Intrapancreatic distal common bile duct carcinoma: Analysis, staging considerations, and comparison with pancreatic ductal and ampullary adenocarcinomas

Abstract

Distal common bile duct carcinoma (DCBDC) is a poorly characterized entity, for reasons such as variable terminology and difficulty in determining site of origin of intrapancreatic lesions. We compared clinicopathologic features of pancreatobiliary-type adenocarcinomas within the pancreas but arising from the distal common bile duct (CBD) (defined as tumors centered around and circumferentially involving the intrapancreatic CBD) with those of pancreatic and ampullary origin. Upon careful review of 1017 pancreatoduodenectomy specimens with primary adenocarcinoma, 52 (5.1%) qualified as intrapancreatic DCBDC. Five associated with an intraductal papillary neoplasm were excluded; the remaining 47 were compared to 109 pancreatic ductal adenocarcinomas (PDAC) and 133 pancreatobiliary-type ampullary adenocarcinomas (AC). DCBDC patients had a younger median age (58 years) than PDAC patients (65 years) and AC patients (68 years). DCBDC was intermediate between PDAC and AC with regard to tumor size and rates of lymph node metastases and margin positivity. Median survival was better than for PDAC (P=0.0010) but worse than for AC (P=0.0006). Microscopically, DCBDC often formed an even band around the CBD and commonly showed intraglandular neutrophil-rich debris and a small tubular pattern. Poor prognostic indicators included lymph node metastasis (P=0.0010), lymphovascular invasion (P=0.0299), and margin positivity (P=0.0069). Categorizing the tumors based on size also had prognostic relevance (P=0.0096), unlike categorization based on anatomic structures invaded (P=0.1575). Primary DCBDC is seen in younger patients than PDAC or AC and has a prognosis significantly better than PDAC and worse than AC, at least partly due to differences in clinical presentation. Use of size-based criteria for staging appears to improve its prognostic relevance. When identified through careful dissection of pancreatoduodenectomy specimens, invasive pancreatobiliary-type DCBDC are uncommon in the West (5% of primary carcinomas in pancreatodudoenectomies) and have substantial clinicopathologic differences from their counterparts arising from the pancreas and ampulla.

Whipple Made Simple For Surgical Pathologists

“…We classify a lesion as primary CBD origin (rather than a pancreatic ductal carcinoma) only if the bulk of the lesion is circumferentially around the CBD as documented grossly and proved microscopically with proper sampling. In our experience, 38 only 5% of the PDs in the West contain such tumors; however, this is much more common in Asia.…”

Pancreatic Ductal Adenocarcinoma is Spread to the Peripancreatic Soft Tissue in the Majority of Resected Cases, Rendering the AJCC T-Stage Protocol (7th Edition) Inapplicable and Insignificant: A Size-Based Staging System (pT1: ≤2, pT2: >2–≤4, pT3: >4 cm) is More Valid and Clinically Relevant

“…Unusual pancreatic adenocarcinoma variants such as colloid were excluded as well as nonductal tumors (acinar, neuroendocrine, pancreatoblastoma, solid pseudopapillary tumors) and secondary cancers (e.g., ampullary, CBD cancers) using stringent criteria. 19,20 …”

Proposed Modification of Staging for Distal Cholangiocarcinoma Based on the Lymph Node Ratio Using Korean Multicenter Database

“…When classified by the AJCC 7th edition, 159 patients (67.7%) were classified as T3. The median TLNC and PLNC were 18 (1-64) and 2 (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17), and the median LNR values obtained by using these two values were 0.11 (0.02-1.00). In the 7th AJCC classification, 78 patients were classified as N1.…”

“…Cholangiocarcinoma (CCC) is a malignant disease that occurs along the biliary tract and is known to constitute 3% of all gastrointestinal cancers [1]. Distal cholangiocarcinoma (DCC) refers to CCC that occurs from the point where the cystic duct joins the common hepatic duct to the ampulla of Vater [2].…”