STAGING OF PRIMARY MUSCULOSKELETAL TUMORS USING WHOLE BODY MRI

Abstract

Introduction and Aims: The aim of this study was to evaluate the role of Whole Body MR (WBMR) in the staging of Musculo Skeletal (MSK) tumors, on a premise that a single study might present an alternative to the traditional imaging.

Method: Forty-two patients were referred for MR evaluation for primary bone or soft tissue sarcomas. These studies were done between October 2001 and April 2003. Each patient had a WBMR, Localised MR, CXR and CT Thorax, and bone scan.

Results: In 42 patients screened, 32 had a primary malignant musculo skeletal tumor. There were 14 primary bone tumors and 18 soft tissue sarcomas. Of the 32 patients concordance between WBMR imaging and the other staging modalities was identified in 27 patients. Discordance was identified in five patients. Two lesions were identified on WBMR and not seen on other imaging modalities. Two lesions not identified by WBMR, subsequently seen on CT thorax. One lesion was not seen on WBMR but seen on localised MR. Eight of the 32 patients had pulmonary metastases. In these patients concordance between the WBMR and CT Thorax was identified in five of eight patients and discordance was identified in three of eight patients where nodules were identified on CT Thorax and not on WBMR. Four patients were noted to have osseous metastases, all seen on WBMR. One bone scan failed to pick up metastasis seen on WBMR. One patient was identified as having a soft tissue metastasis on Whole Body MR, which was not identified on the conventional CT Thorax.

Case studies:

Case 1: Metastatic Leiomyosarcoma

Case 2: Metastatic Ewings sarcoma

Case 3: Metastatic Epithelioid sarcoma

Conclusion: Whole body MR Scanning techniques allow whole body imaging in as little as eight minutes. It is a useful technique in staging and assessing total tumor burden, but still should be performed in conjunction with a CT Thorax.