Lymph node size and its association with nodal metastasis in ductal adenocarcinoma of the pancreas

Long-term outcomes of neoadjuvant gemcitabine, nab-paclitaxel, and S1 (GAS) in borderline resectable pancreatic cancer with arterial contact: Results from a phase II trial

BACKGROUND/PURPOSE

This study reports the long-term results of a phase II trial evaluating the clinical efficacy of neoadjuvant gemcitabine, nab-paclitaxel, and S1 (GAS) in borderline resectable pancreatic cancer with arterial contact (BRPC-A).

METHODS

A multicenter, single-arm, phase II trial was conducted. Patients received six cycles of GAS and patients without progressive disease were intended for R0 resection.

RESULTS

Of the 47 patients, 45 (96%) underwent pancreatectomy. At the time of this analysis, all patients were updated with no loss to follow-up. A total of 30 patients died, while the remaining 17 patients were followed for a median of 68.1 months. The updated median overall survival (OS) was 41.0 months, with 2- and 5-year OS rates of 68.0% and 44.6%, respectively. Multivariate analysis in the preoperative model showed that a tumor diameter reduction rate ≥10% and a CA19-9 reduction rate ≥95% after neoadjuvant chemotherapy remained independently associated with favorable survival. In the postoperative multivariate model, no lymph node metastasis, no major surgical complications, and completion of adjuvant chemotherapy were independently associated with improved OS.

CONCLUSIONS

This long-term evaluation of the neoadjuvant GAS trial demonstrated the high efficacy of the regimen, suggesting that it is a promising treatment option for patients with BRPC-A.

Predictive role of radiomics features extracted from preoperative cross-sectional imaging of pancreatic ductal adenocarcinoma in detecting lymph node metastasis: a systemic review and meta-analysis

Lymph node metastases are associated with poor clinical outcomes in pancreatic ductal adenocarcinoma (PDAC). In preoperative imaging, conventional diagnostic modalities do not provide the desired accuracy in diagnosing lymph node metastasis. The current review aims to determine the pooled diagnostic profile of studies examining the role of radiomics features in detecting lymph node metastasis in PDAC. PubMed, Google Scholar, and Embase databases were searched for relevant articles. The quality of the studies was examined using the Radiomics Quality Score and Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tools. Pooled results for sensitivity, specificity, likelihood, and odds ratios with the corresponding 95% confidence intervals (CIs) were calculated using a random-effect model (DerSimonian-Liard method). No significant publication bias was detected among the studies included in this meta-analysis. The pooled sensitivity of the validation datasets included in the study was 77.4% (72.7%, 81.5%) and pooled specificity was 72.4% (63.8, 79.6%). The diagnostic odds ratio of the validation datasets was 9.6 (6.0, 15.2). No statistically significant heterogeneity was detected for sensitivity and odds ratio (P values of 0.3 and 0.08, respectively). However, there was significant heterogeneity concerning specificity (P = 0.003). The pretest probability of having lymph node metastasis in the pooled databases was 52% and a positive post-test probability was 76% after the radiomics features were used, showing a net benefit of 24%. Classifiers trained on radiomics features extracted from preoperative images can improve the sensitivity and specificity of conventional cross-sectional imaging in detecting lymph node metastasis in PDAC.

Prevalence of Adenopathy at Chest Computed Tomography After Vaccination for Severe Acute Respiratory Syndrome Coronavirus 2

OBJECTIVE

This study aimed to determine the prevalence of axillary and subpectoral (SP) lymph nodes after ipsilateral COVID-19 vaccine administration on chest computed tomography (CT).

METHODS

Subjects with chest CTs between 2 and 25 days after a first or second vaccine dose, December 15, 2020, to February 12, 2021, were included. Orthogonal measures of the largest axillary and SP nodes were recorded by 2 readers blinded to vaccine administration and clinical details. A mean nodal diameter discrepancy of ≥6 mm between contralateral stations was considered positive for asymmetry. Correlation with the side of vaccination, using a Spearman rank correlation, was performed on the full cohort and after excluding patients with diseases associated with adenopathy.

RESULTS

Of the 138 subjects (81 women, 57 men; mean [SD] age, 74.4 ± 11.7 years), 48 (35%) had asymmetrically enlarged axillary and/or SP lymph nodes, 42 (30%) had ipsilateral, and 6 (4%) had contralateral to vaccination ( P = 0.003). Exclusion of 29 subjects with conditions associated with adenopathy showed almost identical correlation, with asymmetric nodes in 32 of 109 (29%) ipsilateral and in 5 of 109 (5%) contralateral to vaccination ( P = 0.002).

CONCLUSIONS

Axillary and/or SP lymph nodes ipsilateral to vaccine administration represents a clinical conundrum. Asymmetric nodes were detected at CT in 30% of subjects overall and 29% of subjects without conditions associated with adenopathy, approximately double the prevalence rate reported to the Centers for Disease Control and Prevention by vaccine manufacturers. When interpreting examinations correlation with vaccine administration timing and site is important for pragmatic management.

Effects of the Largest Metastatic Lymph Node Size on the Outcomes of Patients who Underwent Pancreaticoduodenectomy for Pancreatic Ductal Adenocarcinoma

Objectives

Prognostic importance of metastatic lymph nodes in pancreatic cancer is always garnered attention due to dismal prognosis, with some quantitative factors drawing attention for significantly predicting outcomes. Size is one of the easy approach morphological characteristics of the lymph node, and data for effect of largest metastatic lymph node (LMLN) size on survival outcomes are lacking in pancreatic cancer. We aim to evaluate the effect of LMLN size on the prognosis of patients with pancreatic ductal adenocarcinoma (PDAC).

Methods

This retrospective study evaluates the effect of LMLN size on survival outcomes by grouping the patients who were surgically treated for PDAC, according to their lymph node stage and calculated cutoff value for LMLN size, between February 2015 and May 2020.

Results

In the study cohort of 131 patients, the mean age was 63.9±10.8 years and 77 patients were female. Ninety-nine of the patients had pN1, 32 had pN2 stage disease. The optimal cutoff point of LMLN size for predicting the prognosis was calculated as 7.5 mm (sensitivity = 81% and specificity = 81%). 34 (34.3%) of pN1 and 7 (21.9%) of pN2-staged patients had lymph node smaller than 7.5 mm. Three-year survival was significantly longer for patients whose LMLN size was <7.5 mm (56.2-18.2%, p<0.001). Whereas, the patients with LMLN size <7.5 mm had statistically significant longer median survival rate in the subgroup of patients with pN1 lymph node stage, no significant difference in median survival rates was observed between subgroups of pN2 patients (p=0.237).

Conclusion

The present study demonstrated that the LMLN size was one of the potential predictors of survival in patients with PDAC.

Comparison of MRI and CT-based radiomics for preoperative prediction of lymph node metastasis in pancreatic ductal adenocarcinoma

Background

The preoperative prediction of lymph node metastasis (LNM) in pancreatic ductal adenocarcinoma (PDAC) is essential in prognosis and treatment strategy formulation.

Purpose

To compare the performance of computed tomography (CT) and magnetic resonance imaging (MRI) radiomics models for the preoperative prediction of LNM in PDAC.

Material and Methods

In total, 160 consecutive patients with PDAC were retrospectively included, who were divided into the training and validation sets (ratio of 8:2). Two radiologists evaluated LNM basing on morphological abnormalities. Radiomics features were extracted from T2-weighted imaging, T1-weighted imaging, and multiphase contrast enhanced MRI and multiphase CT, respectively. Overall, 1184 radiomics features were extracted from each volume of interest drawn. Only features with an intraclass correlation coefficient ≥0.75 were included. Three sequential feature selection steps—variance threshold, variance thresholding and least absolute shrinkage selection operator—were repeated 20 times with fivefold cross-validation in the training set. Two radiomics models based on multiphase CT and multiparametric MRI were built with the five most frequent features. Model performance was evaluated using the area under the curve (AUC) values.

Results

Multiparametric MRI radiomics model achieved improved AUCs (0.791 and 0.786 in the training and validation sets, respectively) than that of the CT radiomics model (0.672 and 0.655 in the training and validation sets, respectively) and of the radiologists’ assessment (0.600–0.613 and 0.560–0.587 in the training and validation sets, respectively).

Conclusion

Multiparametric MRI radiomics model may serve as a potential tool for preoperatively evaluating LNM in PDAC and had superior predictive performance to multiphase CT-based model and radiologists’ assessment.

Regional lymph node metastasis detected on preoperative CT and/or FDG-PET may predict early recurrence of pancreatic adenocarcinoma after curative resection

The objective of this study was to evaluate the role of regional lymph node (LN) metastasis detected on preoperative CT and/or ¹⁸F-fluoro-2-deoxyglucose-positron emission tomography (FDG-PET) scans in the prediction of early tumor recurrence after curative surgical resection of pancreatic ductal adenocarcinoma (PDAC). This retrospective study included 137 patients who underwent upfront surgery with R0 resection of PDAC between 2013 and 2016. Regional LN metastasis was identified using two criteria: positive findings for regional LN metastasis on either preoperative CT or FDG-PET scans (LN_OR), or on both preoperative CT and FDG-PET scans (LN_AND). A total of 55 patients had early tumor recurrence within 12 months after curative resection. Univariable and multivariable Cox proportional hazard regression analysis showed that preoperative carbohydrate antigen 19-9 (CA19-9) levels, preoperative locally advanced status, and regional LN metastasis (both LN_OR and LN_AND criteria) were significant risk factors for early recurrence. Positive LN_OR and LN_AND showed significantly poorer recurrence-free survival compared to negative regional LN metastasis groups (p = 0.048 and p = 0.020, respectively). Compared with the LN_AND criteria, the LN_OR criteria provided higher sensitivity (22.4% vs. 15.5%, p = 0.046) and a higher negative predictive value (61.9% vs. 59.8%, p = 0.046). The LN_OR definition provided more sensitive and accurate performance in diagnosing preoperative regional LN metastasis.

Evaluation of the 8th Edition AJCC Staging System for the Clinical Staging of Pancreatic Cancer

The 8th edition of the American Joint Committee on Cancer (AJCC) staging system for pancreatic cancer (PC) has been validated for pathological staging; however, its significance for clinical staging remains uncertain. We validated the prognostic performance and suitability of the current staging system for the clinical staging of PC. We identified 1043 patients from our PC registry who were staged by imaging according to the 8th edition staging system and conducted analysis, including overall survival (OS) comparison. Gradual prognostic stratification according to stage hierarchy yielded significant OS differences between stage groups, except between stage I and II (p = 0.193). A substage comparison revealed no survival differences between IB (T2N0) and IIA (T3N0), which were divided by the T3 criterion only (p = 0.278). A higher N stage had significantly shorter OS than a lower N stage (all pairwise p < 0.05). However, among the 150 patients who received upfront surgery, the pathological stage was more advanced than the clinical stage in 86 (57.3%), mostly due to a false-negative cN0 (70.9%). Our results suggest that the new definition of T3 and the number-based N criteria in the 8th edition AJCC staging system may be not adequate for clinical staging. Establishing separate criteria more suitable for clinical staging should be considered.

Role of CA 19.9 in the Management of Resectable Pancreatic Cancer: State of the Art and Future Perspectives

Background: Surgery still represents the gold standard of treatment for resectable pancreatic ductal adenocarcinoma (PDAC). Neoadjuvant treatments (NAT), currently proposed for borderline and locally advanced PDACs, are gaining momentum even in resectable tumors due to the recent interesting concept of “biological resectability”. In this scenario, CA 19.9 is having increasing importance in preoperative staging and in the choice of therapeutic strategies. We aimed to assess the state of the art and to highlight the future perspectives of CA 19.9 use in the management of patients with resectable pancreatic cancer. Methods: A PubMed database search of articles published up to December 2021 has been carried out. Results: Elevated pre-operative levels of CA 19.9 have been associated with reduced overall survival, nodal involvement, and margin status positivity after surgery. These abilities of CA 19.9 increase when combined with radiological or different biological criteria. Unfortunately, due to strong limitations of previously published articles, CA 19.9 alone cannot be yet considered as a key player in resectable pancreatic cancer patient management. Conclusion: The potential of CA 19.9 must be fully explored in order to standardize its role in the “biological staging” of patients with resectable pancreatic cancer.

Does direct invasion of peripancreatic lymph nodes impact survival in patients with pancreatic ductal adenocarcinoma? A retrospective dual-center study

BACKGROUND

Pancreatic ductal adenocarcinoma can directly invade the peripancreatic lymph nodes; however, the significance of direct lymph node invasion is controversial, and it is currently classified as lymph node metastasis. This study aimed to identify the impact of direct invasion of peripancreatic lymph nodes on survival in patients with pancreatic ductal adenocarcinoma.

METHODS

A total of 411 patients with resectable/borderline resectable pancreatic ductal adenocarcinoma who underwent pancreatic resection at two high-volume centers from 2006 to 2016 were evaluated retrospectively.

RESULTS

Sixty (14.6%) patients had direct invasion of the peripancreatic lymph nodes without isolated lymph node metastasis (N-direct group), 189 (46.0%) had isolated lymph node metastasis (N-met group), and 162 (39.4%) had neither direct invasion nor isolated metastasis (N0 group). There was no significant difference in median overall survival between the N-direct group (35.0 months) and the N0 group (45.6 month) (p = 0.409), but survival was significantly longer in the N-direct compared with the N-met group (25.0 months) (p = 0.003). Similarly, median disease-free survival was similar in the N-direct (21.0 months) and N0 groups (22.7 months) (p = 0.151), but was significantly longer in the N-direct compared with the N-met group (14.0 months) (p < 0.001). Multivariate analysis identified resectability, adjuvant chemotherapy, and isolated lymph node metastasis as independent predictors of overall survival. However, direct lymph node invasion was not a predictor of survival.

CONCLUSION

Direct invasion of the peripancreatic lymph nodes had no effect on survival in patients undergoing pancreatic resection for pancreatic ductal adenocarcinoma, and should therefore not be classified as lymph node metastasis.

CA19.9 Serum Level Predicts Lymph-Nodes Status in Resectable Pancreatic Ductal Adenocarcinoma: A Retrospective Single-Center Analysis

Background

The choice between upfront surgery or neoadjuvant treatments (NAT) for resectable pancreatic ductal adenocarcinoma (R-PDAC) is controversial. R-PDAC with potential nodal involvement could benefit from NT. Ca (Carbohydrate antigen) 19.9 and serum albumin levels, alone or in combination, have proven their efficacy in assessing PDAC prognosis. The objective of this study was to evaluate the role of Ca 19.9 serum levels in predicting nodal status in R-PDAC.

Methods

Preoperative Ca 19.9, as well as serum albumin levels, of 165 patients selected for upfront surgery have been retrospectively collected and correlated to pathological nodal status (N), resection margins status (R) and vascular resections (VR). We further performed ROC curve analysis to identify optimal Ca 19.9 cut-off for pN+, R+ and vascular resection prediction.

Results

Increased Ca 19.9 levels in 114 PDAC patients were significantly associated with pN+ (p <0.001). This ability, confirmed in all the series by ROC curve analysis (Ca 19.9 ≥32 U/ml), was lost in the presence of hypoalbuminemia. Furthermore, Ca 19.9 at the cut off >418 U/ml was significantly associated with R+ (87% specificity, 36% sensitivity, p 0.014). Ca 19.9, at the cut-off >78 U/ml, indicated a significant trend to predict the need for VR (sensitivity 67%, specificity 53%; p = 0.059).

Conclusions

In R-PDAC with normal serum albumin levels, Ca 19.9 predicts pN+ and R+, thus suggesting a crucial role in deciding on NAT.

Identification of key genes in lung adenocarcinoma based on a competing endogenous RNA network

Lung adenocarcinoma (LUAD) is the most commonly diagnosed type of lung cancer and exhibits a high morbidity. The present study aimed to investigate the long non-coding RNA (lncRNA)-associated competing endogenous RNA (ceRNA) mechanisms in LUAD. The receptor activity modifying protein 2-antisense RNA 1 (RAMP2-AS1) was identified using GSE113852 and GSE130779 datasets downloaded from the Gene Expression Omnibus database, and the downregulation of RAMP2-AS1 was the most significant in LUAD. In addition, microRNA (miR)-296-5p was identified to bind to RAMP2-AS1 via bioinformatics analysis. Subsequently, CD44, cyclin D3 (CCND3), neurocalcin δ (NCALD), microtubule actin crosslinking factor 1 (MACF1) and potassium channel tetramerization domain containing 15 were obtained by intersecting the predicted target genes of miR-296-5p and 368 differentially expressed mRNAs in LUAD. According to the Gene Expression Profiling Interactive Analysis and UALCAN databases, these five mRNAs were downregulated in LUAD, and their expression levels were positively correlated with those of RAMP2-AS1. CD44, CCND3, NCALD and MACF1 were selected as key mRNAs in LUAD based on prognostic analyses. Furthermore, functional enrichment analyses were performed and an interaction network was constructed to reveal the functions of the RAMP2-AS1-associated ceRNA in LUAD. The results indicated that the functions were mainly enriched in generic transcription pathways, cyclin D-associated events in G₁ and epithelial stromal transformation. Reverse transcription-quantitative PCR assays revealed that RAMP2-AS1, CD44, CCND3, NCALD and MACF1 expression was lower in tumor tissues than in normal tissues, while miR-296-5p expression was higher in tumor tissues compared with in normal tissues. The association between RAMP2-AS1 and MACF1 was further confirmed using in vitro experiments. Overall, the present results indicated that RAMP2-AS1, miR-296-5p, CD44, CCND3, NCALD and MACF1 may be involved in LUAD progression and may therefore serve as potential biomarkers and provide a theoretical basis for the study of the pathogenesis of LUAD.