Se. Kilpatrick et al., MYXOID CHONDROSARCOMA (CHORDOID SARCOMA) OF BONE - A REPORT OF 2 CASES AND REVIEW OF THE LITERATURE, Cancer, 79(10), 1997, pp. 1903-1910
BACKGROUND. Chondrosarcoma of bone is a well recognized, relatively co
mmon clinicopathologic entity. Morphologically distinct soft tissue ch
ordoid sarcoma (CS), or extraskeletal myxoid chondrosarcoma, is a rela
tively rare tumor that has generally been documented in extraosseous s
oft tissues. METHODS, The clinical and pathologic features of two pati
ents with biopsy-proven CS from the pathology files of the Mayo Clinic
and St. Thomas's Hospital were evaluated. Routine hematoxylin and eos
in-stained slides were reviewed in both cases. Sections from both were
examined immunohistochemically using the avidin-biotin-peroxidase tec
hnique and employing commercially available antibodies to the followin
g antigens: S-100 protein, cytokeratin (AE1/AE3), epithelial membrane
antigen (EMA), CD31, and factor VIII. Appropriate positive and negativ
e controls were utilized throughout these procedures. Cytogenetic anal
ysis was performed on fresh samples obtained from one tumor. Clinical
data were obtained from the patients' medical records. RESULTS. The tw
o cases of primary CS of bone arose from the right distal femur and ri
ght scapula, respectively, in 2 men ages 48 and 76 years, respectively
Morphologically, the tumors were lobulated, multinodular, and compris
ed of a uniform population of rounded to slightly spindled cells. Nucl
ei were hyperchromatic with inconspicuous nucleoli and surrounded by c
lear, vacuolated to eosinophilic cytoplasm. Neoplastic cells were arra
nged in anastomosing chords, strands, and, less often, nests and pseud
opapillary structures embedded in an abundant, mostly hypovascular, mu
cinous matrix. Foci of hemorrhage and cystic degeneration were present
in both tumors. No well developed hyaline cartilage or neoplastic ost
eoid was observed. Immunohistochemically, one neoplasm showed focal po
sitivity for S-100 protein but was uniformly negative for cytokeratin
(AE1/AE3), factor VIII, and CD31. The other tumor showed no immunoposi
tivity with cytokeratin, EMA, or S-100 protein. Cytogenetic analysis i
n the latter tumor revealed a nonrandom reciprocal chromosomal translo
cation, t(9;22)(q22-31; q11-12). Both patients developed local recurre
nces and widespread distant metastases. Wide surgical excision was the
primary mode of therapy. One patient died of tumor. CONCLUSIONS, Skel
etal CS is an extraordinarily rare neoplasm with a distinct morphology
. Although follow-up data were limited to only four examples, includin
g two from the literature, the clinical course appears worse than that
for usual chondrosarcoma of bone. Wide surgical resection appears to
represent the best mode of therapy. The role of chemotherapy and radia
tion therapy has not been clearly defined. (C) 1997 American Cancer So
ciety.