[Adenocarcinomas of the pancreas: how best to evaluate resectability?]

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.

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

BACKGROUND

Surgical resection is the only 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. Laparoscopy can detect metastases not visualised on CT scanning, enabling better assessment of the spread of cancer (staging of cancer). This is an update to a previous Cochrane Review published in 2013 evaluating the role of diagnostic laparoscopy in assessing the resectability with curative intent in people with pancreatic and periampullary cancer.

OBJECTIVES

To determine the diagnostic accuracy of diagnostic laparoscopy performed as an add-on test to CT scanning in the assessment of curative resectability in pancreatic and periampullary cancer.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE via PubMed, EMBASE via OvidSP (from inception to 15 May 2016), and Science Citation Index Expanded (from 1980 to 15 May 2016).

SELECTION CRITERIA

We included diagnostic accuracy studies of diagnostic laparoscopy in people with potentially resectable pancreatic and periampullary cancer on CT scan, where confirmation of liver or peritoneal involvement was by histopathological examination of suspicious (liver or peritoneal) lesions obtained at diagnostic laparoscopy or laparotomy. 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 tool. The specificity of diagnostic laparoscopy in all studies was 1 because there were no false positives since laparoscopy and the reference standard are one and the same if histological examination after diagnostic laparoscopy is positive. The sensitivities were therefore meta-analysed using a univariate random-effects logistic regression model. The probability of unresectability in people who had a negative laparoscopy (post-test probability for people with a negative test result) was calculated using the median probability of unresectability (pre-test probability) from the included studies, and the negative likelihood ratio derived from the model (specificity of 1 assumed). The difference between the pre-test and post-test probabilities gave the overall added value of diagnostic laparoscopy compared to the standard practice of CT scan staging alone.

MAIN RESULTS

We included 16 studies with a total of 1146 participants in the meta-analysis. Only one study including 52 participants had a low risk of bias and low applicability concern in the patient selection domain. The median pre-test probability of unresectable disease after CT scanning across studies was 41.4% (that is 41 out of 100 participants who had resectable cancer after CT scan were found to have unresectable disease on laparotomy). The summary sensitivity of diagnostic laparoscopy was 64.4% (95% confidence interval (CI) 50.1% to 76.6%). Assuming a pre-test probability of 41.4%, the post-test probability of unresectable disease for participants with a negative test result was 0.20 (95% CI 0.15 to 0.27). This indicates that if a person is said to have resectable disease after diagnostic laparoscopy and CT scan, there is a 20% probability that their cancer will be unresectable compared to a 41% probability for those receiving CT alone.A subgroup analysis of people with pancreatic cancer gave a summary sensitivity of 67.9% (95% CI 41.1% to 86.5%). The post-test probability of unresectable disease after being considered resectable on both CT and diagnostic laparoscopy was 18% compared to 40.0% for those receiving CT alone.

AUTHORS' CONCLUSIONS

Diagnostic laparoscopy may decrease the rate of unnecessary laparotomy in people with pancreatic and periampullary cancer found to have resectable disease on CT scan. On average, using diagnostic laparoscopy with biopsy and histopathological confirmation of suspicious lesions prior to laparotomy would avoid 21 unnecessary laparotomies in 100 people in whom resection of cancer with curative intent is planned.

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

BACKGROUND

Surgical resection is the only 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. Laparoscopy can detect metastases not visualised on CT scanning, enabling better assessment of the spread of cancer (staging of cancer). There has been no systematic review or meta-analysis assessing the role of diagnostic laparoscopy in assessing the resectability with curative intent in patients with pancreatic and periampullary cancer.

OBJECTIVES

To determine the diagnostic accuracy of diagnostic laparoscopy performed as an add-on test to CT scanning in the assessment of curative resectability in pancreatic and periampullary cancer.

SEARCH METHODS

We searched the Cochrane Register of Diagnostic Test Accuracy Studies, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE via PubMed, EMBASE via OvidSP (from inception to 13 September 2012), and Science Citation Index Expanded (from 1980 to 13 September 2012).

SELECTION CRITERIA

We included diagnostic accuracy studies of diagnostic laparoscopy in patients with potentially resectable pancreatic and periampullary cancer on CT scan, where confirmation of liver or peritoneal involvement was by histopathological examination of suspicious (liver or peritoneal) lesions obtained at diagnostic laparoscopy or laparotomy. 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 authors independently performed data extraction and quality assessment using the QUADAS-2 tool. The specificity of diagnostic laparoscopy in all studies was 1 because there were no false positives since laparoscopy and the reference standard are one and the same if histological examination after diagnostic laparoscopy is positive. Therefore, the sensitivities were meta-analysed using a univariate random-effects logistic regression model. The probability of unresectability in patients who had a negative laparoscopy (post-test probability for patients with a negative test result) was calculated using the median probability of unresectability (pre-test probability) from the included studies and the negative likelihood ratio derived from the model (specificity of 1 assumed). The difference between the pre-test and post-test probabilities gave the overall added value of diagnostic laparoscopy compared to the standard practice of CT scan staging alone.

MAIN RESULTS

Fifteen studies with a total of 1015 patients were included in the meta-analysis. Only one study including 52 patients had a low risk of bias and low applicability concern in the patient selection domain. The median pre-test probability of unresectable disease after CT scanning across studies was 40.3% (that is 40 out of 100 patients who had resectable cancer after CT scan were found to have unresectable disease on laparotomy). The summary sensitivity of diagnostic laparoscopy was 68.7% (95% CI 54.3% to 80.2%). Assuming a pre-test probability of 40.3%, the post-test probability of unresectable disease for patients with a negative test result was 0.17 (95% CI 0.12 to 0.24). This indicates that if a patient is said to have resectable disease after diagnostic laparoscopy and CT scan, there is a 17% probability that their cancer will be unresectable compared to a 40% probability for those receiving CT alone.A subgroup analysis of patients with pancreatic cancer gave a summary sensitivity of 67.9% (95% CI 41.1% to 86.5%). The post-test probability of unresectable disease after being considered resectable on both CT and diagnostic laparoscopy was 18% compared to 40% for those receiving CT alone.

AUTHORS' CONCLUSIONS

Diagnostic laparoscopy may decrease the rate of unnecessary laparotomy in patients with pancreatic and periampullary cancer found to have resectable disease on CT scan. On average, using diagnostic laparoscopy with biopsy and histopathological confirmation of suspicious lesions prior to laparotomy would avoid 23 unnecessary laparotomies in 100 patients in whom resection of cancer with curative intent is planned.

[Resectability evaluation in pancreatic cancer]

Accurate staging of pancreatic cancer is essential in order to select patients, which are candidates for curative resection. Multidetector computed tomography is the best imaging for determination of pancreatic cancer loco regional and distal resectability. Endoscopic ultra sonography has complementary role in small tumours. It can guide regional lymph node puncture for accurate staging. Magnetic resonance with MR angiography can be helpful in determining vascular respectability of pancreatic cancer. The use of laparoscopy with laparoscopic ultrasound has been increased last years in order to avoid unnecessary laparotomy. Positron emission tomography may be useful tool for diagnosing occult metastatic disease. It is still in evaluation.

Pancreatic cancer: incidence, treatment and survival trends--1175 cases in Calvados (France) from 1978 to 2002

AIM

To assess the trends in incidence, therapeutic modalities and survival of pancreatic cancer between 1978 and 2002 in a well-defined population, as recorded in the Calvados digestive cancer registry database.

PATIENTS AND METHODS

All patients living in Calvados with a diagnosis of pancreatic cancer were registered. Clinical data and treatment modalities were prospectively recorded. This 25-year database was divided into five 5-year periods. Data were compared using log-rank tests and the Cox model.

RESULTS

A total of 1175 cases of pancreatic cancer (617 men, 558 women) were registered. Its incidence increased with an average annual coefficient of +2.8% in men and +5.1% in women. Therapeutic modalities changed over the five time periods: surgical resection increased from 6.8 to 13.4% (median survival 15 months) while radiation therapy and/or chemotherapy also increased from 5.5 to 13.2%. Palliative surgery decreased from 54.6 to 32.0% and favored interventional endoscopic techniques. Postoperative mortality decreased significantly. Survival increased significantly over the five time periods, although the median survival time remained stable (4 months).

CONCLUSION

From 1978 to 2002, pancreatic cancer incidence increased in Calvados (France). Therapeutic modalities changed, with endoscopic treatments preferred over palliative surgery. The improvement in survival could be explained by the decrease in postoperative mortality.