Intestinal type adenocarcinoma: a previously unrecognized histologic variant of ductal carcinoma of the pancreas

Long-Term Survival in Metastatic Pancreatic Adenocarcinoma of Intestinal Type

Introduction and Literature Review: Pancreatic cancer is often diagnosed in an advanced/metastatic stage, as it is a very aggressive type of cancer. The prognosis of pancreatic cancer is extremely unfavorable. The mean survival rate for patients with metastatic pancreatic adenocarcinoma is 3-6 months. Stage IV pancreatic cancer has a five-year survival rate of 1.3% to 13%. This article presents recent data regarding the oncologic management of metastatic pancreatic cancer. Case presentation: We present the case of a female patient who was 49 years old at the time of diagnosis, in June 2021. The patient was diagnosed with stage IV pancreatic neoplasm (due to liver metastases). The diagnosis was made by histopathological and immunohistochemical examination, which corroborated imaging investigations. The patient underwent four lines of chemotherapy between July 2021 and July 2024, undergoing partial response to the disease. The patient is a long-term survivor of metastatic pancreatic cancer (3 years in July 2024). Discussions: the peculiarity of this case is long-term survival (3 years and a month at the date when this article is being written) in a patient with pancreatic cancer and liver metastases. Conclusions: histopathological type, good performance status, CEA, and CA tumor markers 19.9 within normal limits may be favorable prognostic factors for long-term survival in metastatic pancreatic carcinoma.

Prognostic significance of histologic phenotype in periampullary adenocarcinomas

Background

Periampullary adenocarcinomas typically exhibit either intestinal or pancreatobiliary (PB) differentiation, and the type of differentiation may be prognostically more important than the anatomic site of origin. This study aimed to evaluate prognostic significance of histological type of periampullary carcinomas.

Methods

Microscopic slides from 110 consecutive pancreatoduodenectomies performed between 2010 and 2020 were reviewed and classified as intestinal or PB type. Clinicopathological factors were compared between PB-(n=93) and intestinal-type (n=17) differentiation.

Results

The intestinal type included significantly more patients with well-differentiated histology (35.3% vs. 11.8%, p=0.001) and fewer patients with perineural invasion (41.2% vs. 76.4%, p=0.029), advanced T stage (> T3; 41.2% vs.74.2%, p=0.007), and systemic recurrence (71.4% vs. 92.9%, p=0.005) than PB type. The 5-year-overall survival rate of intestinal-type was significantly higher than that of PB-type (58.8% vs. 20.4%, p=0.003). When pancreatic cancer was separately analyzed, the intestinal type showed the best 5-year-overall survival rate, with no significant difference between the PB types excluding PDAC and PDAC (39.4% vs. 19.2%, p=0.148). In multivariate analysis, curative resection (hazard ratio, 0.417; 95% CI, 0.219-0.792, p=0.008) was the only significant prognostic factor.

Conclusion

Although intestinal histologic phenotype was not an independent prognostic factor on multivariate analysis, it showed pathologic features associated with better survival, while the PB type showed more aggressive tumor biology and consequently worse survival. Further studies are needed to demonstrate the prognostic significance of histologic phenotype.

Multi-omics analysis of intra-tumoural and inter-tumoural heterogeneity in pancreatic ductal adenocarcinoma

The poor prognosis of pancreatic ductal adenocarcinoma (PDAC) is associated with the tumour heterogeneity. To explore intra- and inter-tumoural heterogeneity in PDAC, we analysed the multi-omics profiles of 61 PDAC lesion samples, along with the matched pancreatic normal tissue samples, from 19 PDAC patients. Haematoxylin and Eosin (H&E) staining revealed that diversely differentiated lesions coexisted both within and across individual tumours. Whole exome sequencing (WES) of samples from multi-region revealed diverse types of mutations in diverse genes between cancer cells within a tumour and between tumours from different individuals. The copy number variation (CNV) analysis also showed that PDAC exhibited intra- and inter-tumoural heterogeneity in CNV and that high average CNV burden was associated poor prognosis of the patients. Phylogenetic tree analysis and clonality/timing analysis of mutations displayed diverse evolutionary pathways and spatiotemporal characteristics of genomic alterations between different lesions from the same or different tumours. Hierarchical clustering analysis illustrated higher inter-tumoural heterogeneity than intra-tumoural heterogeneity of PDAC at the transcriptional levels as lesions from the same patients are grouped into a single cluster. Immune marker genes are differentially expressed in different regions and tumour samples as shown by tumour microenvironment (TME) analysis. TME appeared to be more heterogeneous than tumour cells in the same patient. Lesion-specific differentially methylated regions (DMRs) were identified by methylated DNA immunoprecipitation sequencing (MeDIP-seq). Furthermore, the integration analysis of multi-omics data showed that the mRNA levels of some genes, such as PLCB4, were significantly correlated with the gene copy numbers. The mRNA expressions of potential PDAC biomarkers ZNF521 and KDM6A were correlated with copy number alteration and methylation, respectively. Taken together, our results provide a comprehensive view of molecular heterogeneity and evolutionary trajectories of PDAC and may guide personalised treatment strategies in PDAC therapy.

Immunohistochemical profiling of liver metastases and matched-pair analysis in patients with metastatic pancreatic ductal adenocarcinoma

BACKGROUND

The purpose of the current study was to investigate the immunohistochemical (IHC) profile of liver metastases (LM) in patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

Expression of 15 IHC markers in liver biopsies from 77 patients with PDAC, who were diagnosed between 2010 and 2014, were evaluated. In a separate subgroup analysis (n = 12), paired samples (LM and primary tumor) from the same patient were investigated for IHC profile differences.

RESULTS

LM samples were classified as pancreatobiliary-type (PB-type) in 72 patients (93.5%), intestinal-type (INT-type) in four patients (5.2%), and squamous in one patient (1.3%). There was no significant difference in overall survival (OS) between LM of the PB-type or INT-type (p = 0.097). In a multivariate analysis, age <70 years (p = 0.047), absence of SMAD4 mutation (p = 0.026), absence of CDX2 expression (p = 0.003), and well to moderate differentiation were significant prognostic factors for better OS in patients with LM (p = 0.031). Analysis of paired tissue samples from LM and the primary tumor revealed a difference in CDX2 (50% increase, p = 0.125) and SMAD4 (33% loss of SMAD4, p = 0.375).

CONCLUSIONS

CDX2 expression and SMAD4 mutation indicate a poor outcome in patients with LM of PDAC. Matched-pair analysis revealed differences in distinct IHC marker expression.

High-grade precursor lesions can be used as surrogate markers to identify the epicenter of periampullary carcinomas

Identifying the accurate origin of periampullary cancers is important because different origins may trigger different clinicopathological behaviors. The presence of intraepithelial precursor lesions, including high-grade pancreatic intraepithelial neoplasias (PanINs) and/or high-grade biliary intraepithelial neoplasias (BilINs), may be suggestive of the origin of the periampullary carcinoma in challenging cases. To prove the usefulness of high-grade intraepithelial precursor lesions in identifying the origin of ambiguous periampullary cancers, the status and grades of PanINs and BilINs were evaluated in 256 periampullary carcinomas with a well-defined cancer origin as a test set, including 114 pancreatic cancers, 82 distal bile duct cancers, 54 ampullary cancers, and 6 duodenal cancers. One hundred twelve periampullary carcinomas with clinically equivocal epicenter either by radiologic imaging or by endoscopic finding used as a validation set. High-grade PanINs were found more commonly in pancreatic cancers than in distal bile duct, ampullary, and duodenal cancers both in test (P = .002) and validation sets (P < .001). Similarly, high-grade BilINs were identified more frequently in distal bile duct cancers than in ampullary, pancreatic, and duodenal cancers both in test (P < .001) and validation sets (P = .039). High-grade PanINs were found most commonly in pancreatic cancers, whereas high-grade BilINs were seen most frequently in distal bile duct cancers. In addition, both high-grade PanINs and high-grade BilINs are uncommonly noted in ampullary or duodenal cancers. The recognition of high-grade intraepithelial lesions can help identify the primary origin of periampullary cancers, especially when the epicenter of the periampullary cancer is ambiguous.

Immunohistochemical Typing of Adenocarcinomas of the Pancreatobiliary System Improves Diagnosis and Prognostic Stratification

BACKGROUND & AIMS

Adenocarcinomas of the pancreatobiliary system are currently classified by their primary anatomical location. In particular, the pathological diagnosis of intrahepatic cholangiocarcinoma is still considered as a diagnosis of exclusion of metastatic adenocarcinoma. Periampullary cancers have been previously classified according to the histological type of differentiation (pancreatobiliary, intestinal), but overlapping morphological features hinder their differential diagnosis. We performed an integrative immunohistochemical analysis of pancreato-biliary tumors to improve their diagnosis and prediction of outcome.

METHODS

This was a retrospective observational cohort study on patients with adenocarcinoma of the pancreatobiliary system who underwent diagnostic core needle biopsy or surgical resection at a tertiary referral center. 409 tumor samples were analyzed with up to 27 conventional antibodies used in diagnostic pathology. Immunohistochemical scoring system was the percentage of stained tumor cells. Bioinformatic analysis, internal validation, and survival analysis were performed.

RESULTS

Hierarchical clustering and differential expression analysis identified three immunohistochemical tumor types (extrahepatic pancreatobiliary, intestinal, and intrahepatic cholangiocarcinoma) and the discriminant markers between them. Among patients who underwent surgical resection of their primary tumor with curative intent, the intestinal type showed an adjusted hazard ratio of 0.19 for overall survival (95% confidence interval 0.05-0.72; p value = 0.014) compared to the extrahepatic pancreatobiliary type.

CONCLUSIONS

Integrative immunohistochemical classification of adenocarcinomas of the pancreatobiliary system results in a characteristic immunohistochemical profile for intrahepatic cholangiocarcinoma and intestinal type adenocarcinoma, which helps in distinguishing them from metastatic and pancreatobiliary type adenocarcinoma, respectively. A diagnostic immunohistochemical panel and additional extended panels of discriminant markers are proposed as guidance for their pathological diagnosis.

Morphological heterogeneity in ductal adenocarcinoma of the pancreas - Does it matter?

Morphological heterogeneity is a common finding in pancreatic ductal adenocarcinoma. Inter- and intra-tumour heterogeneity relates not only to the microscopic appearances of the tumour cell population, but pertains also to other essential aspects of the cancer, including the grade of differentiation, growth pattern and desmoplastic stroma. While the existence of considerable morphological variation is well known among pathologists, it is usually not fully appreciated by the wider community. Morphological heterogeneity in pancreatic cancer is only partially represented in the WHO classification, and current pathology guidelines do not recommend reporting on morphological variation other than the conventional variants of ductal adenocarcinoma. Although tumour heterogeneity is increasingly recognized as a major determinant of therapeutic response, morphological heterogeneity has been left unconsidered as a possible proxy for underlying aberrations - genomic or otherwise - that determine the effect of treatment. Various aspects of morphological heterogeneity in pancreatic ductal adenocarcinoma are illustrated in this article and discussed along with the possible implications for patient management and research.

Molecular signatures of mRNAs and miRNAs as prognostic biomarkers in pancreatobiliary and intestinal types of periampullary adenocarcinomas

Periampullary adenocarcinomas include four anatomical sites of origin (the pancreatic duct, bile duct, ampulla and duodenum) and most of them fall into two histological subgroups (pancreatobiliary and intestinal). Determining the exact origin of the tumor is sometimes difficult, due to overlapping histopathological characteristics. The prognosis depends on the histological subtype, as well as on the anatomical site of origin, the former being the more important. The molecular basis for these differences in prognosis is poorly understood. Whole-genome analyses were used to investigate the association between molecular tumor profiles, pathogenesis and prognosis. A total of 85 periampullary adenocarcinomas were characterized by mRNA and miRNA expressions profiling. Molecular profiles of the tumors from the different anatomical sites of origin as well as of the different histological subtypes were compared. Differentially expressed mRNAs and miRNAs between the two histopathological subtypes were linked to specific molecular pathways. Six miRNA families were downregulated and four were upregulated in the pancreatobiliary type as compared to the intestinal type (P < 0.05). miRNAs and mRNAs associated with improved overall and recurrence free survival for the two histopathological subtypes were identified. For the pancreatobiliary type the genes ATM, PTEN, RB1 and the miRNAs miR-592 and miR-497, and for the intestinal type the genes PDPK1, PIK3R2, G6PC and the miRNAs miR-127-3p, miR-377* were linked to enriched pathways and identified as prognostic markers. The molecular signatures identified may in the future guide the clinicians in the therapeutic decision making to an individualized treatment, if confirmed in other larger datasets.

Pathology reporting of pancreatic cancer following neoadjuvant therapy: challenges and uncertainties

An increasing number of studies investigate the use of neoadjuvant treatment for ductal adenocarcinoma of the pancreas. While a strong rationale supports this approach, study results are difficult to interpret and compare due to marked variance in multiple aspects of study design and performance. Divergence in pathology examination and reporting as a cause for heterogeneity and incomparability of study results has not been brought into this discussion yet, despite the fact that several key outcome measures for neoadjuvant treatment are pathology-based. This article discusses areas of controversy and difficulty regarding the evaluation of the extent of residual tumour tissue, grading of tumour regression and assessment of the margins, and explains the important clinical implications of the present uncertainty and divergence in pathology practice.

Generation and characterisation of novel pancreatic adenocarcinoma xenograft models and corresponding primary cell lines

Pancreatic adenocarcinoma is one of the most lethal cancer types, currently lacking efficient treatment. The heterogeneous nature of these tumours are poorly represented by the classical pancreatic cell lines, which have been through strong clonal selection in vitro, and are often derived from metastases. Here, we describe the establishment of novel pancreatic adenocarcinoma models, xenografts and corresponding in vitro cell lines, from primary pancreatic tumours. The morphology, differentiation grade and gene expression pattern of the xenografts resemble the original tumours well. The cell lines were analysed for colony forming capacity, tumourigenicity and expression of known cancer cell surface markers and cancer stem-like characteristics. These primary cell models will be valuable tools for biological and preclinical studies for this devastating disease.

Ampullary cancer--a separate clinical entity?

AIMS

Ampullary cancer is a relatively uncommon tumour, with a better prognosis than pancreatic cancer. The purpose of this study was to review the recent literature on ampullary adenocarcinoma, focusing on histological types and prognostic factors.

METHODS AND RESULTS

Using PubMed, we carried out a comprehensive search of the literature, which was extended to April 2013 to retrieve all additional publications. Ampullary cancer comprises two main histological subtypes, the pancreatobiliary type and the intestinal type. These subtypes have different pathogenetic and clinical characteristics. Clinical and histological parameters as well as immunohistochemical markers have been identified as significant prognostic factors in ampullary cancer. Moreover, several immunohistochemical markers have been studied, not only as prognostic factors but as a means of differentiating ampullary from other peri-ampullary tumours, and of identifying the exact histological subtype.

CONCLUSIONS

The considerable differences in the frequencies of the two subtypes of ampullary tumours reported in literature reinforce the necessity to define molecular markers to distinguish them. Until then, the significance of the histological subtype as a prognostic factor should be evaluated cautiously. Future research on the pathogenesis of ampullary cancer will possibly suggest that we should stop treating this type of cancer as a separate entity.

Intestinal-type of differentiation predicts favourable overall survival: confirmatory clinicopathological analysis of 198 periampullary adenocarcinomas of pancreatic, biliary, ampullary and duodenal origin

Background

Periampullary adenocarcinomas comprise pancreatic, distal bile duct, ampullary and duodenal adenocarcinoma. The epithelia of these anatomical structures share a common embryologic origin from the foregut. With steadily increasing numbers of pancreatoduodenectomies over the last decades, pathologists, surgeons and oncologists are more often confronted with the diagnosis of “other than pancreatic” periampullary cancers. The intestinal subtype of ampullary cancer has been shown to correlate with better prognosis.

Methods

Histological subtype and immunohistochemical staining pattern for CK7, CK20 and CDX2 were assessed for n = 198 cases of pancreatic ductal, distal bile duct, ampullary and duodenal adenocarcinoma with clinical follow-up. Routine pathological parameters were included in survival analysis performed with SPSS 20.

Results

In univariate analysis, intestinal subtype was associated with better survival in ampullary, pancreatic ductal and duodenal adenocarcinoma. The intestinal type of pancreatic ductal adenocarcinoma was not associated with intraductal papillary mucinous neoplasm and could not be reliably diagnosed by immunohistochemical staining pattern alone. Intestinal differentiation and lymph node ratio, but not tumor location were independent predictors of survival when all significant predictor variables from univariate analysis (grade, TNM stage, presence of precursor lesions, surgical margin status, perineural, vascular and lymphatic vessel invasion, CK7 and CDX2 staining pattern) were included in a Cox proportional hazards model.

Conclusions

Intestinal type differentiation and lymph node ratio but not tumor location are independent prognostic factors in pooled analysis of periampullary adenocarcinomas. We conclude that differentiation is more important than tumor location for prognostic stratification in periampullary adenocarcinomas.

Intestinal-type and pancreatobiliary-type adenocarcinomas: how does ampullary carcinoma differ from other periampullary malignancies?

BACKGROUND

Ampullary carcinomas typically have either intestinal or pancreatobiliary type of differentiation, histopathologically resembling carcinomas of its adjacent tissues (duodenum, bile duct, or pancreas). We evaluated whether the histologic type itself is more important for long-term survival than the fact that the tumor originated in the ampulla.

METHODS

Microscopic slides from 207 consecutive pancreatoduodenectomies were reviewed (72 pancreatic, 46 biliary, 61 ampullary, and 28 duodenal adenocarcinomas; 76 intestinal type, 131 pancreatobiliary type). Tumor size, nodal involvement, margin involvement, degree of differentiation, vascular involvement, and perineural growth, as well as overall survival, were compared between different origins of the same histologic type.

RESULTS

Intestinal-type ampullary adenocarcinomas had similar frequency of poor histopathologic factors compared to duodenal adenocarcinomas, and pancreatobiliary-type ampullary adenocarcinomas had similar frequency of poor histopathologic factors compared to pancreatobiliary-type biliary and pancreatic adenocarcinomas. Adjusting for tumor size and nodal involvement, there was no difference in long-term survival between patients with intestinal-type ampullary, duodenal, or biliary and pancreatic tumors (p = 0.79), and there was no difference in long-term survival between patients with pancreatobiliary-type ampullary, biliary, or pancreatic tumors (p = 0.41).

CONCLUSIONS

Long-term survival for patients with ampullary carcinomas equals pancreatic, biliary, and duodenal carcinomas when the same histologic type is compared. It can be questioned whether ampullary carcinomas should be regarded as a separate entity in classification of solid tumors. Clinical trials on adjuvant treatments for periampullary carcinomas should stratify by pancreatobiliary type versus intestinal type of histologic differentiation.

Gastric- and intestinal-type marker expression in invasive ductal adenocarcinoma of the pancreas

BACKGROUND

Although invasive ductal adenocarcinoma of the pancreas (PDAC) manifests as a relatively uniform histomorphological feature of the pancreatobiliary type, it may be complicated by metaplastic changes and heterogeneous gastric and intestinal elements. This study aimed to investigate the complication rate and clinicopathological significance of such heterogeneous elements.

METHODS

Fifty-nine patients who underwent resection of PDAC were examined in this study. Immunohistochemically, tumors showing high expression (>25%) of the intestinal-type (INT) marker CDX2 were classified as PDAC with INT. Those with high expression (>25%) of the gastric-type (GAS) marker MUC5AC were classified as PDAC with GAS, while those with high expression of both markers were classified as PDAC with INT/GAS. These patients were compared with those with PDAC of the negative group in which neither markers was highly expressed to examine their clinicopathological significance.

RESULTS

In the 59 patients, 31 (52.5%) showed high CDX2 or MUC5AC expression. Twenty-eight patients (47.5%) belonged to a negative group, 11 (18.6%) to a PDAC with INT group, 15 (25.4%) to a PDAC with GAS group, and 5 (8.5%) to a PDAC with INT/GAS group. No significant differences were observed for age, gender, size, localization, T classification, or prognosis among the four groups. Although the PDAC with GAS group had well differentiated types significantly more than the other groups, the rate of lymph node metastasis in this group was significantly higher (PDAC with GAS: 73%; other groups: 36%).

CONCLUSION

Complications with heterogeneous elements are not uncommon in PDAC, and this should be considered during the diagnosis and treatment of PDAC along with histogenesis of the disease.

Early gallbladder carcinoma: a clinicopathologic study of 13 cases of intramucosal carcinoma

We report the clinicopathologic features of 13 cases of intramucosal carcinoma (IMC) of the gallbladder. All IMCs were incidental findings in cholecystectomy specimens for cholelithiasis. However, one of the patients had a carcinoma of the pancreas, and the gallbladder incidentally removed during the Whipple procedure showed an IMC. Another patient had a small cell carcinoma of the gallbladder, and one of the sections showed an IMC. Of the IMCs, 10 were well-differentiated adenocarcinomas, 1 was a moderately differentiated adenocarcinoma, 1 was an undifferentiated carcinoma, and 1 was a squamous cell carcinoma. Of the patients, 8 were disease-free from 3 to 11 years, and 2 patients died, one as a result of the pancreatic ductal carcinoma and the other with disseminated metastases of the small cell carcinoma. The follow-up of another patient was too short to be significant. Two patients were lost to follow-up. Our findings suggest that a simple cholecystectomy is a curative procedure for IMCs of the gallbladder.

The role of Cdx2 in Barrett's metaplasia

Metaplasia (or transdifferentiation) is defined as the transformation of one tissue type to another. Clues to the molecular mechanisms that control the development of metaplasia are implied from knowledge of the transcription factors that specify tissue identity during normal embryonic development. Barrett's metaplasia describes the development of a columnar/intestinal phenotype in the squamous oesophageal epithelium and is the major risk factor for oesophageal adenocarcinoma. This particular type of cancer has a rapidly rising incidence and a dismal prognosis. The homoeotic transcription factor Cdx2 (Caudal-type homeobox 2) has been implicated as a master switch gene for intestine and therefore for Barrett's metaplasia. Normally, Cdx2 expression is restricted to the epithelium of the small and large intestine. Loss of Cdx2 function, or conditional deletion in the intestine, results in replacement of intestinal cells with a stratified squamous phenotype. In addition, Cdx2 is sufficient to provoke intestinal metaplasia in the stomach. In the present paper, we review the evidence for the role of Cdx2 in the development of Barrett's metaplasia.

Cancers of the ampulla of vater: demographics, morphology, and survival based on 5,625 cases from the SEER program

BACKGROUND

Cancers of the ampulla are unusual and morphologically heterogeneous. The NCI's SEER Program is now large enough so that unusual cancers can be studied. Based on pathologic and epidemiologic characteristics of cancer of the ampulla available in SEER, important clinicopathological correlations can be made.

METHODS

All patients with cancer of the ampulla were identified between 1973 and 2005. Demographic features, distribution of histological types, age-specific incidence rates, and 5-year survival rates according to stage and histologic type were compared.

RESULTS

There were 5,625 cases of ampullary cancer. Ampullary cancer has been increasing since 1973. In both African Americans and Caucasians, the disease is more common in men. Adenocarcinomas, NOS comprised 65% of all histological types. Survival depends on stage, grade, and histologic type. Papillary carcinomas had a more favorable survival than other types; carcinomas arising in adenomas had a more favorable survival than adenocarcinomas not associated with adenomas. Logarithmic transformation of age-related incidence data demonstrates that cancers having differing histopathologic phenotypes represent a single population of tumors.

CONCLUSIONS

Prognostic factors include histologic type, grade, stage, and coexisting adenomas. These data should be included in pathology reports. Although certain histologic types exhibit morphologic differences, their pathogenesis appears to be similar.

Cdx genes, inflammation and the pathogenesis of Barrett's metaplasia

Metaplasia is the conversion of one cell or tissue type to another and can predispose patients to neoplasia. Perhaps one of the best-known examples of metaplasia is Barrett's metaplasia (BM), a pathological condition in which the distal oesophageal epithelium switches from stratified squamous to intestinal-type columnar epithelium. BM predisposes to oesophageal adenocarcinoma and is the consequence of long-term acid bile reflux. The incidence of BM and oesophageal adenocarcinoma has risen dramatically in recent years. A key event in the pathogenesis of BM is the induction of oesophageal CDX2 expression. Importantly, recent data reveal the molecular mechanisms that link inflammation in the development of Barrett's metaplasia, CDX2 and the progression to cancer. This review highlights the relationship between inflammation, metaplasia and carcinogenesis.

Differentiation markers in pancreatic head adenocarcinomas: MUC1 and MUC4 expression indicates poor prognosis in pancreatobiliary differentiated tumours

Aims:

To examine how accurately immunohistochemical markers discriminate between pancreatobiliary and intestinal-type adenocarcinomas in the pancreatic head and to explore the prognostic importance of these markers among each of these histological types.

Methods and results:

Histopathological features of 114 consecutively resected adenocarcinomas of pancreatobiliary (n = 67) and intestinal (n = 47) type of differentiation were recorded according to a standardized protocol. Immunohistochemistry for cytokeratin (CK) 7, CK20, MUC1, MUC2, MUC4 and CDX2 was performed on tissue microarrays. Classification of the adenocarcinomas based on immunohistochemistry was compared with the morphological evaluation of histological type. Presence of CK7 and MUC4, and absence of CDX2, were independent predictors of pancreatobiliary versus intestinal type. Using these markers to optimize immunohistochemical classification, agreement between immunohistochemical and morphological classification was only moderate (κ = 0.53). In pancreatobiliary differentiated tumours, MUC1 and/or MUC4 expression was an independent prognostic factor (hazard ratio 2.02, 95% confidence interval 1.02, 3.98) when adjusting for nodal involvement, vessel involvement and tumour size. In intestinally differentiated tumours, none of the markers was significantly associated with prognosis.

Conclusions:

Agreement between immunohistochemical and morphological classification of pancreatic head adenocarcinomas is moderate. In pancreatobiliary adenocarcinomas, MUC1 and/or MUC4 expression indicates a particularly poor prognosis.

Carcinomas of the pancreas, gallbladder, extrahepatic bile ducts, and ampulla of vater share a field for carcinogenesis: a population-based study

CONTEXT

Carcinomas co-occur in the pancreas, extrahepatic bile ducts, and ampulla of Vater. We investigated whether cancers originating in these sites represent a field effect similar to that observed in the lung and upper aerodigestive tract.

OBJECTIVE

To determine whether a field effect for carcinogenesis exists in the ampulla of Vater, extrahepatic bile ducts, gallbladder, and pancreas.

DESIGN

Data were obtained from National Cancer Institute's Surveillance Epidemiology and End Results Program from 1973 through 2005. Cases were compared by age frequency density plots, age-specific incidence rates, and logarithmic plots of the age-specific incidence rates and age of diagnosis.

RESULTS

Incidence rates were 11.71, 1.43, 0.88, and 0.49 per 100,000 persons at risk for pancreatic, gallbladder, extrahepatic bile ducts, and ampullary carcinomas, respectively. Age frequency density plots were congruent for cancers originating in all 4 sites. Logarithmic plots of the age-specific incidence rates with age of diagnosis produced parallel linear rate patterns for the 4 sites indicative of similar populations for tumor development. However, density and logarithmic plots of pancreatic endocrine carcinomas, a tumor of different cellular differentiation and carcinogenic pathway, served as a comparison. The endocrine carcinomas showed a different age distribution and nonparallel rate patterns with ductal carcinomas.

CONCLUSIONS

Carcinomas of the pancreas, gallbladder, extrahepatic bile ducts, and ampulla have a common embryonic cellular ancestry, differentiation pathways, mucosal histologic patterns, and population-related tumor development indicating a field effect in carcinogenesis. Parallel linear rate patterns indicate (1) the rate of cancer development is similar in all 4 sites even though the absolute incidence rates vary and (2) regardless of location, the ductal epithelium is equally susceptible to malignant transformation. If carcinogenic pathways to cancer are similar, then the different incidence rates seen clinically may depend on the relative surface area of the ductal system in these sites. Pancreatic cancers are most common because the surface area of the pancreas' ductal system is greater than that of the gallbladder, extrahepatic bile ducts, and ampulla.

Cribriform carcinoma of the gallbladder: a clinicopathologic study of 7 cases

Carcinomas of the gallbladder are morphologically heterogeneous. Some are similar or mimic carcinomas that commonly arise in other organs and therefore can be confused with metastatic lesions. We report here the clinicopathologic features of 7 cribriform carcinomas of the gallbladder that resemble cribriform carcinomas of the breast. Five patients were women and 2 men whose ages ranged from 31 to 72 years (average age 57 y). These 7 patients were younger than those with conventional adenocarcinomas of the gallbladder (average age for males 71 y and average age for females 72 y). Five patients had cholelithiasis. The youngest patient, a 31-year-old woman, had no gallstones. Instead, she had an osteosarcoma removed from her distal femur, 4 years before. Although the osteosarcoma in this patient may be coincidental, a true association could not be entirely excluded. None of the 4 cribriform carcinomas of the gallbladder tested showed immunoreactivity for estrogen and progesterone receptors. Three patients with high nuclear grade cribriform carcinomas died as a result of the tumor which infiltrated the liver by direct extension; 3 patients with low nuclear grade cribriform carcinomas confined to the gallbladder wall survived 4 to 7 years after cholecystectomy and 1 patient was lost to follow-up. In conclusion, this study provides support to previous observations that a small proportion of gallbladder carcinomas display an unusual but predominant cribriform pattern similar to that of some invasive breast carcinomas. In contrast to mammary cribriform carcinomas, those arising in the gallbladder occur in individuals usually with gallstones, may coexist with skeletal osteosarcoma, lack estrogen and progesterone receptors, and behave aggressively like conventional adenocarcinomas of the gallbladder.

Pancreatobiliary versus intestinal histologic type of differentiation is an independent prognostic factor in resected periampullary adenocarcinoma

BACKGROUND

Resectable adenocarcinomas in the pancreatic head, by definition "periampullary", originate from ampullary, duodenal, biliary, or ductal pancreatic epithelium. Typically, periampullary adenocarcinomas have either intestinal or pancreatobiliary type of differentiation, and the type of differentiation might be prognostically more important than the anatomic site of origin. The aim of the study was to determine whether the histologic type of differentiation is an independent prognostic factor in periampullary adenocarcinoma, and whether tumour origin predicts the prognosis in pancreatobiliary type carcinomas independently of resection margin involvement, tumour size, nodal involvement, perineural and vascular infiltration, and degree of differentiation.

METHODS

Histopathologic variables in 114 consecutively resected periampullary adenocarcinomas of pancreatobiliary (n = 67) and intestinal (n = 47) type differentiation were evaluated using a standardized, systematic protocol for evaluation of the resected specimen (study group). Histologic type of differentiation and tumour origin were compared as predictors of survival, and the results were validated by comparison with a historical control group consisting of 99 consecutive pancreaticoduodenectomies performed before standardization of histopathologic evaluation. Associations between histopathologic variables were evaluated by Chi-square and Mann-Whitney tests. Survival was estimated by the Kaplan-Meier method, comparing curves using log-rank test, and by univariate and multivariable Cox regression analysis.

RESULTS

Both in the study group (n = 114) and in the historical control group (n = 99), the histologic type of differentiation independently predicted survival, while tumour origin predicted survival only in univariate analysis. Independent adverse predictors of survival in the study group were pancreatobiliary type differentiation (p < 0.001; HR 3.1; CI 1.8-5.1), regional lymph node involvement (p < 0.001; HR 2.5; CI 1.5-4.4), vessel involvement (p = 0.012; HR 1.9; CI 1.2-3.1), and increasing tumour diameter (measured in cm, p = 0.011; HR 1.3; CI 1.1-1.5). For pancreatobiliary differentiated adenocarcinomas (n = 67), lymph node status, vessel involvement, and tumour diameter remained independent prognostic factors, while tumour origin did not independently predict the prognosis due to significant association with tumour size (p < 0.001) and lymph node involvement (p = 0.004).

CONCLUSION

Pancreatobiliary versus intestinal type of differentiation independently predicts poor prognosis after pancreaticoduodenectomy for periampullary adenocarcinoma. Lymph node involvement, vessel infiltration, and increasing tumour diameter are adverse predictors of survival in tumours with pancreatobiliary differentiation.