Orbital metastasis as the primary manifestation of pancreatic carcinoma: a case report and literature review

BACKGROUND: Orbital metastasis from pancreatic tumors is extremely rare, and its clinical characteristics are still unclear. CASE PRESENTATION: Our case was a 73-year-old female who noticed diplopia on right gaze 3 months before referral to us. Imaging studies demonstrated a mass involving the lateral rectus muscle in the right orbit. The results of pathological examination of an excised specimen corresponded to poorly differentiated adenocarcinoma. Systemic work-up revealed pancreatic carcinoma with peritoneal metastasis. The patient underwent chemotherapy. We reviewed literature on similar cases and found 19 reported cases of pancreatic tumors metastasizing to the orbit. The results of our review indicate a tendency for formation of solitary mass without bony erosion, delayed detection of the primary pancreatic carcinoma, and poorer prognosis of such tumors, compared to metastatic orbital tumors from other lesions. CONCLUSIONS: We report a rare case of metastatic orbital tumor from an unknown primary pancreatic carcinoma. Clinical characteristics of cases with metastatic pancreatic tumors seem to be different from those with metastatic tumors from the other lesions. Pancreatic tumors are frequently asymptomatic in an early stage, leading to delayed detection of the primary pancreatic carcinoma and poorer prognosis.