Primary duodenal extraskeletal osteosarcoma-a case report

Abstract

Extraskeletal osteosarcoma is a rare malignant soft tissue tumour, which represents about 4% of all osteosarcomas and 1% of all soft tissue sarcomas. We present a case of extraskeletal osteosarcoma, albeit at a hitherto undescribed site, duodenum. This case report addresses the clinicopathological features and differential diagnosis of extraskeletal osteosarcoma and the importance of clinicopathological correlation in the diagnosis and workup of such cases.

Pancreatic Extraskeletal Osteosarcoma Metastasizing to the Scalp

“…Immunohistochemical analyzes would be helpful in these entities to make a differential diagnosis. Positivity for CD99, vimentin, osteonectin, and osteocalcin as well as negativity for cytokeratin, CD34, and S100 support the diagnosis of ESOSs 7 . CD99 is the most sensitive marker that is expressed in all types of osteosarcoma and MDM-2 can also be useful in distinguishing a low-grade ESOS from a benign lesion.…”

“…There have been few reported cases of ESOS in the literature with only 300 cases reported since it was first described by Wilson in 1941 1 8 . Although the lower extremities and retroperitoneum are common sites, ESOSs have been reported in other organs such as the larynx, esophagus, breast, liver, duodenum, kidney, urinary bladder, orbit, and skin 1 4 5 7 10 . However, a pancreatic ESOS has not yet been reported in the literature.…”

“…Over 70% patients experience local recurrence and metastasis. The overall 5-year survival is reported to range from 25% to 77% and patients with metastatic lesions have a morality rate over 60% 3 7 . In one case series, the median survival time was measured as 8 months for metastatic ESOSs with doxorubicin-based chemotherapy 8 .…”

“…Trauma and radiation therapy are well-known predisposing factors in the development of around 10% ESOS patients 5 . It clinically manifests as a painless lesion in the lower extremities, most commonly occurring in the muscles of the thigh followed by the retroperitoneum and upper limb 1 6 7 . The lung is the most common site for the metastasis of ESOS followed by the regional lymph nodes 3 8 .…”