Mesenterico-portal vein invasion should be an important factor in TNM staging for pancreatic ductal adenocarcinoma: Proposed modification of the 8th edition of the American Joint Committee on Cancer staging system

Phenotypic profiling of pancreatic ductal adenocarcinoma plasma-derived small extracellular vesicles for cancer diagnosis and cancer stage prediction: a proof-of-concept study

Circulating pancreatic ductal adenocarcinoma (PDAC) derived small extracellular vesicles (sEVs) are nano-sized membranous vesicles secreted from PDAC cells and released into surrounding body fluids, such as blood. The use of plasma-derived sEVs for cancer diagnosis is particularly appealing in biomedical research because the sEVs reflect some key features (e.g. genetic and phenotypic status) related to the organs from which they originate. For example, the surface membrane proteins and their expression level on sEVs were reported to be related to the presence and progression of PDAC. However, difficulty in sEVs isolation and lack of ultrasensitive assays for simultaneous analysis of multiple protein biomarkers on patient plasma-derived sEVs hinder their application in the clinic. In our previous study, we have demonstrated the application of magnetic beads (MBs) and surface-enhanced Raman scattering (SERS) assay for phenotypic analysis of cancer cells-derived sEVs using different cell lines. To further demonstrate the clinical application of the proposed assay, we have profiled the sEVs' phenotypes (relative expression of biomarker Glypican 1, EpCAM and CD44V6) of healthy donors and PDAC patients to enable simultaneous detection of multiple surface membrane proteins on plasma-derived sEVs. We discovered that the PDAC sEVs' phenotype signatures had high accuracy for PDAC diagnosis (100%) and showed strong correlation with cancer stages, which were further validated by the imaging techniques (e.g. computerized tomography and magnetic resonance imaging) and also the correlation of cancer stages with CA19-9 (gold standard biomarker) and the sEVs' phenotype signatures. The present proof-of-concept study thus provides an initial investigation of using the proposed SERS assay for PDAC diagnosis and early cancer stage prediction in the clinic.

A proposal to modify the 8th edition of the UICC staging system for pancreatic adenocarcinoma

PURPOSE

The aim of this study was to validate and improve the 8th edition of the Union for International Cancer Control (UICC) staging system for pancreatic ductal adenocarcinoma (PDAC).

METHODS

Prognostic impact of the pathological tumor (pT) and lymph node (pN) stages between the 7th and 8th editions were compared using a single-center cohort of 311 patients who underwent curative pancreatic resection for PDAC.

RESULTS

Applying the 7th edition T staging system resulted in a clustering of pT3 cases (92.3%) and failed to show significant prognostic differences between the three pT stages. However, applying the 8th edition T staging system yielded a more even distribution and resulted in an excellent prognostic separation between the pT stages based on decreases in median survival (month [pT1: 69.4, pT2: 27.6, pT3: 16.7], p=0.001). In pN staging system, the 8th edition provided more precise prognostication in median survival (month [pN0: 41.7, pN1: 25.6, pN2: 14.4], p<0.001). Moreover, in the 8th edition pT2 category, patients with portal vein invasion (PVI) showed significantly worse survival than those without PVI (median survival months [without PVI: 38.2, with PVI: 17.1], p<0.001).

CONCLUSIONS

The 8th edition provides a more even distribution among stages and better stage discriminations compared to the 7th edition. The 8th edition pT2 category should be subdivided according to PVI status of the patient to allow for more precise patient prognostication.

Vascular resection during pancreatectomy for pancreatic head cancer: A technical issue or a prognostic sign?

BACKGROUND

There is an increased interest in venous vascular resection associated with pancreatic resection for pancreatic ductal adenocarcinoma as an upfront procedure or after neoadjuvant treatment. The aim of this study was to evaluate the impact of venous vascular resection for pancreatic ductal adenocarcinoma on postoperative and long-term outcomes.

METHODS

The study is a retrospective analysis of patients who underwent pancreatectomy for pancreatic head pancreatic ductal adenocarcinoma with and without venous vascular resection between January 2010 and April 2018. The impact of venous vascular resection on postoperative and pathologic data was analyzed. Univariate and multivariate analyses of predictors of disease-free and disease-specific survival were analyzed for the entire cohort. A propensity-score matched cohort analysis was subsequently performed to remove selection bias and improve homogeneity.

RESULTS

Four hundred and eighty-one patients were included, and 126 (26%) underwent a venous vascular resection. Patients undergoing venous vascular resection had higher morbidity (64% vs 54%; P = .026) with no differences in 90-day postoperative mortality (3.1 vs 2.8%; P = .5). Venous vascular resections were also significantly associated with R1 resections (52% vs 37%; P = .002) and perineural invasion (87% vs 77%; P = .017). Five-year disease-free survival in patients with and without venous vascular resection were 7% and 20% (P = .018), respectively. Independent predictors of worse disease-free survival included venous vascular resection, positive lymph node status, and perineural invasion. Independent predictors of worse disease-specific survival were perineural invasion and positive nodal status, while adjuvant treatment was a protective factor. Five-year disease-specific survival in patients with and without venous vascular resection were 19% and 35% (P = .42).

CONCLUSION

Pancreatectomy with venous vascular resection can be accomplished safely. Venous vascular resections are associated with poor prognostic factors and with a worse clinical outcome, being a significant predictor of cancer recurrence.