Synchronous intracholecystic papillary-tubular neoplasm and pancreatic intraductal tubulopapillary neoplasm: A case report

Table 1 Clinicopathological comparison between intracholecystic papillary-tubular neoplasm and intraductal tubulopapillary neoplasm[4,6-12]

Feature	ICPN	ITPN
Age/sex tendency	Usually older adults; female predominance	Usually older adults; slight male predominance
Gross/imaging pattern	Polypoid or mass-forming intraluminal gallbladder lesion; may coexist with gallbladder wall thickening or suspected gallbladder cancer	Solid or mixed solid-cystic intraductal pancreatic mass; ductal dilatation may be present, and the lesions may mimic other pancreatic cystic neoplasms
Histological architecture	Papillary, tubular, or tubulopapillary architecture; heterogeneous epithelial lineages may include biliary, gastric, intestinal, and oncocytic phenotypes	Back-to-back tubules, cribriform or abortive papillary structures, high-grade cytology, and minimal or absent mucin
Dysplasia/invasion	Low- or high-grade dysplasia; invasive carcinoma may be present, but resected ICPN often has more a favorable prognosis than conventional gallbladder cancer	High-grade dysplasia is characteristic; invasive carcinoma is common in resected series, but prognosis after resection is generally better than that of conventional pancreatic ductal adenocarcinoma
Immunophenotype	Variable according to lineage; biliary-type lesions often express CK7 and MUC1, gastric-type lesions may express MUC5AC/MUC6, and intestinal-type lesions may express CDX2/CK20	Typically MUC1 and MUC6 positive, MUC2 negative, and MUC5AC absent or limited
Molecular features	Heterogeneous; reported alterations include KRAS, STK11, CTNNB1, APC, TP53, and lineage-associated changes	KRAS/GNAS alterations are uncommon, whereas PI3K pathway alterations, chromatin-remodeling alterations, FGFR2 fusions, and rare ALK fusions have been reported
Clinical implication	Surgical resection is recommended when feasible; if invasive carcinoma is present, management should follow gallbladder cancer principles and pathologic stage	Surgical resection is recommended when feasible; the invasive component, margin status, nodal status, and recurrence risk should guide surveillance

ICPN: Intracholecystic papillary-tubular neoplasm; ITPN: Intraductal tubulopapillary neoplasm; CK7: Cytokeratin 7; CK20: Cytokeratin 20; MUC1: Mucin 1; MUC5AC: Mucin 5AC; CDX2: Caudal type homeobox 2; PI3K: Phosphatidylinositol 3-kinase; FGFR2: Fibroblast growth factor receptor 2; ALK: Anaplastic lymphoma kinase.