Intraductal Papillary Adenocarcinoma Of The Bile Duct With Associated Invasive Neuroendocrine Component: Case Report

Casestudy Intraductal papillary neoplasm of the bile duct (IPNB) is a variant of bile duct carcinoma that is characterized by intraductal growth and better outcomes compared with common cholangiocarcinoma. IPNBs are mainly found in patients from Far Eastern countries, where hepatolithiasis and clonorchiasis are endemic. Approximately 40%-80% of IPNBs are associated with invasive carcinoma. The invasive carcinomas are most often tubular or mucinous type. Invasive neuroendocrine component has not been previously described. We present a case of 69 year-old African American male who presented with worsening abdominal pain and jaundice over few months. Computed tomography showed 4 cm mass near the porta hepatis with massive ductal dilatation. A fine needle aspiration of the mass was performed and a diagnosis of adenocarcinoma was made. Subsequently, the patient underwent Right Trisegmentectomy. Conclusion Histologic sections revealed intraductal papillary neoplasm in the bile duct lumina. The papillae were lined by columnar epithelial cells with delicate fibrovascular cores. The tumor cell nuclei were slightly elongated, hyperchromatic and basally located without significant multilayering. The cytoplasm was eosinophilic with occasional intestinal differentiation. Frank invasion of the stalk and underlying periductular tissues was identified. Interestingly; the invasive component had different cytological features than the intraductal component, it was composed of small to medium sized cells with granular cytoplasm. The nuclei were uniform and round with “salt and pepper” chromatin. The invasive component stained positively for the neuroendocrine markers (Synaptophysin, Chromogranin and CD56), whereas the intraductal component stained positively for CK7, CK20 and CDX2 and negative for neuroendocrine markers. Three years later, a recurrent tumor was found in the left lobe on imaging. Biopsy of the lesion showed metastatic neuroendocrine carcinoma. The intraductal papillary neoplasm with invasive neuroendocrine component is very unusual tumor, we think more studies are warranted to best evaluate the treatment options and the prognosis of such neoplasms.