[99] Chondrosarcomas: Skip Metastasis

W-L Wang, NJ Hilliard, MT Deavers, VO Lewis, AK Raymond. University of Texas MD Anderson Cancer Center, Houston, TX

Background: Skip metastases (mets) in chondrosarcoma (ChS) are exceedingly rare. However, their recognition is important as they may be missed by radiologists and pathologists and thereby complicate complete tumor removal.
Design: Five cases of ChS with skip mets were retrieved from the pathology files of our institution. The time frame was 1985-2008 and there were a total of over 700 ChS resections. Clinical and radiological information were reviewed. Skip mets were defined as tumors occurring away from the primary tumor in the same site and separated by either normal bone (i.e., intra-medullary skip met) or an articular surface (i.e., transarticular skip met).
Results: The mean age at presentation was 55 years (range: 33 - 77 years). There were 4 males and 1 female. No patient (pt) had a history of multiple enchdromatosis. The majority of primary tumors occurred in the femur (n=4), one tumor arose in the acetabulum. All pts had intra-medullary skip mets. The mean size of the primary tumor was 14 cm (range: 9 - 19.6 cm). Three cases were dedifferentiated ChS. Two cases were conventional ChS, grade 3/3. Four pts had a single skip met. One pt had multiple skip mets within a single bone. The mean size of skip mets was 8.8 mm (range: 1.0 - 25.0 mm) with the mets separated from the primary tumors by 3.6 - 9.0 mm. Two pts died of disease (7 and 50 months); both of these pts had local relapse and lung mets. One of these pts had multiple skip mets. Three pts had no evidence of disease with an average post-operative follow-up of 37 months (range: 24 - 47 months).
Conclusions: Skip mets are exceedingly rare in ChS and can be very small. Although their presence does not necessarily portend a poor prognosis, their recognition is important to assure complete tumor extirpation at the time of definitive surgery for the primary lesion.
Category: Bone & Soft Tissue

Tuesday, March 10, 2009 9:30 AM

Poster Session III # 10, Tuesday Morning