[Use of EUS-FNA in the diagnosis of hilar schwannoma:a case report].

Upon abdominal ultrasonography, a woman in her 36 years old was diagnosed with a hypoechoic tumor with a diameter of 60mm surrounding the bile duct in the hepatic portal region. Abdominal computed tomography and magnetic resonance cholangiopancreatography revealed a tumor-like mass in the bile duct. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) confirmed the diagnosis of schwannoma. Considering the lesion location, it appeared to rise from the hepatoduodenal ligament. She was unwilling to undergo tumor resection;however, a year after the diagnosis, no change was observed in the tumor. Here, we report a case of schwannoma in the hepatoduodenal ligament, wherein EUS-FNA was useful for establishing a diagnosis and determining a treatment strategy.