Significance of perivascular soft tissue around the common hepatic and proximal superior mesenteric arteries arising after pancreaticoduodenectomy: evaluation with serial MDCT studies

CT Surveillance for Local Recurrence After Pancreatic Cancer Resection: Evaluation of Imaging Findings From the SAR Disease-Focused Panel Consensus Statement

Background: A Society of Abdominal Radiology (SAR) Pancreatic Ductal Adenocarcinoma (PDAC) Disease-Focused Panel (DFP) consensus statement described findings suspicious for local recurrence (LR) on surveillance imaging after PDAC resection. Objective: To evaluate the interreader agreement and predictive utility of potential imaging findings of LR on serial surveillance CT examinations after Whipple procedure for PDAC, using the SAR PDAC DFP consensus statement. Methods: This retrospective study included 126 patients (mean age, 68.5±10.3 years; 72 men, 54 women) who underwent Whipple surgery for PDAC between January 2009 and December 2014. Three radiologists independently reviewed baseline and subsequent postoperative contrast-enhanced abdominopelvic CT examinations performed within 2 years postoperatively, evaluating features in the SAR PDAC DFP consensus statement relating to surgical bed stranding, surgical bed soft tissue, vessel encasement, main pancreatic duct dilatation, and ascites. Interreader agreement was calculated. The reference standard for LR development within 2 years postoperatively incorporated all available information. Imaging features' frequencies were calculated for recurrence examinations (i.e., first surveillance examinations indicating LR). For baseline postoperative examinations, features associations' with eventual LR development were assessed by multivariable logistic regression analysis. Results: LR developed within 2 years postoperatively in 81/126 patients. For both baseline and subsequent examinations, agreement for stranding and soft tissue morphology were poor, for vessel encasement was fair, for soft tissue and ascites were moderate, and for main pancreatic duct dilatation was substantial. On recurrence examinations, across readers, new or increased stranding was present in 27-77%; new or increased soft tissue, 80-86%; soft tissue with vessel encasement and luminal narrowing, 36-59%; new or increased main pancreatic duct dilatation, 25-26%; and new or increased ascites, 20-23%. On baseline postoperative examinations, independent predictors of eventual LR were soft tissue for all three readers (OR=2.78-6.85) and stranding for reader 1 (OR=3.59); main pancreatic duct dilatation and ascites were not independent predictors of LR for any reader. Conclusion: This study highlights the role of soft tissue, particularly when associated with vessel encasement and luminal narrowing, in raising suspicion for LR after PDAC resection. Clinical Impact: This study supports the SAR PDAC DFP consensus statement, while highlighting opportunities for continued optimization.

Imaging of pancreatic ductal adenocarcinoma - An update for all stages of patient management

Background

Pancreatic ductal adenocarcinoma (PDAC) is a common and lethal cancer. From diagnosis to disease staging, response to neoadjuvant therapy assessment and patient surveillance after resection, imaging plays a central role, guiding the multidisciplinary team in decision-planning.

Review aims and findings

This review discusses the most up-to-date imaging recommendations, typical and atypical findings, and issues related to each step of patient management. Example cases for each relevant condition are presented, and a structured report for disease staging is suggested.

Conclusion

Despite current issues in PDAC imaging at different stages of patient management, the radiologist is essential in the multidisciplinary team, as the conveyor of relevant imaging findings crucial for patient care.

Current Treatment of Potentially Resectable Pancreatic Ductal Adenocarcinoma: A Medical Oncologist's Perspective

Pancreatic cancer has traditionally been associated with a dismal prognosis, even in early stages of the disease. In recent years, the introduction of newer generation chemotherapy regimens in the adjuvant setting has improved the survival of patients treated with upfront resection. However, there are multiple theoretical advantages to deliver early systemic therapy in patients with localized pancreatic cancer. So far, the evidence supports the use of neoadjuvant therapy for patients with borderline resectable pancreatic cancer. The benefit of this treatment sequence for patients with resectable disease remains elusive. In this review, we summarize the data on adjuvant therapy for pancreatic cancer and describe which evidence backs the use of neoadjuvant therapy. Additionally, we address important issues faced in clinical practice when treating patients with localized pancreatic cancer.

Postoperative surveillance of pancreatic ductal adenocarcinoma (PDAC) recurrence: practice pattern on standardized imaging and reporting from the society of abdominal radiology disease focus panel on PDAC

PURPOSE

Surgical resection is the only potential curative treatment for patients with pancreatic ductal adenocarcinoma (PDAC), but unfortunately most patients recur within 5 years of surgery. This article aims to assess the practice patterns across major academic institutions and develop consensus recommendations for postoperative imaging and interpretation in patients with PDAC.

METHODS

The consensus recommendations for postoperative imaging surveillance following PDAC resection were developed using the Delphi method. Members of the Society of Abdominal Radiology (SAR) PDAC Disease Focused Panel (DFP) underwent three rounds of surveys followed by live webinar group discussions to develop consensus recommendations.

RESULTS

Significant variations currently exist in the postoperative surveillance of PDAC, even among academic institutions. Differentiating common postoperative inflammatory and fibrotic changes from tumor recurrence remains a diagnostic challenge, and there is no reliable size threshold or growth rate of imaging findings that can provide differentiation. A new liver lesion or peritoneal nodule should be considered suspicious for tumor recurrence, and the imaging features should be interpreted in the appropriate clinical context (e.g., CA 19-9, clinical presentation, pathologic staging).

CONCLUSION

Postoperative imaging following PDAC resection is challenging to interpret due to the presence of confounding postoperative inflammatory changes. A standardized reporting template for locoregional findings and report impression may improve communication of relaying risk of recurrence with referring providers, which merits validation in future studies.

Patterns of disease relapse and posttreatment follow-up of patients with resected pancreatic adenocarcinoma: A single-center analysis

BACKGROUND AND OBJECTIVES

To describe the patterns of disease relapse and follow-up of patients with resected pancreatic adenocarcinoma. Additionally, we looked at patients' characteristics at relapse and survival.

METHODS

We included patients with potentially resectable pancreatic adenocarcinoma diagnosed from 2008 to 2018 who were submitted to resection with clear macroscopic margins and started posttreatment surveillance.

RESULTS

The study population consists of 73 patients. The median interval between imaging studies was 3.2 months during the first 2 years of follow-up and 5.1 months thereafter. Forty-eight patients (65.8%) experienced disease relapse. The most frequent single site of relapse was locoregional (N = 21; 43.8%). At relapse, 31 patients (64.6%) were symptomatic and forty-two patients (87.6%) had Eastern Cooperative Oncology Group performance status 0 or 1. Most patients were able to undergo additional anticancer therapy (N = 41; 85.4%). Patients with asymptomatic relapses experienced longer median postrelapse survival (25.4 vs. 11.3 months; p = 0.015).

CONCLUSIONS

A follow-up protocol that included imaging studies every 3 months in the first 2 years and every 6 months thereafter is able to diagnose disease relapse when patients have adequate performance status and are still able to undergo additional anticancer treatment.

Pancreatic Adenocarcinoma: Diagnostic Errors, Contributing Factors and Solutions

The purpose of this article is to review diagnostic errors in preoperative and post-operative imaging for pancreatic ductal adenocarcinoma (PDAC), discuss contributing factors, and provide solutions that minimize errors. Accurate radiological staging and restaging of PDAC dictates surgical management and errors can have significant negative effects on patient care, such as missed vessel involvement or metastatic disease that would preclude surgery. Familiarity with these errors and their contributing factors improves diagnostic accuracy and ultimately leads to improved patient outcomes.

Comparative efficacy of modified FOLFIRINOX, gemcitabine plus capecitabine and gemcitabine plus nab-paclitaxel as adjuvant treatment for resected pancreatic cancer: a Bayesian network meta-analysis

Background

There are no head-to-head comparisons evaluating the efficacy of the main polychemotherapy regimens used for patients with pancreatic cancer in the adjuvant setting. We aimed to describe the relative efficacy of modified FOLFIRINOX (mFOLFIRINOX), gemcitabine plus capecitabine (GEM-CAP) and gemcitabine plus nab-paclitaxel (GEM-NAB) in this setting using a Bayesian network approach.

Methods

We collected data from the ESPAC-4, PRODIGE 24 and APACT trials. Disease-free survival (DFS), according to the investigators, and overall survival (OS) for the three polychemotherapy regimens were compared using gemcitabine as the reference arm. We ran Markov chain Monte Carlo simulations with a fixed-effect model to generate the posterior distribution of the hazard ratios (HRs) using non-informative priors. Relative efficacy was measured by HRs, surface under cumulative ranking and rankograms.

Results

mFOLFIRINOX was the chemotherapy regimen most likely to be the most effective in the adjuvant setting (98.9% and 89.6% probability for DFS and OS, respectively). GEM-NAB marginally improved DFS (HR = 0.97, 95% credible interval (95% CrI) = 0.77–1.21) and OS (HR = 0.98, 95% CrI = 0.76–1.25) when compared to GEM-CAP. However, GEM-NAB had the highest chances of being the second most active chemotherapy regimen (61.4% and 52.5% probability for DFS and OS, respectively), whereas GEM-CAP was less likely to represent the second most active regimen (37.7% and 40.1% probability for DFS and OS, respectively).

Conclusion

For patients eligible and fit enough to undergo adjuvant treatment with mFOLFIRINOX, this constitutes the treatment of choice. For those with contraindications to mFOLFIRINOX, while both GEM-NAB and GEM-CAP can be considered appropriate alternatives, GEM-NAB is likely the most effective regimen.

Portal encasement: Significant CT findings to diagnose local recurrence after pancreaticoduodenectomy for pancreatic cancer

BACKGROUND/OBJECTIVES

To demonstrate the utility of portal encasement as a criterion for early diagnosis of local recurrence (LR) after pancreaticoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC).

METHODS

A total of 61 patients who underwent PD for PDAC were included in this retrospective study. Portal stenosis was evaluated by sequential postoperative computed tomography (CT) scans and correlated with disease recurrence. In addition to the conventional LR diagnostic criterion of a growing soft tissue mass, LR was evaluated using portal encasement as an additional diagnostic criterion. Portal encasement was defined as progressive stenosis of the portal system accompanied by a soft tissue mass, notwithstanding the enlargement of the mass.

RESULTS

Benign portal stenosis was found on the first postoperative CT imaging in 16 patients. However, stenosis resolved a median of 81 days later in all but one patient whose stenosis was due to portal reconstruction during PD. Portal encasement could be distinguished from benign portal stenosis based on the timing of emergence of the portal stenosis. Portal encasement developed in 13 of the 19 patients with LR, including 6 patients in whom the finding of portal encasement led to the diagnosis of LR a median of 147 days earlier with our diagnostic criterion compared with the conventional diagnostic criteria.

CONCLUSIONS

Portal encasement should be considered as a promising diagnostic criterion for earlier diagnosis of LR after PD for PDAC.

Elucidating early CT after pancreatico-duodenectomy: a primer for radiologists

Abstract

Pancreatico-duodenectomy (PD) represents the standard surgical treatment for resectable malignancies of the pancreatic head, distal common bile duct, periampullary region and duodenum, and is also performed to manage selected benign tumours and refractory chronic pancreatitis. Despite improved surgical techniques and acceptable mortality, PD remains a technically demanding, high-risk operation burdened with high morbidity (complication rates 40–50% of patients). Multidetector computed tomography (CT) represents the mainstay modality to rapidly investigate the postoperative abdomen, and to provide a consistent basis for an appropriate choice between conservative, interventional or surgical treatment. However, radiologists require familiarity with the surgically altered anatomy, awareness of expected imaging appearances and possible complications to correctly interpret early post-PD CT studies. This paper provides an overview of surgical indications and techniques, discusses risk factors and clinical manifestations of the usual postsurgical complications, and suggests appropriate techniques and indications for early postoperative CT imaging. Afterwards, the usual, normal early post-PD CT findings are presented, including transient fluid, pneumobilia, delayed gastric emptying, identification of pancreatic gland remnant and of surgical anastomoses. Finally, several imaging examples review the most common and some unusual complications such as pancreatic fistula, bile leaks, abscesses, intraluminal and extraluminal haemorrhage, and acute pancreatitis.

Teaching Points

• Pancreatico-duodenectomy (PD) is a technically demanding surgery burdened with high morbidity (40–50%).

• Multidetector CT is the mainstay technique to investigate suspected complications following PD.

• Interpreting post-PD CT requires knowledge of surgically altered anatomy and expected findings.

• CT showing collection at surgical site supports clinico-biological diagnosis of pancreatic fistula.

• Other complications include biliary leaks, haemorrhage, abscesses and venous thrombosis.

Imaging findings of recurrent pancreatic cancer following resection

Pancreatic cancer is a challenging malignancy to treat, largely due to aggressive regional involvement, early systemic dissemination, high recurrence rate, and subsequent low patient survival. Generally, 15-20% of newly diagnosed pancreatic cancers are candidates for possible curative resection. Eighty percent of these patients, however, will experience locoregional or distant recurrence in first 2 years. Although there is no strong evidence-based guideline for optimal surveillance after pancreatic cancer resection, careful comparison of surveillance follow-up multi-detector CT (MDCT) studies with a postoperative baseline MDCT examination aids detection of early recurrent pancreatic cancer. In this review article, we describe imaging findings suggestive of recurrent pancreatic cancer and review routine and alternative imaging options.

Span-1 and CA19-9 as Predictors of Early Recurrence and Lymph Node Metastasis for Patients with Invasive Pancreatic Cancer after Pancreatectomy

Because pancreatic cancer is a disease with a dismal prognosis due to the high rate of early recurrence even after curative surgery, selecting the most effective treatment in an individual requires pre-operative assessment of the tumor characteristics, including the potential for early recurrence. The study cohort included 84 patients undergoing surgical resection of pancreatic cancer. Univariate and multivariate analyses were conducted to identify the risk factors for early recurrence within six months after curative resection. Early recurrence was associated with a platelet-lymphocyte ratio ≥0.23 ( P = 0.04), carbohydrate antigen 19-9 (CA19-9) ≥200 ( P = 0.01), and S-pancreas-1 antigen (Span-1) ≥37 ( P = 0.0004) by univariate analysis. Multivariate analysis identified CA19-9 ≥200 and Span-1 ≥37 as independent risk factors for early recurrence. Patients with both risk factors had a significantly higher rate of lymph node metastasis than those with no or one risk factor. Span-1 ≥ 37 and CA19-9 ≥ 200 are independent risk factors for early recurrence in patients who underwent surgical resection, and the combination of Span-1 ≥37 and CA19-9 ≥200 is a useful indicator of lymph node metastasis.

Multimodality treatment of recurrent pancreatic cancer: Mith or reality?

Pancreatic adenocarcinoma is the fourth cause of cancer-related death in the United States. Surgery is the only potentially curative treatment, but most patients present at diagnosis with unresectable or metastatic disease. Moreover, even with an R0 resection, the majority of patients will die of disease recurrence. Most recurrences occur in the first 2-year after pancreatic resection, and are commonly located in the abdomen, even if distant metastases can occur. Recurrent pancreatic adenocarcinoma remains a significant therapeutic challenge, due to the limited role of surgery and radio-chemotherapy. Surgical management of recurrence is usually unreliable because tumor relapse typically presents as a technically unresectable, or as multifocal disease with an aggressive growth. Therefore, treatment of patients with recurrent pancreatic adenocarcinoma has historically been limited to palliative chemotherapy or supportive care. Only few data are available in the Literature about this issue, even if in recent years more studies have been published to determine whether treatment after recurrence have any effect on patients outcome. Recent therapeutic advances have demonstrated the potential to improve survival in selected patients who had undergone resection for pancreatic cancer. Multimodality management of recurrent pancreatic carcinoma may lead to better survival and quality of life in a small but significant percentage of patients; however, more and larger studies are needed to clarify the role of the different therapeutic options and the optimal way to combine them.

Pearls and pitfalls of imaging metastatic disease from pancreatic adenocarcinoma: a systematic review

Pancreatic adenocarcinoma is a systemic disease due to the presence of metastatic disease at the time of diagnosis and local recurrence as well as distant metastatic disease after treatment in a majority of patients. Recognition of these metastatic sites may help in accurate staging and assessment of therapeutic response. The authors discuss and illustrate imaging findings of metastatic disease from pancreatic adenocarcinoma in different organ systems with emphasis on entities that can mimic metastatic pancreatic cancer.

Use of diffusion-weighted MRI to differentiate chronic pancreatitis from pancreatic cancer

OBJECTIVE

The purpose of this study was to compare diffusion-weighted MRI (DWI) and conventional (non-DWI) MRI sequences in differentiating mass-forming chronic pancreatitis from pancreatic cancer.

MATERIALS AND METHODS

A retrospective cohort study included 36 patients who underwent pancreatic resection for pancreatic cancer (n = 13) and chronic pancreatitis (n = 23) after preoperative MRI with DWI. Two independent reviewers assessed the DW images for signal intensity and apparent diffusion coefficient (ADC) values. Four weeks later, they reviewed the other MR images for size of mass, double-duct sign, pancreatic duct cutoff, and perivascular soft-tissue cuffing. A score for conventional MRI was given with 1 meaning definitely benign and 5 meaning definitely malignant. Univariate and multivariate analyses and receiver operating characteristic (ROC) curve analysis were performed with surgical pathologic examination as the reference standard.

RESULTS

The only finding that differentiated the two groups was the presence of a well-defined mass, favoring the diagnosis of cancer (p = 0.02, p < 0.01). There was no significant difference between the two groups in signal intensity on DW images (p = 0.82, p = 0.85) or ADC (p = 0.51, p = 0.76). Double-duct sign, pancreatic duct cutoff, and perivascular soft-tissue cuffing were not useful in differentiating the two groups. The areas under the ROC curve were 0.873 and 0.878 for the conventional MRI scores, compared with 0.602 and 0.552 for ADC measurements (p = 0.02, p = 0.008).

CONCLUSION

The addition of DWI to conventional MRI does not facilitate differentiation of pancreatic cancer from chronic pancreatitis.

CT diagnosis of recurrence after pancreatic cancer: Is there a pattern?

AIM: To investigate predilection sites of recurrence of pancreatic cancer by computed tomography (CT) in follow-up after surgery.

METHODS: Seventy seven patients with recurrence after pancreatic cancer surgery were retrospectively identified. The operative technique, R-status, T-stage and development of tumor markers were evaluated. Two radiologists analyzed CT scans with consensus readings. Location of local recurrence, lymph node recurrence and organ metastases were noted. Surgery and progression of findings on follow-up CT were considered as reference standard.

RESULTS: The mean follow-up interval was 3.9 ± 1.8 mo, with a mean relapse-free interval of 12.9 ± 10.4 mo. The predominant site of recurrence was local (65%), followed by lymph node (17%), liver metastasis (11%) and peritoneal carcinosis (7%). Local recurrence emerged at the superior mesenteric artery (n = 28), the hepatic artery (n = 8), in an area defined by the surrounding vessels: celiac trunk, portal vein, inferior vena cava (n = 22), and in a space limited by the mesenteric artery, portal vein and inferior vena cava (n = 17). Lymph node recurrence occurred in the mesenteric root and left lateral to the aorta. Recurrence was confirmed by surgery (n = 22) and follow-up CT (n = 55). Tumor markers [carbohydrate antigen 19-9 (CA19-9), carcinoembryonic antigen (CEA)] increased in accordance with signs of recurrence in most cases (86% CA19-9; 79.2% CEA).

CONCLUSION: Specific changes of local and lymph node recurrence can be found in the course of the cardinal peripancreatic vessels. The superior mesenteric artery is the leading structure for recurrence.

Preoperative diagnosis of lymph node metastasis in biliary and pancreatic carcinomas: evaluation of the combination of multi-detector CT and serum CA19-9 level

BACKGROUND

It is difficult to diagnose lymph node metastasis in biliary and pancreas carcinomas before surgery.

AIM

The aim of this study was to assess the utility of the combination of multi-detector computed tomographic (MDCT) findings and serum carbohydrate antigen (CA)19-9 level in the diagnosis of lymph node metastasis in biliary and pancreas carcinomas.

METHODS

The subjects were 139 patients with biliary and pancreas carcinomas who underwent surgical resection. We calculated the positive predictive values (PPV), sensitivities, specificities, positive likelihood ratios (PLR) and accuracies of diagnosis by MDCT alone, serum CA19-9 level alone, and their combination.

RESULTS

The PPV and sensitivity were higher for node metastasis in hepatoduodenal ligament than in common hepatic artery (CHA) or para-aortic region (PAR). Specificity, accuracy and PLR were highest for CHA in biliary carcinoma. With pancreatic carcinoma, PLR was slightly higher in PAR compared to other regions. The sensitivity of CA19-9 for node metastasis was higher than that of MDCT, while the PPV, specificity, accuracy and PLR were low for both biliary and pancreas carcinoma. The combination of positive CT findings and high CA19-9 level had the highest positive rate for node metastasis for both types of carcinomas. Nodes around the supra-mesenteric vein could not be fully observed on CT.

CONCLUSION

The combination of high-resolution MDCT and CA19-9 is useful for the diagnosis of lymph node metastasis in biliary and pancreas carcinomas.

[Computerized tomography in postoperative monitoring of patients with the Whipple operation--characteristics of CT findings]

We presented the postoperative CT findings of patients after the Whipple's operation (cephalic pancreaticoduodenectomy), performed for the pancreatic head cancer, or ampullary carcinoma. Technique of the Whipple's operation is described, and normal and pathological postoperative CT findings, which are characteristic for the immediate (early) and delayed (late) follow-up period, are presented. In addition, difficulties in differentiation of afferent jejunal loop from the recurrent tumor by CT are discussed, and references from the literature about the possibilities of successful visualization of the afferent jejunal loop are cited. Possible locations and CT appearances of the tumor recurrences are presented. An overview of the literature is provided.