Phenotypic plasticity and prognostic factors in extraskeletal myxoid chondrosarcoma.

Extraskeletal myxoid chondrosarcoma (EMC) is an intriguing entity with a broad morphologic spectrum that overlaps features found in other benign and malignant mesenchymal tumors. This phenotypic plasticity should be known to avoid erroneous diagnosis. The identification of older age, larger tumor size, proximal tumor location, and metastatic disease as independent adverse predictors of survival is useful in achieving optimal treatment and follow-up in high-risk patients.