Cytomorphology of intraductal oncocytic papillary neoplasm of the liver

Abstract

We describe the first cytology case report of an intraductal oncocytic papillary neoplasm (IOPN) of the liver. A 51-year-old male presented with recurrent cholangitis. Magnetic resonance imaging and endoscopic retrograde cholangiopancreatogram revealed a 1.1 × 0.9 cm polypoid lesion within the left intrahepatic bile duct. Fine-needle aspiration and needle core biopsy (NCB) revealed nests, 3-dimensional or papillary clusters of columnar or cuboidal cells with loss of polarity. The nuclei were uniform with even chromatin, and cytoplasm was granular or vacuolated. No mitosis or necrosis was seen. The cytologic and histologic diagnosis was "consistent with Intraductal Oncocytic Papillary Neoplasm (IOPN), intermediate grade (borderline)." The patient then underwent a left lateral liver segmentectomy. Microscopic examination showed histology similar to the NCB with no stromal invasion identified. Hepatic IOPN poses a diagnostic challenge due to its broad differential diagnoses. Both malignant and non-malignant IOPNs may present with similar clinical symptoms, pathology, histology, cytomorphology, and immunohistochemistry. Hepatic IOPN should be excised as it is a precursor lesion of adenocarcinoma.

Cytopathologic diagnosis of oncocytic type intraductal papillary mucinous neoplasm: Criteria and clinical implications of accurate diagnosis

“…Although the cytologic features of IPMNs are well established, 15,18-21 the cytologic features of IOPNs (oncocytic-type IPMNs) are described only rarely and mainly in isolated reports. 19,[21][22][23] This is probably related in part to the rarity of the entity, but it is also somewhat attributable to a lack of recognition, which we hope the current study will alleviate to some degree. It is noteworthy that, among the 21 IOPNs we encountered, only 5 had documented FNABs, but this may have been because many of these patients were from an era when pancreatic FNAB was not as common.…”

“…Although the cytologic features of IPMNs are well established, the cytologic features of IOPNs (oncocytic‐type IPMNs) are described only rarely and mainly in isolated reports . This is probably related in part to the rarity of the entity, but it is also somewhat attributable to a lack of recognition, which we hope the current study will alleviate to some degree.…”

Bile duct involvement by hepatocellular carcinoma: A rare occurrence and poor prognostic indicator in bile duct brushing samples

“…However, mixed HCC‐cholangiocarcinoma may be impossible to distinguish from pure HCC in BDBs and may require examination of a larger sample. Other intraductal neoplasms that may demonstrate eosinophilic cells similar to those of HCC include intraductal papillary neoplasm of the bile duct, particularly the oncocytic type, and oncocytic‐type intraductal papillary mucinous neoplasm of the pancreas, which may involve the biliary tree . Both are characterized by papillary units lined by oncocytic cells with large nuclei, prominent nucleoli, and little if any cytoplasmic mucin.…”