Diagnostic challenges in hepatic metastatic olfactory neuroblastoma: a case report and literature review.

[BACKGROUND] Olfactory neuroblastoma (ONB) is a rare malignant tumor arising from the nasal cavity and paranasal sinuses, often presenting diagnostic challenges due to its potential for recurrence and distant metastasis, particularly to uncommon sites such as the liver.

[CASE PRESENTATION] We report the case of a 42-year-old female with a history of ONB who was admitted after a liver mass was detected during routine examinations at another hospital two months earlier. The lesion was initially misdiagnosed as primary hepatocellular carcinoma based on imaging findings from contrast-enhanced ultrasound, enhanced CT, and MRI, which revealed a focal lesion in liver segments S5/6. Laboratory results showed slightly elevated AFP (8.91 ng/ml) and CA19-9 (37.12 U/ml), with no other significant abnormalities. The patient subsequently underwent open liver resection.

[RESULTS] Postoperative pathological examination revealed a malignant small round blue cell tumor. Histomorphological and immunohistochemical findings, in conjunction with the patient's clinical history, confirmed the diagnosis of hepatic metastasis from ONB.

[CONCLUSION] Hepatic metastasis of ONB can closely mimic primary liver cancer on imaging, underscoring the necessity of integrating comprehensive clinical history, imaging assessment, and pathological confirmation to avoid misdiagnosis.