Preoperative locoregional re-evaluation by endoscopic ultrasound in pancreatic ductal adenocarcinoma after neoadjuvant chemoradiation

Endoscopic Ultrasound Criteria for Arterial Invasion in Pancreatic Cancer of the Body and Tail

OBJECTIVES

We aimed to determine the difference in endoscopic ultrasonography (EUS) images between portal vein (PV) and arterial invasion of pancreatic cancer and to develop criteria for arterial involvement.

METHODS

We reviewed EUS data of consecutive patients who underwent distal pancreatectomy from December 2010 to May 2017. We categorized the tumor-vessel relationship into 4 and 5 types, respectively, for the PV and arteries: (a) clear separation between tumor and vessel; (b) tumor border at vessel, echo-rich vessel wall uninterrupted; (c) echo-rich vessel wall interrupted; (d) vessel contour irregularity; and (e) arterial wall thickening or echogenic band surrounding the artery. We compared EUS outcomes with surgical and pathological results.

RESULTS

Overall, 56 patients underwent distal pancreatectomy, of whom 22 received en bloc celiac axis resection. The pathological invasion rates of PVs and arteries were 46.2% and 0% in (c), and 72.5% and 42.4% in (d) (P = 0.046, P = 0.016), respectively. The overall sensitivity and specificity were 92.1% and 83.2%, respectively, for diagnosing venous invasion and 70.0% and 84.4%, respectively, for arterial invasion.

CONCLUSIONS

Different EUS criteria may be necessary for diagnosing arterial and portal venous invasions. Criterion (d) might be appropriate for diagnosing arterial invasion.

Diagnostic accuracy of different imaging modalities following computed tomography (CT) scanning for assessing the resectability with curative intent in pancreatic and periampullary cancer

BACKGROUND

Periampullary cancer includes cancer of the head and neck of the pancreas, cancer of the distal end of the bile duct, cancer of the ampulla of Vater, and cancer of the second part of the duodenum. Surgical resection is the only established potentially curative treatment for pancreatic and periampullary cancer. A considerable proportion of patients undergo unnecessary laparotomy because of underestimation of the extent of the cancer on computed tomography (CT) scanning. Other imaging methods such as magnetic resonance imaging (MRI), positron emission tomography (PET), PET-CT, and endoscopic ultrasound (EUS) have been used to detect local invasion or distant metastases not visualised on CT scanning which could prevent unnecessary laparotomy. No systematic review or meta-analysis has examined the role of different imaging modalities in assessing the resectability with curative intent in patients with pancreatic and periampullary cancer.

OBJECTIVES

To determine the diagnostic accuracy of MRI, PET scan, and EUS performed as an add-on test or PET-CT as a replacement test to CT scanning in detecting curative resectability in pancreatic and periampullary cancer.

SEARCH METHODS

We searched MEDLINE, Embase, Science Citation Index Expanded, and Health Technology Assessment (HTA) databases up to 5 November 2015. Two review authors independently screened the references and selected the studies for inclusion. We also searched for articles related to the included studies by performing the "related search" function in MEDLINE (OvidSP) and Embase (OvidSP) and a "citing reference" search (by searching the articles that cite the included articles).

SELECTION CRITERIA

We included diagnostic accuracy studies of MRI, PET scan, PET-CT, and EUS in patients with potentially resectable pancreatic and periampullary cancer on CT scan. We accepted any criteria of resectability used in the studies. We included studies irrespective of language, publication status, or study design (prospective or retrospective). We excluded case-control studies.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed data extraction and quality assessment using the QUADAS-2 (quality assessment of diagnostic accuracy studies - 2) tool. Although we planned to use bivariate methods for analysis of sensitivities and specificities, we were able to fit only the univariate fixed-effect models for both sensitivity and specificity because of the paucity of data. We calculated the probability of unresectability in patients who had a positive index test (post-test probability of unresectability in people with a positive test result) and in those with negative index test (post-test probability of unresectability in people with a positive test result) using the mean probability of unresectability (pre-test probability) from the included studies and the positive and negative likelihood ratios derived from the model. The difference between the pre-test and post-test probabilities gave the overall added value of the index test compared to the standard practice of CT scan staging alone.

MAIN RESULTS

Only two studies (34 participants) met the inclusion criteria of this systematic review. Both studies evaluated the diagnostic test accuracy of EUS in assessing the resectability with curative intent in pancreatic cancers. There was low concerns about applicability for most domains in both studies. The overall risk of bias was low in one study and unclear or high in the second study. The mean probability of unresectable disease after CT scan across studies was 60.5% (that is 61 out of 100 patients who had resectable cancer after CT scan had unresectable disease on laparotomy). The summary estimate of sensitivity of EUS for unresectability was 0.87 (95% confidence interval (CI) 0.54 to 0.97) and the summary estimate of specificity for unresectability was 0.80 (95% CI 0.40 to 0.96). The positive likelihood ratio and negative likelihood ratio were 4.3 (95% CI 1.0 to 18.6) and 0.2 (95% CI 0.0 to 0.8) respectively. At the mean pre-test probability of 60.5%, the post-test probability of unresectable disease for people with a positive EUS (EUS indicating unresectability) was 86.9% (95% CI 60.9% to 96.6%) and the post-test probability of unresectable disease for people with a negative EUS (EUS indicating resectability) was 20.0% (5.1% to 53.7%). This means that 13% of people (95% CI 3% to 39%) with positive EUS have potentially resectable cancer and 20% (5% to 53%) of people with negative EUS have unresectable cancer.

AUTHORS' CONCLUSIONS

Based on two small studies, there is significant uncertainty in the utility of EUS in people with pancreatic cancer found to have resectable disease on CT scan. No studies have assessed the utility of EUS in people with periampullary cancer.There is no evidence to suggest that it should be performed routinely in people with pancreatic cancer or periampullary cancer found to have resectable disease on CT scan.

Endoscopic ultrasonography for tumor node staging and vascular invasion in pancreatic cancer: a meta-analysis

BACKGROUND/AIMS

The accurate staging of pancreatic cancer (PanCa) is crucial in the development of a stage-specific treatment plan for PanCa patients. We aimed to perform a meta-analysis of endoscopic ultrasonography (EUS) in the tumor node (TN) staging and evaluation of vascular invasion in PanCa.

METHODS

A meta-analysis of diagnostic accuracy parameters was performed to evaluate the EUS-based TN staging, and vascular invasion by PanCa was compared to the results of intraoperative staging or to the histopathology of resected specimens.

RESULTS

Twenty studies with 726 PanCa cases were identified from 281 articles. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were 0.72, 0.90, 6.27, 0.28, and 24.69, respectively, for T1-2 staging and 0.90, 0.72, 3.58, 0.16, and 24.69, respectively, for T3-4 staging. The overall sensitivity, specificity, PLR, NLR, and DOR were 0.62, 0.74, 2.54, 0.51, and 6.67, respectively, for N staging (positive vs. negative) and 0.87, 0.92, 7.16, 0.20, and 56.19, respectively, for vascular invasion. The area under the curve was 0.90, 0.90, 0.79, and 0.94 for T1-2 staging, T3-4 staging, N staging, and vascular invasion, respectively.

CONCLUSIONS

EUS is a reliable and accurate diagnostic tool for the TN staging and evaluation of vascular invasion in PanCa. The nodal staging accuracy using EUS is less satisfactory.

Does preoperative therapy optimize outcomes in patients with resectable pancreatic cancer?

The objective of this study was to compare survival between all patients with radiographically resectable adenocarcinoma of the proximal pancreas who underwent preoperative chemoradiation therapy (PRE-OP CRT) or surgical exploration first (SURGERY) with "intention to resect." Pancreatic cancer patients who undergo resection after PREOP CRT live longer than patients who undergo resection without PREOP CRT, a difference that may be attributable to patient selection. We retrospectively identified 236 patients with pancreatic head adenocarcinoma seen between 1999 and 2007 with sufficient data to be confirmed medically and radiographically resectable. The outcomes of 144 patients who underwent PREOP CRT were compared to those of 92 patients who proceeded straight to SURGERY. The groups were similar in age and gender. Tumors were slightly larger in the PREOP CRT group (mean 2.5 cm vs. 2.1 cm, P < 0.01), and there were trends toward more venous abutment (54% vs. 39%, P = 0.06) and a higher Charlson comorbidity index (P = 0.1). In the PREOP CRT group, 76 patients (53%) underwent resection, 28 (19%) had metastatic and 17 (12%) locally unresectable disease after PREOP CRT, and 23 (16%) were not explored due to performance status or loss to follow-up. In the SURGERY group, 68 patients (74%) underwent resection. Sixteen patients (17%) had metastatic and eight patients (9%) locally unresectable disease at exploration. In patients who underwent resection, the PREOP CRT group had smaller pathologic tumor size and lower incidence of positive lymph nodes than the SURGERY group but no difference in positive margins or need for vascular resection. Median overall survival (OS) in patients undergoing resection was 27 months in the PREOP CRT group and 17 months in the SURGERY group (P = 0.04). Median OS in all patients treated with PREOP CRT or surgically explored with intention to resect was 15 and 13 months, respectively, with superimposable survival curves. Despite a lower resection rate, the PREOP CRT group as a whole had a similar OS to the SURGERY group as a whole. For patients who underwent resection, those in the PREOP CRT had longer survival than those in the SURGERY group, suggesting that PREOP CRT allows better patient selection for resection. PREOP CRT should be considered an acceptable alternative for most patients with resectable pancreatic cancer.

Pancreatic head resectable adenocarcinoma: preoperative chemoradiation improves local control but does not affect survival

BACKGROUND

This study assesses the impact of preoperative chemoradiation on recurrence, surgical morbidity, histopathological data and survival in resectable adenocarcinoma of the pancreatic head.

METHODS

We carried out a retrospective study with an intention-to-treat analysis. From 1997 to 2006, 173 patients with resectable pancreas head carcinoma were treated in two reference centres in France using different treatment strategies.

RESULTS

Sixty-seven of 85 (79%) patients in the surgery-first (SF) group and 38 of 88 (43%) patients in the chemoradiation (CR) group underwent surgical resection (P < 0.001). Overall morbidity was 40% (15/38) in the CR group and 43% (29/67) in the SF group (P= 0.837). In the CR group, median tumour size was smaller (1.5 cm vs. 3.0 cm; P < 0.001) and fewer patients were node-positive (29% vs. 64%; P= 0.001) than in the SF group. There was less perineural (43% vs. 93%; P < 0.001), lymphatic and vascular (21% vs. 92%; P < 0.001) invasion in the CR group than in the SF group. In both groups, 89% of patients had recurrence (31/35 in the CR group and 57/64 in the SF group; P= 1.000), predominantly involving metastasis and carcinomatosis in the CR group (30/31 vs. 35/57; P < 0.001) and locoregional recurrence in the SF group (24/57 vs. 3/31; P= 0.002). Median survival for all patients and for resected patients in the CR and SF groups was, respectively, 15 months vs. 17 months, and 21 months vs. 18 months (P= non-significant).

CONCLUSIONS

Preoperative chemoradiation allows for good local control of the disease but does not increase survival, mainly for reasons of metastatic spread. Other options should be developed to improve both local and distant control of the disease.

Endoscopic ultrasound staging and novel therapeutics for pancreatic cancer

Pancreatic cancer remains a challenging disease, being the fourth leading cause of death in both men and women in the United States. Patients with pancreatic cancer present with symptoms including jaundice, pruritus, and weight loss, which often herald advanced disease with little chance for curative resection. Multiple imaging modalities are used to diagnose and stage pancreatic cancer. This article discusses the utility of endoscopic ultrasound (EUS) for diagnosis and staging, and introduces novel EUS-guided therapeutic options for the treatment of pancreatic cancers. EUS-guided fine-needle injection of chemotherapy agents is a promising development in pancreatic tumor treatment.

Role of endoscopic ultrasound in pancreatic cancer

Pancreatic cancer (PC) is the fourth most common cause of cancer deaths in Western societies. It is an aggressive tumor with an overall 5-year survival rate of less than 5%. Surgical resection offers the only possibility of cure and long-term survival for patients suffering from PC; however, unfortunately, fewer than 20% of patients suffering from PC have disease that is amendable to surgical resection. Therefore, it is important to accurately diagnose and stage these patients to enable optimal treatment of their disease. The imaging modalities involved in the diagnosis and staging of PC include multidetector CT scanning, endoscopic ultrasound (EUS), endoscopic retrograde cholangiopancreaticography and MRI. The roles and relative importance of these imaging modalities have changed over the last few decades and continue to change owing to the rapid technological advances in medical imaging, but these investigations continue to be complementary. EUS was first introduced in the mid-1980s in Japan and Germany and has quickly gained acceptance. Its widespread use in the last decade has revolutionized the management of pancreatic disease as it simultaneously provides primary diagnostic and staging information, as well as enabling tissue biopsy. This article discusses the potential benefits and drawbacks of EUS in the primary diagnosis, staging and assessment of resectability, and EUS-guided fine-needle aspiration in PC. Difficult diagnostic scenarios and pitfalls are also discussed. A suggested management algorithm for patients with suspected PC is also presented.

A prolonged follow-up provides new insights into locally advanced pancreatic cancer treatment

We report the case of a 64-year-old woman treated for a locally advanced pancreatic adenocarcinoma, which could not undergo radical resection due to encasement of the superior mesenteric artery. After chemoradiotherapy (six weeks), normalization of plasma CA19.9 levels was documented and CT showed shrinkage of the pancreatic mass but persistent encasement of the SMA. Surgical exploration followed by radical resection was performed 18 months later. Resection of the pancreatic head was then performed and the final pathological analysis showed a complete response. This case is unique in terms of the duration of follow-up between chemoradiotherapy and radical resection and raises two main concerns regarding the current standard of care of locally advanced pancreatic tumors; first, the difficulty of assessing the tumor response to chemoradiotherapy, second, the unfeasibility of establishing the timing of surgery, its indications and the survival benefits for patients with an objective response to therapy.

Adénocarcinomes pancréatiques localement évolués. Chimioradiothérapie, réévaluation et résection secondaire ?

Induction chemoradiotherapy (CRT) may downstage locally advanced pancreatic tumors but secondary resections are unfrequent. However some responders' patients may benefit of a R0 resection.

PATIENTS AND METHODS

We report 18 resections among 29 locally advanced pancreatic cancers; 15 patients were treated with neoadjuvant 5-FU-cisplatin based (13) or taxotere based (2 patients) chemoradiotherapy (45 Gy), and 3 patients without histologically proven adenocarcinoma were resected without any preoperative treatment.

RESULTS

The morbidity rate was 28% and the mortality rate was 7%; one patient died after resection (5.5%) and one died after exploration (9%). The R0 resection rate was 50%. The median survival for the resected patients was not reached and the actuarial survival at 3 years was 59%. Two specimens showed no residual tumor and the two patients were alive at 15 and 46 months without recurrence; one specimen showed less than 10% viable tumoral cells and the patient was alive at 36 months without recurrence. A mesenteric infarction was the cause of a late death at 3 years in a disease free patient (radiation induced injury of the superior mesenteric artery). The median survival of the 11 non-resected patients was 21 months and the actuarial survival at 2 years was 0%. When the number of the resected patients (18) was reported to the entire cohort of the patients with locally advanced pancreatic cancer treated during the same period in our institution, the secondary resectability rate was 9%.

CONCLUSION

Preoperative chemoradiotherapy identifies poor surgical candidates through observation and may enhance the margin status of patients undergoing secondary resection for locally advanced tumors. However it remains difficult to evaluate the results in the literature because of the variations in the definitions of resectability. The best therapeutic strategy remains to be defined, because the majority of patients ultimately succumb with distant metastatic disease.

New advances in pancreatic imaging

PURPOSE OF REVIEW

This review serves to highlight new technology and novel applications of existing techniques and their role in the management of pancreatic diseases, including acute and chronic pancreatitis, pancreatic cancer, and pancreatic cystic neoplasms.

RECENT FINDINGS

Contrast-enhanced ultrasound has shown promise in evaluating the severity of acute pancreatitis, staging pancreatic cancer, and predicting malignancy in cystic neoplasms. Optical coherence tomography within the pancreatic duct appears to be able to differentiate malignant and normal pancreatic ducts. Spectroscopy may prove useful in differentiating focal chronic pancreatitis from malignancy. Multidetector-row computed tomography may provide more accurate information regarding cancer respectability and differentiation between ductal type of intraductal papillary mucinous tumors.

SUMMARY

These new developments will help with the diagnosis and staging of pancreatic diseases.