A Preoperative Prognostic Scoring System to Predict Prognosis for Resectable Pancreatic Cancer: Who Will Benefit from Upfront Surgery?

Loss of chromosome 9p21 is associated with a poor prognosis in adenosquamous carcinoma of the pancreas

Adenosquamous carcinoma of the pancreas (ASCP) is a rare histological subtype of pancreatic cancer with a poor prognosis and a high metastasis rate. However, little is known about its genomic landscape and prognostic biomarkers. A total of 48 ASCP specimens and 98 pancreatic ductal adenocarcinoma (PDAC) tumour specimens were sequenced to explore the genomic landscape and prognostic biomarkers. The homozygous deletion of the 9p21.3 region (including CDKN2A, CDKN2B, and MTAP) (9p21 loss) occurred in both ASCP and PDAC, and a higher frequency of 9p21 loss was observed in ASCP (12.5% vs 2.0%, P = 0.022). Notably, 9p21 loss was significantly associated with poor disease-free survival (DFS) in ASCP patients (mDFS (Median DFS) = 4.17 vs 7.33 months, HR (Hazard Ratio) = 3.70, P = 0.009). The most common gene alterations in patients with ASCP were KRAS (96%), TP53 (81%), CDKN2A (42%), SMAD4 (21%), CDKN2B (13%), and FAT3 (13%). The mutation rates of ACVR2A (6.25% vs 0%), FANCA (6.25% vs 0%), RBM10 (6.25% vs 0%), and SPTA1 (8.33% vs 1.02%) were significantly higher in ASCP than in PDAC. In conclusion, we have comprehensively described the genomic landscape of the largest cohort of ASCP patients to date and highlight that 9p21 loss may be a promising prognostic biomarker for ASCP, which provides a molecular basis for prognosis prediction and new therapeutic strategies for ASCP.

Superior mesenteric vein/portal vein contact in preoperative imaging indicates biological malignancy in anatomically resectable pancreatic cancer

BACKGROUND

Pancreatic cancer in contact with the superior mesenteric vein/portal vein is classified as resectable pancreatic cancer; however, the biological malignancy and treatment strategy have not been clarified.

METHODS

Data from 186 patients who underwent pancreatectomy for pancreatic cancer were evaluated using a prospectively maintained database. The patients were classified as having resectable tumors without superior mesenteric vein/portal vein contact and with superior mesenteric vein/portal vein contact of ≤180°. Disease-free survival, overall survival, and prognostic factors were analyzed.

RESULTS

In the univariate analysis, superior mesenteric vein/portal vein contact in resectable pancreatic cancer was a significant prognostic index for disease-free survival and overall survival. In the multivariate analysis for poor disease-free survival, the superior mesenteric vein/portal vein contact remained significant (hazard ratio = 2.13, 95% confidence interval: 1.29-3.51; p < 0.01). In the multivariate analysis, superior mesenteric vein/portal vein contact was a significant independent prognostic index for overall survival (hazard ratio = 2.17, 95% confidence interval: 1.27-3.70; p < 0.01), along with sex, tumor differentiation, nodal involvement, and adjuvant chemotherapy. Portal vein resection for superior mesenteric vein/portal vein contact did not improve the overall survival (p = 0.86).

CONCLUSIONS

Superior mesenteric vein/portal vein contact in resectable pancreatic cancer was found to be an independent predictor of disease-free survival and overall survival after elective resection. Thus, pancreatic cancer in contact with the superior mesenteric vein/portal vein may be considered as borderline resectable pancreatic cancer.

Limited impact of discretization/interpolation parameters on the predictive power of CT radiomic features in a surgical cohort of pancreatic cancer patients

PURPOSE

To explore the variation of the discriminative power of CT (Computed Tomography) radiomic features (RF) against image discretization/interpolation in predicting early distant relapses (EDR) after upfront surgery.

MATERIALS AND METHODS

Data of 144 patients with pre-surgical high contrast CT were processed consistently with IBSI (Image Biomarker Standardization Initiative) guidelines. Image interpolation/discretization parameters were intentionally changed, including cubic voxel size (0.21-27 mm³) and binning (32-128 grey levels) in a 15 parameter's sets. After excluding RF with poor inter-observer delineation agreement (ICC < 0.80) and not negligible inter-scanner variability, the variation of 80 RF against discretization/interpolation was first quantified. Then, their ability in classifying patients with early distant relapses (EDR, < 10 months, previously assessed at the first quartile value of time-to-relapse) was investigated in terms of AUC (Area Under Curve) variation for those RF significantly associated to EDR.

RESULTS

Despite RF variability against discretization/interpolation parameters was large and only 30/80 RF showed %COV < 20 (%COV = 100*STDEV/MEAN), AUC changes were relatively limited: for 30 RF significantly associated with EDR (AUC values around 0.60-0.70), the mean values of SD of AUC variability and AUC range were 0.02 and 0.05 respectively. AUC ranges were between 0.00 and 0.11, with values ≤ 0.05 in 16/30 RF. These variations were further reduced when excluding the extreme values of 32 and 128 for grey levels (Average AUC range 0.04, with values between 0.00 and 0.08).

CONCLUSIONS

The discriminative power of CT RF in the prediction of EDR after upfront surgery for pancreatic cancer is relatively invariant against image interpolation/discretization within a large range of voxel sizes and binning.

Predictive factors for early recurrence after pancreaticoduodenectomy in patients with resectable pancreatic head cancer: A multicenter retrospective study

BACKGROUND

Patients diagnosed with resectable pancreatic ductal adenocarcinoma often experience early recurrence even after upfront R0 resection. This study aimed to define early recurrence and identify preoperative risk factors for early recurrence after upfront pancreaticoduodenectomy in patients with resectable pancreatic ductal adenocarcinoma of the pancreatic head.

METHODS

This multicenter, retrospective study involved 500 patients who underwent pancreaticoduodenectomy resectable pancreatic ductal adenocarcinoma of the pancreatic head at 10 institutions between 2007 and 2016. Preoperative, intraoperative, and postoperative clinicopathological results were compared between early and non-early recurrence groups. Predictors of early recurrence were determined using statistical analyses.

RESULTS

Log-rank tests revealed a significant difference (P < .001) between recurrence within 3 to 6 months and 6 to 9 months. Early recurrence was subsequently defined as recurrence within 6 months. Patients were categorized into early recurrence (n = 104) and non-early recurrence groups (n = 389). The median overall survival of the early and non-early recurrence groups was 8.6 months and 42.6 months (P < .001), respectively. Preoperatively, high carbohydrate antigen 19-9 levels ≥120 U/mL, retroperitoneal invasion, and diabetes mellitus were identified as independent predictive risk factors for early recurrence according to multivariate analysis. Comparing survival rates among patients with 3, 2, 1, or none of these factors, the median overall survival was 17.6 (n = 90), 21.2 (n = 184), 47 (n = 141), and 61.5 (n = 73) months, respectively.

CONCLUSION

The optimal period that defines the early recurrence for resectable pancreatic ductal adenocarcinoma of the pancreatic head is 6 months. Tumor size ≥20 mm, preoperative carbohydrate antigen 19-9 levels ≥120 U/mL, retroperitoneal invasion of the tumor, and the presence of diabetes mellitus are independently associated with early recurrence.

Heterogeneity of metabolic adaptive capacity affects the prognosis among pancreatic ductal adenocarcinomas

BACKGROUND

Evolutionary cancer has a supply mechanism to satisfy higher energy demands even in poor-nutrient conditions. Metabolic reprogramming is essential to supply sufficient energy. The relationship between metabolic reprogramming and the clinical course of pancreatic ductal adenocarcinoma (PDAC) remains unclear. We aimed to clarify the differences in metabolic status among PDAC patients.

METHODS

We collected clinical data from 128 cases of resectable PDAC patients undergoing surgery. Sixty-three resected tissues, 15 tissues from the low carbohydrate antigen 19-9 (CA19-9), 38-100 U/mL, and high CA19-9, > 500 U/mL groups, and 33 non-tumor control parts, were subjected to tandem mass spectrometry workflow to systematically explore metabolic status. Clinical and proteomic data were compared on the most used PDAC biomarker, preoperative CA19-9 value.

RESULTS

Higher CA19-9 levels were clearly associated with higher early recurrence (p < 0.001), decreased RFS (p < 0.001), and decreased DSS (p = 0.025). From proteomic analysis, we discovered that cancer evolution-related as well as various metabolism-related pathways were more notable in the high group. Using resected tissue immunohistochemical staining, we learned that high CA19-9 PDAC demonstrated aerobic glycolysis enhancement, yet no decrease in protein synthesis. We found a heterogeneity of various metabolic processes, including carbohydrates, proteins, amino acids, lipids, and nucleic acids, between the low and the high groups, suggesting differences in metabolic adaptive capacity.

CONCLUSIONS

Our study found metabolic adaptation differences among PDAC cases, pertaining to both cancer evolution and the prognosis. CA19-9 can help estimate the metabolic adaptive capacity of energy supply for PDAC evolution.

Predictors of Long-Term Survival in Pancreatic Ductal Adenocarcinoma after Pancreatectomy: TP53 and SMAD4 Mutation Scoring in Combination with CA19-9

BACKGROUND

Pancreatic ductal adenocarcinoma (PDA) is a fatal cancer for which even unfavorable clinicopathological factors occasionally fail to preclude long-term survival. We sought to establish a scoring system that utilizes measurable pre-intervention factors for predicting survival following surgical resection.

METHODS

We retrospectively analyzed 34 patients who died from short-term recurrences and 32 long-term survivors among 310 consecutively resected patients with PDA. A logistic regression model was used to define factors related to clinical parameters, molecular profiles of 18 pancreatic cancer-associated genes, and aberrant expression of major tumor suppressors.

RESULTS

Carbohydrate antigen 19-9 (CA19-9) had the best ability to classify patients with short-term recurrence and long-term survivors [odds ratio 21.04, 95% confidence interval (CI) 4.612-96.019], followed by SMAD4 and TP53 mutation scoring (odds ratio 41.322, 95% CI 3.156-541.035). Missense TP53 mutations were strongly associated with the nuclear expression of p53, whereas truncating mutations were associated with the absence of nuclear p53. The former subset was associated with a worse prognosis. The combination of aberrant SMAD4 and mutation types of TP53 exhibited a better resolution for distinguishing patients with short-term recurrences from long-term survivors (compared with the assessment of the number of mutated KRAS, CDKN2A, TP53, and SMAD4 genes). Calibration of mutation scores combined with CA19-9 in a logistic regression model setting demonstrated a practical effect in classifying long survivors and patients with early recurrence (c-statistic = 0.876).

CONCLUSIONS

Genetic information, i.e., TP53 mutation types and SMAD4 abnormalities, combined with CA19-9, will be a valuable tool for improving surgical strategies for pancreatic cancer.

Development of a Biomarker-Based Scoring System Predicting Early Recurrence of Resectable Pancreatic Duct Adenocarcinoma

Background

Resectable pancreatic ductal adenocarcinoma (R-PDAC) often recurs early after radical resection, which is associated with poor prognosis. Predicting early recurrence preoperatively is useful for determining the optimal treatment.

Patients and methods

One hundred and seventy-eight patients diagnosed with R-PDAC on computed tomography (CT) imaging and undergoing radical resection at Hirosaki University Hospital from 2005 to 2019 were retrospectively analyzed. Patients with recurrence within 6 months after resection formed the early recurrence (ER) group, while other patients constituted the non-early recurrence (non-ER) group. Early recurrence prediction score (ERP score) was developed using preoperative parameters.

Results

ER was observed in 45 patients (25.3%). The ER group had significantly higher preoperative CA19-9 (p = 0.03), serum SPan-1 (p = 0.006), and CT tumor diameter (p = 0.01) compared with the non-ER group. The receiver operating characteristic (ROC) curve analysis identified cutoff values for CA19-9 (133 U/mL), SPan-1 (78.2 U/mL), and preoperative tumor diameter (23 mm). When the parameter exceeded the cutoff level, 1 point was given, and the total score of the three factors was defined as the ERP score. The group with an ERP score of 3 had postoperative recurrence-free survival (RFS) of 5.5 months (95% CI 3.02–7.98). Multivariate analysis for ER-related perioperative and surgical factors identified ERP score of 3 [odds ratio (OR) 4.63 (95% CI 1.82–11.78), p = 0.0013] and R1 resection [OR 3.20 (95% CI 1.01–10.17), p = 0.049] as independent predictors of ER.

Conclusions

For R-PDAC, ER could be predicted by the scoring system using preoperative serum CA19-9 and SPan-1 levels and CT tumor diameter, which may have great significance in identifying patients with poor prognoses and avoiding unnecessary surgery.

Prediction of Early Distant Recurrence in Upfront Resectable Pancreatic Adenocarcinoma: A Multidisciplinary, Machine Learning-Based Approach

Simple Summary

If pancreatic adenocarcinoma is assessed to be technically resectable, curative surgery is still suggested as the primary treatment option; however, the recurrence rate can be very high even in this selected population. The aim of our retrospective study was to develop a preoperative model to accurately stratify upfront resectable patients according to the risk of early distant disease relapse after surgery (<12 months from index procedure). Through a machine learning-based approach, we identified one biochemical marker (serum level of CA19.9), one radiological finding (necrosis) and one radiomic feature (SurfAreaToVolumeRatio), all significantly associated with the early resurge of distant recurrence. A model composed of these three variables only allowed identification of those patients at high risk for early distant disease relapse (50% chance of developing metastases within 12 months after surgery), who would benefit from neoadjuvant chemotherapy instead of upfront surgery.

Abstract

Despite careful selection, the recurrence rate after upfront surgery for pancreatic adenocarcinoma can be very high. We aimed to construct and validate a model for the prediction of early distant recurrence (<12 months from index surgery) after upfront pancreaticoduodenectomy. After exclusions, 147 patients were retrospectively enrolled. Preoperative clinical and radiological (CT-based) data were systematically evaluated; moreover, 182 radiomics features (RFs) were extracted. Most significant RFs were selected using minimum redundancy, robustness against delineation uncertainty and an original machine learning bootstrap-based method. Patients were split into training (n = 94) and validation cohort (n = 53). Multivariable Cox regression analysis was first applied on the training cohort; the resulting prognostic index was then tested in the validation cohort. Clinical (serum level of CA19.9), radiological (necrosis), and radiomic (SurfAreaToVolumeRatio) features were significantly associated with the early resurge of distant recurrence. The model combining these three variables performed well in the training cohort (p = 0.0015, HR = 3.58, 95%CI = 1.98–6.71) and was then confirmed in the validation cohort (p = 0.0178, HR = 5.06, 95%CI = 1.75–14.58). The comparison of survival curves between low and high-risk patients showed a p-value <0.0001. Our model may help to better define resectability status, thus providing an actual aid for pancreatic adenocarcinoma patients’ management (upfront surgery vs. neoadjuvant chemotherapy). Independent validations are warranted.

Prognostic significance of skeletal muscle decrease in unresectable pancreatic cancer: Survival analysis using the Weibull exponential distribution model

BACKGROUND/OBJECTIVES

Decrease in skeletal muscle mass and function is associated with a poor prognosis following surgical resection of pancreatic ductal adenocarcinomas (PDAs). This study evaluated whether skeletal muscle mass decrease affects PDA outcomes.

METHODS

Data of 112 patients with advanced and unresectable PDA who underwent chemotherapy in a single institution were retrospectively analyzed. Information on age, sex, hematological investigations, including systemic inflammation-based markers and nutritional assessment biomarkers, and imaging parameters of skeletal muscle mass and visceral adipose tissue were retrieved from the patients' medical records. The efficiency of the Cox, Weibull, and standardized exponential models were compared using hazard ratios and the Akaike Information Criterion (AIC).

RESULTS

Results from the Weibull, Cox, and standardized exponential model analyses indicated that low skeletal muscle mass, Eastern Cooperative Oncology Group performance status (PS), and the requirement of biliary drainage were associated with the highest risk of death, followed by carcinoembryonic antigen (CEA) levels and the presence of ascites. The AIC value from the four significant parameters was lowest for the Weibull-exponential distribution (222.3) than that of the Cox (653.7) and standardized exponential models (265.7). We developed a model for estimating the 1-year survival probability using the Weibull-exponential distribution.

CONCLUSIONS

Low-skeletal muscle index, PS, requirement of biliary drainage, CEA levels, and presence of ascites are independent factors for predicting poor patient survival after chemotherapy. Improved survival modeling using a parametric approach may accurately predict the outcome of patients with advanced-stage PDA.

The Biological Function Delineated Across Pan-Cancer Levels Through lncRNA-Based Prognostic Risk Assessment Factors for Pancreatic Cancer

Long non-coding RNAs (lncRNAs) play key roles in tumors and function not only as important molecular markers for cancer prognosis, but also as molecular characteristics at the pan-cancer level. Because of the poor prognosis of pancreatic cancer, accurate assessment of prognosis is a key issue in the development of treatment plans for pancreatic cancer. Here we analyzed pancreatic cancer data from The Cancer Genome Atlas and The Genotype Tissue Expression database using Cox regression and lasso regression in analyses using a combination of the two databases as well as only The Cancer Genome Atlas database (Cancer Genome Atlas Research Network et al., 2013). A prognostic risk score model with significant correlation with pancreatic cancer survival was constructed, and two lncRNAs were investigated. Additional analysis of 33 cancers using the two lncRNAs showed that lncRNA TsPOAP1-AS1 was a prognostic marker of seven cancers, among which pancreatic cancer was the most significant, and lncRNA mi600hg was a prognostic marker of ovarian cancer and pancreatic cancer. LncRNA TsPOAP1-AS1 is associated with clinical stage and tumor mutation burden of some cancers as well as a strong degree of immune infiltration in many cancers, while a strong correlation between lncRNA mi600hg and microsatellite instability was observed in several cancers. The results of this study help further our understanding of the different functions of lncRNAs in cancer and may aid in the clinical application of lncRNAs as prognostic factors for cancer.

Surgical Treatment of Pancreatic Ductal Adenocarcinoma

Simple Summary

Surgery is the only potential cure for pancreatic ductal adenocarcinoma and should always be combined with adjuvant chemotherapy or other multimodal treatment. Besides the advances in such multimodal approaches, there has been substantial progress in surgical techniques to especially address advanced resections. These techniques include specific operative steps, such as ‘artery first’ or ‘uncinate first’ approaches as well as techniques that allow safe vascular resection and reconstruction to achieve radical tumor removal. Most recently, also minimally-invasive and robotic approaches have been adopted for pancreatic cancer surgery; however, there is no high-level evidence on these evolving techniques especially with regards to long-term results compared to conventional surgical techniques.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) represents an aggressive tumor of the digestive system with still low five-year survival of less than 10%. Although there are improvements for multimodal therapy of PDAC, surgery still remains the effective way to treat the disease. Combined with adjuvant and/or neoadjuvant treatment, pancreatic surgery is able to enhance the five-year survival up to around 20%. However, pancreatic resection is always associated with a high risk of complications and regarded as one of the most complex fields in abdominal surgery. This review gives a summary on the surgical treatment for PDAC based on the current literature with a special focus on resection techniques.

Surgical Treatment of Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) represents an aggressive tumor of the digestive system with still low five-year survival of less than 10%. Although there are improvements for multimodal therapy of PDAC, surgery still remains the effective way to treat the disease. Combined with adjuvant and/or neoadjuvant treatment, pancreatic surgery is able to enhance the five-year survival up to around 20%. However, pancreatic resection is always associated with a high risk of complications and regarded as one of the most complex fields in abdominal surgery. This review gives a summary on the surgical treatment for PDAC based on the current literature with a special focus on resection techniques.

Essential updates 2019/2020: Multimodal treatment of localized pancreatic adenocarcinoma: Current topics and updates in survival outcomes and prognostic factors

Overall survival of patients with localized pancreatic ductal adenocarcinoma (PDAC) is extremely poor. Therefore, the establishment of multimodal treatment strategies is indispensable for PDAC patients because surgical treatment alone could not contribute to the improvement of survival. In this review article, we focus on the current topics and advancement of the treatments for localized PDAC including resectable, borderline resectable, and locally advanced PDAC in accordance with the articles mainly published from 2019 to 2020. Reviewing the articles, the recent progress of multimodal treatments notably improves the prognosis of patients with localized PDAC. For resectable PDAC, neoadjuvant chemo or chemoradiation therapy, rather than upfront surgery, plays a key role, especially in patients with a large tumor, poor performance status, high tumor marker levels, peripancreatic lymph nodes metastasis, or neural invasion suspected on preoperative imaging. For borderline resectable PDAC, neoadjuvant treatments followed by surgery is a desirable approach, and maintenance of immunonutritional status during the treatments are also important. For locally advanced disease, conversion surgery has a central role in improving a survival outcome; however, its indication should be standardized.

Identification of Preoperative Risk Factors for Poor Survival in Patients with Resectable Pancreatic Cancer Treated with Upfront Surgery

INTRODUCTION

The aim of this study was to identify preoperative risk factors for poor survival in patients with resectable pancreatic ductal adenocarcinoma (PDAC) treated with upfront surgery.

METHODS

Medical records of 268 patients with resectable PDAC defined by resectability status who underwent upfront surgery were reviewed retrospectively. Multivariate analyses were performed to identify preoperative risk factors for recurrence-free survival (RFS) and overall survival (OS). Moreover, a binary logistic regression model was built to determine preoperative independent risk factors of 2- and 3-year recurrence and survival.

RESULTS

Multivariate analyses identified CA19-9 (≥100 U/mL, p < 0.001) as an independent risk factor for poor RFS, and worse performance status (1 or 2, p = 0.03), platelet:lymphocyte ratio (<150, p = 0.04), and preoperative CA19-9 (≥100 U/mL, p < 0.001) as independent risk factors for poor OS. Moreover, preoperative CA19-9 (≥100 U/mL) was the only independent risk factor identified for 2- and 3-year recurrence and survival.

DISCUSSION/CONCLUSION

Preoperative CA19-9 (≥100 U/mL) was the most reliable preoperative predictive factor for poor survival in resectable PDAC treated with upfront surgery. These findings warrant further clinical trials investigating efficacy of neoadjuvant therapy targeting the subset of patients with resectable PDAC who have elevated preoperative CA19-9, namely, those with high risk of poor prognosis.

Essential updates 2018/2019: Current topics in the surgical treatment of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is highly malignant. While cancers in other organs have shown clear improvements in 5-year survival, the 5-year survival rate of pancreatic cancer is approximately 10%. Early relapse and metastasis are not uncommon, making it difficult to achieve an acceptable prognosis even after complete surgical resection of the pancreas. Studies have been performed on various treatments to improve the prognosis of PDAC, and multidisciplinary approaches including non-surgical treatments have led to gradual improvement. In the present literature review, we have described the significance of anatomical and biological resectability criteria, the concept of R0 resection in surgical treatment, the feasibility of minimally invasive surgery, the remarkable development of perioperative chemotherapy, the effectiveness of conversion surgery for unresectable PDAC, and ongoing challenges in PDAC treatment. We also provide an essential update on these subjects by focusing on recent trends and topics.

Clinical implications of the serum CA19-9 level in "biological borderline resectability" and "biological downstaging" in the setting of preoperative chemoradiation therapy for pancreatic cancer

BACKGROUND

Biological factors are emphasized in borderline resectable pancreatic cancer (BRPC), and CA19-9 is an important factor for biological borderline resectability (b-BR). The aim of this study was to investigate the cut-off value of CA19-9 for biological borderline resectability and "biological downstaging" in chemoradiation therapy (CRT) for pancreatic cancer (PC).

METHODS

A total of 407 patients with anatomically resectable PC (a-R) and BRPC (a-BR) received preoperative gemcitabine-based CRT. The b-BR was determined, according to the CA19-9 value prior to preoperative CRT (pre-CA19-9), as the subgroup of a-R cases in which the survival was comparable with that in a-BR cases. "Biological downstaging" was determined based on prognostic analyses regarding the CA19-9 value after preoperative CRT (post-CA19-9) in association with the survival of R cases (a-R cases without the b-BR factor).

RESULTS

The 5-year survival of a-R patients with pre-CA19-9 > 120 U/mL was comparable with that of a-BR patients (44% vs 34%, p = 0.082). The survival of b-BR patients with post-CRT CA19-9 ≤ 37 U/mL (normalized) was comparably favorable with that of R patients (56% vs 65%, p = 0.369). The incidence of distant recurrence was higher in b-BR patients without post-CA19-9 normalization than in those with post-CA19-9 normalization (70% vs 50%, p = 0.003), while the incidence of local recurrence was comparable between these two groups (12% vs 13%, p = 0.986).

CONCLUSIONS

Biological BRPC was determined to be an anatomically resectable disease with pre-CA19-9 > 120 U/mL, and post-CA19-9 normalization indicated "biological downstaging" in b-BR in the preoperative CRT strategy.

Reticular pattern around superior mesenteric artery in computed tomography imaging predicting poor prognosis of pancreatic head cancer

BACKGROUND

Some patients with pancreatic ductal adenocarcinoma (PDAC) demonstrate a reticular pattern around the superior mesenteric artery (SMA) in computed tomography scans. This study aimed to clarify the clinical significance of the reticular pattern in pancreatic head cancer.

METHODS

A total of 91 patients with pancreatic head cancer, who underwent upfront pancreaticoduodenectomy between 2004 and 2017, were included. Patients without reticular pattern (Non-group, n = 39); with reticular pattern around SMA (Ret-group, n = 39); and with soft tissue contact (Soft-group, n = 13) were compared.

RESULTS

Median overall survival (OS) of patients in the Ret-group was significantly worse than that in the Non-group (21.3 vs. 57.0 months; P < 0.001) and equivalent to that in the Soft-group. In the multivariate analysis, reticular pattern and high CA19-9 levels were identified as independent predictors of OS. Microscopically, only fibrotic thickenings were identified corresponding to the reticular pattern areas, and no difference in the frequency of early local recurrence was noted between the Non and Ret-groups. Lymphovascular invasion was significantly different between the two groups; furthermore, early distant recurrence was more frequent in the Ret-group.

CONCLUSIONS

The reticular pattern around SMA is an important prognostic factor related to frequent distant recurrence in patients with pancreatic cancer.

Clinical Significance of Neoadjuvant Chemotherapy With Gemcitabine Plus S-1 for Resectable Pancreatic Ductal Adenocarcinoma

BACKGROUND/AIM

Little is known about the efficacy of neoadjuvant chemotherapy (NAC) with gemcitabine plus S-1 (GS) for patients with resectable pancreatic ductal adenocarcinoma (R-PDAC). The aim of this study was to investigate differences in the long-term outcome of patients with R-PDAC undergoing pancreatectomy with and without NAC-GS to clarify the clinical significance of NAC-GS.

PATIENTS AND METHODS

A total of 77 patients with R-PDAC who were scheduled for pancreatectomy between January 2012 and December 2017 were enrolled. Of these patients, 39 received NAC-GS (GS group) and 38 had upfront surgery (UFS group).

RESULTS

Among the 77 patients, one patient in each group did not undergo pancreatectomy due to intraoperative non-curative factors. Median tumor size and the number of lymph nodes with metastasis were significantly lower in the GS group than in the UFS group (p=0.002 and p=0.017). However, the 5-year overall survival rate was similar in the two groups (26.1% versus 21.5%, p=0.930).

CONCLUSION

NAC-GS may not be recommended for patients with R-PDAC since it does not seem to offer any survival benefits.

Radiomics Facilitates Candidate Selection for Irradiation Stents Among Patients With Unresectable Pancreatic Cancer

Purpose: To develop a model to select appropriate candidates for irradiation stent placement among patients with unresectable pancreatic cancer with malignant biliary obstruction (UPC-MBO). Methods: This retrospective study included 106 patients treated with an irradiation stent for UPC-MBO. These patients were randomly divided into a training group (74 patients) and a validation group (32 patients). A clinical model for predicting restenosis-free survival (RFS) was developed with clinical predictors selected by univariate and multivariate analyses. After integrating the radiomics signature, a combined model was constructed to predict RFS. The predictive performance was evaluated with the concordance index (C-index) in both the training and validation groups. The median risk score of progression in the training group was used to divide patients into high- and low-risk subgroups. Results: Radiomics features were integrated with clinical predictors to develop a combined model. The predictive performance was better in the combined model (C-index, 0.791 and 0.779 in the training and validation groups, respectively) than in the clinical model (C-index, 0.673 and 0.667 in the training and validation groups, respectively). According to the median risk score of 1.264, the RFS was significantly different between the high- and low-risk groups (p < 0.001 for the training group, and p = 0.016 for the validation group). Conclusions: The radiomics-based model had good performance for RFS prediction in patients with UPC-MBO who received an irradiation stent. Patients with slow progression should consider undergoing irradiation stent placement for a longer RFS.