P2009 - Ampullary Mixed Adenoneuroendocrine Carcinoma Surprising as Abdominal Pain

Michael Tran, MD, John Green, DO, Chad Spencer, MD, Vindhya Bellamkonda, MD, Pallavi Patil, MD, Kurt Knowles, MD, William Sonnier, MD
University of South Alabama Health Systems, Mobile, AL

Introduction: Ampullary Mixed Adenoneuroendocrine Carcinoma (MANEC) is a rare, heterogeneous malignancy with under 25 cases reported in the literature. Symptoms, treatment and prognosis of ampullary MANEC are not well defined. We present a case of ampullary MANEC to add to the literature.

Case Description/Methods: A 72-year-old female with history of hypothyroidism presented with abdominal pain after undergoing liver biopsy for elevated alkaline phosphatase (ALP) and negative serologies. Physical exam revealed right upper quadrant tenderness. An increase in total bilirubin from 1.0 to 14.3 mg/dL and ALP from 390 to 943 IU/L was noted. MRCP revealed intra and extrahepatic biliary ductal dilation. Liver biopsy demonstrated normal hepatic parenchyma with cholestatic changes. ERCP revealed an enlarged major papilla with deep, malignant-appearing ulcerations and a CBD stricture with upstream dilation to 1.5 cm. Placement of a fully covered metal stent achieved decompression. Ampullary biopsies demonstrated invasive adenocarcinoma; however, subsequent pancreaticoduodenectomy revealed a 2.1 cm mixed adenocarcinoma-neuroendocrine carcinoma (60% adenocarcinoma, 40% neuroendocrine carcinoma) with nodal involvement. Adjuvant cisplatin and etoposide was begun with favorable response.

Discussion: MANEC has been described throughout the GI tract, but ampullary cases are exceedingly rare. While scattered neuroendocrine cells in adenocarcinoma is common, MANECs are defined as neoplasms in which neuroendocrine components make up at least 30% of the tumor.¹ Non-surgical diagnosis of ampullary MANEC is difficult due to a lack of specific symptoms and radiological findings; in addition, most cases are mistaken for routine adenocarcinoma on endoscopic biopsies, as in this case.² For resectable tumors, pancreaticoduodenectomy is recommended, with many receiving adjuvant chemotherapy. Chemotherapy regimen may be tailored to treat the most aggressive component of the tumor, judged to be neuroendocrine in our case.² The complexity of diagnosis and management of ampullary MANECs emphasizes the importance of a multidisciplinary approach to care.

1. Rindi G, Klimstra DS, Arnold, R. Nomenclature and classification of neuroendocrine neoplasms of the digestive system. WHO classification of tumors of the digestive system. 2010; 13-14.

2. Mahansaria SS, Agrawal N, Arora A, et al. Ampullary mixed adenoneuroendocrine carcinoma: surprise histology, familiar management. Int J Surg Pathol. 2017; 25(7):585-591.





Figure: MANEC Histology and mass
a. Left superior - adenocarcinoma component, rt inferior - neuroendocrine component
b. Left superior - adenocarcinoma component, rt inferior - neuroendocrine component
c. Ampullary mass seen on ERCP


Disclosures:
Michael Tran indicated no relevant financial relationships.
John Green indicated no relevant financial relationships.
Chad Spencer indicated no relevant financial relationships.
Vindhya Bellamkonda indicated no relevant financial relationships.
Pallavi Patil indicated no relevant financial relationships.
Kurt Knowles indicated no relevant financial relationships.
William Sonnier indicated no relevant financial relationships.


Michael Tran, MD, John Green, DO, Chad Spencer, MD, Vindhya Bellamkonda, MD, Pallavi Patil, MD, Kurt Knowles, MD, William Sonnier, MD. P2009 - Ampullary Mixed Adenoneuroendocrine Carcinoma Surprising as Abdominal Pain, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.