Published online Jul 21, 2015. doi: 10.3748/wjg.v21.i27.8452
Peer-review started: October 29, 2014
First decision: November 14, 2014
Revised: December 2, 2014
Accepted: January 16, 2015
Article in press: January 16, 2015
Published online: July 21, 2015
Pancreatic metastases are uncommon. They have been reported in lung cancer, gastrointestinal malignancies, breast cancer, renal cell carcinoma, melanoma, lymphoma and sarcoma, and usually have solid morphology. Cystic metastasis to the pancreas is even more rare with few case reports in the literature. However, with the increasing use of computed tomography and magnetic resonance imaging as well as endoscopic ultrasound, more such lesions may be detected. Metastasis to the pancreas from osteosarcoma is highly unusual, but can be seen with the increasing survival of patients with osteosarcoma. We present an extremely rare case of a predominantly cystic lesion of the pancreas, which was diagnosed as metastasis from osteosarcoma. The pathophysiology of the cystic component of the metastasis of osteosarcoma is unknown. Cystic necrotic degeneration of the solid metastasis or pancreatitis secondary to the metastasis with development of associated fluid collection can be considered. Metastasis should remain a differential consideration even for primarily cystic lesions of the pancreas.
Core tip: Cystic pancreatic lesions are more commonly recognized and diagnosed with developing imaging technologies. Metastasis to the pancreas from osteosarcoma is unusual, but has been reported in terms of solid pancreatic masses. This case report shows that metastasis should remain in the differential diagnosis even for primarily cystic pancreatic lesions.