Pancreatic ductal adenocarcinoma and distal cholangiocarcinoma: a proposal of preoperative diagnostic score for differential diagnosis

Preoperative prognostic stratification and prediction of long-term outcomes after pancreatoduodenectomy for distal cholangiocarcinoma

BACKGROUND

Patients with distal cholangiocarcinoma (DCC) frequently receive adjuvant chemotherapy in preoperative and postoperative settings, but prediction of prognostic risk at the time of treatment selection remains challenging.

METHODS

This single-center retrospective study enrolled DCC patients who underwent initial pancreatoduodenectomy (PD) between 2009 and 2022. Preoperative clinical parameters were collected, and Cox regression analysis was used to identify risk factors for overall survival (OS).

RESULTS

Among 170 patients examined, the median tumor depth was 10 mm, and 37 % of the patients were diagnosed with pT3. Overall, 46 % of patients had lymph node metastasis. The median and 5-year OS was 58.2 months and 50 %, respectively. Multivariate analysis revealed tumor size on computed tomography (CT) ≥15 mm and main pancreatic duct (MPD) dilatation (≥3 mm) as independent risk factors for OS among various preoperative parameters; the prognosis was stratified based on these two parameters. Patients with one risk factor had similar outcomes (5-year OS: 39 %) to pStage IIB DCC (pT2N1 or pT3), while those with two risk factors had a prognosis akin to pStage IIIA (pN2), with a high early recurrence rate of 64 % (5-year OS: 8 %). Among non-risk group patients with low carbohydrate antigen (CA)19-9 levels (<37 U/mL), the prognosis was comparable (5-year OS: 72 %) to those with pStage I DCC.

CONCLUSION

A simple stratification approach was developed to predict long-term postoperative outcomes. To improve poor prognosis, intensive therapy, including neoadjuvant chemotherapy, should be considered for patients with two risk factors.

Cholangiocarcinoma: Pathologic and Molecular Classification in the Era of Precision Medicine

CONTEXT.—

Cholangiocarcinoma (CCA) is a heterogeneous cancer of the bile duct, and its diagnosis is often challenging.

OBJECTIVE.—

To provide insights into state-of-the-art approaches for the diagnosis of CCA.

DATA SOURCES.—

Literature review via PubMed search and authors' experiences.

CONCLUSIONS.—

CCA can be categorized as intrahepatic or extrahepatic. Intrahepatic CCA is further classified into small-duct-type and large-duct-type, whereas extrahepatic CCA is classified into distal and perihilar according to site of origin within the extrahepatic biliary tree. Tumor growth patterns include mass forming, periductal infiltrating, and intraductal tumors. The clinical diagnosis of CCA is challenging and usually occurs at an advanced tumor stage. Pathologic diagnosis is made difficult by tumor inaccessibility and challenges in distinguishing CCA from metastatic adenocarcinoma to the liver. Immunohistochemical stains can assist in differentiating CCA from other malignancies, such as hepatocellular carcinoma, but no distinctive CCA-specific immunohistochemical profile has been identified. Recent advances in next-generation sequencing-based high-throughput assays have identified distinct genomic profiles of CCA subtypes, including genomic alterations that are susceptible to targeted therapies or immune checkpoint inhibitors. Detailed histopathologic and molecular evaluations of CCA by pathologists are critical for correct diagnosis, subclassification, therapeutic decision-making, and prognostication. The first step toward achieving these goals is to acquire a detailed understanding of the histologic and genetic subtypes of this heterogeneous tumor group. Here, we review state-of-the-art approaches that should be applied to establish a diagnosis of CCA, including clinical presentation, histopathology, staging, and the practical use of genetic testing methodologies.

Tumour origin, diagnostic accuracy and histopathological evaluation in patients with periampullary cancer: nationwide cohort study

BACKGROUND

The prevalence of different periampullary cancers (pancreatic ductal adenocarcinoma, distal cholangiocarcinoma, ampullary cancer and duodenal cancer) is heterogeneous in the literature. During the 2010s, a standardized histopathological protocol for pancreatoduodenectomy specimens based on axial slicing was adopted in Sweden. The present study sought to provide information about periampullary cancers with regard to tumour types in curative and noncurative settings, preoperative diagnostic accuracy and the impact of a standardized evaluation of the surgical specimen on diagnosis, R status and lymph node assessment.

METHODS

Data from patients diagnosed with periampullary cancer from 2010 to 2019 were retrieved from the Swedish National Registry for Pancreatic and Periampullary Cancer.

RESULTS

Among non-curative patients, 3704 (83.6 per cent) were diagnosed with pancreatic ductal adenocarcinoma. Among patients treated with pancreatoduodenectomy, diagnosis was pancreatic ductal adenocarcinoma in 1380 (50.0 per cent), distal cholangiocarcinoma in 284 (10.3 per cent), ampullary cancer in 376 (13.6 per cent), duodenal cancer in 160 (5.8 per cent) and other diagnoses in 560 (20.3 per cent) patients. The preoperative diagnosis corresponded to the postoperative in 1177 (67.5 per cent) patients for pancreatic ductal adenocarcinoma, 162 (37.4 per cent) patients for distal cholangiocarcinoma, 220 (61.3 per cent) patients for ampullary cancer and 120 (53.6 per cent) patients for duodenal cancer. A higher rate of pancreatic ductal adenocarcinoma was seen in surgical specimens who underwent standardized evaluation, from 56.8 per cent to 64.3 per cent (P = 0.003). After standardization, higher rates of R1 resection (31.7 per cent versus 44.6 per cent, P < 0.001) and N1 stage (62.1 per cent versus 77.0 per cent, P < 0.001) were found.

CONCLUSION

The proportion of pancreatic ductal adenocarcinoma was higher in patients in a non-curative setting compared with patients who underwent surgery. The rate of misdiagnosis for periampullary cancers was confirmed to be high. Thus, it should be taken into account when preoperative oncological treatment is considered. Standardized evaluation of the surgical specimen has increased pancreatic ductal adenocarcinoma, R1 and N1 rates.

Extrahepatic Distal Cholangiocarcinoma vs. Pancreatic Ductal Adenocarcinoma: Histology and Molecular Profiling for Differential Diagnosis and Treatment

Pancreatic ductal adenocarcinoma (PDAC) and distal cholangiocarcinoma (dCCA) are very aggressive tumors with a high mortality rate. Pancreas and distal bile ducts share a common embryonic development. Hence, PDAC and dCCA exhibit similar histological features that make a differential diagnosis during routine diagnostic practice challenging. However, there are also significant differences, with potential clinical implications. Even if PDAC and dCCA are generally associated with poor survival, patients with dCCA seem to present a better prognosis. Moreover, although precision oncology-based approaches are still limited in both entities, their most important targets are different and include alterations affecting BRCA1/2 and related genes in PDAC, as well as HER2 amplification in dCCA. Along this line, microsatellite instability represents a potential contact point in terms of tailored treatments, but its prevalence is very low in both tumor types. This review aims at defining the most important similarities and differences in terms of clinicopathological and molecular features between these two entities, also discussing the main theranostic implications derived from this challenging differential diagnosis.

Temporal Association of Total Serum Cholesterol and Pancreatic Cancer Incidence

Previous studies have suggested a “cholesterol-lowering effect” of preclinical pancreatic cancer, suggesting lower total cholesterol as a potential diagnostic marker. Leveraging repeated measurements of total cholesterol, this study aims to examine the temporal association of total cholesterol and pancreatic cancer incidence. We conducted a nested case-control study based on a Korean National Health Insurance Service−Health Screening Cohort, including 215 pancreatic cancer cases and 645 controls matched on age and sex. Conditional logistic regression was applied to estimate the odds ratio (OR) and 95% confidence interval (CI) for the associations of pancreatic cancer incidence with total cholesterol levels across different time windows over 11 years before pancreatic cancer diagnosis (recent, mid, distant). We found that, compared to participants with total cholesterol < 200 mg/dL in the recent 3 years prior to diagnosis, those having total cholesterol ≥ 240 mg/dL showed a significantly lower pancreatic cancer incidence (OR = 0.50 (0.27−0.93)). No significant association was found in relation to total cholesterol measured in the mid and distant past. When changes in total cholesterol over the three time periods were analyzed, compared with those with total cholesterol levels consistently below 240 mg/dL over the entire period, the OR of pancreatic cancer was 0.45 (0.20−1.03) for participants with recent-onset hypercholesterolemia, 1.89 (0.95−3.75) for recent-resolved hypercholesterolemia, and 0.71 (0.30−1.66) for consistent hypercholesterolemia. In conclusion, while high total cholesterol in the recent past may indicate a lower pancreatic cancer incidence, a recent decrease in total cholesterol may suggest an elevated incidence of pancreatic cancer.