MR imaging evaluation of osteosarcoma response to neoadjuvant chemotherapy

“…However, this method requires both quantitative T2 values and phosphorus MR spectroscopy assessment of pH; the latter MR spectroscopic technique is not yet widely available (18). =-weighted MR imaging has been used to monitor tumor response but cannot clearly differentiate necrosis from viable tumor, and residual tumor foci do not have specffic MR imaging features (19). In addition, T1-weighted contrast-enhanced MR imaging overestimates the extent of viable tumor because of nonmalignant reactive tissue enhancement (1 1).…”

Prostaglandin levels of primary bone tumor tissues correlate with peritumoral edema demonstrated by magnetic resonance imaging

“…Keller et al investigated the effect of local PGE 2 on the periosteum in rabbits, and vestigated as an indicator of chemotherapeutic responses. [22][23][24] The reaction has recently been observed showed a primitive periosteal-woven bone with thin trabeculae in a richly vascularized connective tissue more dramatically in some benign bone tumors rather than malignant tumors. 5 -7,9 However, the mechanism after local PGE 2 infusion.…”

Prognostic Value of Tc-99m-MIBI Performed During Middle Course of Preoperative Chemotherapy in Patients With Malignant Bone and Soft-Tissue Tumors

“…Both imaging, especially MRI can evaluate various phenomena during tumor regression such as necrosis, hemorrhage, development of granulation tissue, fibrosis etc. [26][27][28][29] For the direct assessment of tumor viability, dynamic contrast enhanced MRI could be more precise method, 30 because it can provide information about tissue perfusion, capillary permeability and hence tumor viability. However, in our knowledge, there is no systematic study whether dynamic MRI has significant value for the assessment of tumor response to preoperative chemotherapy and potential prognostic value.…”