Validation of American Joint Committee on Cancer 8th edition of TNM staging in resected distal pancreatic cancer

Portomesenteric venous contact ≤180° and overall survival in resectable head and body pancreatic adenocarcinoma treated with upfront surgery

INTRODUCTION

Upfront surgery is the standard of care for resectable pancreatic cancer, defined as the absence of or ≤180° tumour contact with the portal/superior mesenteric vein. We hypothesized that portomesenteric venous tumour contact is prognostically unfavourable and aimed to assess whether it is associated with poorer survival compared with no venous contact in resectable head and body pancreatic cancer.

METHODS

This single-centre retrospective study included patients undergoing upfront surgery for resectable head and body pancreatic cancer in 2010-2020 at Umeå University Hospital, Sweden. No venous contact was compared with portomesenteric venous contact of ≤180° based on preoperative imaging. Overall survival on an intention-to-treat basis was compared with Kaplan-Meier curves, a log-rank test and Cox proportional hazards models.

RESULTS

The final study cohort included 39 patients with portomesenteric venous tumour contact and 144 patients without venous tumour contact. Patients with venous tumour contact had a median overall survival of 15.3 months compared to 23.0 months (log rank P = 0.059). Portomesenteric venous tumour contact was an independent negative prognostic factor for survival in the multivariable Cox model (HR 1.68; 95% CI 1.11-2.55, P = 0.014) and was associated with higher rates of microscopically non-radical resections (R1) (50% vs 26.1%, P = 0.012) and pathological lymph node metastasis (76.7% vs 56.8%, P = 0.012). There was no difference in adjuvant chemotherapy receipt or postoperative complications between the groups.

CONCLUSIONS

Portomesenteric venous tumour contact is associated with poorer overall survival and higher rates of R1 resections and lymph node metastasis in patients with resectable head and body pancreatic cancer treated with upfront surgery.

A new staging system for postoperative prognostication in pancreatic ductal adenocarcinoma

The current TNM staging system for pancreatic ductal adenocarcinoma (PDAC) has revised the definitions of T and N categories as well as stage groups. However, studies validating these modifications have yielded inconsistent results. The existing TNM staging system in prognostic prediction remains unsatisfactory. The prognosis of PDAC is closely associated with pathological and biological factors. Herein, we propose a new staging system incorporating distant metastasis, postoperative serum levels of CA19-9 and CEA, tumor size, lymph node metastasis, lymphovascular involvement, and perineural invasion to enhance the accuracy of prognosis assessment. The proposed staging system exhibited a strong correlation with both overall survival and recurrence-free survival, effectively stratifying survival into five distinct tiers. Additionally, it had favorable discrimination and calibration. Thus, the proposed staging system demonstrates superior prognostic performance compared to the TNM staging system, and can serve as a valuable complementary tool to address the limitations of TNM staging in prognostication.

The prognostic significance of duodenal wall invasion in pancreatic adenocarcinoma

OBJECTIVE

The most recent edition of the American Joint Committee on Cancer Staging Manual (AJCC, 8th edition) relies only on tumor size for staging resectable pancreatic adenocarcinoma, and the presence of duodenal wall invasion (DWI) no longer has an impact on staging. However, very few studies have evaluated its significance. In this study, we aim to evaluate the prognostic significance of DWI in pancreatic adenocarcinoma.

METHODS

We reviewed 97 consecutive internal cases of resected pancreatic head ductal adenocarcinoma, and clinicopathologic parameters were recorded. All cases were staged according to the 8th edition of AJCC, and the patients were divided into two groups based on the presence or absence of DWI.

RESULTS

Out of our 97 cases, 53 patients had DWI (55%). In univariate analysis, DWI was significantly associated with lymphovascular invasion and lymph node metastasis (AJCC 8th edition pN stage). In univariate analysis of overall survival, age > 60, absence of DWI, and African American race were associated with worse overall survival. In multivariate analysis, age > 60, absence of DWI, and African American race were associated with worse progression-free survival and overall survival.

CONCLUSION

Although DWI is associated with lymph node metastasis, it is not associated with inferior disease-free/overall survival.

Pyroptosis regulators exert crucial functions in prognosis, progression and immune microenvironment of pancreatic adenocarcinoma: a bioinformatic and in vitro research

Pyroptosis is an inflammatory programmed cell death, showing potentials to be a novel anti-cancer approach. However, the roles of pyroptosis-related (PR) genes (PRGs) in pancreatic adenocarcinoma (PAAD) remain elusive. In the present study, we constructed a novel PR risk signature through the lasso regression analysis. The risk signature was greatly conducive to PAAD prognostic assessment. PR risk score was identified as an independent prognostic factor and could distinguish the prognostic differences of most clinical subgroups. Meanwhile, it could improve the traditional prognostic models based on TNM-staging. Next, its prognostic value was also tested in five validation cohorts. Using CIBERSORT, ESTIMATE, and ssGSEA algorithms, the effects of PR risk signature on tumor immune microenvironment (TIM) were explored. High PR risk suppressed antitumor immune through decreasing the infiltrating levels of CD8 T and NK cells. The genomic information and histological expression of risk PRGs were uncovered by USCA and HPA databases. Somatic mutation, methylation alteration, and homozygous CNV of eight PRGs barely occurred in PAAD samples. As for therapeutic correlation, PR risk score may not predict the efficacy of PD-1/L1 inhibitors and was weakly associated with multiple drug susceptibilities. Finally, the biofunctions of toll like receptor 3 (TLR3) in pancreatic cancer (PC) cells were investigated through qPCR, MTT, colony formation, and Transwell assays. Overexpression of TLR3 could promote the proliferation, migration, and invasion of PC cells. In conclusion, PRGs play crucial roles in prognosis, progression, and immune microenvironment of PAAD. TLR3 is expected to be a promising therapeutic target.