Does the mechanism of lymph node invasion affect survival in patients with pancreatic ductal adenocarcinoma?

Histopathological evaluation after pancreatic surgery: Comparison of the results of HPB-specific pathologists and non-specific pathologists

Objectives

The aim of this study was to compare the results of the evaluation of HPB-specific pathologists and general pathologists on the specimens of patients who underwent pancreaticoduodenectomy by the same surgical team.

Material and Methods

The pathological results of 159 patients who underwent pancreaticoduodenectomy (PD) in the periampullary region was retrospectively examined. Histopathological evaluation results of HPB-specific pathologist (S group) and other pathologists (NS group) were compared. Tumor size (mm), total lymph nodes, metastatic lymph nodes, surgical margin positive/negative (RO/R1/R2 resection) and data of patients who underwent vascular resection were evaluated.

Results

The specimens of 91 patients were examined by a HPB-specific pathologist (S group), and the specimens of 68 patients were examined by non-specific pathologists (NS group). When compared in terms of the average total number of lymph nodes and metastatic lymph nodes dissected, a statistically significant result was observed (p= 0.04, p <0.01 respectively). Additionally, surgical margin positivity (R1) was found to be statistically higher in the S group (p= 0.02).

Conclusion

In order for the success of HPB surgery to be reflected in the clinic, it is of great importance that the specimens are examined by HPBspecific pathologists.

Feasibility of a CT-based lymph node radiomics nomogram in detecting lymph node metastasis in PDAC patients

Objectives

To investigate the potential value of a contrast enhanced computed tomography (CECT)-based radiological-radiomics nomogram combining a lymph node (LN) radiomics signature and LNs’ radiological features for preoperative detection of LN metastasis in patients with pancreatic ductal adenocarcinoma (PDAC).

Materials and methods

In this retrospective study, 196 LNs in 61 PDAC patients were enrolled and divided into the training (137 LNs) and validation (59 LNs) cohorts. Radiomic features were extracted from portal venous phase images of LNs. The least absolute shrinkage and selection operator (LASSO) regression algorithm with 10-fold cross-validation was used to select optimal features to determine the radiomics score (Rad-score). The radiological-radiomics nomogram was developed by using significant predictors of LN metastasis by multivariate logistic regression (LR) analysis in the training cohort and validated in the validation cohort independently. Its diagnostic performance was assessed by receiver operating characteristic curve (ROC), decision curve (DCA) and calibration curve analyses.

Results

The radiological model, including LN size, and margin and enhancement pattern (three significant predictors), exhibited areas under the curves (AUCs) of 0.831 and 0.756 in the training and validation cohorts, respectively. Nine radiomic features were used to construct a radiomics model, which showed AUCs of 0.879 and 0.804 in the training and validation cohorts, respectively. The radiological-radiomics nomogram, which incorporated the LN Rad-score and the three LNs’ radiological features, performed better than the Rad-score and radiological models individually, with AUCs of 0.937 and 0.851 in the training and validation cohorts, respectively. Calibration curve analysis and DCA revealed that the radiological-radiomics nomogram showed satisfactory consistency and the highest net benefit for preoperative diagnosis of LN metastasis.

Conclusions

The CT-based LN radiological-radiomics nomogram may serve as a valid and convenient computer-aided tool for personalized risk assessment of LN metastasis and help clinicians make appropriate clinical decisions for PADC patients.

Rethinking the TNM Classification Regarding Direct Lymph Node Invasion in Pancreatic Ductal Adenocarcinoma

Simple Summary

Due to the rising burden of pancreatic cancer and poor outcomes, a precise, post-operative cancer staging for further and individualized therapy is needed. In the latest cancer classification system, the lymph node invasion mechanism is not addressed. Due to different outcomes regarding the lymph node invasion, we suggest a rethinking of the current system.

Abstract

Mechanisms of lymph node invasion seem to play a prognostic role in pancreatic ductal adenocarcinoma (PDAC) after resection. However, the 8th edition of the TNM classification of the American Joint Committee on Cancer (AJCC) does not consider this. The aim of this study was to analyse the prognostic role of different mechanisms of lymph node invasion on PDAC. One hundred and twenty-two patients with resected PDAC were examined. We distinguished three groups: direct (per continuitatem, Nc) from the main tumour, metastasis (Nm) without any contact to the main tumour, and a mixed mechanism (Ncm). Afterwards, the prognostic power of the different groups was analysed concerning overall survival (OS). In total, 20 patients displayed direct lymph node invasion (Nc = 16.4%), 44 were classed as Nm (36.1%), and 21 were classed as Ncm (17.2%). The difference in OS was not statistically significant between N0 (no lymph node metastasis, n = 37) and Nc (p = 0.134), while Nm had worse OS than N0 (p < 0.001). Direct invasion alone had no statistically significant effect on OS (p = 0.885). Redefining the N0 stage by including Nc patients showed a more precise OS prediction among N stages (p = 0.001 vs. p = 0.002). Nc was more similar to N0 than to Nm; hence, we suggest a rethinking of TNM classification based on the mechanisms of lymph node metastases in PDAC. Overall, this novel classification is more precise.

Minimally Invasive Versus Open Radical Antegrade Modular Pancreatosplenectomy: A Meta-Analysis

BACKGROUND

Radical antegrade modular pancreatosplenectomy (RAMPS) was introduced to improve the tangential resection margin rates and N1 node clearance following resection of malignancies of the pancreatic body and tail. Owing to its technical complexity, minimally invasive RAMPS (MI-RAMPS) has only been reported by a few centers worldwide. We performed this meta-analysis to compare both short- and long-term outcomes between open RAMPS (O-RAMPS) and minimally invasive RAMPS (MI-RAMPS).

METHODS

A systematic search of the electronic databases PubMed, Medline (via PubMed), Cochrane Register of Controlled Trials (CENTRAL), EMBASE, Scopus and Web of Science was performed to identify eligible studies published in the English language regardless of study design. The outcomes of interest were operation time, estimated blood loss, transfusion rates, overall complications, Grade B/C post-operative pancreatic fistula (POPF) rates, post-pancreatectomy hemorrhage (PPH), delayed gastric emptying (DGE), length of stay (LOS), R0 resection rates, lymph node (LN) yield and overall survival (OS).

RESULTS

Five non-randomized studies comprising of a total 229 patients (89 MI-RAMPS, 140 O-RAMPS) were included for analysis. Intra-operative blood loss was observed to be significantly reduced in MI-RAMPS as compared to O-RAMPS (MD -256.16, P < 0.001), while LN yield was higher in O-RAMPS as compared to MI-RAMPS (MD -2.73, P = 0.02). There were no statistically significant differences observed for the other perioperative, oncologic and survival outcomes.

CONCLUSIONS

This meta-analysis provides early evidence to suggest that MI-RAMPS may produce comparable short- and long-term outcomes to O-RAMPS, when undertaken by appropriately skilled surgeons in well-selected patients. Further large-scale prospective studies are required to corroborate these findings.

Resected pancreatic adenocarcinoma: An Asian institution's experience

BACKGROUND

Pancreatic adenocarcinoma (PDAC) is highly lethal. Surgery offers the only chance of cure, but 5-year overall survival (OS) after surgical resection and adjuvant therapy remains dismal. Adjuvant trials were mostly conducted in the West enrolling fit patients. Applicability to a general population, especially Asia has not been described adequately.

AIM

We aimed to evaluate the clinical outcomes, prognostic factors of survival, pattern, and timing of recurrence after curative resection in an Asian institution.

METHODS AND RESULTS

The clinicopathologic and survival outcomes of 165 PDAC patients who underwent curative resection between 1998 and 2013 were reviewed retrospectively. Median age at surgery was 62.0 years. 55.2% were male, and 73.3% had tumors involving the head of pancreas. The median OS of the entire cohort was 19.7 months. Median OS of patients who received adjuvant chemotherapy was 23.8 months. Negative predictors of survival include lymph node ratio (LNR) of >0.3 (HR = 3.36, P = .001), tumor site involving the body or tail of pancreas (HR = 1.59, P = .046), presence of perineural invasion (PNI) (HR = 2.36, P = .018) and poorly differentiated/undifferentiated tumor grade (HR = 1.86, P = .058). The median time to recurrence was 8.87 months, with 66.1% and 81.2% of patients developing recurrence at 12 months and 24 months respectively. The most common site of recurrence was the liver.

CONCLUSION

The survival of Asian patients with resected PDAC who received adjuvant chemotherapy is comparable to reported randomized trials. Clinical characteristics seem similar to Western patients. Hence, geographical locations may not be a necessary stratification factor in RCTs. Conversely, lymph node ratio and status of PNI ought to be incorporated.

Validation and modification of the AJCC 8th TNM staging system for pancreatic ductal adenocarcinoma in a Chinese cohort: A nationwide pancreas data center analysis

Objective

To validate the 8th edition of the American Joint Committee on Cancer (AJCC) staging system for pancreatic ductal adenocarcinoma (PDAC) in a Chinese cohort of radically resected patients and to develop a refined staging system for PDAC.

Methods

Data were collected from the China Pancreas Data Center (CPDC) for patients with resected PDAC in 2016 and 2017, and cancer-specific survival (CSS) was evaluated using the Kaplan-Meier method and log-rank test. Univariate and multivariate analyses based on Cox regression were performed to identify prognostic factors. The recursive partitioning analysis (RPA), Kaplan-Meier method, and log-rank test were performed on the training dataset to generate a proposed modification for the 8th TNM staging system utilizing the preoperative carbohydrate antigen (CA)19-9 level. Validation was performed for both staging systems in the validation cohort.

Results

A total of 1,676 PDAC patients were retrieved, and the median CSS was significantly different between the 8th TNM groupings, with no significant difference in survival between stage IB and IIA. The analysis of T and N stages demonstrated a better prognostic value in the N category. Multivariate analysis showed that the preoperative serum CA19-9 level was the strongest prognostic indicator among all the independent risk factors. All patients with CA19-9 >500 U/mL had similar survival, and we proposed a new staging system by combining IB and IIA and stratifying all patients with high CA19-9 into stage III. The modified staging system had a better performance for predicting CSS than the 8th AJCC staging scheme.

Conclusions

The 8th AJCC staging system for PDAC is suitable for a Chinese cohort of resected patients, and the N category has a better prognostic value than the T category. Our modified staging system has superior accuracy in predicting survival than the 8th AJCC TNM staging system.

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.

Radical antegrade modular pancreatosplenectomy (RAMPS) versus conventional distal pancreatectomy for left-sided pancreatic cancer: findings of a multicenter, retrospective, propensity score matching study

PURPOSE

Radical antegrade modular pancreatosplenectomy (RAMPS) has been reported to achieve high rates of a negative margin and resected metastatic lymph nodes. However, many studies have used historical controls and the results remain controversial. We conducted this study to compare the surgical and long-term outcomes of RAMPS vs. conventional distal pancreatectomy (DP).

METHODS

The subjects of this multicenter retrospective study were 106 patients who underwent curative resection for left-sided pancreatic cancer between 2012 and 2017. Overall survival (OS) and recurrence-free survival (RFS) rates were compared using Kaplan-Meier estimates.

RESULTS

The RAMPS group had more advanced T (T3/T4) and N stages (N1/N2) and a larger tumor size than the conventional group (T stage, p = 0.04; N stage, p = 0.02; tumor size, p = 0.04). The RAMPS group had more harvested metastatic lymph nodes (p = 0.02). After propensity-score matching, 37 patients from each group were included in the final analysis. There was no significant difference in RFS (p = 0.463) or OS (p = 0.383) between the groups. Multivariate analyses revealed the completion of chemotherapy to be an independent factor for RFS and OS (both p < 0.001).

CONCLUSIONS

There was no difference in the RFS or OS between RAMPS and conventional DP in this series. RAMPS may be an option for R0 resection of advanced tumors; however, postoperative chemotherapy has a greater influence than the surgical procedure on the prognosis of patients with pancreatic cancer.

Peritumoral lymph nodes in pancreatic cancer revisited; is it truly equivalent to lymph node metastasis?

BACKGROUND

Lymph node (LN) metastasis is a well-known poor prognostic factor of pancreatic cancer. LN metastasis, through direct invasion of tumor cell to peritumoral lymph nodes (PTLN), is treated as the same as those which spread through lymphatic channels. This study aimed to evaluate the impact of PTLN invasion on the oncologic outcome of pancreatic cancer.

METHODS

Five hundred and six patients who underwent operation for pancreatic ductal adenocarcinoma from 2012 to 2018 were reviewed. PTLN invasion was defined as direct invasion of tumor cells in contact with main tumor.

RESULTS

Among the 506 patients, 112 patients (22.1%) had PTLN invasion. PTLN invasion group (PTLNI) showed better disease-free survival than regional LN metastasis group (RLNM) and combined LN metastasis group (CLNM) (PTLNI 21 vs RLNM 11 vs CLNM 12 months, P = .003). There was no significant difference between N0 and PTLNI (PTLNI 21 vs N0 23 months, P = .999). In multivariate analysis, conventional LN metastasis was a significant factor compared to N0, but PTLN invasion was not (hazard ratio 0.786 [0.507-1.220], P = .283).

CONCLUSION

Because PTLN invasion does not adversely affect survival in the same way as LN metastasis does, pancreatic cancer-may be overstaged if PTLN invasion were dealt in the same manner as a metastatic LN. Therefore, PTLN invasion should be disregarded from current nodal staging system.

Large tumor size, lymphovascular invasion, and synchronous metastasis are associated with the recurrence of solid pseudopapillary neoplasms of the pancreas

BACKGROUND

Solid pseudopapillary neoplasms (SPNs) of the pancreas have low malignant potential. However, malignant SPNs are not fully understood.

METHODS

To evaluate risk factors affecting malignant potential, the clinicopathologic features of 375 surgically resected SPNs were compared.

RESULTS

Fifty (13.3%) had malignant histologic features. Twenty-seven and 22 had perineural and lymphovascular invasions, respectively. Adjacent organ invasion was noted in 9 cases. Recurrence occurred in 8 cases. The median recurrence time after surgical resection was 67 months and was associated with a higher pT category (P = 0.001), lymphovascular invasion (P < 0.001), and synchronous metastasis (P < 0.001). SPN patients with malignant histologic features had worse recurrence-free survival (RFS; 10-year survival rate, 73.2%) than those without malignant histologic features (96.3%; P = 0.01). Patients with a higher pT category (P = 0.04), synchronous metastasis (P < 0.01), and lymphovascular invasion (P < 0.01) had worse RFS. Lymphovascular invasion (P = 0.042) and a higher T category (P = 0.002) were poor prognostic factors for recurrence.

CONCLUSION

Lymphovascular invasion and a higher T category were worse prognostic factors for recurrence in SPN patients with malignant histologic features. For SPN patients with malignant histologic features, a longer follow-up may be required.

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

Background

Although lymph node metastasis is a poor prognostic factor in patients with pancreatic ductal adenocarcinoma (PDAC), our understanding of lymph node size in association with PDAC is limited. Increased nodal size in preoperative imaging has been used to detect node metastasis. We evaluated whether lymph node size can be used as a surrogate preoperative marker of lymph node metastasis.

Methods

We assessed nodal size and compared it to the nodal metastatic status of 200 patients with surgically resected PDAC. The size of all lymph nodes and metastatic nodal foci were measured along the long and short axis, and the relationships between nodal size and metastatic status were compared at six cutoff points.

Results

A total of 4,525 lymph nodes were examined, 9.1% of which were metastatic. The mean size of the metastatic nodes (long axis, 6.9±5.0 mm; short axis, 4.3±3.1 mm) was significantly larger than that of the non-metastatic nodes (long axis, 5.0±4.0 mm; short axis, 3.0±2.0 mm; all p<.001). Using a 10 mm cutoff, the sensitivity, specificity, positive predictive value, overall accuracy, and area under curve was 24.8%, 88.0%, 17.1%, 82.3%, and 0.60 for the long axis and 7.0%, 99.0%, 40.3%, 90.6%, and 0.61 for the short axis, respectively.

Conclusions

The metastatic nodes are larger than the non-metastatic nodes in PDAC patients. However, the difference in nodal size was too small to be identified with preoperative imaging. The performance of preoperative radiologic imaging to predict lymph nodal metastasis was not good. Therefore, nodal size cannot be used a surrogate preoperative marker of lymph node metastasis.

Validation of the American Joint Committee on Cancer 8th edition staging system for the pancreatic ductal adenocarcinoma

BACKGROUND & AIMS

The American Joint Commission on Cancer (AJCC) 8th edition staging system for pancreatic ductal adenocarcinoma (PDA) contains several significant changes. This study aimed to validate the AJCC 8th edition staging system of PDA.

METHODS

We analyzed patients with resected PDA between 2001 and 2017 using the Korean Pancreatic Cancer (K-PaC) registry. Overall survival (OS) was estimated using the Kaplan-Meier survival curves and compared via the log-rank test.

RESULTS

In total, 701 resected PDA patients were identified. During a median follow-up of 24.5 months, the median OS was 21.7 months. Meanwhile, the median OS of each stage according to the AJCC 8th edition was 73.5 months (stage IA), 41.9 months (stage IB), 24.2 months (stage IIA), 18.3 months (stage IIB), and 16.8 months (stage III). However, the new N-category (pN1 vs. pN2) did not subdivide prognosis, although the lymph node ratio (i.e., the ratio of the number of LN involved to the number of examined LN) did. Although pT3 and pN2 belong under stage III, pN2 has a significantly longer median OS than pT3 (16.9 months vs 11.2 months; p < 0.01).

CONCLUSION

The AJCC 8th edition staging system appropriately stratifies the prognosis of PDA patients. However, the cutoff of the N-category is not statistically valid, and the new stage III includes a heterogeneous category (pN2 and pT4). Therefore, we propose that stage III be divided into stage IIIA (Tany N2 M0) and stage IIIB (T4 Nany M0).

Pathomorphological features of metastatic lymph nodes as predictors of postoperative prognosis in pancreatic cancer

To investigate the pathological features of metastatic lymph nodes (LN) in pancreatic ductal adenocarcinoma (PDAC) and to determine factors with prognostic implications.Metastatic LN status is a proven significant factor for predicting postoperative prognosis in pancreatic cancer patients. However, the effective prognostic criteria regarding metastatic LNs for such disease remain unknown.We retrospectively reviewed 98 patients with R0/1 resection for PDAC. All metastatic LNs were evaluated for the pathomorphological features of metastasis and analyzed in terms of postoperative outcomes. Various morphological patterns of metastasis were assessed in 440 positive LNs and then classified into 4 groups: common type, direct type (continuously invaded by the main tumor), scatter type (multiple tumor clusters among the normal LN tissues), and isolated tumor cell (ITC).The pathological stage was defined as stage IIA in 10% and IIB in 90% patients. Common-type metastasis was noted in 55% positive LNs of 75% node-positive patients; direct type in 36% LNs of 69% patients; scatter type in 5% LNs of 14% patients; and ITCs in 5% LNs of 18% patients. Significant difference was noted only in recurrence-free survival (RFS) but not in overall survival (OS) in the common-type; only in OS but not in RFS for the scatter type; and neither in RFS nor OS for both direct type and ITC. Multivariate analysis revealed that only LN ratio and curability were independent predictive factors of poor.The tumor distribution patterns in metastatic LNs are the postoperative prognostic factors in pancreatic cancer.

Multinational validation of the American Joint Committee on Cancer 8th edition pancreatic cancer staging system in a pancreas head cancer cohort

BACKGROUND

The aim of the present study was to compare the 7th and 8th editions of the American Joint Committee on Cancer (AJCC) staging system for pancreas head cancer and to validate the 8th edition using three multinational tertiary center data.

METHODS

Data of 2,864 patients with pancreas head cancer were collected from Korea (571), Japan (824), and the USA (1,469). Survival analysis was performed to compare the 7th and 8th editions. Validation was performed by log-rank tests and test for trend repeated 1,000 times with random sets.

RESULTS

In the 7th edition, 4.1%, 3.1%, 18.6%, 67.5%, 3.6%, and 3.1% were stage IA, IB, IIA, IIB, III, and IV. In the 8th edition, 8.8%, 13.9%, 3.1%, 38.2%, 32.9%, and 3.1% were stage IA, IB, IIA, IIB, III, and IV, respectively. The change in T category downstaged 459 patients from IIA to the new IA and IB. The new N2 category upstaged 856 patients from the former IIB to III. The 7th edition reversely stratified IA and IB. The 8th edition corrected this mis-stratification of the 7th edition, but lacked discriminatory power between IB and IIA (P = 0.271). Validation using the log-rank showed that the 8th edition provided better discrimination in 6.387 test sets among 10 tests. The test for trend validated the 8th edition to stratify stages in correct order more often (7.815/10).

CONCLUSION

The 8th edition provides more even distribution with more powerful discrimination compared to the 7th edition.

Evaluation of the prognostic value of the new AJCC 8th edition staging system for patients with pancreatic adenocarcinoma; a need to subclassify stage III?

BACKGROUND

There have been several proposed changes for the 8th edition of the American Joint Commission on Cancer (AJCC) for pancreatic adenocarcinoma. The aim of this study was to evaluate the prognostic value of the new staging system for patients with pancreatic adenocarcinoma, especially in stage III patients.

METHODS

We analysed the data of patients newly diagnosed with pancreatic adenocarcinoma between 2008 and 2016 at our hospital. Patients were staged according to 7th edition AJCC criteria, as well as the new 8th edition staging system. The pathologic stage was used in the surgical cases, and the clinical stage, determined by radiographic findings, was used in the unresectable cases.

RESULTS

Five hundred two patients were identified who met the inclusion criteria. In node-negative patients, there were no significant differences in survival among T 1, 2 and 3 groups according to the 8th edition. The survival rates of patients with N1 (1-3 positive nodes) and N2 (≥4 positive nodes) disease, according to 8th edition, were significantly different (p < 0.001). Although N2 and T4 patients are both stage III according to the new staging system, N2 patients had a better survival rate than T4 patients (p = 0.038). The new staging system stratifies patients more evenly across stages without sacrificing the prognostic accuracy.

CONCLUSIONS

The AJCC 8th edition has some advantages over the previous version. However, patients with N2 and T4, who have been integrated into stage III, showed different treatment modalities and prognoses, and we proposed dividing stage III into IIIA (T1-3N2M0) and IIIB (T4N_anyM0).

Prognostic stratification of resected pancreatic ductal adenocarcinoma: Past, present, and future

Pancreatic ductal adenocarcinoma (PDAC) is the digestive cancer with the poorest prognosis, with a 5-year overall survival rate of 7%. Complete surgical resection followed by adjuvant chemotherapy is the only treatment with curative intent. However, many patients with an apparently localized disease who may undergo primary tumor resection already have micro-metastatic disease and will promptly develop metastases. Considering the significant rate of morbidity and mortality upon pancreatic surgery, the pre-operative identification of patients with an aggressive disease is therefore a major clinical issue. Although tumor size, differentiation, margins, and lymph node invasion are the main "classical" prognostic factors, they are not sufficient to fully predict early disease recurrence. In the last decade, multi-omics high-throughput analyses have provided a new insight into PDAC biology and have led to the description of multiple molecular subtypes, with a significant prognostic value for most of them, but that have not yet been transposed to routine clinical practice, mainly due to poor availability of tumor tissue material prior to surgical resection. In this review, we provide an overview of the current status of clinico-pathological and molecular biomarkers (tumor and blood) to predict early recurrence, and their implications for clinical practice and future research development.

Can physician gestalt predict survival in patients with resectable pancreatic adenocarcinoma?

PURPOSE

Clinician gestalt may hold unexplored information that can be capitalized upon to improve existing nomograms. The study objective was to evaluate physician ability to predict 2-year overall survival (OS) in resected pancreatic ductal adenocarcinoma (PDAC) patients based on pre-operative clinical characteristics and routine CT imaging.

METHODS

Ten surgeons and two radiologists were provided with a clinical vignette (including age, gender, presenting symptoms, and pre-operative CA19-9 when available) and pre-operative CT scan for 20 resected PDAC patients and asked to predict the probability of each patient reaching 2-year OS. Receiver operating characteristic curves were used to assess agreement and to compare performance with an established institutional nomogram.

RESULTS

Ten surgeons and 2 radiologists participated in this study. The area under the curve (AUC) for all physicians was 0.707 (95% CI 0.642-0.772). Attending physicians with > 5 years experience performed better than physicians with < 5 years of clinical experience since completion of post-graduate training (AUC = 0.710, 95% CI [0.536-0.884] compared to AUC = 0.662, 95% CI [0.398-0.927]). Radiologists performed better than surgeons (AUC = 0.875, 95% CI [0.765-0.985] compared to AUC = 0.656, 95% CI [0.580-0.732]). All but one physician outperformed the clinical nomogram (AUC = 0.604).

CONCLUSIONS

This pilot study demonstrated significant promise in the quantification of physician gestalt. While PDAC remains a difficult disease to prognosticate, physicians, particularly those with more clinical experience and radiologic expertise, are able to perform with higher accuracy than existing nomograms in predicting 2-year survival.

Histologic Tumor Grade and Preoperative Bilary Drainage are the Unique Independent Prognostic Factors of Survival in Pancreatic Ductal Adenocarcinoma Patients After Pancreaticoduodenectomy

BACKGROUND AND AIM

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal types of cancer; most patients die during the first 6 months after diagnosis. With a 5% 5-year survival rate, is the fourth leading cause of cancer death in developed countries. In this regard, several clinical, histopathologic and biological characteristics of the disease favoring long-term survival after pancreaticoduodenectomy have been reported to be significant prognostic factors. Despite the availability of this information, there is no consensus about the different prognostic factors reported in the literature, probably due to variations in patient selection, methods, and sample size studied. The aim of this study was to identify the clinical and pathologic features associated to prognosis of the disease after pancreaticoduodenectomy.

MATERIALS AND METHODS

The clinical and pathologic data from 78 patients who underwent a potentially curative resection for PDAC at our institution between 2003 and 2014 were analyzed retrospectively.

RESULTS

Overall, high-grade PDAC cases showed larger tumor size (P=0.009) and a higher frequency of deaths in association with a nonsignificantly shortened patient overall survival (median of 12.5 vs. 21.7 mo; P=0.065) as compared with low-grade PDAC patients. High histologic grade (P=0.013), preoperative drainage on the main bile duct (P=0.014) and absence of adjuvant therapy (P=0.035) were associated with a significantly poorer outcome. Overall survival multivariate analysis showed histologic grade (P=0.019) and bile duct preoperative drainage (P=0.016) as the sole independent variables predicting an adverse outcome.

CONCLUSIONS

Our results indicate that histologic tumor grade and preoperative biliary drainage are the only significant independent prognostic factors in PDAC patients after pancreatectomy.

The More the Better-Lower Rate of Stage Migration and Better Survival in Patients With Retrieval of 20 or More Regional Lymph Nodes in Pancreatic Cancer: A Population-Based Propensity Score Matched and Trend SEER Analysis

OBJECTIVE

The aim of this study was to assess the influence of regional lymph node (RLN) retrieval on stage migration and survival in pancreatic cancer.

METHODS

A total of 7685 stage I and II pancreatic cancer patients were identified in the Surveillance, Epidemiology, and End Results database in 2004-2011. The impact of RLN was assessed using Cox regression, propensity score methods, and joinpoint regression.

RESULTS

In 3079 patients, 1 to 10 RLNs were retrieved; in 2799 patients, 11 to 19 RLNs, and in 1807 patients, 20+ RLNs. The rate of node-positive pancreatic cancer increased with the number of retrieved RLN. This trend continued beyond 10 retrieved RLN (P < 0.001). In unadjusted analysis, retrieval of RLN did not influence survival (P = 0.178). When adjusting for significant bias in staging variables (P < 0.001), retrieval of 20+ RLNs compared to 11 to 19 RLNs was associated with an increased survival in node-negative (hazard ratio, 0.78; 95% confidence interval, 0.62-0.98; P = 0.033) and node-positive cancer (hazard ratio, 0.83; 95% confidence interval, 0.74-0.93; P = 0.002).

CONCLUSIONS

This population-based propensity score-adjusted investigation demonstrated that more retrieved RLNs in pancreatic cancer decreases the rate of stage migration and improves the oncological outcome in node-negative and positive cancer. Contradictory results may be explained by a bias in the cancer characteristics for a different extent of RLN retrieval.

Staging of pancreatic cancer based on the number of positive lymph nodes

BACKGROUND

The International Study Group on Pancreatic Surgery has stated that at least 12 lymph nodes should be evaluated for staging of pancreatic cancer. The aim of this population-based study was to evaluate whether the number of positive lymph nodes refines staging.

METHODS

Patients who underwent pancreatectomy for stage I-II pancreatic cancer between 2004 and 2012 were identified from the Surveillance, Epidemiology, and End Results database. The predictive value of the number of positive lymph nodes for survival was assessed by generalized receiver operating characteristic (ROC) curve analysis and propensity score-adjusted Cox regression analysis.

RESULTS

Some 5036 patients were included, with a median of 18 (i.q.r. 15-24) lymph nodes examined. Positive lymph nodes were found in 3555 patients (70·6 per cent). The median duration of follow-up was 15 (i.q.r. 8-28) months. ROC curve analysis revealed that two positive lymph nodes best discriminated overall survival. Patients with one or two positive lymph nodes (pN1a) and those with three or more positive lymph nodes (pN1b) had an increased risk of overall mortality compared with patients who were node-negative (pN0): hazard ratio (HR) 1·47 (95 per cent c.i. 1·33 to 1·64) and HR 2·01 (1·82 to 2·22) respectively. These findings were confirmed by propensity score-adjusted Cox regression analysis. The 5-year overall survival rates were 39·8 (95 per cent c.i. 36·5 to 43·3) per cent for patients with pN0, 21·0 (18·6 to 23·6) per cent for those with pN1a and 11·4 (9·9 to 13·3) per cent for patients with pN1b disease.

CONCLUSION

The number of positive lymph nodes in the resection specimen is a prognostic factor in patients with pancreatic cancer.

Prognostic impact of nodal statuses in patients with pancreatic ductal adenocarcinoma

BACKGROUND

The present study aimed to clarify the prognostic impact of nodal statuses in pancreatic ductal adenocarcinoma (PDAC) after potentially curative pancreatectomy.

METHODS

In 110 patients with >10 examined lymph nodes (ELNs), we investigated how nodal statuses were associated with postoperative survival. Nodal statuses included the number of positive LNs (PLNs); the ratio of PLNs to ELNs (lymph node ratio; LNR); and the location of regional LN metastases, classified as group one (peripancreatic area) and group 2 (outside the peripancreatic area). The maximum χ² value, provided by a Cox proportional hazards model, was used to determine the optimal cutoff value for the number of PLNs and the LNR.

RESULTS

The median numbers of ELNs and metastatic LNs were 33 and 2, respectively. Median survival was longer in patients with ≤3 PLNs (37.5 months), LNR <0.11 (36.1 months), and group 1 LN metastases (37.5 months) compared to in patients with ≥4 PLNs (23.7 months), LNR ≥0.11 (23.9 months), and group 2 LN metastases (22.8 months), respectively. Multivariate analyses revealed that all three investigated nodal statuses were independent factors associated with survival: HR of 2.38 and p = 0.0006 for the location of LN metastases, HR of 1.92 and p = 0.0071 for the number of PLNs, and HR of 1.89 and p = 0.010 for the LNR.

CONCLUSIONS

Three nodal statuses-the number of PLNs, the LNR, and the location of LN metastases-could stratify postoperative survival among PDAC patients with an adequate number of examined LNs after pancreatectomy.

Factors predicting adequate lymph node yield in patients undergoing pancreatoduodenectomy for malignancy

Background

Most pancreatoduodenectomy resections do not meet the minimum of 12 lymph nodes recommended by the American Joint Committee on Cancer for accurate staging of periampullary malignancies. The purpose of this study was to investigate factors affecting the likelihood of adequate nodal yield in pancreatoduodenectomy specimens subject to routine pathological assessment.

Methods

Six hundred sixty-two patients subject to pancreatoduodenectomy between 1990 and 2013 for pancreatic, ampullary, and common bile duct cancers were reviewed. Predictors of yielding at least 12 lymph nodes were evaluated with a logistic regression model, and a survival analysis was carried out to verify the prognostic implications of nodal counts.

Results

The median number of evaluated nodes was 17 (interquartile range 11 to 25), and less than 12 lymph nodes were reported in surgical specimens of 179 (27 %) patients. Tumor diameter ≥20 mm (odds ratio [OR] 2.547, 95 % confidence interval [CI] 1.225 to 5.329, P = 0.013), lymph node metastases (OR 2.642, 95 % CI 1.378 to 5.061, P = 0.004), and radical lymphadenectomy (OR 5.566, 95 % CI 2.041 to 15.148, P = 0.01) were significant predictors of retrieving 12 or more lymph nodes. Lymph node counts did not influence the overall prognosis of the patients. However, a subgroup analysis carried out for individual cancer sites demonstrated that removing at least 12 lymph nodes is associated with better prognosis for pancreatic cancer.

Conclusions

Few variables affect adequate nodal yield in pancreatoduodenectomy specimens subject to routine pathological assessment. Considering the ambiguities related to the only modifiable factor identified, appropriate pathology training should be considered to increase nodal yield rather than more aggressive lymphatic dissection.

Identification of an N staging system that predicts oncologic outcome in resected left-sided pancreatic cancer

In this study, we investigated which N staging system was the most accurate at predicting survival in pancreatic cancer patients.Lymph node (LN) metastasis is known to be one of the important prognostic factors in resected pancreatic cancer. There are several LN evaluation systems to predict oncologic impact.From January 1992 to December 2014, 77 medical records of patients who underwent radical pancreatectomy for left-sided pancreatic cancer were reviewed retrospectively. Clinicopathologic variables including pN stage, total number of retrieved LNs (N-RLN), lymph node ratio (LNR), and absolute number of LN metastases (N-LNmet) were evaluated. Disease-free survival (DFS) and disease-specific survival (DSS) were analyzed according to these 4 LN staging systems.In univariate analysis, pN stage (pN0 vs pN1: 17.5 months vs 7.9 months, P = 0.001), LNR (<0.08 vs ≥0.08: 17.5 months vs 4.4 months, P < 0.001), and N-LNmet (#N = 0 vs #N = 1 vs #N≥2: 17.5 months vs 11.0 months vs 6.4 months, P = 0.002) had a significant effect on DFS, whereas the pN stage (pN0 vs pN1: 35.3 months vs 16.7 months, P = 0.001), LNR (<0.08 vs ≥0.08: 37.1 months vs 15.0 months, P < 0.001), and N-LNmet (#N = 0 vs #N = 1 vs #N≥2: 35.3 months vs 18.4 months vs 16.4 months, P = 0.001) had a significant effect on DSS. In multivariate analysis, N-LNmet (#N≥2) was identified as an independent prognostic factor of oncologic outcome (DFS and DSS: Exp (β) = 2.83, P = 0.001, and Exp (β) = 3.17, P = 0.001, respectively).Absolute number of lymph node metastases predicted oncologic outcome in resected left-sided pancreatic cancer patients.

Advances in the Surgical Management of Resectable and Borderline Resectable Pancreas Cancer

Successful surgical resection offers the only chance for cure in patients with pancreatic cancer. However, pancreatic resection is feasible in less than 20% of the patients. In this review, the current state of surgical management of pancreatic cancer is discussed. The definition of resectability based on cross-sectional imaging and the technical aspects of surgery, including vascular resection and/or reconstruction, management of aberrant vascular anatomy and extent of lymphadenectomy, are appraised. Furthermore, common pancreatic resection-specific postoperative complications and their management are reviewed.

Concurrent gemcitabine+S-1 neoadjuvant chemotherapy contributes to the improved survival of patients with small borderline-resectable pancreatic cancer tumors

PURPOSES

In the surgical treatment of pancreatic cancer, margin-negative status is one of the most important determinants of survival. We conducted this study to explore surgical margin status as well as other factors affecting the survival of borderline-resectable pancreatic cancer (BRPC) patients who received neoadjuvant chemotherapy with gemcitabine and S-1.

METHODS

Eighteen BRPC patients were prospectively treated with concurrent gemcitabine and S-1 neoadjuvant chemotherapy (NAC+) and 15 of these patients underwent resection. We evaluated the safety and efficacy of this treatment regimen by comparing the outcomes of these patients with those of 19 BRPC patients who did not receive neoadjuvant chemotherapy (NAC-) during the same period.

RESULTS

Fifteen (83 %) of the NAC+ patients underwent pancreatectomy. The remaining three patients (17 %) had regional tumor progression or liver metastasis. Of the 15 NAC+ patients who underwent resection, 3 (20 %) had margin-positive status, whereas 9 of the 19 (43 %) NAC- patients had margin-positive status (p = 0.002). However, disease-free survival and overall survival were similar in the two groups (MST 21.7 vs. 21.1 months). NAC+ patients with tumors smaller than 30 mm had favorable overall survival (MST 43.9 vs. 23.1 months, p = 0.0321). Most recurrences developed at distant sites rather than locally in both groups.

CONCLUSIONS

In the neoadjuvant setting, gemcitabine and S-1 improved the negative surgical margin rate in BRPC patients, but it did not improve survival. Thus, neoadjuvant chemotherapy should be given to BRPC patients at an earlier stage.

The lymphatic system and pancreatic cancer

This review summarizes current knowledge of the biology, pathology and clinical understanding of lymphatic invasion and metastasis in pancreatic cancer. We discuss the clinical and biological consequences of lymphatic invasion and metastasis, including paraneoplastic effects on immune responses and consider the possible benefit of therapies to treat tumors that are localized to lymphatics. A review of current techniques and methods to study interactions between tumors and lymphatics is presented.

Substaging of Lymph Node Status in Resected Pancreatic Ductal Adenocarcinoma Has Strong Prognostic Correlations: Proposal for a Revised N Classification for TNM Staging

BACKGROUND

The current tumor-node-metastasis staging system for the pancreas does not incorporate the number of lymph nodes (LNs) with metastasis.

METHODS

Among 1649 pancreaticoduodenectomies, 227 stringently defined pancreatic ductal adenocarcinomas (PDACs) that had undergone a specific approach of LN harvesting were analyzed for the prognostic value of LN substaging protocols used for other gastrointestinal (GI) organs.

RESULTS

The median number of LNs harvested was 18, and the median number of LNs with metastasis was 3. Lymph node metastasis was detected in 175 cases (77 %). The number of LNs involved correlated significantly with clinical outcome. When cases were substaged with the protocol already in use for the upper GI organs (N0: no metastasis, N1: metastasis to 1-2 LNs; N2: metastasis to ≥3 LNs), the median overall survival times were 35, 21, and 18 months, and the respective 3-year survival rates were 46, 34, and 20 % (p = 0.004). Analysis of the Surveillance, Epidemiology and End Results (SEER) database also confirmed the survival differences between these substages (median overall survival times of 23, 15, and 14 months and respective 3-year survival rates of 37, 22, and 18 %; p < 0.0001). The substaging protocol for the lower GI organs (N0: no metastasis; N1: metastasis to 1-3 LNs; N2: metastasis to ≥4 LNs) also was significant, with median overall survival times of 35, 21, 18 months and respective 3-year survival rates of 46, 26, and 23 %; p = 0.009). The association between higher N stage and shorter survival persisted with multivariate modeling for both protocols, although the prognostic value of the upper GI protocol appeared to be slightly stronger according to the Akaike Information Criterion method.

CONCLUSION

In conclusion, with proper LN harvesting, the LN metastasis rate in PDACs is very high (77 %). Substaging of LN metastasis has significant prognostic value and needs to be considered in the N staging of PDACs. The protocol already in use for other upper GI tract organs, which currently also is proven significant for ampulla, would be preferable, although the lower GI tract protocol also is applicable.

Pancreatic cancer patients with lymph node involvement by direct tumor extension have similar survival to those with node-negative disease

BACKGROUND

Lymph node (LN) involvement is a well-known poor prognostic factor in patients with pancreatic ductal adenocarcinoma (PDAC). However, there have been conflicting results on the significance of the mechanism of LN involvement, "direct" tumor invasion versus "metastatic," disease on patient survival.

METHODS

Clinicopathologic records from all patients who underwent resection for PDAC from 1990 to 2014 at a single-institution were reviewed.

RESULTS

Of the 385 total patients, there was tumor invasion outside of the pancreas in 289 (75.1%) patients. Overall, 239 (62.1%) had node-positive disease: 220 (92.0%) by "metastatic" involvement, 14 (5.9%) by "direct" tumor extension, and five (2.1%) by a mix of "metastatic" and "direct". There were no significant differences in clinicopathologic factors associated with PDAC survival between "metastatic" and "direct" LN patients. The median overall survival for the whole cohort was 31.1 months. Compared to overall survival in patients with LN-negative disease (median 40.7 months), those with LNs involved by "metastatic" spread was significantly shorter (median 25.7 months, P < 0.001), yet "direct" LN extension was similar (median 48.1 months, P = 0.719).

CONCLUSIONS

The mechanism of LN involvement affects PDAC prognosis. Patients with LNs involved by direct extension have similar survival to those with node-negative disease.

Reappraisal of Nodal Staging and Study of Lymph Node Station Involvement in Pancreaticoduodenectomy with the Standard International Study Group of Pancreatic Surgery Definition of Lymphadenectomy for Cancer

BACKGROUND

The prognostic role of lymph node (LN) dissection in pancreatic head ductal adenocarcinoma is still unclear. This study reappraised the value of the number of positive LNs and LN ratio in patients undergoing pancreaticoduodenectomy with standard lymphadenectomy according to the recent International Study Group of Pancreatic Surgery definition. In addition, the impact of nodal metastases stratified by LN stations was investigated.

STUDY DESIGN

After reviewing retrospectively clinical and pathologic data of 758 pancreaticoduodenectomies for pancreatic head ductal adenocarcinoma performed from 2002 through 2011, we extracted patients in whom the LN stations included in the International Study Group of Pancreatic Surgery definition had been sampled. Survival analysis was performed using univariate and multivariate models.

RESULTS

The study population consisted of 255 patients. Mean number of harvested LNs was 30.8. Factors with a significant prognostic impact on multivariate analysis were tumor grade, adjuvant therapy, number of positive LNs, LN metastases along station 14a-b (proximal superior mesenteric artery), and the number of metastatic LN stations. Patients with involvement of station 14a-b exhibited worse pathologic features, indicating more aggressive disease.

CONCLUSIONS

In patients receiving a uniform LN dissection, the number of positive LNs is superior to LN ratio for predicting survival. Lymph node metastases along the proximal superior mesenteric artery have a significant prognostic value, and an increasing number of metastatic stations are associated with a sharp decrease in survival. In future studies, clarification of the pattern of LN metastasis spread could offer valuable insight into the optimal treatment strategies, including selection of patients for neoadjuvant therapies.

Number of examined lymph nodes and nodal status assessment in pancreaticoduodenectomy for pancreatic adenocarcinoma

BACKGROUND

The accuracy of the assessment of the nodal status in resected cephalic pancreatic adenocarcinoma (PA) depends on the number of examined lymph nodes (NELN). This study assesses the impact of the NELN on N staging and survival and propose a minimal number of examined lymph nodes (MNELN) ensuring reliability of the pN status determination.

METHODS

188 consecutive patients treated by pancreaticoduodenectomy (PD) for PA. Correlations between NELN and survivals of pN0 and pN1 groups and with the rate of pN1 patients were studied. A probability model based on the binomial law was built to estimate the MNELN able to detect pN1 patients with a sensitivity ≥ 95%.

RESULTS

Overall and disease free 5-year survivals were 27.2% and 24.6% respectively. 135 patients (71.8%) were staged pN1. The median NELN was 17 (range 0-68). Overall and disease free survivals of pN1 patients were not related to NELN. The influence of NELN on survival in pN0 patients due to stage migration did not reach significance. The probability model showed that a MNELN of 16 nodes was required to detect pN1 patients with a sensitivity of 95%.

CONCLUSION

A MNELN of 16 is required to assess pN status and should be considered as a quality criterion in future studies and trials on PD for PA.

Dramatic Survival Benefit Related to R0 Resection of Pancreatic Adenocarcinoma in Patients With Tumor ≤25 mm in Size and ≤1 Involved Lymph Nodes

OBJECTIVES:

To evaluate i) the relative importance of R0 resection, tumor size and peripancreatic lymph node (LN) status are significant determinants of survival benefit following upfront surgery for pancreatic adenocarcinoma (PaCa), ii) whether R0 resection confers survival benefit in all patients or a patient subset with certain favorable prognostic factors.

METHODS:

Retrospective analysis of patients (2001–2010) who underwent planned potentially curative surgical resection without neoadjuvant therapy for PaCa.

RESULTS:

Among 154 patients, median survival following R0 (n=105) and R1 resections was 26.8 and 17.7 months, respectively (P=0.010). Tumor size and LN status were significant determinants of survival following R0 resection. There were no differences in survival based on tumor size and LN in patients with R1 resection. Median survival was 17.7 months following R1 resection and was 70.9 months (P<0.001) and 22.2 months (P=0.44) in patients with tumor ≤25 mm in size and ≤1 involved LN and in the remaining patients in the cohort respectively following R0 resection.

CONCLUSIONS:

R0 resection is associated with dramatic survival benefit over R1 resection in a subset of patients with tumor size ≤25 mm and ≤1 involved LN. These findings underscore the importance of R0 resection and careful patient selection for upfront surgery in patients with PaCa.

A contemporary analysis of survival for resected pancreatic ductal adenocarcinoma

INTRODUCTION

Survival after a resected pancreatic ductal adenocarcinoma (PDAC) appears to be improving. Yet, in spite of advancements, prognosis remains disappointing. This study analyses a contemporary experience and identifies features associated with survival.

METHODS

Kaplan-Meier analysis was conducted for 424 PDAC resections performed at two institutions (2001-2011). Multivariate analysis was performed to elicit characteristics independently associated with survival.

RESULTS

The median, 1-, and 5-year survivals were 21.3 m, 76%, and 23%, with 30/90-day mortalities of 0.7%/1.7%. 76% of patients received adjuvant therapy. Patients with major complications (Clavien Grade IIIb-IV) survived equivalently to patients with no complications (P = 0.33). The median and 5-year survival for a total pancreatectomy was 32.2 m/49%; for 90 'favourable biology' patients (R0/N0/M0) was 37.3 m/40%; and for IPMN (9% of series) was 21.2 m/46%. Elderly (>75 yo) and nonelderly patients had similar survival. Favorable prognostic features by multivariate analysis include lower POSSUM physiology score, R0 resection, absence of operative transfusion, G1/G2 grade, absence of lymphovascular invasion, T1/T2 stage, smaller tumor size, LN ratio <0.3, and receipt of adjuvant therapy.

CONCLUSION

This experience with resected PDAC shows decreasing morbidity and mortality rates along with modestly improving long-term survival, particularly for certain subgroups of patients. Survival is related to pathological features, pre-operative physiology, operative results and adjuvant therapy.

Pathologic staging of pancreatic, ampullary, biliary, and gallbladder cancers: pitfalls and practical limitations of the current AJCC/UICC TNM staging system and opportunities for improvement

Tumors of the ampulla-pancreatobiliary tract are encountered increasingly; however, their staging can be highly challenging due to lack of familiarity. In this review article, the various issues encountered in staging of these tumors at the pathologic level are evaluated and possible solutions for daily practice as well as potential improvements for future staging protocols are discussed. While N-stage parameters have now been well established (the number of lymph nodes required in pancreatoduodenectomies is 12), the T-staging has several issues: for the pancreas, the discovery of small cancers arising in intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs) necessitates the creation of substages of T1 (as T1a, b, and c); lack of proper definition of "peripancreatic soft tissue" and "common bile duct involvement" (as to which part is meant) makes T3 highly subjective. Increasing resectability of main vessels (portal vein) brings the need to redefine a "T" for such cases. For the ampulla, due to factors like anatomic complexity of the region and the under-appreciation of three-dimensional spread of the tumors in this area (in particular, the frequent extension into periduodenal soft tissues and duodenal serosa, which are not addressed in the current system and which require specific grossing approaches to document), the current T-staging lacks reproducibility and clinical relevance, and therefore, major revisions are needed. Recently proposed refined definition and site-specific subclassification of ampullary tumors highlight the areas for improvement. For the extrahepatic bile ducts, the staging schemes that use the depth of invasion may be more practical to circumvent the inconsistencies in the histologic layering of the ducts; better definition of terms like "periductal spread" is needed. For the gallbladder, since many gallbladder cancers are "unapparent" (found in clinically and grossly unsuspected cholecystectomies), establishing proper grossing protocols and adequate sampling are crucial. Since the gallbladder does not have the distinct layering of the other gastrointestinal organs, the definitions of Tis/T1a/T1b lack practicality, and therefore, "early gallbladder carcinoma" category proposed in high-risk regions may have to be recognized instead. Involvement of the Rokitansky-Aschoff sinuses should be a part of the evaluation and management of these early gallbladder cancers; for advanced cancers, documentation of hepatic versus serosal involvement is necessary. In summary, T-staging of ampulla-pancreatobiliary tract tumors has many challenges. Proper grossing and appreciation of histo-anatomic subtleties of this region are crucial in addressing these issues and achieving more applicable and clinically relevant staging systems in the future.

Ductal adenocarcinoma of the pancreatic head: A focus on current diagnostic and surgical concepts

Complete surgical resection still remains the only possibility of curing pancreatic cancer, however, only 10% of patients undergo curative surgery. Pancreatic resection currently remains the only method of curing patients, and has a 5-year overall survival rate between 7%-34% compared to a median survival of 3-11 mo for unresected cancer. Pancreatic surgery is a technically demanding procedure requiring highly standardized surgical techniques. Nevertheless, even in experienced hands, perioperative morbidity rates (delayed gastric emptying, pancreatic fistula etc.) are as high as 50%. Different strategies to reduce postoperative morbidity, such as different techniques of gastroenteric reconstruction (pancreatico-jejunostomy vs pancreatico-gastrostomy), intraoperative placement of a pancreatic main duct stent or temporary sealing of the main pancreatic duct with fibrin glue have not led to a significant improvement in clinical outcome. The perioperative application of somatostatin or its analogues may decrease the incidence of pancreatic fistulas in cases with soft pancreatic tissue and a small main pancreatic duct (< 3 mm). The positive effects of external pancreatic main duct drainage and antecolic gastrointestinal reconstruction have been observed to decrease the rate of pancreatic fistulas and delayed gastric emptying, respectively. Currently, the concept of extended radical lymphadenectomy has been found to be associated with higher perioperative morbidity, but without any positive impact on overall survival. However, there is growing evidence that portal vein resections can be performed with acceptable low perioperative morbidity and mortality but does not achieve a cure.

Current state of surgical management of pancreatic cancer

Pancreatic cancer is still associated with a poor prognosis and remains—as the fourth leading cause of cancer related mortality—a therapeutic challenge. Overall long-term survival is about 1–5%, and in only 10–20% of pancreatic cancer patients is potentially curative surgery possible, increasing five-year survival rates to approximately 20–25%. Pancreatic surgery is a technically challenging procedure and has significantly changed during the past decades with regard to technical aspects as well as perioperative care. Standardized resections can be carried out with low morbidity and mortality below 5% in high volume institutions. Furthermore, there is growing evidence that also more extended resections including multivisceral approaches, vessel reconstructions or surgery for tumor recurrence can be carried out safely with favorable outcomes. The impact of adjuvant treatment, especially chemotherapy, has increased dramatically within recent years, leading to significantly improved postoperative survival, making pancreatic cancer therapy an interdisciplinary approach to achieve best results.