Erdheim-Chester disease is a rare and challenging case to diagnose. It shows multi-systemic/organic involvement. Therefore, diagnosis is based on histological and radiological findings.

As in this case, there are multiple findings involving the orbit, manifested by bilateral intraconal soft tissue mass lesions, retroperitoneal or perirenal infiltrative soft tissue thickening and bony sclerosis. When the radiological findings are taken separately, there will be many differential diagnoses.

Lymphoma will be on top of the differential diagnosis because it contains most of these radiological findings.

Additional Contributors:

Dr. Asem Mansour, Consultant Radiologist. Chief Executive Officer/Director General, King Hussein Cancer Center(KHCC), Amman, Jordan.

Dr. Hussain Ali Aby Ali, Consultant Radiologist, Tawam hospital, United Arab Emirates.