J Korean Orthop Assoc.  2022 Aug;57(4):300-306. 10.4055/jkoa.2022.57.4.300.

The Clinical Outcome of Extraskeletal Myxoid Chondrosarcoma

• Kong CB
• Kim KH
• Nam HS
• Song WS
• Koh JS
• Cho WH

• KMID: 2532411
• DOI: http://doi.org/10.4055/jkoa.2022.57.4.300

Abstract

Purpose
Extraskeletal myxoid chondrosarcoma (EMC) is an extremely rare malignant mesenchymal neoplasm, accounting for less than 3% of soft tissue sarcomas. This sarcoma is usually characterized by its indolent course. This study examined the clinical manifestations and oncologic outcomes of EMC.
Materials and Methods
Seventeen patients diagnosed and treated for EMC between January 2008 and December 2018 were enrolled in this study. The cohort was then reviewed regarding age, gender, symptom onset, tumor location, magnetic resonance images, surgical margin, and pathologic diagnosis. The time to local recurrence and metastasis, follow-up duration, and the patients’ final status were analyzed.
Results
The patients were comprised of 10 males and seven female patients with a mean age of 54 (range, 31–79). The tumor location was the buttock in five, thigh in four, knee in three, foot in three, shoulder in one, and back in one. The average tumor diameter was 11.5 cm (range, 2.2–23.2 cm). At the time of diagnosis, five patients were American Joint Committee on Cancer stage II; three were IIIA; three were IIIB; six were IV. Local recurrence occurred in 12 cases, and distant metastasis occurred in 15 cases. The five-year overall survival of the patients with EMC was 73%±17%, and two patients died of the disease.
Conclusion
Despite the high rate of local recurrence and distant metastasis, the long-term survival rate in patients with EMC is quite high because of its indolent characteristics.

Keyword

extraskeletal myxoid chondrosarcoma; pathology; prognosis; indolent