Chemotherapy improved prognosis of mesenchymal chondrosarcoma with rare metastasis to the pancreas

Abstract

Extraskeletal mesenchymal chondrosarcoma is rare and metastasis to the pancreas is extremely rare, with only four cases reported in the literature. The therapeutic effectiveness of chemotherapy remains uncertain. We report a 39-year-old man with extraskeletal mesenchymal chondrosarcoma of the buttock, who had metastases to the pancreas, bones, and lung. He underwent distal pancreatectomy, resection of the buttock tumor, and chemotherapy. He had a good response to chemotherapy and survived for about 3 years after surgery.

Figure 1

(a) Abdominal computed tomography, showing a well-circumscribed, low-attenuation, inhomogeneously enhancing mass measuring about 5 cm in diameter in the body and tail of the pancreas. (b) Abdominal computed tomography, showing a well-circumscribed, heterogeneously enhancing mass measuring about 8 cm × 3 cm in the left buttock. (c) Abdominal magnetic resonance imaging, showing a well-circumscribed mass measuring 4.5 cm in diameter in the body and tail of the pancreas. The mass had inhomogeneous enhancement with gadolinium diethylenetriaminepentaacetic acid on T1-weighted fat-suppression images. (d) Magnetic resonance imaging of the lesion in the left buttock, showing an inhomogeneously hyperintense mass on T2-weighted images.

Figure 2

Histological findings of the biopsy specimen of the buttock tumor, showing a poorly differentiated round cell malignant neoplasm, growing in sheets. The tumor cells had scant, pale eosinophilic cytoplasm. Hematoxylin and eosin staining, original magnification ×100 (a) and ×400 (b).

Figure 3

Histological examination of the resected buttock tumor, showing a poorly differentiated round cell malignant neoplasm, growing in sheets. The tumor cells had scant, pale eosinophilic cytoplasm. Hematoxylin and eosin staining, original magnification ×400 (a) and ×200 (b). There were large areas of well-differentiated cartilage, showing focal endochondral ossification ((c), ×40).

Figure 4

(a) Preoperative positron emission tomography, showing areas of increased uptake in the pancreas, left buttock, pelvis, and the thoracic, lumbar, and sacral vertebrae. (b) The areas of increased uptake disappeared after eight cycles of chemotherapy.