Prognosis of pancreatic head cancer with different patterns of lymph node metastasis

The scRNA-sequencing landscape of pancreatic ductal adenocarcinoma revealed distinct cell populations associated with tumor initiation and progression

Pancreatic ductal adenocarcinoma (PDAC) stands as a formidable malignancy characterized by its profound lethality. The comprehensive analysis of the transcriptional landscape holds immense significance in understanding PDAC development and exploring novel treatment strategies. However, due to the firm consistency of pancreatic cancer samples, the dissociation of single cells and subsequent sequencing can be challenging. Here, we performed single-cell RNA sequencing (scRNA-seq) on 8 PDAC patients with different lymph node metastasis status. We first identified the crucial role of MMP1 in the transition from normal pancreatic cells to cancer cells. The knockdown of MMP1 in pancreatic cancer cell lines decreased the expression of ductal markers such as SOX9 while the overexpression of MMP1 in hTERT-HPNE increased the expression of ductal markers, suggesting its function of maintaining ductal identity. Secondly, we found a S100A2 + tumor subset which fueled lymph node metastasis in PDAC. The knockdown of S100A2 significantly reduced the motility of pancreatic cancer cell lines in both wound healing and transwell migration assays. While overexpression of S100A2 led to increased migratory capability. Moreover, overexpression of S100A2 in KPC1199, a mouse pancreatic cancer cell line, caused a larger tumor burden in a hemi-spleen injection model of liver metastasis. In addition, epithelial-mesenchymal transition-related genes were decreased by S100A2 knockdown revealed by bulk RNA sequencing. We also identified several pivotal contributors to the pro-tumor microenvironment, notably OMD + fibroblast and CCL2 + macrophage. As a result, our study provides valuable insights for early detection of PDAC and promising therapeutic targets for combatting lymph node metastasis.

Radiomics-based histological grading of pancreatic ductal adenocarcinoma using 18F-FDG PET/CT: A two-center study

OBJECTIVE

To explore the value of radiomics features derived from 18F-FDG PET/CT images in predicting the histological grade of pancreatic ductal adenocarcinoma (PDAC).

MATERIALS AND METHODS

A retrospective analysis was conducted using data from patients with suspected pancreatic cancer, who histologically confirmed as PDAC within 14 days after 18F-FDG PET/CT scan in one of two hospitals. Tumors were divided into high-grade (undifferentiated or poorly differentiated), and low-grade (moderately or well differentiated). Two researchers independently used uRP to perform layer-by-layer tumor segmentation in both PET and CT images of each patient, and extract features. Model performance was evaluated using 5-fold cross-validation on the entire multi-center cohort, with results averaged across all folds. The least absolute shrinkage and selection was used for feature selection, and support vector machine (SVM), random forest (RF), and logistic regression (LR) were employed to distinguish the grade of PDAC. The performance of the model was evaluated using the receiver operating characteristic curve.

RESULTS

This study comprised 111 patients (72 males and 39 females), comprising 52 patients with high-grade PDAC tumors and 59 patients with low-grade. A series of models were established by SVM, LR, and RF algorithms based on selected features. In the test set, the mean areas under the curve (AUCs) for PET image-based models using SVM, LR, and RF algorithms were 0.773, 0.772, and 0.760. For CT-based models, the mean AUCs were 0.764, 0.770, and 0.576. For PET/CT-based models, the mean AUCs were 0.840, 0.844, and 0.773.

CONCLUSION

Despite the lack of external validation, the PET/CT-derived radiomics model enables accurate preoperative histological grading of PDAC, offering a clinically actionable tool to neoadjuvant therapy stratification and further guide personalized medical decision-making.

Application of imaging technology for the diagnosis of malignancy in the pancreaticobiliary duodenal junction (Review)

The pancreaticobiliary duodenal junction (PBDJ) is the connecting area of the pancreatic duct, bile duct and duodenum. In a broad sense, it refers to a region formed by the head of the pancreas, the pancreatic segment of the common bile duct and the intraduodenal segment, the descending and the horizontal part of the duodenum, and the soft tissue around the pancreatic head. In a narrow sense, it refers to the anatomical Vater ampulla. Due to its complex and variable anatomical features, and the diversity of pathological changes, it is challenging to make an early diagnosis of malignancy at the PBDJ and define the histological type. The unique anatomical structure of this area may be the basis for the occurrence of malignant tumors. Therefore, understanding and subclassifying the anatomical configuration of the PBDJ is of great significance for the prevention and treatment of malignant tumors at their source. The present review comprehensively discusses commonly used imaging techniques and other new technologies for diagnosing malignancy at the PBDJ, offering evidence for physicians and patients to select appropriate examination methods.

Prognostic Significance of 18 F-FDG PET/CT Radiomics in Patients With Resectable Pancreatic Ductal Adenocarcinoma Undergoing Curative Surgery

PURPOSE

This study aimed to investigate the prognostic significance of PET/CT radiomics to predict overall survival (OS) in patients with resectable pancreatic ductal adenocarcinoma (PDAC).

METHODS

We enrolled 627 patients with resectable PDAC who underwent preoperative 18 F-FDG PET/CT and subsequent curative surgery. Radiomics analysis of the PET/CT images for the primary tumor was performed using the Chang-Gung Image Texture Analysis toolbox. Radiomics features were subjected to least absolute shrinkage and selection operator (LASSO) regression to select the most valuable imaging features of OS. The prognostic significance was evaluated by Cox proportional hazards regression analysis. Conventional PET parameters and LASSO score were assessed as predictive factors for OS by time-dependent receiver operating characteristic curve analysis.

RESULTS

During a mean follow-up of 28.8 months, 378 patients (60.3%) died. In the multivariable Cox regression analysis, tumor differentiation, resection margin status, tumor stage, and LASSO score were independent prognostic factors for OS (HR, 1.753, 1.669, 2.655, and 2.946; all P < 0.001, respectively). The time-dependent receiver operating characteristic curve analysis showed that the LASSO score had better predictive performance for OS than conventional PET parameters.

CONCLUSIONS

The LASSO score using the 18 F-FDG PET/CT radiomics of the primary tumor was the independent prognostic factor for predicting OS in patients with resectable PDAC and may be helpful in determining therapeutic and follow-up plans for these patients.

Prognostic significance of lymph node metastasis in pancreatic tail cancer: A multicenter retrospective study

Background

Distal pancreatectomy (DP) with lymph node (LN) dissection is the standard procedure for pancreatic ductal adenocarcinoma of the tail (Pt-PDAC). However, the optimal surgery including extent of LN dissection is still being debated. The present study investigated the incidence and prognostic impact of LN metastasis on patients suffering from Pt-PDAC.

Patients and method

This multicenter, retrospective study involved 163 patients who underwent DP for resectable Pt-PDAC at 12 institutions between 2013 and 2017. The frequency of LN metastasis and the effect of LN dissection on Pt-PDAC prognosis were investigated.

Results

There were high incidences of metastases to the LNs along the splenic artery in the patients with Pt-PDAC (39%). The rate of metastases in the LNs along the common hepatic, left gastric, and celiac arteries were low, and the therapeutic index for these LNs was zero. In pancreatic tail cancer located more distally, there were no metastases to the LNs along the common hepatic artery. Multivariate analysis revealed that tumor size was the only independent factor related to recurrence-free survival (HR = 2.01, 95% CI = 1.33-3.05, p = 0.001). The level of pancreas division and LN dissection along the common hepatic artery did not affect the site of tumor recurrence or recurrence-free survival.

Conclusions

LN dissection along the hepatic artery for Pt-PDAC has little significance. Distal pancreatic transection may be acceptable in terms of oncological safety, but further examination of short-term outcomes and preservation of pancreatic function is required.

Common hepatic artery lymph node metastasis in pancreatic ductal adenocarcinoma: an analysis of actual survival

BACKGROUND

The common hepatic artery lymph node (CHALN) represents a second-echelon node for tumors in the head of the pancreas. Although early studies suggested survival was comparable between the CHALN and remote metastasis in pancreatic ductal adenocarcinoma (PDAC), whether the lymph node is associated with adverse survival remains equivocal. Here, we examined a prospective cohort of patients calculating actual survival to better understand implications of this specific lymph node metastasis.

METHODS

We studied 215 patients with pancreatic head PDAC, who underwent pancreaticoduodenectomies at a single institution between 2010 and 2017, wherein the CHALNs were excised. We performed actual and actuarial overall survival and disease-free survival (DFS) analyses, with subsequent univariate and multivariate analyses in node-positive patients.

RESULTS

Of this cohort, 7.3% of patients had involvement of the CHALN, and all of them had metastatic spread to first-echelon nodes. Actual median survival of patients with no lymph node involvement was 49 months. In patients with any nodal involvement, the survival was no different when comparing the lymph node positive and negative (13 and 20 months, respectively). Univariate and multivariate analyses likewise attached no significance to the lymph node metastasis, while demonstrating worse survival with positive margin status and poorly differentiated histology. Our DFS analyses yielded similar results.

CONCLUSION

We found no difference in actual survival in node-positive patients regardless of the CHALN involvement and recommended against its assessment in prognosticating survival or guiding surgical treatment.

Short- and long-term outcomes of robotic versus open radical antegrade modular pancreatosplenectomy: a retrospective propensity score-matched cohort study

BACKGROUND

Robotic distal pancreatectomy has increasingly been accepted as it has overcome some of the limitations of open distal pancreatectomy, whilst the outcomes following robotic radical antegrade modular pancreatosplenectomy (RAMPS) in patients with pancreatic ductal adenocarcinoma (PDAC) are still uncertain. This study aimed to evaluate the short and long-term outcomes of robotic RAMPS and open RAMPS for PDAC.

METHODS

The patients who underwent robotic RAMPS and open RAMPS for PDAC at our clinical centre between January 2017 and December 2021 were reviewed. After a propensity score matching (PSM) at a 1:1 ratio, the perioperative and pathological outcomes in the both groups were reviewed. Univariable and multivariable Cox regression analyses were used to identify independent prognosis factors for overall survival (OS) and recurrence-free survival (RFS) of these patients.

RESULTS

318 cases were recorded in robotic and open groups. The robotic group showed advantages in operative time [205.00 (166.00, 240.00) min vs 235 (184.75, 270.00) min, P = 0.002], estimated blood loss [100 (50, 100) ml vs 300 (100, 400) ml, P < 0.001], delayed gastric emptying [0 vs 5.03%, P = 0.007] and postoperative hospital stay [7.00 (5.00, 10.00) days vs 11.00 (8.00, 14.00) days, P < 0.001]. There were no significant differences in rate of severe postoperative complications between the robotic group and the open group. Multivariable analysis showed that carbohydrate antigen 19-9, estimated blood loss, N stage, tumour differentiation, chemotherapy and vascular invasion were independent risk factors for OS and RFS of these patients.

CONCLUSIONS

Robotic RAMPS was safe and had some advantages over open RAMPS for PDAC. There were no significantly differences in oncological outcomes and long-term survival rates between the robotic and open groups. Robotic RAMPS expanded the indications for minimally invasive surgeries for PDAC to a certain extent.

Research Progress of Neural Invasion in Pancreatic Cancer

Pancreatic cancer is one of the highly malignant gastrointestinal tumors in humans, and patients suffer from cancer pain in the process of cancer. Most patients suffer from severe pain in the later stages of the disease. The latest studies have shown that the main cause of pain in patients with pancreatic cancer is neuroinflammation caused by tumor cells invading nerves and triggering neuropathic pain on this basis, which is believed to be the result of nerve invasion. Peripheral nerve invasion (PNI), defined as the presence of cancer cells along the nerve or in the epineurial, perineural, and endoneurial spaces of the nerve sheath, is a special way for cancer to spread to distant sites. However, due to limited clinical materials, the research on the mechanism of pancreatic cancer nerve invasion has not been carried out in depth. In addition, perineural invasion is considered to be one of the underlying causes of recurrence and metastasis after pancreatectomy and an independent predictor of prognosis. This article systematically reviewed the neural invasion of pancreatic cancer through bioinformatics analysis, clinical manifestations and literature reviews.

Surgical Strategies to Dissect around the Superior Mesenteric Artery in Robotic Pancreatoduodenectomy

The concept of the superior mesenteric artery (SMA)-first approach has been widely accepted in pancreatoduodenectomy. However, few studies have reported surgical approaches to the SMA in robotic pancreatoduodenectomy (RPD). Herein, we present our surgical strategies to dissect around the SMA in RPD. Among the various approaches, our standard protocol for RPD included the right approach to the SMA, which can result in complete tumor resection in most cases. In patients with malignant diseases requiring lymphadenectomy around the SMA, we developed a novel approach by combining the left and right approaches in RPD. Using this approach, circumferential dissection around the SMA can be achieved through both the left and right sides. This approach can also be helpful in patients with obesity or intra-abdominal adhesions. The present study summarizes the advantages and disadvantages of both the approaches during RPD. To perform RPD safely, surgeons should understand the different surgical approaches and select the best approach or a combination of different approaches, depending on demographic, anatomical, and oncological factors.